feat: add support for app url variables (#915)

* feat: add support for app url variables

* fix: test not working

* fix: format issue

packages/common/src/app-url/base.ts

@@ -0,0 +1,23 @@
+import * as tldts from "tldts";
+
+const safeParseTldts = (url: string) => {
+  try {
+    return tldts.parse(url);
+  } catch {
+    return null;
+  }
+};
+
+export const parseAppHrefWithVariables = <TInput extends string | null>(url: TInput, currentHref: string): TInput => {
+  if (!url || url.length === 0) return url;
+
+  const tldtsResult = safeParseTldts(currentHref);
+
+  const urlObject = new URL(currentHref);
+
+  return url
+    .replaceAll("[homarr_base]", `${urlObject.protocol}//${urlObject.hostname}`)
+    .replaceAll("[homarr_hostname]", tldtsResult?.hostname ?? "")
+    .replaceAll("[homarr_domain]", tldtsResult?.domain ?? "")
+    .replaceAll("[homarr_protocol]", urlObject.protocol.replace(":", "")) as TInput;
+};

packages/common/src/app-url/client.ts

@@ -0,0 +1,5 @@
+import { parseAppHrefWithVariables } from "./base";
+
+export const parseAppHrefWithVariablesClient = <TInput extends string | null>(url: TInput): TInput => {
+  return parseAppHrefWithVariables(url, window.location.href);
+};

packages/common/src/app-url/server.ts

@@ -0,0 +1,8 @@
+import { headers } from "next/headers";
+
+import { extractBaseUrlFromHeaders } from "../url";
+import { parseAppHrefWithVariables } from "./base";
+
+export const parseAppHrefWithVariablesServer = <TInput extends string | null>(url: TInput): TInput => {
+  return parseAppHrefWithVariables(url, extractBaseUrlFromHeaders(headers()));
+};

packages/common/src/client.ts

@@ -0,0 +1 @@
+export * from "./app-url/client";

packages/common/src/server.ts

@@ -1 +1,2 @@
+export * from "./app-url/server";
 export * from "./security";

packages/common/src/url.ts

@@ -1,3 +1,5 @@
+import type { ReadonlyHeaders } from "next/dist/server/web/spec-extension/adapters/headers";
+
 export const appendPath = (url: URL | string, path: string) => {
   const newUrl = new URL(url);
   newUrl.pathname = removeTrailingSlash(newUrl.pathname) + path;
@@ -7,3 +9,16 @@ export const appendPath = (url: URL | string, path: string) => {
 const removeTrailingSlash = (path: string) => {
   return path.at(-1) === "/" ? path.substring(0, path.length - 1) : path;
 };
+
+export const extractBaseUrlFromHeaders = (headers: ReadonlyHeaders): `${string}://${string}` => {
+  let protocol = headers.get("x-forwarded-proto") ?? "http";
+
+  // @see https://support.glitch.com/t/x-forwarded-proto-contains-multiple-protocols/17219
+  if (protocol.includes(",")) {
+    protocol = protocol.includes("https") ? "https" : "http";
+  }
+
+  const host = headers.get("x-forwarded-host") ?? headers.get("host");
+
+  return `${protocol}://${host}`;
+};