Image Max URL

Website (https://qsniyg.github.io/maxurl/), userscript (https://greasyfork.org/en/scripts/36662-image-max-url) and reddit bot (/u/MaxImageBot) to redirect images to larger/original versions.

For users

Either use the website or install the userscript, which redirects to larger/original versions of images when you open them in a new tab.

For developers

The userscript also functions as a node module.

var maximage = require('./userscript.user.js');

maximage(smallimage, {
  // If set to false, it will return only the URL if there aren't any special properties
  fill_object: true,

  // Maximum amount of times it should be run.
  //  Recommended to be at least 5
  iterations: 200,

  // Whether or not to store to, and use an internal cache
  use_cache: true,

  // Helper function to perform HTTP requests, used for sites like Flickr
  //  The API is expected to be like GM_xmlHTTPRequest's API.
  do_request: function(options) {
    // options = {
    //   url: "",
    //   method: "GET",
    //   headers: {}, // If a header is null or "", don't include that header
    //   onload: function(resp) {
    //     // resp is expected to be XMLHttpRequest-like object, implementing these fields:
    //     //   finalUrl
    //     //   readyState
    //     //   responseText
    //     //   status
    //   }
    // }
  },

  // Callback
  cb: function(result) {
    if (!result)
      return;

    if (result.length === 1 && result[0].url === smallimage) {
       // No larger image was found
       return;
    }

    for (var i = 0; i < result.length; i++) {
      // Do something with the object
    }
  }
});

The result is a list of objects that contain properties that may be useful in using the returned image(s):

{
  // Array or String, see code example above
  url: null,

  // Whether it's expected that it will always work or not.
  //  Don't rely on this value if you don't have to
  always_ok: false,

  // Whether or not the server supports a HEAD request.
  can_head: true,

  // Whether or not the server might return the wrong Content-Type header in the HEAD request
  head_wrong_contenttype: false,

  // Whether or not the server might return the wrong Content-Length header in the HEAD request
  head_wrong_contentlength: false,

  // This is used in the return value of the exported function.
  //  If you're using a callback (as shown in the code example above),
  /   this value will always be false
  waiting: false,

  // Whether or not the returned URL is expected to redirect to another URL
  redirects: false,

  // Whether or not this URL should be used
  bad: false,

  // Headers required to view the returned URL
  //  If a header is null, don't include that header.
  headers: {}
}