feat: allow prefixes at the beginning of subdomain app hostnames (#10150)

coderd/httpapi/url_test.go

@@ -42,6 +42,17 @@ func TestApplicationURLString(t *testing.T) {
 			},
 			Expected: "8080--agent--workspace--user",
 		},
+		{
+			Name: "Prefix",
+			URL: httpapi.ApplicationURL{
+				Prefix:        "yolo---",
+				AppSlugOrPort: "app",
+				AgentName:     "agent",
+				WorkspaceName: "workspace",
+				Username:      "user",
+			},
+			Expected: "yolo---app--agent--workspace--user",
+		},
 	}
 
 	for _, c := range testCases {
@@ -123,6 +134,17 @@ func TestParseSubdomainAppURL(t *testing.T) {
 				Username:      "user-name",
 			},
 		},
+		{
+			Name:      "Prefix",
+			Subdomain: "dean---was---here---app--agent--workspace--user",
+			Expected: httpapi.ApplicationURL{
+				Prefix:        "dean---was---here---",
+				AppSlugOrPort: "app",
+				AgentName:     "agent",
+				WorkspaceName: "workspace",
+				Username:      "user",
+			},
+		},
 	}
 
 	for _, c := range testCases {