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The Auth “Resource”

This resource has many faces, and is more of a accumulation of multiple auth-related resources.

Entry Point

When accessing the Entry Point, the following resource is returned containing links to available sub resources.


Relation Description  Methods Templated
self The Entry Point itself. GET No.
curies CURIE links. GET Yes.
ec:accounts Collection of accounts. Only included for privileged users. GET No.
ec:account The single account of the logged in user. GET No.
ec:auth/register  Used to register a new account using credentials. POST Yes. Requires clientID and invite (if activated).
ec:invites List of available invites GET, POST No.
ec:auth/login Used to login using credentials POST Yes. Requires clientID.
ec:auth/logout Used to logout a logged in user GET, POST Yes. Optionally, the token can be sent as Query String.
ec:auth/password-reset Used to send an email in case a user forgot her credentials GET Yes. Requires eMail and clientID
ec:auth/email-available Used to determine if an email address is still available for registration. GET Yes. Requires the eMail address to check.
ec:auth/facebook Used to login and/or register using Facebook POST Yes. Requires clientID and invite (if activated and not registered yet).
ec:auth/google Used to login and/or register using Google POST Yes. Requires clientID and invite (if activated and not registered yet).
ec:auth/public-key Returns the Server public key as pem file for checking signed tokens. GET No.


The authentication relations (ec:auth/register, ec:auth/login, ec:auth/facebook and ec:auth/google) work different than the rest of the API. Because of OAuth authentication flow, they don't act RESTfully in the sense that they return a JSON document: instead they redirect the user agent back to the client after successful (or failing) authentication. For that matter, a valid clientID has to be sent with each request. Only valid (registered) clients can send these requests, because the callback URL the user agent gets redirected back to has to be known on the server. An access token is appended to the callback URL on redirection, or optionally sent as cookie. These requests are not designed to be used via AJAX, but plain browser HTTP (links/forms). If errors occur, a readable error code gets appended to the callback URL.



To complete the registration process, the following has to be sent in a POST Request using application/x-www-form-urlencoded (default HTML form):

Input field Description
email eMail address this account should be linked to. SHOULD be proven for availability before (using ec:auth/email-available)
password desired password for this account. Has to be at least 4 characters long.
invite (optional) invite token. Registrations may be declined without an invite token.



To log in a user using user credentials, the following has to be sent in a POST Request using application/x-www-form-urlencoded (default HTML form):

Input field Description
email eMail address of the desired account
password password for this account

For debugging (e.g. in Postman), this relation can also be sent in a JSON body. The result token is then also sent back directly, without redirects.

Google/Facebook Login


To login and optionally register using a Google or Facebook account, follow this relation (simple GET). Note that the clientID query string parameter is still needed, as well as an invite (here also sent as query string parameter) if configured. The user will redirected to the auth provider for credentials.

API Token (anonymous user)

An API Token (=Anonymous user) can only login once, on registration, and gets a JWT that is valid almost indefinitely long (about 100 Years). To obtain it, simple send an empty POST to the ec:account/create-anonymous resource. The response is the default authentication response, similar to after a regular signup.


Log out a user. The used access token's validUntil timestamp will be altered to now, which makes it unusable for further actions. This only affects this one access token – if the account is still logged in at another device, this is unaffected by the logout operation.

Variant A: GET

A plain GET request, usable for Hyperlinking, with the access token to invalidate attached as query string value for token.

Variant B: POST

POST request with Bearer authentication. The used token will be invalidated.

Both requests also require a valid clientID. The user agent will get redirected back to the registered callback URL.

Password Reset

Send the user an email with links to reset the password. GET the ec:auth/password-reset with email and clientID template parameters to trigger the password reset. The user agent will get an HTML rendered message for confirmation. The account owner will get an email with two links: for aborting and for setting the new password. Both render an HTML site. After successful resetting the password, the user will be taken back to the origin client with an login response (just as if he successfully authenticated in the first place).

Change eMail address

An eMail address change is only possible through validation (i.e. opening a link sent to the address).


The following has to be sent in a POST Request:

Input field Description
email new eMail address of the account
  • 200 ok

The response is a HTML page telling the user that an email to the new address has been sent. The change will only be permanent after the link has been opened. There will also be a link sent to the old email address. By clicking that link, the link for the new address becomes invalid. If the change has already been approved, it will be changed back to the old address.

Authentication Response

  • 302 Found

The user agent is always redirected back to the client, using the registered callbackURL. If the user has registered successfully, she is automatically logged in. However, the account state is inactive until the eMail address is validated (only register).

The access Token (as signed JSON Web Token) is appended to the callbackURL's query string as token value.

Clients may decode them using a JWT library to get the containing information: email, jti (Token ID), iat (Timestamp issued), exp (Timestamp of expiration), iss (entrecode), and sub (Account ID). To get further account information, clients can authenticate with this token at the entry point resource and follow the then contained ec:account relation to their account information.

If an Error occured, an error code is appended to the callbackURL's query string as error value. These errors are no full JSON errors as the rest of the API use, but plain strings:

Auth Errors

Error code Description
account_blocked The account is blocked, the user cannot login
account_not_found No account found for this email address
auth_error Generic auth error (probably server-side)
clientID_not_found clientID not found in client registry
db_error Generic db error (server-side)
email_unavailable An account with this email address already exists
invalid_email No valid email address
invalid_invite No valid invite code (UUIDv4)
missing_clientID clientID is missing
missing_credentials email and/or password fields are missing
password_too_short The password is too short, must be at least 4 characters long
session_not_found Internal error (session could not be re-established after external OAuth process)
token_not_found The access token could not be found
too_many_login_attempts Too many login attempts, please wait.
wrong_password Wrong password entered on login. Additionally, a lockUntil parameter is appended to the callback URL, containing a timestamp until the login is blocked.

missing_clientID and clientID_not_found are not appended to a registered callback URL but instead the user is redirected back to the HTTP Referer with those codes appended. If no Referer field is set, it triggers HTTP 400 (when missing_clientID) or HTTP 404 (when clientID_not_found).

Connecting accounts / login methods

To connect an Facebook or Google account to an existing account (no matter how it got created), or to set a password to an existing account, the above relations for registration, google and facebook can be used. If a valid access token is sent (either via HTTP Authorization header as Bearer token, or as query parameter token) with those requests, the server will try to connect the new login method with the existing account.

Public Key

The ec:public-key relation returns the Public RSA Key of the Server in PEM format for validation of the token signature.



This Resource allows verification if an eMail address is still available for registration. The following has to be sent in a GET (!) Request:

Input field Description
email eMail address of the account
  • 200 ok
Field Description
email eMail address that was checked
available true or false