feat: token based authentication, authenticate route, token storage

projects/greenlight/cmd/api/context.go

@@ -0,0 +1,37 @@
+package main
+
+import (
+	"context"
+	"net/http"
+
+	"greenlight.debuggingjon.dev/internal/data"
+)
+
+// Define a custom contextKey type, with the underlying type string.
+type contextKey string
+
+// Convert the string "user" to a contextKey type and assign it to the userContextKey
+// constant. We'll use this constant as the key for getting and setting user information
+// in the request context.
+const userContextKey = contextKey("user")
+
+// The contextSetUser() method returns a new copy of the request with the provided
+// User struct added to the context. Note that we use our userContextKey constant as the
+// key.
+func (app *application) contextSetUser(r *http.Request, user *data.User) *http.Request {
+	ctx := context.WithValue(r.Context(), userContextKey, user)
+	return r.WithContext(ctx)
+}
+
+// The contextSetUser() retrieves the User struct from the request context. The only
+// time that we'll use this helper is when we logically expect there to be User struct
+// value in the context, and if it doesn't exist it will firmly be an 'unexpected' error.
+// As we discussed earlier in the book, it's OK to panic in those circumstances.
+func (app *application) contextGetUser(r *http.Request) *data.User {
+	user, ok := r.Context().Value(userContextKey).(*data.User)
+	if !ok {
+		panic("missing user value in request context")
+	}
+
+	return user
+}