Option 2. Using claim validators
#
What are session claims?SuperTokens session has a property called accessTokenPayload
. This is a JSON
object that's stored in a user's session which can be accessed on the frontend and backend. The key-values in this JSON payload are called claims.
#
What are session claim validators?Session claim validators check if the the claims in the session meet a certain criteria before giving access to a resource.
Let's take two examples:
- 2FA session claim validator: This validator checks if the session claims indicates that the user has completed both the auth factors or not.
- Email verification claim validator: This checks if the user's session indicates if they have verified their email or not.
In either case, the claim validators base their checks on the claims (or properties) present in the session's access token payload. These claims can be added by you or by the SuperTokens SDK (ex, the user roles recipe adds the roles claims to the session).
This document will guide you through how to use prebuilt session claims and session claims validators as well as how to build your own.
#
Why do we need session claim validators?The claims in the payload represent the state of the user's access properties. Session claim validators ensure that the state is up to date when the claims are being checked.
For example, if during sign in, the user has the role of "user"
, this will be added to their session by SuperTokens. If during the course of their session, the user is upgraded to an "admin"
role, then the session claim needs to be updated to reflect this as well. To do this automatically, the claim validator for roles will auto refresh the role in the session periodically. You can even specify that you want to force refresh the state when using the validator in your APIs.
Without a special construct of session claim validators, the updating of the session claims would have to be done manually by you (the developer), so to save you the time and effort, we introduced this concept.
#
Session claim interface#
On the backendBefore we dive deep into claim validators, let's talk about session claim objects. These are objects that conform to an interface that allows SuperTokens to automatically add session claims to the access token payload. Here is the interface:
import { RecipeUserId } from "supertokens-node";
interface SessionClaim<T> {
readonly key: string;
fetchValue(userId: string, recipeUserId: RecipeUserId, tenantId: string, currentPayload: JSONObject | undefined, userContext: any): Promise<T | undefined>;
addToPayload_internal(payload: JSONObject, value: T, userContext: any): JSONObject;
removeFromPayloadByMerge_internal(payload: JSONObject, userContext: any): JSONObject;
removeFromPayload(payload: JSONObject, userContext: any): JSONObject;
getValueFromPayload(payload: JSONObject, userContext: any): T | undefined;
getLastRefetchTime(payload: JSONObject, userContext: any): number | undefined;
}
T
represents a generic type. For aboolean
claim (for example if the email is verified or not), the type ofT
is aboolean
.fetchValue
is responsible for fetching the value of the claim from its source. For example, the email verification claim uses theEmailVerification.isEmailVerified
function from the email verification recipe to return aboolean
from this function.addToPayload_internal
function is responsible for adding the claim value to the inputpayload
and returning the modified payload. The payload here represents the access token's payload. Some of the in built claims in the SDK modify the payload in the following way:{
...payload,
"<key>": {
"t": <current time in milliseconds>,
"v": <value>
}
}The
key
variable is an input to theconstructor
. For the in built email verification claim, the value ofkey
is"st-ev"
.removeFromPayloadByMerge_internal
function is responsible for modifying the inputpayload
to remove the claim in such a way that ifmergeIntoAccessTokenPayload
is called, then it would remove that claim from the payload. This usually means modifying the payload like:{
...payload,
"<key>": null
}removeFromPayload
function is similar to the previous function, except that it deletes thekey
from the inputpayload
entirely.getValueFromPayload
function is supposed to return the claim's value given the inputpayload
. For the in built claims, it's usuallypayload[<key>][v]
orundefined
of thekey
doesn't exist in thepayload
.getLastRefetchTime
function returns the last time (in milliseconds) since this claim was fetched. If the claim doesn't exist in thepayload
, this function returnsundefined
.
The SDK provides a few base claim classes which make it easy for you to implement your own claims:
PrimitiveClaim
: Can be used to add any primitive type value (boolean
,string
,number
) to the session payload.PrimitiveArrayClaim
: Can be used to add any primitive array type value (boolean[]
,string[]
,number[]
) to the session payload.BooleanClaim
: A special case of thePrimitiveClaim
, used to add aboolean
type claim.
Using these, we have built a few useful claims:
EmailVerificationClaim
: This is used to store info about if the user has verified their email.RolesClaim
: This is used to store the list of roles associated with a user.PermissionClaim
: This is used to store the list of permissions associated with the user.
You can image all sorts of claims that can be built further:
- If the user has completed 2FA or not
- If the user has filled in all the profile info post sign up or not
- The last time the user authenticated themselves (useful for if you want to ask the user for their password after a certain time period).
#
On the frontendJust like the backend, the frontend also has the concept of Session claim objects which need to conform to the following interface:
type SessionClaim<T> = {
refresh(): Promise<void>;
getValueFromPayload(payload: any): T | undefined;
getLastFetchedTime(payload: any): number | undefined;
};
The
refresh
function is responsible for refreshing the claim values in the session via an API call. The API call is expected to update the claim values if required.getValueFromPayload
helps with reading the value from the session claim.getLastFetchedTime
reads the claim to return the timestamp (in milliseconds) of the last time the claim was refreshed.
When used, these objects provide a way for the SuperTokens SDK to update the claim values as and when needed. For example, in the built-in email verification claim, the refresh
function calls the backend API to check if the email is verified. That API in turn updates the session claim to reflect the email verification status. This way, even if the email was marked as verified in offline mode, the frontend will be able to get the email verification status update automatically.
Just like the backend SDK, the frontend SDK also exposes a few base claims:
#
Claim validator interface#
On the backendOnce a claim is added to the session, we must specify the checks that need to run on them during session verification. For example, if we want an API to be guarded so that only admin
roles can access them, we need a way to tell SuperTokens to do that check. This is where claim validators come into the picture. Here is the shape for a claim validator object:
type SessionClaimValidator = {
id: string;
claim: SessionClaim<any>;
shouldRefetch: (payload: any, userContext: any) => Promise<boolean>;
validate: (payload: any, userContext: any) => Promise<ClaimValidationResult>;
};
type ClaimValidationResult = { isValid: true } | { isValid: false; reason?: any };
The
id
is used to identify the session claim validator. This is useful to know which validator failed in case several of them are being checked at the same time. The value of this is usually the same as the claim object'skey
, but it can be set to anything else.The
claim
property is a reference to the claim object that's associated with this validator. TheshouldRefetch
andvalidate
functions will useclaim.getValueFromPayload
to fetch the claim value from the inputpayload
.shouldRefetch
is a function which determines if the value of the claim should be fetched again. In the in built validators, this function usually returnstrue
if the claim does not exist in thepayload
, or if it's too old.validate
function extracts the claim value from the inputpayload
(usually usingclaim.getValueFromPayload
), and determines if the validator check has passed or not. For example, if the validator is supposed to enforce that the user's email is verified, and if the claim value isfalse
, then this function would return:{
isValid: false,
message: "wrong value",
expectedValue: true,
actualValue: false
}
Using this interface and the claims interface, SuperTokens runs the following session claim validation process during session verification:
function validateSessionClaims(accessToken, claimValidators[]) {
payload = accessToken.getPayload();
// Step 1: refetch claims if required
foreach validator in claimValidators {
if (validator.shouldRefetch(payload)) {
claimValue = validator.claim.fetchValue(accessToken.sub)
payload = validator.claim.addToPayload_internal(payload, claimValue)
}
}
failedClaims = []
// Step 2: Validate all claims
foreach validator in claimValidators {
validationResult = validator.validate(payload)
if (!validationResult.isValid) {
failedClaims.push({id: validator.id, reason: validationResult.reason})
}
}
return failedClaims
}
The built-in base claims (PrimitiveClaim
, PrimitiveArrayClaim
, BooleanClaim
) all expose a set of useful validators:
PrimitiveClaim.validators.hasValue(val, maxAgeInSeconds?)
: This function call returns a validator object that enforces that the session claim has the specifiedval
.PrimitiveArrayClaim.validators.includes(val, maxAgeInSeconds?)
: This checks if the the session claims value, which is an array, includes the inputval
.PrimitiveArrayClaim.validators.excludes(val, maxAgeInSeconds?)
: This checks if the the session claims value, which is an array, excludes the inputval
.PrimitiveArrayClaim.validators.includesAll(val[], maxAgeInSeconds?)
: This checks if the the session claims value, which is an array, includes all of the items in the inputval[]
.PrimitiveArrayClaim.validators.excludesAll(val[], maxAgeInSeconds?)
: This checks if the the session claims value, which is an array, excludes all of the items in the inputval[]
.The
BooleanClaim
is built on top of thePrimitiveClaim
class, so it has the samehasValue
function, but also has additionalisTrue(maxAgeInSeconds?)
andisFalse(maxAgeInSeconds?)
functions.
In all of the above claim validators, the maxAgeInSeconds
input (which is optional) governs how often the session claim value should be refetched
- A value of
0
will make it refetch the claim value each time a check happens. - If not passed, the claim will only be refetched if it's missing in the session. The in built claims like email verification or user roles claims have a default value of five mins, meaning that those claim values are refreshed from the database after every five mins.
#
On the frontendJust like the backend, the frontend too has session claim validators that conform to the following shape
type SessionClaimValidator = {
readonly id: string;
refresh(): Promise<void>;
shouldRefresh(accessTokenPayload: any): Promise<boolean> | boolean;
validate(
accessTokenPayload: any
): Promise<ClaimValidationResult> | ClaimValidationResult;
onFailureRedirection?: (({ userContext, reason }: { userContext: any; reason: any }) => Promise<string | undefined> | string | undefined);
showAccessDeniedOnFailure?: boolean;
}
type ClaimValidationResult = { isValid: true } | { isValid: false; reason?: any };
- The
refresh
function is the same as the one in the frontend claim interface. shouldRefresh
is function which determines if the claim should be checked against the backend before callingvalidate
. This usually returnstrue
if the claim value is too old or if it is not present in theaccessTokenPayload
. When implementing this function for aSessionClaimValidator
and usingDate.now
, it's advisable to useDateProvider.now
from our SDK. This mitigates potential clock skew issues by accounting for the time difference between the frontend and backend. UseDateProvider
as shown:
import { DateProviderReference } from "supertokens-auth-react/utils/dateProvider";
DateProviderReference.getReferenceOrThrow().dateProvider.now();
- The
validate
function checks theaccessTokenPayload
for the value of the claim and returns an appropriate response.
- Using the
onFailureRedirection
callback, you can choose to redirect the user to a specific url or path if the claim validation fails. The default value of this isundefined
, which means that there will be no redirection on failure. - By setting
showAccessDeniedOnFailure
to false, you can choose to still show the contents of SessionAuth even if the claim validation fails. The default value of this istrue
, which means that if theSessionAuth
wrapper is supplied with a an access denied screen component, it will display that.
The logic for how validators are run on the frontend is the same as on the backend:
- First we
refresh
the claim if that claim'sshouldRefresh
returnstrue
(and we do this for all the claims) - Then we call the
validate
function on the claims one by one to return a array of validation result.
In case validation fails, the SessionAuth
component will:
- Automatically redirect the user to a related screen where the user can either resolve the issue or get more information if
onFailureRedirection
has been set up. For example, the email verification validator (in required mode) will redirect to the email verification screen, where the user can verify their email address. - Show an access denied screen if a component was passed in the
accessDeniedScreen
prop and the validator doesn't haveshowAccessDeniedOnFailure
set to false. E.g.: role and permission claim validatros will show the access denied screen. - Render the children with the validation error added to the session context (in
invalidClaims
) if neither of the above was applicable. E.g.: the email verification validator inOPTIONAL
mode.
And once again, just like in the backend, the frontend too exposes several helper functions like hasValue
, includes
, excludes
, isTrue
etc. for the base claim classes.
#
How to add or modify a claim in a session?note
There are "protected" claims, reserved for standard or supertokens specific use-cases. Trying to overwrite them in createNewSession
or using mergeIntoAccessTokenPayload
will result in errors.
They are: sub
, iat
, exp
, sessionHandle
, refreshTokenHash1
, parentRefreshTokenHash1
, antiCsrfToken
Once you have made your own session claim object, you need to add it to a session. There are two ways in which you can add them:
- During session creation
- Updating the session to add a claim after session creation
#
During session creationYou need to override the createNewSession
function to modify the access token payload like shown below:
- NodeJS
- GoLang
- Python
- Other Frameworks
Important
import SuperTokens from "supertokens-node";
import Session from "supertokens-node/recipe/session";
import { UserRoleClaim } from "supertokens-node/recipe/userroles";
SuperTokens.init({
supertokens: {
connectionURI: "...",
},
appInfo: {
apiDomain: "...",
appName: "...",
websiteDomain: "..."
},
recipeList: [
// ...
Session.init({
override: {
functions: (originalImplementation) => {
return {
...originalImplementation,
createNewSession: async function (input) {
let userId = input.userId;
// This goes in the access token, and is available to read on the frontend.
input.accessTokenPayload = {
...input.accessTokenPayload,
...(await UserRoleClaim.build(input.userId, input.recipeUserId, input.tenantId, undefined, input.userContext))
};
/*
At this step, the access token paylaod looks like this:
{
...input.accessTokenPayload,
st-roles: {
v: ["admin"],
t: <current time in MS>
}
}
*/
return originalImplementation.createNewSession(input);
},
};
},
},
})
]
});
import (
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
supertokens.Init(supertokens.TypeInput{
RecipeList: []supertokens.Recipe{
session.Init(&sessmodels.TypeInput{
Override: &sessmodels.OverrideStruct{
Functions: func(originalImplementation sessmodels.RecipeInterface) sessmodels.RecipeInterface {
// First we copy the original implementation func
originalCreateNewSession := *originalImplementation.CreateNewSession
// Now we override the CreateNewSession function
(*originalImplementation.CreateNewSession) = func(userID string, accessTokenPayload, sessionDataInDatabase map[string]interface{}, disableAntiCsrf *bool, tenantId string, userContext supertokens.UserContext) (sessmodels.SessionContainer, error) {
if accessTokenPayload == nil {
accessTokenPayload = map[string]interface{}{}
}
accessTokenPayload, err := userrolesclaims.UserRoleClaim.Build(userID, tenantId, accessTokenPayload, userContext)
if err != nil {
return nil, err
}
/*
At this step, the access token paylaod looks like this:
{
st-roles: {
v: ["admin"],
t: <current time in MS>
}
}
*/
return originalCreateNewSession(userID, accessTokenPayload, sessionDataInDatabase, disableAntiCsrf, tenantId, userContext)
}
return originalImplementation
},
},
}),
},
})
}
from supertokens_python import init, InputAppInfo
from supertokens_python.recipe import session
from supertokens_python.recipe.session.interfaces import RecipeInterface
from supertokens_python.recipe.userroles import UserRoleClaim
from typing import Any, Dict, Optional
def override_functions(original_implementation: RecipeInterface):
original_implementation_create_new_session = original_implementation.create_new_session
async def create_new_session(user_id: str,
access_token_payload: Optional[Dict[str, Any]],
session_data_in_database: Optional[Dict[str, Any]],
disable_anti_csrf: Optional[bool],
tenant_id: str,
user_context: Dict[str, Any]):
if access_token_payload is None:
access_token_payload = {}
access_token_payload = {
**access_token_payload,
**(await UserRoleClaim.build(user_id, tenant_id, user_context))
}
# At this step, the access token paylaod looks like this:
# {
# st-roles: {
# v: ["admin"],
# t: < current time in MS >
# }
# }
return await original_implementation_create_new_session(user_id, access_token_payload, session_data_in_database, disable_anti_csrf, tenant_id, user_context)
original_implementation.create_new_session = create_new_session
return original_implementation
init(
app_info=InputAppInfo(
api_domain="...", app_name="...", website_domain="..."),
framework='...',
recipe_list=[
session.init(
override=session.InputOverrideConfig(
functions=override_functions
)
)
]
)
In the above code snippet, we take an example of manually adding the user roles claim to the session (note that this is done automatically for you if you initialise the user roles recipe).
The build
function is a helper function which all claims have that does the following:
class Claim {
// other functions like fetchValue, getValueFromPayload etc..
function build(userId, recipeUserId, tenantId) {
claimValue = this.fetchValue(userId, recipeUserId, tenantId);
return this.addToPayload_internal({}, claimValue)
}
}
#
Post session creationOnce you have the session container object (result of session verification), you can call the fetchAndSetClaim
function on it to set the claim value in the session
- NodeJS
- GoLang
- Python
- Other Frameworks
Important
import { SessionContainer } from "supertokens-node/recipe/session";
import { UserRoleClaim } from "supertokens-node/recipe/userroles";
async function addClaimToSession(session: SessionContainer) {
await session.fetchAndSetClaim(UserRoleClaim)
}
import (
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
)
func addClaimToSession(session sessmodels.SessionContainer) {
err := session.FetchAndSetClaim(userrolesclaims.UserRoleClaim)
if err != nil {
//...
}
}
- Asyncio
- Syncio
from supertokens_python.recipe.session.interfaces import SessionContainer
from supertokens_python.recipe.userroles import UserRoleClaim
async def add_claim_to_session(session: SessionContainer):
await session.fetch_and_set_claim(UserRoleClaim)
from supertokens_python.recipe.session.interfaces import SessionContainer
from supertokens_python.recipe.userroles import UserRoleClaim
def add_claim_to_session(session: SessionContainer):
session.sync_fetch_and_set_claim(UserRoleClaim)
fetchAndSetClaim
fetches the claim value using claim.fetchValue
and adds it to the access token in the session.
There is also an offline version of fetchAndSetClaim
exposed by the Session
recipe which takes the claim and a sessionHandle
. This will update that session's access token payload in the database, so when that session refreshes, the new access token will reflect that change.
#
Manually setting a claim's value in a sessionYou can also manually set a claim's value in the session without it using the fetchValue
function. This is useful for situations in which the fetchValue
function doesn't read from a data source (ex: a database).
An example of this is the 2FA claim. The fetchValue
function always returns false
because there is no database entry that is updated when 2FA is completed - we simply update the session payload.
- NodeJS
- GoLang
- Python
- Other Frameworks
Important
import { SessionContainer } from "supertokens-node/recipe/session";
import { BooleanClaim } from "supertokens-node/recipe/session/claims";
const SecondFactorClaim = new BooleanClaim({
fetchValue: () => false,
key: "2fa-completed",
});
async function mark2FAAsComplete(session: SessionContainer) {
await session.setClaimValue(SecondFactorClaim, true)
}
import (
"github.com/supertokens/supertokens-golang/recipe/session/claims"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/supertokens"
)
func mark2FAAsComplete(session sessmodels.SessionContainer) {
SecondFactorClaim, _ := claims.BooleanClaim("2fa-completed", func(userId string, tenantId string, userContext supertokens.UserContext) (interface{}, error) {
return false, nil
}, nil)
err := session.SetClaimValue(SecondFactorClaim, true)
if err != nil {
//...
}
}
- Asyncio
- Syncio
from supertokens_python.recipe.session.interfaces import SessionContainer
from supertokens_python.recipe.session.claims import BooleanClaim
SecondFactorClaim = BooleanClaim(
key="2fa-completed", fetch_value=lambda _, __, ___: False)
async def set_2fa_claim_as_completed(session: SessionContainer):
await session.set_claim_value(SecondFactorClaim, True)
from supertokens_python.recipe.session.interfaces import SessionContainer
from supertokens_python.recipe.session.claims import BooleanClaim
SecondFactorClaim = BooleanClaim(
key="2fa-completed", fetch_value=lambda _, __, ___: False)
def set_2fa_claim_as_completed(session: SessionContainer):
session.sync_set_claim_value(SecondFactorClaim, True)
#
How to add a claim validator?In order for SuperTokens to check the claims during session verification, you need to add the claim validators in the backend / frontend SDK. On the backend, the claim validators will be run during session verification, and on the frontend, they will run when you use the <SessionAuth>
component (for pre built UI), or when you call the Session.validateClaims
function.
#
Adding a validator check globallyThis method allows you to add a claim validator such that it applies checks globally - for all your API / frontend routes. This is useful for claim validators like 2FA, when you want all users to be able to access the app only if they have completed 2FA. It also helps prevent development mistakes wherein someone may forget to explictly add the 2FA claim check for each route.
#
On the backend- NodeJS
- GoLang
- Python
- Other Frameworks
Important
import SuperTokens from "supertokens-node";
import Session from "supertokens-node/recipe/session";
import { BooleanClaim } from "supertokens-node/recipe/session/claims";
const SecondFactorClaim = new BooleanClaim({
fetchValue: () => false,
key: "2fa-completed",
});
SuperTokens.init({
supertokens: {
connectionURI: "...",
},
appInfo: {
apiDomain: "...",
appName: "...",
websiteDomain: "..."
},
recipeList: [
// ...
Session.init({
override: {
functions: (originalImplementation) => {
return {
...originalImplementation,
getGlobalClaimValidators: async function (input) {
return [...input.claimValidatorsAddedByOtherRecipes, SecondFactorClaim.validators.isTrue()]
}
};
},
},
})
]
});
import (
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
_, SessionClaimValidator := claims.BooleanClaim("2fa-completed", func(userId string, tenantId string, userContext supertokens.UserContext) (interface{}, error) {
return false, nil
}, nil)
supertokens.Init(supertokens.TypeInput{
RecipeList: []supertokens.Recipe{
session.Init(&sessmodels.TypeInput{
Override: &sessmodels.OverrideStruct{
Functions: func(originalImplementation sessmodels.RecipeInterface) sessmodels.RecipeInterface {
(*originalImplementation.GetGlobalClaimValidators) = func(userId string, claimValidatorsAddedByOtherRecipes []claims.SessionClaimValidator, tenantId string, userContext supertokens.UserContext) ([]claims.SessionClaimValidator, error) {
claimValidatorsAddedByOtherRecipes = append(claimValidatorsAddedByOtherRecipes, SessionClaimValidator.IsTrue(nil, nil))
return claimValidatorsAddedByOtherRecipes, nil
}
return originalImplementation
},
},
}),
},
})
}
from supertokens_python import init, InputAppInfo
from supertokens_python.recipe import session
from supertokens_python.recipe.session.interfaces import RecipeInterface, SessionClaimValidator
from typing import Any, Dict, List
from supertokens_python.recipe.session.claims import BooleanClaim
SecondFactorClaim = BooleanClaim(
key="2fa-completed", fetch_value=lambda _, __, ___: False)
def override_functions(original_implementation: RecipeInterface):
def get_global_claim_validators(
tenant_id: str,
user_id: str,
claim_validators_added_by_other_recipes: List[SessionClaimValidator],
user_context: Dict[str, Any],
):
claim_validators_added_by_other_recipes.append(
SecondFactorClaim.validators.is_true(None))
return claim_validators_added_by_other_recipes
original_implementation.get_global_claim_validators = get_global_claim_validators
return original_implementation
init(
app_info=InputAppInfo(
api_domain="...", app_name="...", website_domain="..."),
framework='...',
recipe_list=[
session.init(
override=session.InputOverrideConfig(
functions=override_functions
)
)
]
)
This will run the isTrue
validator check on the SecondFactorClaim
during each session verification and will only allow access to your APIs if this validator passes (i.e., the user has finished 2FA). If this validator fails, SuperTokens will send a 403
to the frontend.
note
The claim validators added this way do not run for the APIs exposed by the SuperTokens middleware.
#
On the frontend- ReactJS
- Angular
- Vue
import SuperTokens from "supertokens-web-js";
import Session, { BooleanClaim } from 'supertokens-web-js/recipe/session';
const SecondFactorClaim = new BooleanClaim({
id: "2fa-completed",
refresh: async () => {
// we do nothing here because refreshing the 2fa claim doesn't make sense
}
});
SuperTokens.init({
appInfo: {
apiDomain: "...",
appName: "...",
},
recipeList: [
//...
Session.init({
override: {
functions: (oI) => {
return {
...oI,
getGlobalClaimValidators: function (input) {
return [...input.claimValidatorsAddedByOtherRecipes, SecondFactorClaim.validators.isTrue()]
}
}
}
}
})
]
})
Now you can protect your frontend routes by using the Session.validateClaims
function as shown below:
import Session, { BooleanClaim } from "supertokens-web-js/recipe/session";
const SecondFactorClaim = new BooleanClaim({
id: "2fa-completed",
refresh: async () => {
// we do nothing here because refreshing the 2fa claim doesn't make sense
}
});
async function shouldAllowAccessToProtectedPage() {
if (await Session.doesSessionExist()) {
// Session.validateClaims will check all global validators.
let validatorFailures = await Session.validateClaims();
if (validatorFailures.length === 0) {
// all checks passed
return true;
}
if (validatorFailures.some(i => i.id === SecondFactorClaim.id)) {
// 2fa check failed
return false;
}
// some other validator failed.
}
return false;
}
import SuperTokens from "supertokens-auth-react"
import Session, { BooleanClaim } from "supertokens-auth-react/recipe/session";
const SecondFactorClaim = new BooleanClaim({
id: "2fa-completed",
refresh: async () => {
// we do nothing here because refreshing the 2fa claim doesn't make sense
}
});
SuperTokens.init({
appInfo: {
apiDomain: "...",
appName: "...",
websiteDomain: "..."
},
recipeList: [
//...
Session.init({
override: {
functions: (oI) => {
return {
...oI,
getGlobalClaimValidators: function (input) {
return [...input.claimValidatorsAddedByOtherRecipes, SecondFactorClaim.validators.isTrue()]
}
}
}
}
})
]
});
Now whenever you wrap your component with the <SessionAuth>
wrapper, SuperTokens will run the SecondFactorClaim.validators.isTrue()
validator automatically and show an access denied screen if it fails. You can see how to change this behaviour further down, in the "Handling claim validation failures" section.
import SuperTokens from "supertokens-web-js";
import Session, { BooleanClaim } from 'supertokens-web-js/recipe/session';
const SecondFactorClaim = new BooleanClaim({
id: "2fa-completed",
refresh: async () => {
// we do nothing here because refreshing the 2fa claim doesn't make sense
}
});
SuperTokens.init({
appInfo: {
apiDomain: "...",
appName: "...",
},
recipeList: [
//...
Session.init({
override: {
functions: (oI) => {
return {
...oI,
getGlobalClaimValidators: function (input) {
return [...input.claimValidatorsAddedByOtherRecipes, SecondFactorClaim.validators.isTrue()]
}
}
}
}
})
]
})
Now you can protect your frontend routes by using the Session.validateClaims
function as shown below:
import Session, { BooleanClaim } from "supertokens-web-js/recipe/session";
const SecondFactorClaim = new BooleanClaim({
id: "2fa-completed",
refresh: async () => {
// we do nothing here because refreshing the 2fa claim doesn't make sense
}
});
async function shouldAllowAccessToProtectedPage() {
if (await Session.doesSessionExist()) {
// Session.validateClaims will check all global validators.
let validatorFailures = await Session.validateClaims();
if (validatorFailures.length === 0) {
// all checks passed
return true;
}
if (validatorFailures.some(i => i.id === SecondFactorClaim.id)) {
// 2fa check failed
return false;
}
// some other validator failed.
}
return false;
}
#
Adding a validator check to a specific routeIf you want a session claim validator to run only on certain routes, then you should use this method of adding them.
To illustrate this, we will be taking an example of user roles claim validator in which we will be giving access to a user only if they have the "admin"
role.
#
On the backend- NodeJS
- GoLang
- Python
- Other Frameworks
Important
- Express
- Hapi
- Fastify
- Koa
- Loopback
- AWS Lambda / Netlify
- Next.js (Pages Dir)
- Next.js (App Dir)
- NestJS
import { verifySession } from "supertokens-node/recipe/session/framework/express";
import express from "express";
import { SessionRequest } from "supertokens-node/framework/express";
import UserRoles from "supertokens-node/recipe/userroles";
let app = express();
app.post(
"/update-blog",
verifySession({
overrideGlobalClaimValidators: async (globalValidators) => [
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
],
}),
async (req: SessionRequest, res) => {
// All validator checks have passed and the user is an admin.
}
);
import Hapi from "@hapi/hapi";
import { verifySession } from "supertokens-node/recipe/session/framework/hapi";
import {SessionRequest} from "supertokens-node/framework/hapi";
import UserRoles from "supertokens-node/recipe/userroles";
let server = Hapi.server({ port: 8000 });
server.route({
path: "/update-blog",
method: "post",
options: {
pre: [
{
method: verifySession({
overrideGlobalClaimValidators: async (globalValidators) => [
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
],
}),
},
],
},
handler: async (req: SessionRequest, res) => {
// All validator checks have passed and the user is an admin.
}
})
import Fastify from "fastify";
import { verifySession } from "supertokens-node/recipe/session/framework/fastify";
import { SessionRequest } from "supertokens-node/framework/fastify";
import UserRoles from "supertokens-node/recipe/userroles";
let fastify = Fastify();
fastify.post("/update-blog", {
preHandler: verifySession({
overrideGlobalClaimValidators: async (globalValidators) => [
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
],
}),
}, async (req: SessionRequest, res) => {
// All validator checks have passed and the user is an admin.
});
import { verifySession } from "supertokens-node/recipe/session/framework/awsLambda";
import { SessionEvent } from "supertokens-node/framework/awsLambda";
import UserRoles from "supertokens-node/recipe/userroles";
async function updateBlog(awsEvent: SessionEvent) {
// All validator checks have passed and the user is an admin.
};
exports.handler = verifySession(updateBlog, {
overrideGlobalClaimValidators: async (globalValidators) => ([
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
])
});
import KoaRouter from "koa-router";
import { verifySession } from "supertokens-node/recipe/session/framework/koa";
import {SessionContext} from "supertokens-node/framework/koa";
import UserRoles from "supertokens-node/recipe/userroles";
let router = new KoaRouter();
router.post("/update-blog", verifySession({
overrideGlobalClaimValidators: async (globalValidators) => ([
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
])
}), async (ctx: SessionContext, next) => {
// All validator checks have passed and the user is an admin.
});
import { inject, intercept } from "@loopback/core";
import { RestBindings, MiddlewareContext, post, response } from "@loopback/rest";
import { verifySession } from "supertokens-node/recipe/session/framework/loopback";
import Session from "supertokens-node/recipe/session";
import UserRoles from "supertokens-node/recipe/userroles";
class SetRole {
constructor(@inject(RestBindings.Http.CONTEXT) private ctx: MiddlewareContext) { }
@post("/update-blog")
@intercept(verifySession({
overrideGlobalClaimValidators: async (globalValidators) => ([
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
])
}))
@response(200)
async handler() {
// All validator checks have passed and the user is an admin.
}
}
import { superTokensNextWrapper } from 'supertokens-node/nextjs'
import { verifySession } from "supertokens-node/recipe/session/framework/express";
import { SessionRequest } from "supertokens-node/framework/express";
import UserRoles from "supertokens-node/recipe/userroles";
export default async function setRole(req: SessionRequest, res: any) {
await superTokensNextWrapper(
async (next) => {
await verifySession({
overrideGlobalClaimValidators: async (globalValidators) => ([
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
])
})(req, res, next);
},
req,
res
)
// All validator checks have passed and the user is an admin.
}
import { NextResponse, NextRequest } from "next/server";
import SuperTokens from "supertokens-node";
import { withSession } from "supertokens-node/nextjs";
import UserRoles from "supertokens-node/recipe/userroles";
import { backendConfig } from "@/app/config/backend";
SuperTokens.init(backendConfig());
export function POST(request: NextRequest) {
return withSession(request, async (err, session) => {
if (err) {
return NextResponse.json(err, { status: 500 });
}
// All validator checks have passed and the user is an admin.
return NextResponse.json({})
},
{
overrideGlobalClaimValidators: async function (globalClaimValidators) {
return [...globalClaimValidators, UserRoles.UserRoleClaim.validators.includes("admin")]
}
});
}
import { Controller, Post, UseGuards, Request, Response, Session } from "@nestjs/common";
import { SessionContainer, SessionClaimValidator } from "supertokens-node/recipe/session";
import { AuthGuard } from './auth/auth.guard';
import UserRoles from "supertokens-node/recipe/userroles";
@Controller()
export class ExampleController {
@Post('example')
@UseGuards(new AuthGuard({
overrideGlobalClaimValidators: async (globalValidators: SessionClaimValidator[]) => ([
...globalValidators,
UserRoles.UserRoleClaim.validators.includes("admin"),
// UserRoles.PermissionClaim.validators.includes("edit")
])
}))
async postExample(@Session() session: SessionContainer): Promise<boolean> {
// All validator checks have passed and the user is an admin.
return true;
}
}
- Chi
- net/http
- Gin
- Mux
import (
"net/http"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
_ = http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
session.VerifySession(&sessmodels.VerifySessionOptions{
OverrideGlobalClaimValidators: func(globalClaimValidators []claims.SessionClaimValidator, sessionContainer sessmodels.SessionContainer, userContext supertokens.UserContext) ([]claims.SessionClaimValidator, error) {
globalClaimValidators = append(globalClaimValidators, userrolesclaims.UserRoleClaimValidators.Includes("admin", nil, nil))
return globalClaimValidators, nil
},
}, exampleAPI).ServeHTTP(rw, r)
})
}
func exampleAPI(w http.ResponseWriter, r *http.Request) {
// TODO: session is verified and all validators have passed..
}
import (
"net/http"
"github.com/gin-gonic/gin"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
router := gin.New()
// Wrap the API handler in session.VerifySession
router.POST("/likecomment", verifySession(&sessmodels.VerifySessionOptions{
OverrideGlobalClaimValidators: func(globalClaimValidators []claims.SessionClaimValidator, sessionContainer sessmodels.SessionContainer, userContext supertokens.UserContext) ([]claims.SessionClaimValidator, error) {
globalClaimValidators = append(globalClaimValidators, userrolesclaims.UserRoleClaimValidators.Includes("admin", nil, nil))
return globalClaimValidators, nil
},
}), exampleAPI)
}
// This is a function that wraps the supertokens verification function
// to work the gin
func verifySession(options *sessmodels.VerifySessionOptions) gin.HandlerFunc {
return func(c *gin.Context) {
session.VerifySession(options, func(rw http.ResponseWriter, r *http.Request) {
c.Request = c.Request.WithContext(r.Context())
c.Next()
})(c.Writer, c.Request)
// we call Abort so that the next handler in the chain is not called, unless we call Next explicitly
c.Abort()
}
}
func exampleAPI(c *gin.Context) {
// TODO: session is verified and all claim validators pass.
}
import (
"net/http"
"github.com/go-chi/chi"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
r := chi.NewRouter()
// Wrap the API handler in session.VerifySession
r.Post("/likecomment", session.VerifySession(&sessmodels.VerifySessionOptions{
OverrideGlobalClaimValidators: func(globalClaimValidators []claims.SessionClaimValidator, sessionContainer sessmodels.SessionContainer, userContext supertokens.UserContext) ([]claims.SessionClaimValidator, error) {
globalClaimValidators = append(globalClaimValidators, userrolesclaims.UserRoleClaimValidators.Includes("admin", nil, nil))
return globalClaimValidators, nil
},
}, exampleAPI))
}
func exampleAPI(w http.ResponseWriter, r *http.Request) {
// TODO: session is verified and all claim validators pass.
}
import (
"net/http"
"github.com/gorilla/mux"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
router := mux.NewRouter()
// Wrap the API handler in session.VerifySession
router.HandleFunc("/likecomment", session.VerifySession(&sessmodels.VerifySessionOptions{
OverrideGlobalClaimValidators: func(globalClaimValidators []claims.SessionClaimValidator, sessionContainer sessmodels.SessionContainer, userContext supertokens.UserContext) ([]claims.SessionClaimValidator, error) {
globalClaimValidators = append(globalClaimValidators, userrolesclaims.UserRoleClaimValidators.Includes("admin", nil, nil))
return globalClaimValidators, nil
},
}, exampleAPI)).Methods(http.MethodPost)
}
func exampleAPI(w http.ResponseWriter, r *http.Request) {
// TODO: session is verified and all claim validators pass.
}
- FastAPI
- Flask
- Django
from supertokens_python.recipe.session.framework.fastapi import verify_session
from supertokens_python.recipe.userroles import UserRoleClaim
from supertokens_python.recipe.session import SessionContainer
from fastapi import Depends
@app.post('/like_comment')
async def like_comment(session: SessionContainer = Depends(
verify_session(
# We add the UserRoleClaim's includes validator
override_global_claim_validators=lambda global_validators, session, user_context: global_validators + \
[UserRoleClaim.validators.includes("admin")]
)
)):
# All validator checks have passed and the user has a verified email address
pass
from supertokens_python.recipe.session.framework.flask import verify_session
from supertokens_python.recipe.userroles import UserRoleClaim
@app.route('/update-jwt', methods=['POST'])
@verify_session(
# We add the UserRoleClaim's includes validator
override_global_claim_validators=lambda global_validators, session, user_context: global_validators + \
[UserRoleClaim.validators.includes("admin")]
)
def like_comment():
# All validator checks have passed and the user has a verified email address
pass
from supertokens_python.recipe.session.framework.django.asyncio import verify_session
from django.http import HttpRequest
from supertokens_python.recipe.userroles import UserRoleClaim
@verify_session(
# We add the UserRoleClaim's includes validator
override_global_claim_validators=lambda global_validators, session, user_context: global_validators + \
[UserRoleClaim.validators.includes("admin")]
)
async def like_comment(request: HttpRequest):
# All validator checks have passed and the user has a verified email address
pass
- We add the
UserRoleClaim
validator to theverifySession
function which makes sure that the user has anadmin
role. - The
globalValidators
represents other validators that apply to all API routes by default. This may include a validator that enforces that the user's email is verified (if enabled by you). - We can also add a
PermissionClaim
validator to enforce a permission.
For more complex access control, you can even extract the claim value from the session and then check the value yourself:
- NodeJS
- GoLang
- Python
- Other Frameworks
Important
- Express
- Hapi
- Fastify
- Koa
- Loopback
- AWS Lambda / Netlify
- Next.js (Pages Dir)
- Next.js (App Dir)
- NestJS
import express from "express";
import { verifySession } from "supertokens-node/recipe/session/framework/express";
import { SessionRequest } from "supertokens-node/framework/express";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
let app = express();
app.post("/update-blog", verifySession(), async (req: SessionRequest, res) => {
const roles = await req.session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
});
import Hapi from "@hapi/hapi";
import { verifySession } from "supertokens-node/recipe/session/framework/hapi";
import {SessionRequest} from "supertokens-node/framework/hapi";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
let server = Hapi.server({ port: 8000 });
server.route({
path: "/update-blog",
method: "post",
options: {
pre: [
{
method: verifySession()
},
],
},
handler: async (req: SessionRequest, res) => {
const roles = await req.session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
}
})
import Fastify from "fastify";
import { verifySession } from "supertokens-node/recipe/session/framework/fastify";
import { SessionRequest } from "supertokens-node/framework/fastify";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
let fastify = Fastify();
fastify.post("/update-blog", {
preHandler: verifySession(),
}, async (req: SessionRequest, res) => {
const roles = await req.session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
});
import { verifySession } from "supertokens-node/recipe/session/framework/awsLambda";
import { SessionEvent } from "supertokens-node/framework/awsLambda";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
async function updateBlog(awsEvent: SessionEvent) {
const roles = await awsEvent.session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
};
exports.handler = verifySession(updateBlog);
import KoaRouter from "koa-router";
import { verifySession } from "supertokens-node/recipe/session/framework/koa";
import { SessionContext } from "supertokens-node/framework/koa";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
let router = new KoaRouter();
router.post("/update-blog", verifySession(), async (ctx: SessionContext, next) => {
const roles = await ctx.session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
});
import { inject, intercept } from "@loopback/core";
import { RestBindings, MiddlewareContext, post, response } from "@loopback/rest";
import { verifySession } from "supertokens-node/recipe/session/framework/loopback";
import Session from "supertokens-node/recipe/session";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
class UpdateBlog {
constructor(@inject(RestBindings.Http.CONTEXT) private ctx: MiddlewareContext) {}
@post("/update-blog")
@intercept(verifySession())
@response(200)
async handler() {
const roles = await ((this.ctx as any).session as Session.SessionContainer).getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
}
}
import { superTokensNextWrapper } from 'supertokens-node/nextjs'
import { verifySession } from "supertokens-node/recipe/session/framework/express";
import { SessionRequest } from "supertokens-node/framework/express";
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
export default async function updateBlog(req: SessionRequest, res: any) {
await superTokensNextWrapper(
async (next) => {
await verifySession()(req, res, next);
},
req,
res
)
const roles = await req.session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
await superTokensNextWrapper(
async (next) => {
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
},
req,
res
)
}
// user is an admin..
}
import { NextResponse, NextRequest } from "next/server";
import SuperTokens from "supertokens-node";
import { withSession } from "supertokens-node/nextjs";
import UserRoles from "supertokens-node/recipe/userroles";
import { backendConfig } from "@/app/config/backend";
import { Error as STError } from "supertokens-node/recipe/session"
SuperTokens.init(backendConfig());
export function POST(request: NextRequest) {
return withSession(request, async (err, session) => {
if (err) {
return NextResponse.json(err, { status: 500 });
}
const roles = await session!.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
const error = new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
});
return NextResponse.json(error, { status: 403 });
}
// user is an admin..
return NextResponse.json({})
});
}
import { Controller, Post, UseGuards, Session } from "@nestjs/common";
import { SessionContainer } from "supertokens-node/recipe/session";
import { AuthGuard } from './auth/auth.guard';
import UserRoles from "supertokens-node/recipe/userroles";
import { Error as STError } from "supertokens-node/recipe/session"
@Controller()
export class ExampleController {
@Post('example')
@UseGuards(new AuthGuard())
async postExample(@Session() session: SessionContainer): Promise<boolean> {
const roles = await session.getClaimValue(UserRoles.UserRoleClaim);
if (roles === undefined || !roles.includes("admin")) {
// this error tells SuperTokens to return a 403 to the frontend.
throw new STError({
type: "INVALID_CLAIMS",
message: "User is not an admin",
payload: [{
id: UserRoles.UserRoleClaim.key
}]
})
}
// user is an admin..
return true;
}
}
- Chi
- net/http
- Gin
- Mux
import (
"net/http"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
sessionerror "github.com/supertokens/supertokens-golang/recipe/session/errors"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
http.ListenAndServe("SERVER ADDRESS", corsMiddleware(
supertokens.Middleware(http.HandlerFunc(func(rw http.ResponseWriter, r *http.Request) {
// Handle your APIs..
if r.URL.Path == "/update-blog" && r.Method == "POST" {
// Calling the API with session verification
session.VerifySession(nil, postExample).ServeHTTP(rw, r)
return
}
}))))
}
func corsMiddleware(next http.Handler) http.Handler {
return http.HandlerFunc(func(response http.ResponseWriter, r *http.Request) {
//...
})
}
func postExample(w http.ResponseWriter, r *http.Request) {
sessionContainer := session.GetSessionFromRequestContext(r.Context())
roles := sessionContainer.GetClaimValue(userrolesclaims.UserRoleClaim)
if roles == nil || !contains(roles.([]interface{}), "admin") {
err := supertokens.ErrorHandler(sessionerror.InvalidClaimError{
Msg: "User is not an admin",
InvalidClaims: []claims.ClaimValidationError{
{ID: userrolesclaims.UserRoleClaim.Key},
},
}, r, w)
if err != nil {
// TODO: send 500 error to client
}
}
// User is an admin...
}
func contains(s []interface{}, e string) bool {
for _, a := range s {
if a == e {
return true
}
}
return false
}
import (
"net/http"
"github.com/gin-gonic/gin"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
sessionerror "github.com/supertokens/supertokens-golang/recipe/session/errors"
"github.com/supertokens/supertokens-golang/recipe/session/sessmodels"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
router := gin.New()
router.POST("/update-blog", verifySession(nil), postExample)
}
// Wrap session.VerifySession to work with Gin
func verifySession(options *sessmodels.VerifySessionOptions) gin.HandlerFunc {
return func(c *gin.Context) {
session.VerifySession(options, func(rw http.ResponseWriter, r *http.Request) {
c.Request = c.Request.WithContext(r.Context())
c.Next()
})(c.Writer, c.Request)
// we call Abort so that the next handler in the chain is not called, unless we call Next explicitly
c.Abort()
}
}
// This is the API handler.
func postExample(c *gin.Context) {
sessionContainer := session.GetSessionFromRequestContext(c.Request.Context())
roles := sessionContainer.GetClaimValue(userrolesclaims.UserRoleClaim)
if roles == nil || !contains(roles.([]interface{}), "admin") {
err := supertokens.ErrorHandler(sessionerror.InvalidClaimError{
Msg: "User is not an admin",
InvalidClaims: []claims.ClaimValidationError{
{ID: userrolesclaims.UserRoleClaim.Key},
},
}, c.Request, c.Writer)
if err != nil {
// TODO: send 500 error to client
}
}
// User is an admin...
}
func contains(s []interface{}, e string) bool {
for _, a := range s {
if a == e {
return true
}
}
return false
}
import (
"net/http"
"github.com/go-chi/chi"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
sessionerror "github.com/supertokens/supertokens-golang/recipe/session/errors"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
r := chi.NewRouter()
r.Post("/update-blog", session.VerifySession(nil, postExample))
}
// This is the API handler.
func postExample(w http.ResponseWriter, r *http.Request) {
sessionContainer := session.GetSessionFromRequestContext(r.Context())
roles := sessionContainer.GetClaimValue(userrolesclaims.UserRoleClaim)
if roles == nil || !contains(roles.([]interface{}), "admin") {
err := supertokens.ErrorHandler(sessionerror.InvalidClaimError{
Msg: "User is not an admin",
InvalidClaims: []claims.ClaimValidationError{
{ID: userrolesclaims.UserRoleClaim.Key},
},
}, r, w)
if err != nil {
// TODO: send 500 error to client
}
}
}
func contains(s []interface{}, e string) bool {
for _, a := range s {
if a == e {
return true
}
}
return false
}
import (
"net/http"
"github.com/gorilla/mux"
"github.com/supertokens/supertokens-golang/recipe/session"
"github.com/supertokens/supertokens-golang/recipe/session/claims"
sessionerror "github.com/supertokens/supertokens-golang/recipe/session/errors"
"github.com/supertokens/supertokens-golang/recipe/userroles/userrolesclaims"
"github.com/supertokens/supertokens-golang/supertokens"
)
func main() {
router := mux.NewRouter()
router.HandleFunc("/update-blog",
session.VerifySession(nil, postExample)).Methods(http.MethodPost)
}
// This is the API handler.
func postExample(w http.ResponseWriter, r *http.Request) {
sessionContainer := session.GetSessionFromRequestContext(r.Context())
roles := sessionContainer.GetClaimValue(userrolesclaims.UserRoleClaim)
if roles == nil || !contains(roles.([]interface{}), "admin") {
err := supertokens.ErrorHandler(sessionerror.InvalidClaimError{
Msg: "User is not an admin",
InvalidClaims: []claims.ClaimValidationError{
{ID: userrolesclaims.UserRoleClaim.Key},
},
}, r, w)
if err != nil {
// TODO: send 500 error to client
}
}
}
func contains(s []interface{}, e string) bool {
for _, a := range s {
if a == e {
return true
}
}
return false
}
- FastAPI
- Flask
- Django
from fastapi import Depends
from supertokens_python.recipe.session.framework.fastapi import verify_session
from supertokens_python.recipe.session.exceptions import raise_invalid_claims_exception, ClaimValidationError
from supertokens_python.recipe.session import SessionContainer
from supertokens_python.recipe.userroles import UserRoleClaim
@app.post('/update-blog')
async def update_blog_api(session: SessionContainer = Depends(verify_session())):
roles = await session.get_claim_value(UserRoleClaim)
if roles is None or "admin" not in roles:
raise_invalid_claims_exception("User is not an admin", [
ClaimValidationError(UserRoleClaim.key, None)])
from flask import Flask, g
from supertokens_python.recipe.session.framework.flask import verify_session
from supertokens_python.recipe.session import SessionContainer
from supertokens_python.recipe.session.exceptions import raise_invalid_claims_exception, ClaimValidationError
from supertokens_python.recipe.userroles import UserRoleClaim
app = Flask(__name__)
@app.route('/update-blog', methods=['POST'])
@verify_session()
def set_role_api():
session: SessionContainer = g.supertokens
roles = session.sync_get_claim_value(UserRoleClaim)
if roles is None or "admin" not in roles:
raise_invalid_claims_exception("User is not an admin", [
ClaimValidationError(UserRoleClaim.key, None)])
from django.http import HttpRequest
from supertokens_python.recipe.session.framework.django.asyncio import verify_session
from supertokens_python.recipe.session import SessionContainer
from supertokens_python.recipe.session.exceptions import raise_invalid_claims_exception, ClaimValidationError
from supertokens_python.recipe.userroles import UserRoleClaim
@verify_session()
async def get_user_info_api(request: HttpRequest):
session: SessionContainer = request.supertokens
roles = await session.get_claim_value(UserRoleClaim)
if roles is None or "admin" not in roles:
raise_invalid_claims_exception("User is not an admin", [
ClaimValidationError(UserRoleClaim.key, None)])
#
On the frontend- ReactJS
- Angular
- Vue
import Session from "supertokens-web-js/recipe/session";
import { UserRoleClaim, /*PermissionClaim*/ } from "supertokens-web-js/recipe/userroles";
async function shouldLoadRoute(): Promise<boolean> {
if (await Session.doesSessionExist()) {
let validationErrors = await Session.validateClaims({
overrideGlobalClaimValidators: (globalValidators) =>
[...globalValidators,
UserRoleClaim.validators.includes("admin"),
/* PermissionClaim.validators.includes("modify") */
]
});
if (validationErrors.length === 0) {
// user is an admin
return true;
}
for (const err of validationErrors) {
if (err.id === UserRoleClaim.id) {
// user roles claim check failed
} else {
// some other claim check failed (from the global validators list)
}
}
}
// either a session does not exist, or one of the validators failed.
// so we do not allow access to this page.
return false
}
- We call the
validateClaims
function with theUserRoleClaim
validator which makes sure that the user has anadmin
role. - The
globalValidators
represents other validators that apply to all calls to thevalidateClaims
function. This may include a validator that enforces that the user's email is verified (if enabled by you). - We can also add a
PermissionClaim
validator to enforce a permission.
If you want to have more complex access control, you can get the roles list from the session as follows, and check the list yourself:
import Session from "supertokens-web-js/recipe/session";
import { UserRoleClaim } from "supertokens-web-js/recipe/userroles";
async function shouldLoadRoute(): Promise<boolean> {
if (await Session.doesSessionExist()) {
let roles = await Session.getClaimValue({claim: UserRoleClaim});
if (Array.isArray(roles) && roles.includes("admin")) {
// User is an admin
return true;
}
}
// either a session does not exist, or the user is not an admin
return false
}
caution
Unlike the validateClaims
function, the getClaimValue
function will not check for globally added claims. SuperTokens adds certain claims globally (for example the email verification claim in case you have enabled that recipe) which get checked only when running the validateClaims
function. Therefore, using getClaimValue
is less favourable.
Provide the overrideGlobalClaimValidators
prop to the <SessionAuth>
component as shown below
import React from "react";
import { SessionAuth } from 'supertokens-auth-react/recipe/session';
import { AccessDeniedScreen } from 'supertokens-auth-react/recipe/session/prebuiltui';
import { UserRoleClaim, /*PermissionClaim*/ } from 'supertokens-auth-react/recipe/userroles';
const AdminRoute = (props: React.PropsWithChildren<any>) => {
return (
<SessionAuth
accessDeniedScreen={AccessDeniedScreen}
overrideGlobalClaimValidators={(globalValidators) => [
...globalValidators, UserRoleClaim.validators.includes("admin"),
]
}>
{props.children}
</SessionAuth>
);
}
Above we are creating a generic component called AdminRoute
which enforces that its child components can only be rendered if the user has the admin role.
In the AdminRoute
component, we use the SessionAuth
wrapper to ensure that the session exists. We also add the UserRoleClaim
validator to the <SessionAuth>
component which checks if the validators pass or not. If all validation passes, we render the props.children
component. If the claim validation has failed, it will display the AccessDeniedScreen
component instead of rendering the children. You can also pass your own custom component to the accessDeniedScreen
prop.
note
You can extend the AdminRoute
component to check for other types of validators as well. This component can then be reused to protect all of your app's components (In this case, you may want to rename this component to something more appropriate, like ProtectedRoute
).
If you want to have more complex access control, you can get the roles list from the session as follows, and check the list yourself:
import Session from "supertokens-auth-react/recipe/session";
import {UserRoleClaim} from "supertokens-auth-react/recipe/userroles"
function ProtectedComponent() {
let claimValue = Session.useClaimValue(UserRoleClaim)
if (claimValue.loading || !claimValue.doesSessionExist) {
return null;
}
let roles = claimValue.value;
if (Array.isArray(roles) && roles.includes("admin")) {
// User is an admin
} else {
// User doesn't have any roles, or is not an admin..
}
}
caution
Unlike using the overrideGlobalClaimValidators
prop, the useClaimValue
function will not check for globally added claims. SuperTokens adds certain claims globally (for example the email verification claim in case you have enabled that recipe) which get checked only when running the <SessionAuth>
wrapper is executed. Therefore, using useClaimValue
is less favourable.
import Session from "supertokens-web-js/recipe/session";
import { UserRoleClaim, /*PermissionClaim*/ } from "supertokens-web-js/recipe/userroles";
async function shouldLoadRoute(): Promise<boolean> {
if (await Session.doesSessionExist()) {
let validationErrors = await Session.validateClaims({
overrideGlobalClaimValidators: (globalValidators) =>
[...globalValidators,
UserRoleClaim.validators.includes("admin"),
/* PermissionClaim.validators.includes("modify") */
]
});
if (validationErrors.length === 0) {
// user is an admin
return true;
}
for (const err of validationErrors) {
if (err.id === UserRoleClaim.id) {
// user roles claim check failed
} else {
// some other claim check failed (from the global validators list)
}
}
}
// either a session does not exist, or one of the validators failed.
// so we do not allow access to this page.
return false
}
- We call the
validateClaims
function with theUserRoleClaim
validator which makes sure that the user has anadmin
role. - The
globalValidators
represents other validators that apply to all calls to thevalidateClaims
function. This may include a validator that enforces that the user's email is verified (if enabled by you). - We can also add a
PermissionClaim
validator to enforce a permission.
If you want to have more complex access control, you can get the roles list from the session as follows, and check the list yourself:
import Session from "supertokens-web-js/recipe/session";
import { UserRoleClaim } from "supertokens-web-js/recipe/userroles";
async function shouldLoadRoute(): Promise<boolean> {
if (await Session.doesSessionExist()) {
let roles = await Session.getClaimValue({claim: UserRoleClaim});
if (Array.isArray(roles) && roles.includes("admin")) {
// User is an admin
return true;
}
}
// either a session does not exist, or the user is not an admin
return false
}
caution
Unlike the validateClaims
function, the getClaimValue
function will not check for globally added claims. SuperTokens adds certain claims globally (for example the email verification claim in case you have enabled that recipe) which get checked only when running the validateClaims
function. Therefore, using getClaimValue
is less favourable.
#
Handling claim validation failures#
RedirectionYou can redirect your users to a URL or path if a claim validator fails, by adding an onFailureRedirection
callback to the validator. If this callback returns a string, the SDK will try to redirect the user to that URL.
import React from "react";
import { SessionAuth, useSessionContext } from 'supertokens-auth-react/recipe/session';
import { UserRoleClaim } from 'supertokens-auth-react/recipe/userroles';
const AdminRoute = (props: React.PropsWithChildren<any>) => {
return (
<SessionAuth
overrideGlobalClaimValidators={(globalValidators) =>
[
...globalValidators,
{
...UserRoleClaim.validators.includes("admin"),
onFailureRedirection: () => "/not-an-admin"
},
]
}
>
{props.children}
</SessionAuth>
);
}
#
Showing an access denied screenAccessDeniedScreen
#
Setting an By default, the SDK will still render the children
passed to SessionAuth
even if a claim validation has failed. However, you can add an access denied screen by passing a component as accessDeniedScreen
in the SessionAuth
props. This component will be rendered instead of children
if a session claim validator has failed (see below on how you can control this on the validator level).
import React from "react";
import { SessionAuth, useSessionContext } from 'supertokens-auth-react/recipe/session';
import { AccessDeniedScreen } from 'supertokens-auth-react/recipe/session/prebuiltui';
import { UserRoleClaim, /*PermissionClaim*/ } from 'supertokens-auth-react/recipe/userroles';
const AdminRoute = (props: React.PropsWithChildren<any>) => {
return (
<SessionAuth
overrideGlobalClaimValidators={(globalValidators) =>
[...globalValidators,
UserRoleClaim.validators.includes("admin"),
]
}
accessDeniedScreen={AccessDeniedScreen}
>
{props.children}
</SessionAuth>
);
}
In the above code, we pass the AccessDeniedScreen
from our SDK, but you can make your own component as well.
#
Disabling the access denied screen for a specific validatorYou can disable the access denied screen on a per-validator basis. If showAccessDeniedOnFailure
is set to false on the validator, SessionAuth
will render the children instead of the access denied screen even if the validator fails. In this case, you can handle the invalid claims by checking the invalidClaims
prop in the session context.
This is useful in case you have several validators that are running and you want to make an exception for one of them to not show the access denied screen, but still show it for the other failures.
note
We may still shown the access denied screen if another validator fails.
import React from "react";
import { SessionAuth } from 'supertokens-auth-react/recipe/session';
import { UserRoleClaim } from 'supertokens-auth-react/recipe/userroles';
import { AccessDeniedScreen } from 'supertokens-auth-react/recipe/session/prebuiltui';
const AdminRoute = (props: React.PropsWithChildren<any>) => {
return (
<SessionAuth
overrideGlobalClaimValidators={(globalValidators) =>
[
...globalValidators,
{
...UserRoleClaim.validators.includes("admin"),
showAccessDeniedOnFailure: false,
},
]
}
accessDeniedScreen={AccessDeniedScreen}
>
{props.children}
</SessionAuth>
);
}
#
In the session contextIf a claim validation failure required neither redirection nor showing the access denied screen, you can handle failing claim validators in the children of the SessionAuth
using the invalidClaims
prop of the session context (accessed through useSessionContext
):
import Session, { BooleanClaim } from "supertokens-auth-react/recipe/session";
const SecondFactorClaim = new BooleanClaim({
id: "2fa-completed",
refresh: async () => {
// we do nothing here because refreshing the 2fa claim doesn't make sense
},
showAccessDeniedOnFailure: false
});
const Dashboard = () => {
let sessionContext = Session.useSessionContext();
if (sessionContext.loading) {
return null;
}
if (sessionContext.invalidClaims.some(i => i.id === SecondFactorClaim.id)) {
// the 2fa check failed. We should redirect the user to the second
// factor screen.
return "You cannot access this page because you have not completed 2FA";
}
// 2FA check passed
}