Implement a function to determine the ID of the Azure Pipelines runs

We want to download Git for Windows' SDK artifacts from the respective
Azure Pipelines. To that end, it is sure handy if we can identify the
latest successful run of them.

Signed-off-by: Johannes Schindelin <[email protected]>

Author: dscho

.vscode/settings.json

@@ -1,6 +1,8 @@
 {
     "cSpell.ignoreRegExpList": [
-        "mingw-w64-git"
+        "makepkg-git",
+        "mingw-w64-git",
+        "vstfs://.*"
     ],
     "cSpell.words": [
         "Pacman",

__tests__/downloader.test.ts

@@ -0,0 +1,80 @@
+import {ClientRequest, IncomingMessage} from 'http'
+import https from 'https'
+import {mocked} from 'ts-jest/utils'
+import {get} from '../src/downloader'
+
+const buildIdResponse = {
+  count: 1,
+  value: [
+    {
+      _links: [Object],
+      properties: {},
+      tags: [],
+      validationResults: [],
+      plans: [Array],
+      triggerInfo: [Object],
+      id: 71000,
+      buildNumber: '71000',
+      status: 'completed',
+      result: 'succeeded',
+      queueTime: '2021-02-16T03:11:20.8026424Z',
+      startTime: '2021-02-16T03:11:35.5385517Z',
+      finishTime: '2021-02-16T03:42:07.4413436Z',
+      url:
+        'https://dev.azure.com/Git-for-Windows/f3317b6a-fa67-40d4-9a33-b652e06943df/_apis/build/Builds/71000',
+      definition: [Object],
+      project: [Object],
+      uri: 'vstfs:///Build/Build/71000',
+      sourceBranch: 'refs/heads/main',
+      sourceVersion: 'c1d940ae0b2de75e18f642e76750f19b0f92dbc6',
+      priority: 'normal',
+      reason: 'individualCI',
+      requestedFor: [Object],
+      requestedBy: [Object],
+      lastChangedDate: '2021-02-16T03:42:07.653Z',
+      lastChangedBy: [Object],
+      orchestrationPlan: [Object],
+      logs: [Object],
+      repository: [Object],
+      keepForever: true,
+      retainedByRelease: false,
+      triggeredByBuild: null
+    }
+  ]
+}
+
+jest.mock('https')
+
+declare type Callback = (data?: object) => void
+
+test('can obtain build ID', async () => {
+  mocked(https.request).mockImplementation(
+    (
+      _url,
+      _options,
+      callback: ((res: IncomingMessage) => void) | undefined
+    ): ClientRequest => {
+      const res = {
+        statusCode: 200,
+        on: (eventType: string, eventCallback: Callback): object => {
+          switch (eventType) {
+            case 'data':
+              eventCallback(Buffer.from(JSON.stringify(buildIdResponse)))
+              break
+            case 'end':
+              eventCallback()
+              break
+          }
+          return res
+        }
+      } as IncomingMessage
+      expect(callback).not.toBeUndefined()
+      callback && callback(res)
+      const req = {} as ClientRequest
+      Object.assign(req, {on: () => {}})
+      return req
+    }
+  )
+  const {id} = await get('minimal', 'x86_64')
+  expect(id).toEqual(71000)
+})

src/downloader.ts

@@ -0,0 +1,74 @@
+import https from 'https'
+
+async function fetchJSONFromURL<T>(url: string): Promise<T> {
+  return new Promise<T>((resolve, reject) => {
+    https
+      .request(url, {}, res => {
+        if (res.statusCode !== 200) {
+          reject(
+            new Error(
+              `Got code ${res.statusCode}, URL: ${url}, message: ${res.statusMessage}`
+            )
+          )
+          return
+        }
+        const data: Uint8Array[] = []
+        res
+          .on('data', (chunk: Uint8Array) => data.push(chunk))
+          .on('end', () => {
+            try {
+              resolve(JSON.parse(Buffer.concat(data).toString('utf-8')))
+            } catch (e) {
+              reject(e)
+            }
+          })
+          .on('error', e => reject(e))
+      })
+      .on('error', e => reject(e))
+      .end()
+  })
+}
+
+export async function get(
+  flavor: string,
+  architecture: string
+): Promise<{
+  id: string
+}> {
+  if (!['x86_64', 'i686'].includes(architecture)) {
+    throw new Error(`Unsupported architecture: ${architecture}`)
+  }
+
+  let definitionId: number
+  switch (flavor) {
+    case 'minimal':
+      if (architecture === 'i686') {
+        throw new Error(`Flavor "minimal" is only available for x86_64`)
+      }
+      definitionId = 22
+      break
+    case 'makepkg-git':
+      if (architecture === 'i686') {
+        throw new Error(`Flavor "makepkg-git" is only available for x86_64`)
+      }
+      definitionId = 29
+      break
+    case 'build-installers':
+      definitionId = architecture === 'i686' ? 30 : 29
+      break
+    default:
+      throw new Error(`Unknown flavor: '${flavor}`)
+  }
+
+  const baseURL = 'https://dev.azure.com/git-for-windows/git/_apis/build/builds'
+  const data = await fetchJSONFromURL<{
+    count: number
+    value: [{id: string}]
+  }>(
+    `${baseURL}?definitions=${definitionId}&statusFilter=completed&resultFilter=succeeded&$top=1`
+  )
+  if (data.count !== 1) {
+    throw new Error(`Unexpected number of builds: ${data.count}`)
+  }
+  return {id: data.value[0].id}
+}