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本文最后更新于 2648 天前,文中所述的信息可能已发生改变或更新。

0. 总览

本文为大家提供一种使用 GitHub API 生成 Commit 的方法。通常我们会使用 Git 客户端 Commit 然后 Push 到 GitHub,但 GitHub 为我们提供了相关 API,可以直接通过 API 更新仓库。

要搞清楚整个更新流程,需要先理解 Git 的数据结构。如下图所示,Git 会使用 Ref、Commit、Tree、Blob 等单位管理 Commit 和文件。 所以要生成一个新的 Commit,需要从树状结构的叶到根按顺序生成,换句话说就是:Blob→Tree→Commit→Ref。

使用 GitHub API 提交文件有以下步骤。虽然对于第一次接触的新手来说可能会有点复杂,但是理清关系之后思路便会很清晰了。

  1. 获取 Ref:Ref 指 Git 的引用。如果要发起 Commit,必须知道你的 Commit 要提交到什么地方去(Commit 是一个接一个的链状关系,所以需要知道上一个 Commit 的信息),这一步做的就是这件事。
  2. 获取 Commit:用于获取当前 Commit 的 tree 的 sha。
  3. 生成 Blob:相当于正常本地提交的 add 操作。
  4. 生成 Tree:构建一个新的 tree。这里需要用到的参数 base_tree 就是来自第二步的 Commit 信息。
  5. 生成 Commit:提交你的 tree。至此已经完成提交。
  6. 更新 Ref:使 master 的指针指到你最新提交的版本。

注意:访问 POST 方法的接口必须带 token,虽然 GET 可以不带,但是会限制访问频率,所以建议都带上。相关文档:https://developer.github.com/v3/#authentication

1. 获取 Ref

1.1 文档地址

https://developer.github.com/v3/git/refs/#get-a-reference

1.2 请求地址

GET https://api.github.com/repos/ssshooter/test/git/refs/heads/master

1.3 返回数据

{

"ref": "refs/heads/master",

"node_id": "MDM6UmVmMTY0Nzk4NDczOm1hc3Rlcg==",

"url": "https://api.github.com/repos/ssshooter/test/git/refs/heads/master",

"object": {

"sha": "cda66de943082033f4b761639df77728d7bca4f0",

"type": "commit",

"url": "https://api.github.com/repos/ssshooter/test/git/commits/cda66de943082033f4b761639df77728d7bca4f0"

}

}

2. 获取 Commit

2.1 文档地址

https://developer.github.com/v3/git/commits/#get-a-commit

2.2 请求地址

GET https://api.github.com/repos/ssshooter/test/git/commits/cda66de943082033f4b761639df77728d7bca4f0

2.3 返回数据

{

"sha": "cda66de943082033f4b761639df77728d7bca4f0",

"node_id": "MDY6Q29tbWl0MTY0Nzk4NDczOmNkYTY2ZGU5NDMwODIwMzNmNGI3NjE2MzlkZjc3NzI4ZDdiY2E0ZjA=",

"url": "https://api.github.com/repos/ssshooter/test/git/commits/cda66de943082033f4b761639df77728d7bca4f0",

"html_url": "https://github.com/ssshooter/test/commit/cda66de943082033f4b761639df77728d7bca4f0",

"author": {

"name": "DeJavuJo",

"email": "ssshooterx@gmail.com",

"date": "2019-01-09T06:02:07Z"

},

"committer": {

"name": "GitHub",

"email": "noreply@github.com",

"date": "2019-01-09T06:02:07Z"

},

"tree": {

"sha": "d7a57d28ace0db12773c7d70675f94a48da6421f",

"url": "https://api.github.com/repos/ssshooter/test/git/trees/d7a57d28ace0db12773c7d70675f94a48da6421f"

},

"message": "Create readme.md",

"parents": [],

"verification": {

"verified": true,

"reason": "valid",

"signature": "-----BEGIN PGP SIGNATURE-----\n\nwsBcBAABCAAQBQJcNY5fCRBK7hj4Ov3rIwAAdHIIABh8I89hATqg1mSYtpx1aY\nJt/woDobMO7FGE5qXO0NNrCMqwF6mdPJOMMMZvVWF1ULTm8ZJ52GAh5xAnPMZEnQ\n8tTjj/Qc0eZCm5B1xO66rgx+7eKkeGUPJj5bX7Lf0i9Se70Ff0jaCdH94RgiSL2d\nclDLhNyM4u6AH//k7S3Ud1O6ezXd4+99381Xa331PDLhJttUAbRFRCThszbcxRUT\nPvyhPNvXB5ug4J+tAMaZJvZEaED0c1k2Yx1+TYkLvPjOlqXvqaDVpMZieluD5l+f\nu13NAoCnLfBe0Skak/8MxRDbMcJYNW78ll60HAa6jJtElD8Vkek8WoVAZ8p3iIE=\n=xI87\n-----END PGP SIGNATURE-----\n",

"payload": "tree d7a57d28ace0db12773c7d70675f94a48da6421f\nauthor DeJavuJo 1547013727 +0800\ncommitter GitHub 1547013727 +0800\n\nCreate readme.md"

}

}

3. 生成 Blob

3.1 文档地址

https://developer.github.com/v3/git/blobs/#create-a-blob

3.2 请求地址

POST https://api.github.com/repos/ssshooter/test/git/blobs

3.3 请求参数

{

"content": "Content of the blob",

"encoding": "utf-8"

}

3.4 返回数据

{

"sha": "929246f65aab4d636cb229c790f966afc332c124",

"url": "https://api.github.com/repos/ssshooter/test/git/blobs/929246f65aab4d636cb229c790f966afc332c124"

}

4. 生成 tree

4.1 文档地址

https://developer.github.com/v3/git/trees/#create-a-tree

4.2 请求地址

POST https://api.github.com/repos/ssshooter/test/git/trees

4.3 请求参数

注意:tree.path 可以写深层目录,如  deep/deep/newFile.md(前面不用写斜杠)

{

"base_tree": "d7a57d28ace0db12773c7d70675f94a48da6421f", // commit tree 的 sha

"tree": [

{

"path": "apiCommitFile.md", // 文件路径

"mode": "100644", // 类型,详情看文档

"type": "blob",

"sha": "929246f65aab4d636cb229c790f966afc332c124" // 刚才生成的 blob 的 sha

}

]

}

4.4 返回数据

{

"sha": "2b3a65095ceb7cf4425f52d59ca5974d826cff80",

"url": "https://api.github.com/repos/ssshooter/test/git/trees/2b3a65095ceb7cf4425f52d59ca5974d826cff80",

"tree": [

{

"path": "readme.md",

"mode": "100644",

"type": "blob",

"sha": "b1b716105590454bfc4c0247f193a04088f39c7f",

"size": 5,

"url": "https://api.github.com/repos/ssshooter/test/git/blobs/b1b716105590454bfc4c0247f193a04088f39c7f"

},

{

"path": "tree",

"mode": "040000",

"type": "tree",

"sha": "91d8d59147e395effaeacd01c9d8553b37cf77c5",

"url": "https://api.github.com/repos/ssshooter/test/git/trees/91d8d59147e395effaeacd01c9d8553b37cf77c5"

}

],

"truncated": false

}

5. 生成 Commit

5.1 文档地址

https://developer.github.com/v3/git/commits/#create-a-commit

5.2 请求地址

POST https://api.github.com/repos/ssshooter/test/git/commits

5.3 请求参数

{

"message": "a Commit with GitHub api",

"parents": ["cda66de943082033f4b761639df77728d7bca4f0"],

"tree": "2b3a65095ceb7cf4425f52d59ca5974d826cff80"

}

5.4 返回数据

{

"sha": "45c58a9358b67fc81e4034cb36c5196d791686ef",

"node_id": "MDY6Q29tbWl0MTY0Nzk4NDczOjQ1YzU4YTkzNThiNjdmYzgxZTQwMzRjYjM2YzUxOTZkNzkxNjg2ZWY=",

"url": "https://api.github.com/repos/ssshooter/test/git/commits/45c58a9358b67fc81e4034cb36c5196d791686ef",

"html_url": "https://github.com/ssshooter/test/commit/45c58a9358b67fc81e4034cb36c5196d791686ef",

"author": {

"name": "ssshooter",

"email": "ssshooterx@gmail.com",

"date": "2019-01-09T10:24:10Z"

},

"committer": {

"name": "ssshooter",

"email": "ssshooterx@gmail.com",

"date": "2019-01-09T10:24:10Z"

},

"tree": {

"sha": "2b3a65095ceb7cf4425f52d59ca5974d826cff80",

"url": "https://api.github.com/repos/ssshooter/test/git/trees/2b3a65095ceb7cf4425f52d59ca5974d826cff80"

},

"message": "a Commit with GitHub api",

"parents": [

{

"sha": "cda66de943082033f4b761639df77728d7bca4f0",

"url": "https://api.github.com/repos/ssshooter/test/git/commits/cda66de943082033f4b761639df77728d7bca4f0",

"html_url": "https://github.com/ssshooter/test/commit/cda66de943082033f4b761639df77728d7bca4f0"

}

],

"verification": {

"verified": false,

"reason": "unsigned",

"signature": null,

"payload": null

}

}

6. 更新 Ref

6.1 文档地址

https://developer.github.com/v3/git/refs/#update-a-reference

6.2 请求地址

https://api.github.com/repos/ssshooter/test/git/refs/heads/master

6.3 请求参数

{

"sha": "45c58a9358b67fc81e4034cb36c5196d791686ef",

"force": true

}

6.4 返回数据

{

"ref": "refs/heads/master",

"node_id": "MDM6UmVmMTY0Nzk4NDczOm1hc3Rlcg==",

"url": "https://api.github.com/repos/ssshooter/test/git/refs/heads/master",

"object": {

"sha": "45c58a9358b67fc81e4034cb36c5196d791686ef",

"type": "commit",

"url": "https://api.github.com/repos/ssshooter/test/git/commits/45c58a9358b67fc81e4034cb36c5196d791686ef"

}

}

7. node.js 实践代码

var updateGitHubRes = function (blob, path) {

var commitSha;

var commitTreeSha;

return getRef()

.then(({ data }) => {

commitSha = data.object.sha;

return getCommit(commitSha);

})

.then(({ data }) => {

commitTreeSha = data.tree.sha;

return createBlob(blob);

})

.then(({ data }) => {

var blobSha = data.sha;

return createTree(commitTreeSha, path, blobSha);

})

.then(({ data }) => {

var treeSha = data.sha;

return createCommit(commitSha, treeSha);

})

.then(({ data }) => {

var newCommitSha = data.sha;

return updataRef(newCommitSha);

})

.catch((err) => {

console.log(err);

});

};

var getRef = function () {

return axios.get(`/${owner}/${repo}/git/refs/heads/master`);

};

var getCommit = function (commitSha) {

return axios.get(`/${owner}/${repo}/git/commits/${commitSha}`);

};

var createBlob = function (content) {

return axios.post(`/${owner}/${repo}/git/blobs`, {

content,

encoding: "utf-8",

});

};

var createTree = function (base_tree, path, sha) {

return axios.post(`/${owner}/${repo}/git/trees`, {

base_tree, // commit tree 的 sha

tree: [

{

path, // 文件路径

mode: "100644", // 类型,详情看文档

type: "blob",

sha, // 刚才生成的 blob 的 sha

},

],

});

};

var createCommit = function (parentCommitSha, tree, message = "update post") {

return axios.post(`/${owner}/${repo}/git/commits`, {

message,

parents: [parentCommitSha],

tree,

});

};

var updataRef = function (newCommitSha) {

return axios.post(`/${owner}/${repo}/git/refs/heads/master`, {

sha: newCommitSha,

force: true,

});

};

参考文献