feature/codespaces proxy url (#4683)

* detect github codespaces proxy url

* only print full proxy url if we are running in the vscode terminal (as opposed to in the extension)

Author: jjallaire

src/command/preview/preview.ts

@@ -74,6 +74,8 @@ import { projectOutputDir } from "../../project/project-shared.ts";
 import { projectContext } from "../../project/project-context.ts";
 import { normalizePath, pathWithForwardSlashes } from "../../core/path.ts";
 import {
+  gitHubCodeSpacesProxyUri,
+  isGitHubCodespaces,
   isJupyterHubServer,
   isRStudioServer,
   isRStudioWorkbench,
@@ -750,6 +752,9 @@ function pdfFileRequestHandler(
           : isVSCodeServer()
           ? vsCodeServerProxyUri()!.replace("{{port}}", `${port}`) +
             kPdfJsInitialPath
+          : isGitHubCodespaces()
+          ? gitHubCodeSpacesProxyUri()!.replace("{{port}}", `${port}`) +
+            kPdfJsInitialPath
           : "/" + kPdfJsInitialPath;
         return Promise.resolve(serveRedirect(url));
       } else {

src/command/render/render-shared.ts

@@ -21,6 +21,8 @@ import { resourceFilesFromRenderedFile } from "./resources.ts";
 import { RenderFlags, RenderOptions, RenderResult } from "./types.ts";
 import { fileExecutionEngine } from "../../execute/engine.ts";
 import {
+  gitHubCodeSpacesProxyUri,
+  isGitHubCodespaces,
   isJupyterHubServer,
   isJupyterServer,
   isRStudioServer,
@@ -188,6 +190,10 @@ export async function printBrowsePreviewMessage(
     const browseUrl = proxyUrl.replace("{{port}}", `${port}`) +
       path;
     info(`\nBrowse at ${browseUrl}`, { format: colors.green });
+  } else if (isVSCodeTerminal() && isGitHubCodespaces()) {
+    const browseUrl =
+      gitHubCodeSpacesProxyUri()!.replace("{{port}}", `${port}`) + path;
+    info(`\nBrowse at ${browseUrl}`, { format: colors.green });
   } else if (isJupyterHubServer()) {
     const httpReferrer = `${
       jupyterHubHttpReferrer() || "<jupyterhub-server-url>/"

src/core/platform.ts

@@ -33,6 +33,29 @@ export function isVSCodeTerminal() {
   return Deno.env.get("TERM_PROGRAM") === "vscode";
 }
 
+export function gitHubCodespaceName() {
+  return Deno.env.get("CODESPACE_NAME");
+}
+
+export function gitHubCodespacePortForwardingDomain() {
+  return Deno.env.get("GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN");
+}
+
+export function isGitHubCodespaces() {
+  return !!gitHubCodespacePortForwardingDomain() || !!gitHubCodespaceName();
+}
+
+export function gitHubCodeSpacesProxyUri() {
+  const CODESPACE_NAME = gitHubCodespaceName();
+  const GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN =
+    gitHubCodespacePortForwardingDomain();
+  if (CODESPACE_NAME && GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN) {
+    return `https://${CODESPACE_NAME}-{{port}}.${GITHUB_CODESPACES_PORT_FORWARDING_DOMAIN}`;
+  } else {
+    return undefined;
+  }
+}
+
 export function isVSCodeServer() {
   return !!vsCodeServerProxyUri();
 }