Configuration OAuth Providers

Purpose

Use this skill to configure oauth identity provider <name> blocks. The Caddyfile syntax is authoritative in caddyfile_identity.go and caddyfile_identity_provider.go; the provisioning behavior is authoritative in the local go-authcrunch source, especially pkg/idp/oauth/config.go.

Do not use this skill for sso provider <name> blocks. Those configure the SSO app/SAML role-assumption feature and belong in configuration-sso-app. Also do not route saml identity provider <name> blocks here; they share the parser file but use the local go-authcrunch/pkg/idp/saml implementation.

Use assets/config/home.Caddyfile as the nearest repository example for Azure, GitHub, and LinkedIn OAuth providers.

Shape

security {
	oauth identity provider azure {
		realm azure
		driver azure
		tenant_id {env.AZURE_APP_TENANT_ID}
		client_id {env.AZURE_APP_CLIENT_ID}
		client_secret {env.AZURE_APP_CLIENT_SECRET}
		scopes openid email profile
		enable id token cookie id_token AZURE_ID_TOKEN
	}

	oauth identity provider github {
		realm github
		driver github
		client_id {env.GITHUB_APP_CLIENT_ID}
		client_secret {env.GITHUB_APP_CLIENT_SECRET}
		icon github priority 100
		disable pkce
	}

	authentication portal myportal {
		enable identity provider azure github
	}
}

The identity provider name must match the portal's enable identity provider <name> value. The realm is what user transforms usually match:

transform user {
	match realm github
	action add role authp/user
}

Supported Drivers

go-authcrunch currently supports these OAuth drivers:

azure, cognito, discord, facebook, generic, github, gitlab, google, linkedin,
nextcloud, okta

Every OAuth provider needs realm, driver, client_id, and client_secret; the Caddyfile provider name becomes authcrunch's config Name. Use Caddy placeholders or secrets for client secrets.

The shortcut form is supported only for github, google, and facebook:

oauth identity provider github {env.GITHUB_APP_CLIENT_ID} {env.GITHUB_APP_CLIENT_SECRET}

Prefer full blocks when adding icons, scopes, cookie behavior, or provider toggles.

When scopes is omitted, authcrunch defaults by driver:

• github: read:user.
• facebook: email.
• discord: identify.
• nextcloud: email.
• google, cognito, linkedin, and the fallback for azure, gitlab, okta, and generic: openid email profile.

Provider Notes

• Azure: include tenant_id when targeting a tenant. If omitted, authcrunch defaults to common and computes Azure base and metadata URLs from it.
• Google: authcrunch fills Google base and metadata URLs. If client_id has no dot, authcrunch appends .apps.googleusercontent.com.
• GitHub, Facebook, and Discord: authcrunch fills authorization and token URLs and requires only access_token in the token response.
• GitLab: authcrunch defaults domain_name to gitlab.com and computes base and metadata URLs from it.
• LinkedIn: defaults to OpenID-style scopes; assets/config/home.Caddyfile enables an id token cookie for this provider.
• Okta: requires domain_name and server_id even when overriding URLs. If base_auth_url is omitted, authcrunch computes base and metadata URLs from those fields; if base_auth_url is supplied manually, also supply metadata_url unless using the explicit static-key path below.
• Cognito: requires region and user_pool_id; authcrunch computes base and metadata URLs from them.
• Nextcloud: set base_auth_url; authcrunch derives the authorization and token URLs from it.
• Generic: always set a parseable base_auth_url. Then either set metadata_url for discovery, or set authorization_url, token_url, and jwks key <kid> <pem_path> together. The current repo fixtures pair the static-key form with disable key verification; without metadata discovery, authcrunch otherwise still attempts to fetch JWKS during provider setup.

Provider-Side Claim Notes

Some OAuth failures require changes in the upstream provider console, not the Caddyfile parser:

• Discord: the default identify scope yields the Discord user identity. Add email for email claims, guilds for guild membership, and guilds.members.read for guild role checks. When user_group_filters matches a guild, authcrunch can emit roles such as discord.com/<guild_id>/members, discord.com/<guild_id>/admins, and discord.com/<guild_id>/role/<role_id> for transform matching.
• GitHub: configure App account permissions for email addresses with read-only access when /whoami or transforms need email claims. Without this provider permission and user consent, email may be absent even when the Caddyfile is valid.
• Keycloak: create realm roles or groups that correspond to application roles, assign users to them, and add client mappers for email and groups/roles so the claims appear in tokens or userinfo. Missing mappers often look like a transform bug but are provider-side configuration.
• Cognito: configure required user-pool fields, app client callback/sign-out URLs, domain, and custom attributes before login. The legacy docs note that custom attributes such as custom:roles and custom:timezone may not appear in the issued portal token without additional provider/userinfo extraction behavior.
• Ping Identity, Auth0, OneLogin, and other hosted providers often require console-side callback URL, logout URL, scope, and claim mapping setup even when the generic Caddyfile shape is correct.

Common Options

The parser accepts single-value OAuth fields such as realm, driver, tenant_id, domain_name, client_id, client_secret, server_id, base_auth_url, metadata_url, authorization_url, token_url, logout_url, region, user_pool_id, identity_token_field_name, and user_info_roles_field_name.

It accepts numeric retry and delayed-start fields:

delay_start 10
retry_attempts 5
retry_interval 5

With delay_start but no retry settings, authcrunch defaults to two attempts and uses delay_start as the retry interval. With retry_attempts but no interval, authcrunch defaults the interval to 5 seconds.

It accepts repeatable/list fields:

scopes openid email profile
user_group_filters "^github.com/example/"
user_org_filters "^example-org$"
response_type code
required_token_fields access_token id_token
jwks key main testdata/oauth/87329db33bf_pub.pem

It accepts userinfo extraction for generic OpenID providers with a discovered userinfo_endpoint:

extract email profile roles from userinfo
extract all from userinfo
user_info_roles_field_name roles

Accepted toggles include:

disable metadata discovery
disable key verification
disable pass grant type
disable response type
disable scope
disable nonce
disable tls verification
disable email claim check
disable pkce
enable accept header
enable js callback
enable logout
enable id token cookie id_token AZURE_ID_TOKEN

disable metadata discovery is parsed into metadata_discovery_disabled, but current authcrunch OAuth provider setup does not use that flag by itself to skip discovery. To avoid metadata fetching, configure explicit URLs as required by the driver and account for JWKS behavior.

logout_url also enables external provider logout behavior even without enable logout.

External logout is separate from local portal logout. Without enable logout or a manual logout_url, the portal clears local cookies but may leave the upstream IdP session active. With enable logout, authcrunch uses provider-specific logout handling when implemented. Current docs describe redirect parameter behavior for Google (continue), Azure/GitLab/Okta (post_logout_redirect_uri), Cognito (logout_uri plus client context), GitHub (logout URL without redirect parameter), and generic providers (manual URL as-is). For Facebook, Discord, LinkedIn, and Nextcloud, verify current authcrunch source before promising provider-side session termination.

For id token cookies, use the spaced Caddyfile form:

enable id token cookie
enable id token cookie id_token
enable id token cookie id_token AZURE_ID_TOKEN

The first optional value is the token response field to copy and must be id_token or access_token; the second optional value is the cookie name. When the cookie name is omitted, authcrunch uses ID_TOKEN for the provider identity-token cookie.

Review Checklist

Check generated OAuth provider entries against these code-backed constraints:

• Use oauth identity provider <name>, not sso provider <name>.
• Include realm, driver, client_id, and client_secret.
• Choose a driver supported by go-authcrunch.
• Add provider-specific required fields for Okta, Cognito, Nextcloud, and generic providers.
• For generic providers, include base_auth_url plus either metadata_url or explicit authorization_url, token_url, and static jwks key entries.
• Use enable identity provider <name> in the authentication portal.
• Use match realm <realm> in transforms when assigning roles after OAuth login.
• Use the spaced form enable id token cookie ...; avoid inventing enable id_token cookie.
• Treat disable metadata discovery as a parsed flag, not as sufficient runtime behavior by itself.
• Keep client secrets in placeholders or secret lookups.

Fixtures

Use these examples:

• assets/config/home.Caddyfile for Azure, GitHub, and LinkedIn.
• testdata/caddyfile_adapt/testcase_authenticate_with_oauth.Caddyfile for OAuth plus portal and authorization wiring.
• caddyfile_identity_provider.go for accepted Caddyfile subdirectives.
• go-authcrunch/pkg/idp/oauth/config.go for driver defaults and validation.