Go to first commit of GitHub repo

main.js

async function goToFirstCommit(owner, repo) {
    const headers = {
        "Accept": "application/vnd.github.v3+json",
        // Optional: Add authorization if you hit the rate limit (use a personal access token)
        // "Authorization": "Bearer YOUR_GITHUB_TOKEN"
    };

    const repoInfo = await fetch(`https://api.github.com/repos/${owner}/${repo}`, { headers });
    const repoData = await repoInfo.json();
    const defaultBranch = repoData.default_branch;

    const branchInfo = await fetch(`https://api.github.com/repos/${owner}/${repo}/branches/${defaultBranch}`, { headers });
    const branchData = await branchInfo.json();
    const latestCommitSha = branchData.commit.sha;

    // Step 2: Get the total number of commits in the default branch using the API for commits count
    const commitsInfo = await fetch(`https://api.github.com/repos/${owner}/${repo}/commits?sha=${defaultBranch}&per_page=1`, { headers });
    const linkHeader = commitsInfo.headers.get("link");

    // The "last" page link in the Link header contains the total number of commits
    let totalCommits;
    if (linkHeader) {
        const lastPageMatch = linkHeader.match(/&page=(\d+)>; rel="last"/);
        totalCommits = lastPageMatch ? lastPageMatch[1] : 1;
    } else {
        // If there's no pagination, it means there is only one page of commits
        totalCommits = 1;
    }

    console.log(`Total commits in ${defaultBranch} branch: ${totalCommits}`);

    if (totalCommits != 1) {
        const firstCommitURL = `https://github.com/${owner}/${repo}/commits/${defaultBranch}/?after=${latestCommitSha}+${totalCommits - 36}`
        console.log(`First commit URL is ${firstCommitURL}`)
        window.location.href = firstCommitURL;
    }
}

async function main() {
    const currentUrl = window.location.href;

    const regex = /https:\/\/github\.com\/([^\/]+)\/([^\/]+)/;
    const match = currentUrl.match(regex);

    if (match) {
        const owner = match[1];
        const repo = match[2];

        console.log(`Owner: ${owner}`);
        console.log(`Repository: ${repo}`);

        await goToFirstCommit(owner, repo);
    } else {
        console.log("Not on a GitHub repository page.");
    }
}

main()

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