Add ZipStorage.

This storage will transparently compress getAttachment/putAttachment results.
Only text, json, xml mme type are compressed.

Thanks to Lucas Parsy.

Gruntfile.js

@@ -146,6 +146,7 @@ module.exports = function (grunt) {
         src: [
           'lib/uri/URI.js',
           'node_modules/uritemplate/bin/uritemplate.js',
+          'node_modules/lz-string/libs/lz-string.js',
 //           'node_modules/moment/moment.js',
           'lib/moment/moment-2.5.0.js',
 //           'src/*.js',
@@ -178,6 +179,7 @@ module.exports = function (grunt) {
           'src/jio.storage/uuidstorage.js',
           'src/jio.storage/memorystorage.js',
           'src/jio.storage/localstorage.js',
+          'src/jio.storage/zipstorage.js',
           'src/jio.storage/davstorage.js',
           'src/jio.storage/unionstorage.js',
           'src/jio.storage/erp5storage.js',

Makefile

@@ -43,6 +43,7 @@ zip:
 	@cp src/jio.storage/splitstorage.js     $(TMPDIR)/jio/storage/
 	@cp src/jio.storage/cryptstorage.js     $(TMPDIR)/jio/storage/
 	@cp src/jio.storage/revisionstorage.js  $(TMPDIR)/jio/storage/
+	@cp src/jio.storage/zipstorage.js       $(TMPDIR)/jio/storage/
 	@cp src/jio.storage/replicaterevisionstorage.js     $(TMPDIR)/jio/storage/
 	@cp src/jio.storage/s3storage.js        $(TMPDIR)/jio/storage/
 	@cp src/jio.storage/splitstorage.js     $(TMPDIR)/jio/storage/
@@ -75,6 +76,7 @@ zip:
 	@$(UGLIFY) src/jio.storage/cryptstorage.js     >$(TMPDIR)/jio/storage/cryptstorage.min.js 2>/dev/null
 	@$(UGLIFY) src/jio.storage/revisionstorage.js     >$(TMPDIR)/jio/storage/revisionstorage.min.js 2>/dev/null
 	@$(UGLIFY) src/jio.storage/replicaterevisionstorage.js     >$(TMPDIR)/jio/storage/replicaterevisionstorage.min.js 2>/dev/null
+	@$(UGLIFY) src/jio.storage/zipstorage.js						 >$(TMPDIR)/jio/storage/zipstorage.min.js 2>/dev/null
 	@$(UGLIFY) src/jio.storage/s3storage.js        >$(TMPDIR)/jio/storage/s3storage.min.js 2>/dev/null
 	@$(UGLIFY) src/jio.storage/splitstorage.js     >$(TMPDIR)/jio/storage/splitstorage.min.js 2>/dev/null
 	@$(UGLIFY) src/jio.storage/xwikistorage.js     >$(TMPDIR)/jio/storage/xwikistorage.min.js 2>/dev/null

examples/scenario.js

@@ -25,7 +25,10 @@
 //             type: "document",
 //             document_id: "/",
 //             sub_storage: {
-//               type: "local"
+//               type: "zip",
+//               sub_storage: {
+//                 type: "local"
+//               }
 //             }
 //           }
 //         }

package.json

@@ -45,6 +45,7 @@
     "grunt-contrib-qunit": "~0.3.0",
     "grunt-contrib-watch": "~0.5.3",
     "grunt-jslint": "~1.0.0",
+    "lz-string": "^1.4.4",
     "sinon": "~1.7.3",
     "connect-livereload": "~0.3.0",
     "grunt-open": "~0.2.2",

src/jio.js

-/*global window, RSVP, Blob, XMLHttpRequest, QueryFactory, Query, FileReader */
-(function (window, RSVP, Blob, QueryFactory, Query,
-           FileReader) {
+/*global window, RSVP, Blob, XMLHttpRequest, QueryFactory, Query, atob,
+  FileReader, ArrayBuffer, Uint8Array */
+(function (window, RSVP, Blob, QueryFactory, Query, atob,
+           FileReader, ArrayBuffer, Uint8Array) {
   "use strict";
 
   var util = {},
@@ -173,6 +174,25 @@
   }
   util.readBlobAsDataURL = readBlobAsDataURL;
 
+  // https://gist.github.com/davoclavo/4424731
+  function dataURItoBlob(dataURI) {
+    // convert base64 to raw binary data held in a string
+    var byteString = atob(dataURI.split(',')[1]),
+    // separate out the mime component
+      mimeString = dataURI.split(',')[0].split(':')[1],
+    // write the bytes of the string to an ArrayBuffer
+      arrayBuffer = new ArrayBuffer(byteString.length),
+      _ia = new Uint8Array(arrayBuffer),
+      i;
+    mimeString = mimeString.slice(0, mimeString.length - ";base64".length);
+    for (i = 0; i < byteString.length; i += 1) {
+      _ia[i] = byteString.charCodeAt(i);
+    }
+    return new Blob([arrayBuffer], {type: mimeString});
+  }
+
+  util.dataURItoBlob = dataURItoBlob;
+
   // tools
   function checkId(argument_list, storage, method_name) {
     if (typeof argument_list[0] !== 'string' || argument_list[0] === '') {
@@ -515,4 +535,5 @@
   jIO = new JioBuilder();
   window.jIO = jIO;
 
-}(window, RSVP, Blob, QueryFactory, Query, FileReader));
+}(window, RSVP, Blob, QueryFactory, Query, atob,
+  FileReader, ArrayBuffer, Uint8Array));

src/jio.storage/localstorage.js

@@ -5,8 +5,7 @@
  */
 
 /*jslint nomen: true*/
-/*global jIO, sessionStorage, localStorage, Blob, RSVP, atob,
-         ArrayBuffer, Uint8Array*/
+/*global jIO, sessionStorage, localStorage, RSVP */
 
 /**
  * JIO Local Storage. Type = 'local'.
@@ -22,8 +21,7 @@
  * @class LocalStorage
  */
 
-(function (jIO, sessionStorage, localStorage, Blob, RSVP,
-           atob, ArrayBuffer, Uint8Array) {
+(function (jIO, sessionStorage, localStorage, RSVP) {
   "use strict";
 
   function LocalStorage(spec) {
@@ -60,23 +58,6 @@
     return attachments;
   };
 
-  // https://gist.github.com/davoclavo/4424731
-  function dataURItoBlob(dataURI) {
-    // convert base64 to raw binary data held in a string
-    var byteString = atob(dataURI.split(',')[1]),
-      // separate out the mime component
-      mimeString = dataURI.split(',')[0].split(':')[1],
-      // write the bytes of the string to an ArrayBuffer
-      arrayBuffer = new ArrayBuffer(byteString.length),
-      _ia = new Uint8Array(arrayBuffer),
-      i;
-    mimeString = mimeString.slice(0, mimeString.length - ";base64".length);
-    for (i = 0; i < byteString.length; i += 1) {
-      _ia[i] = byteString.charCodeAt(i);
-    }
-    return new Blob([arrayBuffer], {type: mimeString});
-  }
-
   LocalStorage.prototype.getAttachment = function (id, name) {
     restrictDocumentId(id);
 
@@ -88,7 +69,7 @@
         404
       );
     }
-    return dataURItoBlob(textstring);
+    return jIO.util.dataURItoBlob(textstring);
   };
 
   LocalStorage.prototype.putAttachment = function (id, name, blob) {
@@ -125,5 +106,4 @@
 
   jIO.addStorage('local', LocalStorage);
 
-}(jIO, sessionStorage, localStorage, Blob, RSVP,
-  atob, ArrayBuffer, Uint8Array));
+}(jIO, sessionStorage, localStorage, RSVP));

src/jio.storage/zipstorage.js

+/*jslint nomen: true*/
+/*global RSVP, Blob, LZString, DOMException*/
+(function (RSVP, Blob, LZString, DOMException) {
+  "use strict";
+
+  /**
+   * The jIO ZipStorage extension
+   *
+   * @class ZipStorage
+   * @constructor
+   */
+
+  var MIME_TYPE = "application/x-jio-utf16_lz_string";
+
+  function ZipStorage(spec) {
+    this._sub_storage = jIO.createJIO(spec.sub_storage);
+  }
+
+  ZipStorage.prototype.get = function () {
+    return this._sub_storage.get.apply(this._sub_storage,
+                                        arguments);
+  };
+
+  ZipStorage.prototype.post = function () {
+    return this._sub_storage.post.apply(this._sub_storage,
+                                        arguments);
+  };
+
+  ZipStorage.prototype.put = function () {
+    return this._sub_storage.put.apply(this._sub_storage,
+                                       arguments);
+  };
+
+  ZipStorage.prototype.remove = function () {
+    return this._sub_storage.remove.apply(this._sub_storage,
+                                          arguments);
+  };
+
+  ZipStorage.prototype.hasCapacity = function () {
+    return this._sub_storage.hasCapacity.apply(this._sub_storage,
+                                               arguments);
+  };
+
+  ZipStorage.prototype.buildQuery = function () {
+    return this._sub_storage.buildQuery.apply(this._sub_storage,
+                                              arguments);
+  };
+
+  ZipStorage.prototype.getAttachment = function (id, name) {
+    var that = this;
+    return that._sub_storage.getAttachment(id, name)
+      .push(function (blob) {
+        if (blob.type !== MIME_TYPE) {
+          return blob;
+        }
+        return new RSVP.Queue()
+          .push(function () {
+            return jIO.util.readBlobAsText(blob, 'utf16');
+          })
+          .push(function (evt) {
+            var result =
+              LZString.decompressFromUTF16(evt.target.result);
+            if (result === '') {
+              return blob;
+            }
+            try {
+              return jIO.util.dataURItoBlob(
+                result
+              );
+            } catch (error) {
+              if (error instanceof DOMException) {
+                return blob;
+              }
+              throw error;
+            }
+          });
+      });
+  };
+
+  function myEndsWith(str, query) {
+    return (str.indexOf(query) === str.length - query.length);
+  }
+
+  ZipStorage.prototype.putAttachment = function (id, name, blob) {
+    var that = this;
+    if ((blob.type.indexOf("text/") === 0) || myEndsWith(blob.type, "xml") ||
+        myEndsWith(blob.type, "json")) {
+      return new RSVP.Queue()
+        .push(function () {
+          return jIO.util.readBlobAsDataURL(blob);
+        })
+        .push(function (data) {
+          var result = LZString.compressToUTF16(data.target.result);
+          blob = new Blob([result],
+                          {type: MIME_TYPE});
+          return that._sub_storage.putAttachment(id, name, blob);
+        });
+    }
+    return this._sub_storage.putAttachment.apply(this._sub_storage,
+                                                 arguments);
+  };
+
+  ZipStorage.prototype.removeAttachment = function () {
+    return this._sub_storage.removeAttachment.apply(this._sub_storage,
+                                                    arguments);
+  };
+
+  ZipStorage.prototype.allAttachments = function () {
+    return this._sub_storage.allAttachments.apply(this._sub_storage,
+                                                  arguments);
+  };
+
+  jIO.addStorage('zip', ZipStorage);
+}(RSVP, Blob, LZString, DOMException));

test/tests.html

@@ -43,6 +43,7 @@
 
   <!--script src="jio.storage/indexstorage.tests.js"></script-->
   <!--script src="jio.storage/dropboxstorage.tests.js"></script-->
+  <script src="jio.storage/zipstorage.tests.js"></script>
 
   <!--script src="../lib/jquery/jquery.min.js"></script>
   <script src="../src/jio.storage/xwikistorage.js"></script>