feat: adds support for Data API in Github#getFileContents

It brings a unified function for getting file contents with or without Data API.
fixed #546

src/github.ts

@@ -675,7 +675,6 @@ export class GitHub {
     updates: Update[],
     defaultBranch: string
   ): Promise<Changes> {
-    const refName = `refs/heads/${defaultBranch}`;
     const changes = new Map();
     for (const update of updates) {
       let content;
@@ -685,17 +684,11 @@ export class GitHub {
           // hit GitHub again.
           content = {data: update.contents};
         } else {
-          content = await this.request(
-            `GET /repos/:owner/:repo/contents/:path${
-              this.proxyKey ? `?key=${this.proxyKey}` : ''
-            }`,
-            {
-              owner: this.owner,
-              repo: this.repo,
-              path: update.path,
-              ref: refName,
-            }
+          const fileContent = await this.getFileContents(
+            update.path,
+            defaultBranch
           );
+          content = {data: fileContent};
         }
       } catch (err) {
         if (err.status !== 404) throw err;
@@ -752,24 +745,82 @@ export class GitHub {
     );
   }
 
-  async getFileContents(path: string): Promise<GitHubFileContents> {
+  async getFileContentsWithSimpleAPI(
+    path: string,
+    defaultBranch: string | undefined
+  ): Promise<GitHubFileContents> {
+    const options: any = {
+      owner: this.owner,
+      repo: this.repo,
+      path,
+    };
+    if (defaultBranch) {
+      options.ref = `refs/heads/${defaultBranch}`;
+    }
     const resp = await this.request(
       `GET /repos/:owner/:repo/contents/:path${
         this.proxyKey ? `?key=${this.proxyKey}` : ''
       }`,
+      options
+    );
+    return {
+      parsedContent: Buffer.from(resp.data.content, 'base64').toString('utf8'),
+      content: resp.data.content,
+      sha: resp.data.sha,
+    };
+  }
+
+  async getFileContentsWithDataAPI(
+    path: string,
+    defaultBranch: string | undefined
+  ): Promise<GitHubFileContents> {
+    const repoTree = await this.request(
+      `GET /repos/:owner/:repo/git/trees/:branch${
+        this.proxyKey ? `?key=${this.proxyKey}` : ''
+      }`,
       {
         owner: this.owner,
         repo: this.repo,
-        path,
+        branch: defaultBranch,
+      }
+    );
+
+    const blobDescriptor = repoTree.data.tree.find(
+      (tree: any) => tree.path === path
+    );
+
+    const resp = await this.request(
+      `GET /repos/:owner/:repo/git/blobs/:sha${
+        this.proxyKey ? `?key=${this.proxyKey}` : ''
+      }`,
+      {
+        owner: this.owner,
+        repo: this.repo,
+        sha: blobDescriptor.sha,
       }
     );
+
     return {
       parsedContent: Buffer.from(resp.data.content, 'base64').toString('utf8'),
       content: resp.data.content,
       sha: resp.data.sha,
     };
   }
 
+  async getFileContents(
+    path: string,
+    defaultBranch: string | undefined = undefined
+  ): Promise<GitHubFileContents> {
+    try {
+      return await this.getFileContentsWithSimpleAPI(path, defaultBranch);
+    } catch (err) {
+      if (err.status === 403) {
+        return await this.getFileContentsWithDataAPI(path, defaultBranch);
+      }
+      throw err;
+    }
+  }
+
   async createRelease(
     packageName: string,
     version: string,

test/fixtures/github-data-api/403-too-large-file-response.json

@@ -0,0 +1,11 @@
+{
+  "message": "This API returns blobs up to 1 MB in size. The requested blob is too large to fetch via the API, but you can use the Git Data API to request blobs up to 100 MB in size.",
+  "errors": [
+    {
+      "resource": "Blob",
+      "field": "data",
+      "code": "too_large"
+    }
+  ],
+  "documentation_url": "https://docs.github.com/rest/reference/repos#get-repository-content"
+}

test/fixtures/github-data-api/data-api-trees-successful-response.json

@@ -0,0 +1,38 @@
+{
+  "sha": "1630d12c8e72e7f1441ae8afe2240d823c2d4804",
+  "url": "https://api.github.com/repos/lancedikson/release-please-403-example/git/trees/1630d12c8e72e7f1441ae8afe2240d823c2d4804",
+  "tree": [
+    {
+      "path": ".github",
+      "mode": "040000",
+      "type": "tree",
+      "sha": "cc64165cf5da91810ab7edc1143a47be42513c0a",
+      "url": "https://api.github.com/repos/lancedikson/release-please-403-example/git/trees/cc64165cf5da91810ab7edc1143a47be42513c0a"
+    },
+    {
+      "path": ".gitignore",
+      "mode": "100644",
+      "type": "blob",
+      "sha": "3c3629e647f5ddf82548912e337bea9826b434af",
+      "size": 13,
+      "url": "https://api.github.com/repos/lancedikson/release-please-403-example/git/blobs/3c3629e647f5ddf82548912e337bea9826b434af"
+    },
+    {
+      "path": "package-lock.json",
+      "mode": "100644",
+      "type": "blob",
+      "sha": "2f3d2c47bf49f81aca0df9ffc49524a213a2dc33",
+      "size": 1352120,
+      "url": "https://api.github.com/repos/lancedikson/release-please-403-example/git/blobs/2f3d2c47bf49f81aca0df9ffc49524a213a2dc33"
+    },
+    {
+      "path": "package.json",
+      "mode": "100644",
+      "type": "blob",
+      "sha": "33f90c139fca3d99a08a934fb87d30c13c68b885",
+      "size": 3995,
+      "url": "https://api.github.com/repos/lancedikson/release-please-403-example/git/blobs/33f90c139fca3d99a08a934fb87d30c13c68b885"
+    }
+  ],
+  "truncated": false
+}

test/github.ts

@@ -156,4 +156,66 @@ describe('GitHub', () => {
       req.done();
     });
   });
+
+  describe('getFileContents', () => {
+    it('should support Github Data API in case of a big file', async () => {
+      const simpleAPIResponse = JSON.parse(
+        readFileSync(
+          resolve(
+            fixturesPath,
+            'github-data-api',
+            '403-too-large-file-response.json'
+          ),
+          'utf8'
+        )
+      );
+      const dataAPITreesResponse = JSON.parse(
+        readFileSync(
+          resolve(
+            fixturesPath,
+            'github-data-api',
+            'data-api-trees-successful-response.json'
+          ),
+          'utf8'
+        )
+      );
+      const dataAPIBlobResponse = JSON.parse(
+        readFileSync(
+          resolve(
+            fixturesPath,
+            'github-data-api',
+            'data-api-blobs-successful-response.json'
+          ),
+          'utf8'
+        )
+      );
+      const req1 = nock('https://api.github.com')
+        .get(
+          '/repos/fake/fake/contents/package-lock.json?ref=refs%2Fheads%2Fmaster'
+        )
+        .reply(403, simpleAPIResponse);
+      const req2 = nock('https://api.github.com')
+        .get('/repos/fake/fake/git/trees/master')
+        .reply(200, dataAPITreesResponse);
+      const req3 = nock('https://api.github.com')
+        .get(
+          '/repos/fake/fake/git/blobs/2f3d2c47bf49f81aca0df9ffc49524a213a2dc33'
+        )
+        .reply(200, dataAPIBlobResponse);
+
+      const fileContents = await github.getFileContents(
+        'package-lock.json',
+        'master'
+      );
+      expect(fileContents).to.have.property('content');
+      expect(fileContents).to.have.property('parsedContent');
+      expect(fileContents)
+        .to.have.property('sha')
+        .equal('2f3d2c47bf49f81aca0df9ffc49524a213a2dc33');
+      snapshot(fileContents);
+      req1.done();
+      req2.done();
+      req3.done();
+    });
+  });
 });