replace_twitter_shortlinks_on_mastodon.js

// USE AT YOUR OWN RISK
// This is a JavaScript script edits your statuses/toots
// It's pretty rudimentary and doesn't account for all possible cases
//
// This script will iterate through a list of Mastodon statuses,
// searching for Twitter t.co shortlinks and replacing them with their actual targets.
// When a t.co link is found, this script makes a web request to find its target and updates it.
// It will also convert all http:// links to https://
//
// While running, this script will output progress to the console so you can check for erros
// Any time a status is updated, it will open the status in a new tab so you can verify

// Populate these values:
const statusIds = ["12345678912345678"]; // Array of status IDs extracted from Mastodon archive
const BASE_URL = 'https://example.com'; // URL for your Mastodon server
const USERNAME = '@example'; // Your Mastdon username with the '@'
const TOKEN = ''; // Mastodon API token

const TCO_REGEX = /t\.co\/[a-zA-Z0-9\-\.]*/g;
const parser = new DOMParser();
const req = new XMLHttpRequest();

// Strip HTML for a string
// Mastodon returns statuses as HTML, which needs to be stripped
// because Mastodon's PUT endpoint takes a plaintext string
function strip(html) {
    let doc = new DOMParser().parseFromString(html, 'text/html');
    return doc.body.textContent || "";
}

// Make a web request to find a t.co link's target
async function resolveTcoUrl(url) {
    return new Promise(function (resolve) {
        url = url.replace('?amp=1', '');

        req.open("GET", url, true);
        req.send();
        req.onreadystatechange = function () {
            if (this.readyState == 4) {
                var responseHTML = parser.parseFromString(req.responseText, 'text/html');
                resolve(responseHTML.getElementsByTagName('title')[0].innerHTML);
            }
        };
    });
};

// Make a GET request
async function get(url) {
    const response = await fetch(url, {
        method: 'GET',
        headers: {
            'Content-type': 'application/json',
            'Authorization': 'Bearer ' + TOKEN
        }
    });
    return response;
};

// Make a PUT request
async function put(url, data) {
    const response = await fetch(url, {
        method: 'PUT',
        headers: {
            'Content-type': 'application/json',
            'Authorization': 'Bearer ' + TOKEN
        },
        body: JSON.stringify(data)
    });
    return response;
};

// Sleep function
const sleep = ms => new Promise(resolve => setTimeout(resolve, ms));

async function main() {
    (async () => {
        for (let i = 0; i < statusIds.length; i++) {
            // Get status:
            var status = await get(BASE_URL + '/api/v1/statuses/' + statusIds[i]);
            var statusResponse = await status.json();
            console.log('Got Toot ' + statusIds[i]);

            // Sleep to avoid rate limiting:
            await sleep(5000);

            // If status includes a t.co link, start the replacement
            if (statusResponse.content.includes('t.co/')) {
                var newContent = strip(statusResponse.content);
                console.log('Original status: ' + newContent)
                var results = [...statusResponse.content.matchAll(TCO_REGEX)];
                for (let j = 0; j < results.length; j++) {
                    var newUrl = await resolveTcoUrl('https://' + results[j]);
                    
                    // Replace t.co link with destination link
                    newContent = newContent.replaceAll(results[j], newUrl.replace(/^https?:\/\//, ''));
                    
                    // Replace http:// with https://
                    newContent = newContent.replaceAll('http://', 'https://');
                }
                console.log('=====================');
                console.log('Edited status: ' + newContent);
                console.log(statusResponse);
                
                // Attach existing media for the PUT
                // Making a PUT without attaching any existing media will remove that media from the status
                if (statusResponse.media_attachments.length > 0) {
                    var update = await put(BASE_URL + '/api/v1/statuses/' + statusIds[i], { 'status': newContent, 'media_ids': statusResponse.media_attachments.map(function (el) { return el.id; }) });
                } else {
                    var update = await put(BASE_URL + '/api/v1/statuses/' + statusIds[i], { 'status': newContent });
                }
                await sleep(3000);
                var updateResponse = await update.json();
                console.log(updateResponse);
                
                // Open updated status in new tab, so you can double-check for any errors:
                window.open(BASE_URL + '/' + USERNAME + '/' + statusIds[i], '_blank');
            }
        }
    })();
}

main();