fix: retry github graphql responses whose root fields are all null

services/libs/connectors/src/connectors/github/gql.test.ts

@@ -0,0 +1,86 @@
+import { afterEach, beforeEach, describe, expect, it, vi } from 'vitest'
+
+import type { Logger } from '@crowd/logging'
+
+import type { ConnectorHttp } from '../../http/client'
+import { ProviderContractError } from '../../http/errors'
+import { githubGraphql } from './gql'
+
+const log = {
+  warn: vi.fn(),
+  error: vi.fn(),
+  info: vi.fn(),
+  debug: vi.fn(),
+} as unknown as Logger
+
+function httpReturning(responses: unknown[]): ConnectorHttp {
+  let call = 0
+  return {
+    request: vi.fn(async () => responses[Math.min(call++, responses.length - 1)]),
+    requestCount: () => call,
+  } as unknown as ConnectorHttp
+}
+
+const notFound = {
+  data: { repository: null },
+  errors: [
+    { type: 'NOT_FOUND', message: "Could not resolve to a Repository with the name 'o/r'." },
+  ],
+}
+const resolved = { data: { repository: { issue: { comments: { nodes: [] } } } } }
+
+describe('githubGraphql', () => {
+  beforeEach(() => {
+    vi.useFakeTimers()
+  })
+
+  afterEach(() => {
+    vi.useRealTimers()
+    vi.clearAllMocks()
+  })
+
+  it('retries when every root field is null alongside an error and returns the next good response', async () => {
+    const http = httpReturning([notFound, resolved])
+
+    const pending = githubGraphql(http, 'query', {}, log)
+    await vi.runAllTimersAsync()
+
+    await expect(pending).resolves.toEqual(resolved.data)
+    expect(http.request).toHaveBeenCalledTimes(2)
+  })
+
+  it('throws a provider contract error once the null-root retries are exhausted', async () => {
+    const http = httpReturning([notFound])
+
+    const pending = githubGraphql(http, 'query', {}, log)
+    const outcome = pending.catch((err) => err)
+    await vi.runAllTimersAsync()
+
+    await expect(outcome).resolves.toBeInstanceOf(ProviderContractError)
+    expect(http.request).toHaveBeenCalledTimes(5)
+  })
+
+  it('returns partial data when at least one root field resolved', async () => {
+    const partial = {
+      data: { nodes: [null, { id: 'x' }] },
+      errors: [{ type: 'NOT_FOUND', message: 'Could not resolve to a node' }],
+    }
+    const http = httpReturning([partial])
+
+    await expect(githubGraphql(http, 'query', {}, log)).resolves.toEqual(partial.data)
+    expect(http.request).toHaveBeenCalledTimes(1)
+  })
+
+  it('fails fast on a forbidden error without retrying', async () => {
+    const forbidden = {
+      data: { repository: null },
+      errors: [{ type: 'FORBIDDEN', message: 'Resource not accessible by integration' }],
+    }
+    const http = httpReturning([forbidden])
+
+    await expect(githubGraphql(http, 'query', {}, log)).rejects.toBeInstanceOf(
+      ProviderContractError,
+    )
+    expect(http.request).toHaveBeenCalledTimes(1)
+  })
+})

services/libs/connectors/src/connectors/github/gql.ts

@@ -13,6 +13,14 @@ interface GraphqlEnvelope<T> {
 const NO_DATA_MAX_ATTEMPTS = 5
 const NO_DATA_BACKOFF_MS = 2000
 
+function hasResolvedRootField(data: unknown): boolean {
+  return (
+    typeof data === 'object' &&
+    data !== null &&
+    Object.values(data).some((value) => value !== null && value !== undefined)
+  )
+}
+
 export async function githubGraphql<T>(
   http: ConnectorHttp,
   query: string,
@@ -39,7 +47,7 @@ export async function githubGraphql<T>(
         log.error({ errors: body.errors }, `github graphql errors: ${details}`)
       }
     }
-    if (body.data) {
+    if (body.data && (!body.errors?.length || hasResolvedRootField(body.data))) {
       return body.data
     }
     if (isForbidden || attempt >= NO_DATA_MAX_ATTEMPTS) {