A bookmarklet to download all images from a user on Instagram

downloadInstagramImages.js

/*
 * Bookmarklet to download all IG images for the current account page.
 * Use https://katanya.co.uk/labs/bookmarklet-generator to generate the bookmarklet.
 *
 * SEE: https://www.instagram.com/web/search/topsearch/?query=casetify
 * SEE: https://www.instagram.com/graphql/query/?query_id=17888483320059182&variables={"id":"6662673","first":50,after:"QVFEaEJRR0tiTXpVUVV5ZVlfQktDUFJYNUpRWlhOMktKbWZXWEh4cHNCSFV2ZDA5RVBaUzFfWmxVOWlaMHNfVU1wNTQ1dFVXZlVoT05oUzRVVHYyNVBZMQ=="}
 */

(async function () {
    let userId = "";
    let imageUrls = [];
    let cursor = "";

    // Get the user's ID
    const getUserId = async () => {
        // Try to get username from the page
        let username = document.title.match(/@(.+?)\b/);
        if (username && username[1]) {
            username = username[1];
        }

        // No username found on page, so ask for it
        if (!username) {
            username = prompt("Enter username (you must be on instagram.com):");
        }

        // Serach IG for the username
        const response = await fetch(
            `https://www.instagram.com/web/search/topsearch/?query=${username}`,
            { mode: "cors" }
        );
        const data = await response.json();

        // Get the user's ID
        userId = data.users[0].user.pk;
    };

    // Using the IG GQL API, get the user's image URLs
    const getImageUrls = async (cursor = "") => {
        const vars = {
            id: userId,
            first: 50,
            after: cursor,
        };

        const response = await fetch(
            `https://www.instagram.com/graphql/query/?query_id=17888483320059182&variables=${JSON.stringify(
                vars
            )}`,
            {
                mode: "cors",
            }
        );
        const data = await response.json();
        const media = data.data.user.edge_owner_to_timeline_media;

        // Get any new image URL
        media.edges.forEach((edge) => {
            imageUrls.push(edge.node.display_url);
        });

        // If more pages, loop back around
        if (media.page_info.has_next_page) {
            cursor = media.page_info.end_cursor;
        } else {
            cursor = false;
        }

        return cursor;
    };

    // Download the image
    function forceDownload(blob, filename) {
        var a = document.createElement("a");
        a.download = filename;
        a.href = blob;
        a.click();
    }

    // Current blob size limit is around 500MB for browsers
    async function downloadResource(url, filename) {
        if (!filename) filename = url.split("\\").pop().split("/").pop();

        try {
            const response = await fetch(url, {
                headers: new Headers({
                    Origin: location.origin,
                }),
                mode: "cors",
            });
            const blob = await response.blob();

            let blobUrl = window.URL.createObjectURL(blob);
            forceDownload(blobUrl, filename);
        } catch (e) {
            console.error(e);
        }
    }

    console.log("Downloading images...");

    // Get the user's ID
    await getUserId();

    // Get as many images as requested
    let amount = prompt("How many images to download?");
    amount = parseInt(amount);

    cursor = await getImageUrls();
    while (cursor) {
        if (imageUrls.length > amount) {
            break;
        }
        cursor = await getImageUrls(cursor);
    }

    // Trim the found amount to match requested amount (as we will be loading pages of images above)
    imageUrls = imageUrls.slice(0, amount);

    // Log out total found
    console.log(
        `${imageUrls.length} images found, downloading them all now...`
    );

    // Now download all images
    try {
        imageUrls.forEach(function (url) {
            downloadResource(url);
        });
    } catch (e) {
        alert("Download failed.");
        console.log("Download failed.", e);
    }

    console.log("Finished!");
}.call(window));