Remove specific URLs from the cache

Author: paulprins

README.md

@@ -48,9 +48,12 @@ These images would later be automatically placed due to element or parent bindin
 If you need to use an image in your inline css, or in another context where you just need the encoded string you should use this function. It will return the encoded string if it has already been cached, or it will return the default (if that is already encoded), or null. This will not fetch the URL.
 
 ### Drop the cached images  
-`$.fn.cacheImages.drop();`  
+`$.fn.cacheImages.drop( *url*, *storagePrefix* );`  
+`$.fn.cacheImages.drop();	// Drop all images`  
+`$.fn.cacheImages.drop('http://upload.wikimedia.org/wikipedia/commons/1/1d/Fishfinger1.jpg');	//Drop a specific image` 
+`$.fn.cacheImages.drop(null, 'cachedImages');	//Drop a set of images` 
 
-Helpful to clean up stored images from the cache without dropping everything stored. You can optionally set a *storagePrefix* in the function to only drop specific types of images.  
+Helpful to clean up stored images from the cache without dropping everything stored. You can optionally set a *url*, and/or *storagePrefix* in the function to only drop specific image, or set of images.  
 
 
 # Credits and Thanks  

jquery.cacheImages.indexeddb.js

@@ -153,18 +153,21 @@ window.indexedDB = window.indexedDB || window.mozIndexedDB || window.webkitIndex
 	/*
 	 *	Will remove all of the cached images from their localStorage
 	 */
-	$.fn.cacheImages.drop = function( storagePrefix ){
+	$.fn.cacheImages.drop = function( url, storagePrefix ){
 		var dropKeys = [],	// Store the keys we need to drop here
 			debug = false;
 		if( typeof storagePrefix === 'undefined' ){ storagePrefix = $.fn.cacheImages.defaults.storagePrefix; }
+		if( typeof url === 'undefined' ){ url = null; }
 
 		var request = window.cacheImagesDb.transaction("offlineImages", "readonly").objectStore("offlineImages").openCursor();
 		request.onsuccess = function(e) {
 			var cursor = e.target.result;
 			if (cursor) {
 				// Called for each matching record.
 				if( cursor.value.key.substr( 0,storagePrefix.length + 1 ) === storagePrefix + ':' ){	// Does not match our prefix?
-					dropKeys.push(cursor.value.key ); // Droping the keys here re-indexes the localStorage so that the offset in our loop is wrong
+					if( url === null || cursor.value.key === storagePrefix + ':' + url ){ 
+						dropKeys.push(cursor.value.key ); // Droping the keys here re-indexes the localStorage so that the offset in our loop is wrong
+					}
 				}
 				cursor.continue();
 			}else{

jquery.cacheImages.indexeddb.min.js

@@ -297,21 +297,23 @@
 	/*
 	 *	Will remove all of the cached images from their localStorage
 	 */
-	$.fn.cacheImages.drop = function( storagePrefix ){
+	$.fn.cacheImages.drop = function( url, storagePrefix ){
 		var dropKeys = [],	// Store the keys we need to drop here
 			debug = false;
 		if( typeof storagePrefix === 'undefined' ){ storagePrefix = $.fn.cacheImages.defaults.storagePrefix; }
+		if( typeof url === 'undefined' ){ url = null; }
 
 		// Lets get our loop on
 		for (i = 0; i < window.localStorage.length; i++) {
 			if( window.localStorage.key(i).substr( 0,storagePrefix.length + 1 ) !== storagePrefix + ':' ){ continue; }	// Does not match our prefix?
+			if( url !== null && window.localStorage.key(i) !== storagePrefix + ':' + url ){ continue; }
 
 			dropKeys.push( window.localStorage.key(i) ); // Droping the keys here re-indexes the localStorage so that the offset in our loop is wrong
 		}
 
 		if( dropKeys.length ===  0 ){
 			if( debug ){ console.log( 'No Images to Drop' ); }
-			return true;
+			return;
 		}
 
 		// Drop the keys we found
@@ -321,6 +323,6 @@
 		}
 
 		if( debug ){ console.log( 'Dropped ' + dropKeys.length + ' images from storage' ); }	// Provide a bit of feedback for developers
-		return true;
+		return;
 	};
 })(jQuery);