Added information about it under recipes/authentication doc

docs/content/recipes/authentication.md

@@ -113,3 +113,28 @@ func (r *queryResolver) Hero(ctx context.Context, episode Episode) (Character, e
 	return r.droid["2001"], nil
 }
 ```
+
+Things are different with websockets, and if you do things in the vein of the above example, you have to compute this at every call to `auth.ForContext`. It's a bit inefficient if you have multiple calls to this function. What you might do to mitigate that is to have a session manager on the context and have that check the vailidity in the first `auth.ForContext` call.
+
+```golang
+// ForContext finds the user from the context. REQUIRES Middleware to have run.
+func ForContext(ctx context.Context) *User {
+  raw, ok := ctx.Value(userCtxKey).(*User)
+
+  if !ok {
+    payload := graphql.GetInitPayload(ctx)
+    if payload == nil {
+      return nil
+    }
+
+    userId, err := validateAndGetUserID(payload["token"])
+    if err != nil {
+      return nil
+    }
+
+    return getUserByID(db, userId)
+  }
+
+	return raw
+}
+```