identity: abstract identity providers by type (#560)

Signed-off-by: Bobby DeSimone <bobbydesimone@gmail.com>

internal/identity/oauth/options.go

@@ -0,0 +1,32 @@
+// Package oauth provides support for making OAuth2 authorized and authenticated
+// HTTP requests, as specified in RFC 6749. It can additionally grant
+// authorization with Bearer JWT.
+package oauth
+
+import "net/url"
+
+// Options contains the fields required for an OAuth 2.0 (inc. OIDC) auth flow.
+//
+// https://tools.ietf.org/html/rfc6749
+// https://openid.net/specs/openid-connect-core-1_0.html#AuthRequest
+type Options struct {
+	ProviderName string
+
+	// ProviderURL is the endpoint to look for .well-known/openid-configuration
+	// OAuth2 related endpoints and will be autoconfigured based off this URL
+	ProviderURL string
+
+	// ClientID is the application's ID.
+	ClientID string
+	// ClientSecret is the application's secret.
+	ClientSecret string
+	// RedirectURL is the URL to redirect users going through
+	// the OAuth flow, after the resource owner's URLs.
+	RedirectURL *url.URL
+	// Scope specifies optional requested permissions.
+	Scopes []string
+
+	// ServiceAccount can be set for those providers that require additional
+	// credentials or tokens to do follow up API calls (e.g. Google)
+	ServiceAccount string
+}