index.js

/* global tus Camera */

var upload = null;
var uploadIsRunning = false;
var file = null;

var uploadButton = document.querySelector("#js-upload-button");
var fileInput = document.querySelector("#js-upload-file");
var fileLink = document.querySelector("#js-file-link");
var progressBar = document.querySelector("#js-upload-progress");
var progressText = document.querySelector("#js-upload-progress-text");
var uploadLink = document.querySelector("#js-upload-link");

fileInput.addEventListener("click", openFilePicker);

function resetUpload() {
  if (upload) {
    upload.abort();
    upload = null;
  }

  uploadButton.textContent = "Start Upload";
  uploadLink.textContent = "not available yet";
  progressText.textContent = "";
  progressBar.removeAttribute("value");
}

uploadButton.addEventListener("click", toggleUpload);

function openFilePicker() {
  resetUpload();

  var options = {
    // Camera is a global cordova-specific object used for configuring camera access.
    // See https://cordova.apache.org/docs/en/latest/reference/cordova-plugin-camera/#module_Camera
    destinationType: Camera.DestinationType.FILE_URI,
    sourceType: Camera.PictureSourceType.PHOTOLIBRARY,
    encodingType: Camera.EncodingType.JPEG,
    mediaType: Camera.MediaType.PICTURE,
    // Allow simple editing of image before selection.
    allowEdit: true,
    // Rotate the image to correct for the orientation of the device during
    // capture to fix orientation quirks on Android
    correctOrientation: true
  };

  navigator.camera.getPicture(getFileEntry, function (error) {
    window.alert("Unable to obtain picture: " + error);
  }, options);
}

function getFileEntry(imgUri) {
  window.resolveLocalFileSystemURL(imgUri, function success(fileEntry) {
    fileEntry.file(function (fileObj) {
      file = fileObj;
      fileLink.textContent = file.name;
    });
  }, function (error) {
    window.alert("Could not create FileEntry: " + error);
  });
}

function toggleUpload() {
  if (!upload) {
    if (!file) return;

    var options = {
      endpoint: "https://master.tus.io/files/",
      resume: false,
      retryDelays: [0, 1000, 3000, 5000],
      metadata: {
        filename: file.name,
        filetype: file.type
      },
      onError: function (error) {
        if (error.originalRequest) {
          if (window.confirm("Failed because: " + error + "\nDo you want to retry?")) {
            upload.start();
            uploadIsRunning = true;
            return;
          }
        } else {
          window.alert("Failed because: " + error);
        }

        resetUpload();
      },
      onProgress: function (bytesUploaded, bytesTotal) {
        var progress = bytesUploaded / bytesTotal;
        var percentage = (progress * 100).toFixed(2) + "%";
        progressBar.value = progress;
        progressText.textContent = percentage;
      },
      onSuccess: function () {
        var anchor = document.createElement("a");
        anchor.textContent = "Download " + upload.file.name + " (" + upload.file.size + " bytes)";
        anchor.target = "_blank";
        anchor.href = upload.url;

        uploadLink.innerHTML = "";
        uploadLink.appendChild(anchor);
      }
    };

    upload = new tus.Upload(file, options);

    upload.start();
    uploadIsRunning = true;
    uploadButton.textContent = "Pause Upload";

  } else {
    if (uploadIsRunning) {
      upload.abort();
      uploadButton.textContent = "Resume Upload";
      uploadIsRunning = false;
    } else {
      upload.start();
      uploadButton.textContent = "Pause Upload";
      uploadIsRunning = true;
    }
  }
}