index.js

const core = require('@actions/core');
const github = require('@actions/github');

const run = async () => {
    // Get octokit
    const token = core.getInput('token', { required: true });
    const is_oauth_token = core.getInput('is-oauth-token');

    const githubToken = is_oauth_token ? '' : token;
    const oauthToken = is_oauth_token ? token : '';
    const client = github.getOctokit(githubToken, {auth: oauthToken});

    // Get issue and pr message
    const issueMessage = core.getInput('issue-message');
    const prMessage = core.getInput('pr-message');

    if (!issueMessage && !prMessage) {
        throw new Error(
          'Action must have at least one of issue-message or pr-message set'
        );
    }

    const context = github.context;

    // Do nothing if `action` is not `opened`.
    if (context.payload.action !== 'opened') {
        console.log('No issue or PR was opened, skipping');
        return;
    }

    // Do nothing if its not a pr or issue
    const isIssue = !!context.payload.issue;
    if (!isIssue && !context.payload.pull_request) {
      console.log(
        'The event that triggered this action was not a pull request or issue, skipping.'
      );
      return;
    }

    // Do nothing if no message set for this type of contribution
    const message = isIssue ? issueMessage : prMessage;
    if (!message) {
        console.log('No message provided for this type of contribution');
        return;
    }


    // Get sender, repo and issue/pr info
    if (!context.payload.sender) {
      throw new Error('Internal error, no sender provided by GitHub');
    }
    const sender = context.payload.sender.login;

    // Both issue and pr_number (or payload number, as applicable)
    // can be found  in `context.issue`.
    const {owner, repo, number} = context.issue;


    // Do nothing if its not their first contribution
    console.log('Checking if it is the user\'s first contribution');

    let firstContribution = false;
    if (isIssue) {
        firstContribution = await isFirstIssue(client, owner, repo, sender, number);
    } else {
        firstContribution = await isFirstPull(client, owner, repo, sender, number);
    }
    if (!firstContribution) {
      console.log('Not the user\'s first contribution');
      return;
    }

    // Prepare the final message
    const final_message = message.replace(/@contributor_name/g, `@${sender}`);


    // To create a comment on a pull request, we hit the issue endpoint only.
    // See: https://octokit.github.io/rest.js/v18#pulls-create-review-comment
    // 
    // So, from here, both issue and pull will be considered as `issue`.

    const issueType = isIssue ? 'issue' : 'pull request';
    // Add a comment to the appropriate place
    console.log(`Adding message: ${final_message} to ${issueType} ${number}`);

    // Add comment (greeting) to issue/PR
    try {
        await client.issues.createComment({
            owner,
            repo,
            issue_number: number,
            body: final_message
        });
    } catch (error) {
        core.setFailed(error.message);
    }
};


async function isFirstIssue(client, owner, repo, sender, curIssueNumber) {
    const {status, data: issues} = await client.issues.listForRepo({
      owner,
      repo,
      creator: sender,
      state: 'all'
    });
  
    if (status !== 200) {
      throw new Error(`Received unexpected API status code ${status}`);
    }
  
    if (issues.length === 0) {
      return true;
    }
  
    for (const issue of issues) {
      if (issue.number < curIssueNumber && !issue.pull_request) {
        return false;
      }
    }

    return true;
}

// No way to filter pulls by creator
async function isFirstPull(client, owner, repo, sender, curPullNumber, page = 1) {
    // Provide console output if we loop for a while.
    console.log(`Checking for first pull (at page ${page})`);
    const {status, data: pulls} = await client.pulls.list({
      owner,
      repo,
      per_page: 100,
      page: page,
      state: 'all'
    });
  
    if (status !== 200) {
      throw new Error(`Received unexpected API status code ${status}`);
    }
  
    if (pulls.length === 0) {
      return true;
    }
  
    for (const pull of pulls) {
      const login = pull.user.login;
      if (login === sender && pull.number < curPullNumber) {
        return false;
      }
    }

    return await isFirstPull(client, owner, repo, sender, curPullNumber, page + 1);
}


// Run the script
try {
    run();
} catch (error) {
    core.setFailed(error.message);
}