Inject GitHub host to be able to clone from another GitHub instance (#922)

* Adding the ability to specify the GitHub Server URL and allowing for it to differ from the Actions workflow host

* Adding tests for injecting the GitHub URL

* Addressing code review comments for PR #922

1 files changed, 25 insertions, 9 deletions

diff --git a/src/url-helper.ts b/src/url-helper.ts
index 05f1cbd..6807b7f 100644
--- a/src/url-helper.ts
+++ b/src/url-helper.ts
@@ -1,6 +1,6 @@
 import * as assert from 'assert'
-import {IGitSourceSettings} from './git-source-settings'
 import {URL} from 'url'
+import {IGitSourceSettings} from './git-source-settings'
 
 export function getFetchUrl(settings: IGitSourceSettings): string {
   assert.ok(
@@ -8,7 +8,7 @@ export function getFetchUrl(settings: IGitSourceSettings): string {
     'settings.repositoryOwner must be defined'
   )
   assert.ok(settings.repositoryName, 'settings.repositoryName must be defined')
-  const serviceUrl = getServerUrl()
+  const serviceUrl = getServerUrl(settings.githubServerUrl)
   const encodedOwner = encodeURIComponent(settings.repositoryOwner)
   const encodedName = encodeURIComponent(settings.repositoryName)
   if (settings.sshKey) {
@@ -19,11 +19,27 @@ export function getFetchUrl(settings: IGitSourceSettings): string {
   return `${serviceUrl.origin}/${encodedOwner}/${encodedName}`
 }
 
-export function getServerUrl(): URL {
-  // todo: remove GITHUB_URL after support for GHES Alpha is no longer needed
-  return new URL(
-    process.env['GITHUB_SERVER_URL'] ||
-      process.env['GITHUB_URL'] ||
-      'https://github.com'
-  )
+export function getServerUrl(url?: string): URL {
+  let urlValue =
+    url && url.trim().length > 0
+      ? url
+      : process.env['GITHUB_SERVER_URL'] || 'https://github.com'
+  return new URL(urlValue)
+}
+
+export function getServerApiUrl(url?: string): string {
+  let apiUrl = 'https://api.github.com'
+
+  if (isGhes(url)) {
+    const serverUrl = getServerUrl(url)
+    apiUrl = new URL(`${serverUrl.origin}/api/v3`).toString()
+  }
+
+  return apiUrl
+}
+
+export function isGhes(url?: string): boolean {
+  const ghUrl = getServerUrl(url)
+
+  return ghUrl.hostname.toUpperCase() !== 'GITHUB.COM'
 }