javascript - 'img-src' was not explicitly set, so 'default-src' is used as a fallback

Question

Here is my Content-Security-Policy in index.html

<meta http-equiv="Content-Security-Policy" content="default-src 'self' http://example.com">

Now i am dynamically setting img src of <img id="updateProfilePicPreview" class="profilPicPreview" src="" /> as

  var smallImage = document.getElementById('updateProfilePicPreview');
  smallImage.style.display = 'block';
  smallImage.src = "data:image/jpeg;base64," + imageData;

It shows

Refused to load the image 'data:image/jpeg;base64,/9j/4AAQSkZJRgABAQAAAQABAAD/2wBDACgcHiMeGSgjISMtKygw…p+tB/yaKKAIi2TSfjRRVCJFOyIk96rE5NFFDGgoooqBhRRRQA9elIDg5oopgIc+lFFFAH/2Q==' because it violates the following Content Security Policy directive: "default-src 'self' http://example.com". Note that 'img-src' was not explicitly set, so 'default-src' is used as a fallback.

So how can i enable setting img src dynamically ?

I was following this example from cordova page:

var pictureSource;   // picture source
var destinationType; // sets the format of returned value

// Wait for device API libraries to load
//
document.addEventListener("deviceready",onDeviceReady,false);

// device APIs are available
//
function onDeviceReady() {
    pictureSource=navigator.camera.PictureSourceType;
    destinationType=navigator.camera.DestinationType;
}

// Called when a photo is successfully retrieved
//
function onPhotoDataSuccess(imageData) {
  // Uncomment to view the base64-encoded image data
  // console.log(imageData);

  // Get image handle
  //
  var smallImage = document.getElementById('smallImage');

  // Unhide image elements
  //
  smallImage.style.display = 'block';

  // Show the captured photo
  // The in-line CSS rules are used to resize the image
  //
  smallImage.src = "data:image/jpeg;base64," + imageData;
}

// Called when a photo is successfully retrieved
//
function onPhotoURISuccess(imageURI) {
  // Uncomment to view the image file URI
  // console.log(imageURI);

  // Get image handle
  //
  var largeImage = document.getElementById('largeImage');

  // Unhide image elements
  //
  largeImage.style.display = 'block';

  // Show the captured photo
  // The in-line CSS rules are used to resize the image
  //
  largeImage.src = imageURI;
}

// A button will call this function
//
function capturePhoto() {
  // Take picture using device camera and retrieve image as base64-encoded string
  navigator.camera.getPicture(onPhotoDataSuccess, onFail, { quality: 50,
    destinationType: destinationType.DATA_URL });
}

// A button will call this function
//
function capturePhotoEdit() {
  // Take picture using device camera, allow edit, and retrieve image as base64-encoded string
  navigator.camera.getPicture(onPhotoDataSuccess, onFail, { quality: 20, allowEdit: true,
    destinationType: destinationType.DATA_URL });
}

// A button will call this function
//
function getPhoto(source) {
  // Retrieve image file location from specified source
  navigator.camera.getPicture(onPhotoURISuccess, onFail, { quality: 50,
    destinationType: destinationType.FILE_URI,
    sourceType: source });
}

// Called if something bad happens.
//
function onFail(message) {
  alert('Failed because: ' + message);
}

Answer 1

So how can i enable setting img src dynamically ?

The problem is not setting the src, the problem is setting the src to a data: scheme URI.

Add data: to the list of things allowed by the content security policy. Either for the default-src or you could define a separate img-src.

In the example below, I have added img-src 'self' data:; to the start of the meta tag in the index.html file.

<meta http-equiv="Content-Security-Policy" content="img-src 'self' data:; default-src 'self' http://XX.XX.XX.XX:8084/mypp/">