Fix up leftovers from kradalby PR

README.md

@@ -30,7 +30,7 @@ Headscale implements this coordination server.
 - [x] Support for alternative IP ranges in the tailnets (default Tailscale's 100.64.0.0/10)
 - [x] DNS (passing DNS servers to nodes)
 - [x] Share nodes between ~~users~~ namespaces
-- [x] SSO (via OIDC)
+- [x] Single-Sign-On (via Open ID Connect)
 - [x] MagicDNS (see `docs/`)
 
 ## Client OS support
@@ -109,13 +109,14 @@ Suggestions/PRs welcomed!
 
    ```json
    {
-   "oidc_issuer": "https://your-oidc.issuer.com/path",
-   "oidc_client_id": "your-oidc-client-id",
-   "oidc_client_secret": "your-oidc-client-secret"
+   "oidc": {
+       "issuer": "https://your-oidc.issuer.com/path",
+       "client_id": "your-oidc-client-id",
+       "client_secret": "your-oidc-client-secret",
+       "domain_map": {
+         ".*": "default-namespace"
+       }
    }
-   ```
-   
-   If `oidc_issuer` is set, headscale will attempt to send your users to the OIDC server for authentication, otherwise it will give instructions on how to authorise clients via the CLI.
 
 6. Run the server
 
@@ -237,9 +238,12 @@ The fields starting with `db_` are used for the PostgreSQL connection informatio
 
 OpenID Connect settings:
 ```
-   "oidc_issuer": "https://your-oidc.issuer.com/path",
-   "oidc_client_id": "your-oidc-client-id",
-   "oidc_client_secret": "your-oidc-client-secret"
+   oidc:
+     issuer: "https://your-oidc.issuer.com/path"
+     client_id: "your-oidc-client-id"
+     client_secret: "your-oidc-client-secret"
+     domain_map:
+       ".*": default-namespace
 ```
 
 

oidc.go

@@ -212,6 +212,10 @@ func (h *Headscale) OIDCCallback(c *gin.Context) {
 	c.String(http.StatusBadRequest, "email from claim could not be mapped to a namespace")
 }
 
+// getNamespaceFromEmail passes the users email through a list of "matchers"
+// and iterates through them until it matches and returns a namespace.
+// If no match is found, an empty string will be returned.
+// TODO(kradalby): golang Maps key order is not stable, so this list is _not_ deterministic. Find a way to make the list of keys stable, preferably in the order presented in a users configuration.
 func (h *Headscale) getNamespaceFromEmail(email string) (string, bool) {
 	for match, namespace := range h.cfg.OIDC.MatchMap {
 		regex := regexp.MustCompile(match)