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+# How to test OpenID Connect
+
+Any OpenID Connect Provider (OP) should work with Synapse, as long as it supports the authorization code flow.
+There are a few options for that:
+
+ - start a local OP. Synapse has been tested with [Hydra][hydra] and [Dex][dex-idp].
+ Note that for an OP to work, it should be served under a secure (HTTPS) origin.
+ A certificate signed with a self-signed, locally trusted CA should work. In that case, start Synapse with a `SSL_CERT_FILE` environment variable set to the path of the CA.
+ - use a publicly available OP. Synapse has been tested with [Google][google-idp].
+ - setup a SaaS OP, like [Auth0][auth0] and [Okta][okta]. Auth0 has a free tier which has been tested with Synapse.
+
+[google-idp]: https://developers.google.com/identity/protocols/OpenIDConnect#authenticatingtheuser
+[auth0]: https://auth0.com/
+[okta]: https://www.okta.com/
+[dex-idp]: https://github.com/dexidp/dex
+[hydra]: https://www.ory.sh/docs/hydra/
+
+
+## Sample configs
+
+Here are a few configs for providers that should work with Synapse.
+
+### [Dex][dex-idp]
+
+[Dex][dex-idp] is a simple, open-source, certified OpenID Connect Provider.
+Although it is designed to help building a full-blown provider, with some external database, it can be configured with static passwords in a config file.
+
+Follow the [Getting Started guide](https://github.com/dexidp/dex/blob/master/Documentation/getting-started.md) to install Dex.
+
+Edit `examples/config-dev.yaml` config file from the Dex repo to add a client:
+
+```yaml
+staticClients:
+- id: synapse
+ secret: secret
+ redirectURIs:
+ - '[synapse base url]/_synapse/oidc/callback'
+ name: 'Synapse'
+```
+
+Run with `dex serve examples/config-dex.yaml`
+
+Synapse config:
+
+```yaml
+oidc_config:
+ enabled: true
+ skip_verification: true # This is needed as Dex is served on an insecure endpoint
+ issuer: "http://127.0.0.1:5556/dex"
+ discover: true
+ client_id: "synapse"
+ client_secret: "secret"
+ scopes:
+ - openid
+ - profile
+ user_mapping_provider:
+ config:
+ localpart_template: '{{ user.name }}'
+ display_name_template: '{{ user.name|capitalize }}'
+```
+
+### [Auth0][auth0]
+
+1. Create a regular web application for Synapse
+2. Set the Allowed Callback URLs to `[synapse base url]/_synapse/oidc/callback`
+3. Add a rule to add the `preferred_username` claim.
+ <details>
+ <summary>Code sample</summary>
+
+ ```js
+ function addPersistenceAttribute(user, context, callback) {
+ user.user_metadata = user.user_metadata || {};
+ user.user_metadata.preferred_username = user.user_metadata.preferred_username || user.user_id;
+ context.idToken.preferred_username = user.user_metadata.preferred_username;
+
+ auth0.users.updateUserMetadata(user.user_id, user.user_metadata)
+ .then(function(){
+ callback(null, user, context);
+ })
+ .catch(function(err){
+ callback(err);
+ });
+ }
+ ```
+
+ </details>
+
+
+```yaml
+oidc_config:
+ enabled: true
+ issuer: "https://your-tier.eu.auth0.com/" # TO BE FILLED
+ discover: true
+ client_id: "your-client-id" # TO BE FILLED
+ client_secret: "your-client-secret" # TO BE FILLED
+ scopes:
+ - openid
+ - profile
+ user_mapping_provider:
+ config:
+ localpart_template: '{{ user.preferred_username }}'
+ display_name_template: '{{ user.name }}'
+```
+
+### GitHub
+
+GitHub is a bit special as it is not an OpenID Connect compliant provider, but just a regular OAuth2 provider.
+The `/user` API endpoint can be used to retrieve informations from the user.
+As the OIDC login mechanism needs an attribute to uniquely identify users and that endpoint does not return a `sub` property, an alternative `subject_claim` has to be set.
+
+1. Create a new OAuth application: https://github.com/settings/applications/new
+2. Set the callback URL to `[synapse base url]/_synapse/oidc/callback`
+
+```yaml
+oidc_config:
+ enabled: true
+ issuer: "https://github.com/"
+ discover: false
+ client_id: "your-client-id" # TO BE FILLED
+ client_secret: "your-client-secret" # TO BE FILLED
+ authorization_endpoint: "https://github.com/login/oauth/authorize"
+ token_endpoint: "https://github.com/login/oauth/access_token"
+ userinfo_endpoint: "https://api.github.com/user"
+ scopes:
+ - read:user
+ user_mapping_provider:
+ config:
+ subject_claim: 'id'
+ localpart_template: '{{ user.login }}'
+ display_name_template: '{{ user.name }}'
+```
+
+### Google
+
+1. Setup a project in the Google API Console
+2. Obtain the OAuth 2.0 credentials (see <https://developers.google.com/identity/protocols/oauth2/openid-connect>)
+3. Add this Authorized redirect URI: `[synapse base url]/_synapse/oidc/callback`
+
+```yaml
+oidc_config:
+ enabled: true
+ issuer: "https://accounts.google.com/"
+ discover: true
+ client_id: "your-client-id" # TO BE FILLED
+ client_secret: "your-client-secret" # TO BE FILLED
+ scopes:
+ - openid
+ - profile
+ user_mapping_provider:
+ config:
+ localpart_template: '{{ user.given_name|lower }}'
+ display_name_template: '{{ user.name }}'
+```
+
+### Twitch
+
+1. Setup a developer account on [Twitch](https://dev.twitch.tv/)
+2. Obtain the OAuth 2.0 credentials by [creating an app](https://dev.twitch.tv/console/apps/)
+3. Add this OAuth Redirect URL: `[synapse base url]/_synapse/oidc/callback`
+
+```yaml
+oidc_config:
+ enabled: true
+ issuer: "https://id.twitch.tv/oauth2/"
+ discover: true
+ client_id: "your-client-id" # TO BE FILLED
+ client_secret: "your-client-secret" # TO BE FILLED
+ client_auth_method: "client_secret_post"
+ scopes:
+ - openid
+ user_mapping_provider:
+ config:
+ localpart_template: '{{ user.preferred_username }}'
+ display_name_template: '{{ user.name }}'
+```
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