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One Click to Optimize Images, Create Repo and Making Commit

Continuing from last post, I have completed my feature that produces optimized images, create a remote repository and make a commit with the files. My PR may be updated, but I think the change would not be so big from now.

So the main challenge was how I can make one click to create a repo and make a commit. I tried to use library. I'm not sure what I did wrong, but it didn't read the parameters that I passed. But GitHub API version works for me. And the post How to push files programatically to a repository using Octokit with Typescript was a huge help for me. My version is not so different from this post except that I use JavaScript and create multiple blobs in the middle of the process.

First I create a remote repo with createRepo function below.

const createRepo = async (octokit, username, repoName) => {
  try {
      name: repoName ? repoName : generateUniqueName(username),
      description: 'Your repository generated using my-photohub',
      private: false,
      auto_init: true,
    return true;
  } catch (err) {
    return false;
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Then, I produce optimized images with compressor.js.

const compressImage = (file, option) => {
  return new Promise((resolve, reject) => {
    new Compressor(file, {
      width: option.width,
      quality: 0.6,
      success: (result) => {
        const fileName =
\.[^/.]+$/, '') +
          '_' +
          option.width +
          '.' +
          option.mimeType.substring(option.mimeType.indexOf('/') + 1);
        resolve(new File([result], fileName, { type: option.mimeType }));
      error: (err) => {

export const createOptimizedImages = async (originalImages) => {
  if (!originalImages) {

  let compressFilesPromises = [];
  compressorOptions.forEach((option) => {
    for (const image of originalImages) {
      compressFilesPromises.push(compressImage(image, option));

  return Promise.all(compressFilesPromises);
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You can change image quality or pass different options. I set customized mimeType and width by passing option parameter here. You can find more usages from compressor.js original documentation.

Then I need to create a blob from each file with the function below.

const createBlobForFile = async (octokit, username, repoName, files) => {
  let blobDataPromises = [];
  for (const file of files) {
    let reader = new FileReader();
    await reader.readAsDataURL(file);
    const promise = new Promise((resolve, reject) => {
      reader.onload = async () => {
        const base64Data = reader.result;
        const blobData = octokit.request(`POST /repos/${username}/${repoName}/git/blobs`, {
          owner: username,
          repo: repoName,
          content: base64Data,
      reader.onerror = reject;
  return Promise.all(blobDataPromises);
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So this function returns an array of blob object in the same order from files.

NOTE: You can also use BlobURL as DataURL is very long and it has a length limit.

const imageBuffer = reader.result;
const byteArray = new Uint8Array(imageBuffer);
const blob = new Blob([byteArray]);
const BlobURL = URL.createObjectURL(blob);

In the blob, it doesn't have a file name that I can use as a path in next function. So I added getPathNamesFromFile().

const getPathNamesFromFile = (convertedFiles) => {
  let pathNames = [];
  for (const file of convertedFiles) {
  return pathNames;
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Next step is that I need to get current existing commit from the repo that I just created so that I can add a new commit as a child. Here's the function.

const createNewCommit = async (
) =>
    await octokit.request(`POST /repos/${username}/${repoName}/git/commits`, {
      owner: username,
      repo: repoName,
      message: message,
      tree: currentTreeSha,
      parents: [currentCommitSha],
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The function is pretty obvious as if I'm making an actual commit. Then, I need to create trees to add. You can find details of git tree object here. Basically blob is a file and tree is a directory in git. You can check your git folder with this command.

❯ git cat-file -p main^{tree}                                                ─╯
040000 tree f808c5b1a9eaa36928f49ac82b8b2ed85c53af45    .vscode
100644 blob 3ee245e88d83084868e58ba369200acc8354f9df
100644 blob 8202e8c8292a2681114b67099e5f47c5aa0e13e4    package.json
040000 tree 2ce2a0fdb03a853cc6c855ebc46865cd20d3afaf    public
040000 tree e3ef837d95be8981e826c7ad683101475f2b6528    src
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And you would have noticed numbers in front of tree and blob. This number is an associated mode with the file. 100644 means a normal file. You would have figured 040000 is a directory. 100755 is an executable file and 120000 is a symbolic link.

And the last step is to set the branch to this new commit.

const setBranchToCommit = (octokit, username, repoName, branch = `main`, commitSha) =>
  octokit.request(`PATCH /repos/${username}/${repoName}/git/refs/heads/${branch}`, {
    owner: username,
    repo: repoName,
    ref: `heads/${branch}`,
    sha: commitSha,
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I spent many days to figure this out. But in the end, I was so happy to see my code working as intended. I was on the issue that my array of promises in createBlobForFile() returned an empty array for many hours. I could have fixed the problem if I tried to think more rational about the behaviour and root cause. I was adding each promise inside reader.onload. So the outer function just bypassed the code block and returned an empty array immediately. It was a lot of trials and learning. Moreover, I'm so glad that I set very fundamental of this app.

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