erp5_officejs: serviceworker download only new changed files

bt5/erp5_officejs/PathTemplateItem/web_page_module/gadget_officejs_serviceworker_js.js

 /*jslint indent: 2*/
-/*global self, caches, importScripts, fetch, Promise, Request, Response, jIO, console*/
+/*global self, caches, importScripts, fetch, Promise, Request, Response, jIO, console, Headers*/
 var global = self,
   window = self;
 (function (self, caches, fetch) {
@@ -12,10 +12,14 @@ var global = self,
   importScripts('rsvp.js', 'jiodev.js');
 
   Response.prototype.metadata = function () {
+    var headers = {};
+    Array.from(this.headers.entries()).forEach(function (data) {
+      headers[data[0]] = data[1];
+    });
     return {
       //'ok': this.ok
       url: this.url,
-      headers: Array.from(this.headers.entries())
+      headers: headers
     };
   };
 
@@ -41,21 +45,60 @@ var global = self,
     // debugger;
     // Perform install step:  loading each required file into cache
     // create a new jio
-    var requests = self.CACHE_REQUIRED_FILES.map(function (file_name) {
-          return new Request(file_name);
-        });
+    // TODO:
+    //    delete from cache not existing in self.CACHE_REQUIRED_FILES files.
+    var result_fetch = Promise.resolve(), // queue for fetching files
+        result_jio_save = Promise.resolve(); // queue for save files
+                                             // in end service mark as installed
 
     event.waitUntil(
-      Promise.all(requests.map(function (request) {
-        return fetch(request).then(function (response) {
-          return response.metadata_w_blob();
+      new Promise(function (resolve, reject) {
+        self.CACHE_REQUIRED_FILES.map(function (url, i) {
+          var request = new Request(url),
+            requests_len = self.CACHE_REQUIRED_FILES.length - 1,
+            jio_key = request.url;
+          // files download one by one
+          result_fetch = result_fetch.then(function () {
+            return new Promise(function (resolve) {
+              self.jio_cache_storage.get(jio_key)
+              .push(function (metadata) {
+                resolve(metadata);
+              })
+              .push(undefined, resolve);
             });
-      }))
-      .then(function (responses) {
-        return Promise.all(
-          responses.map(function (response, i) {
-            return new Promise(function (resolve, reject) {
-              var jio_key = requests[i].url;
+          })
+          .then(function (metadata) {
+            if (metadata.url !== undefined) {
+              var modification_mark_exist = false;
+              if (metadata.headers.ETag !== undefined) {
+                modification_mark_exist = true;
+                request.headers.append('If-None-Match', metadata.headers.Etag);
+              } else if (metadata.headers['last-modified'] !== undefined) {
+                modification_mark_exist = true;
+                request.headers.append('If-Modified-Since', metadata.headers['last-modified']);
+              }
+              if (modification_mark_exist)
+                return fetch(request)
+                  .then(undefined, function () {
+                    // We say 'file not changed' if downloading is not possible with additional header
+                    return new Response(null, {status: 304});
+                  });
+            }
+            return fetch(request);
+          })
+          .then(function (response) {
+            if (response.status === 304) {
+              if (i === requests_len) {
+                // latest file saved
+                result_jio_save = result_jio_save.then(resolve);
+              }
+              return Promise.resolve();
+            } else {
+              return response.metadata_w_blob()
+                .then(function (response) {
+                  // files save one by one
+                  result_jio_save = result_jio_save.then(function () {
+                    return new Promise(function (resolve) {
                       self.jio_cache_storage.put(jio_key, response.metadata)
                       .push(function () {
                         return self.jio_cache_storage.putAttachment(
@@ -72,16 +115,23 @@ var global = self,
                         console.log(error);
                         reject();
                       });
+                    });
+                  });
+                  if (i === requests_len) {
+                    // latest file saved
+                    result_jio_save = result_jio_save.then(resolve);
+                  }
+                  return Promise.resolve();
+                });
+            }
+          });
+        });
       })
-            .then(undefined, console.log);
-          })
-        )
       .then(function () {
         console.log('cache loaded');
         return self.skipWaiting();
       })
-        .then(undefined, console.log);
-      })
+      .then(undefined, console.log)
     );
   };
 
@@ -92,7 +142,6 @@ var global = self,
         .push(function (metadata) {
           return self.jio_cache_storage.getAttachment(jio_key, 'body')
           .push(function (body) {
-            //console.log(metadata.url + ' return from jio');
             resolve(new Response(body, {'headers': metadata.headers}));
           });
         })

bt5/erp5_officejs/PathTemplateItem/web_page_module/gadget_officejs_serviceworker_js.xml

@@ -230,7 +230,7 @@
             </item>
             <item>
                 <key> <string>serial</string> </key>
-                <value> <string>951.9272.8708.15735</string> </value>
+                <value> <string>951.20619.45573.30156</string> </value>
             </item>
             <item>
                 <key> <string>state</string> </key>
@@ -248,7 +248,7 @@
                     </tuple>
                     <state>
                       <tuple>
-                        <float>1463082861.33</float>
+                        <float>1463735862.94</float>
                         <string>UTC</string>
                       </tuple>
                     </state>