indexeddbstorage: replace promise for transaction by callback

/reviewed-on nexedi/jio!57

src/jio.storage/indexeddbstorage.js

@@ -148,9 +148,7 @@
     return tx;
   }
 
-  function handleCursor(request, callback) {
-    function resolver(resolve, reject) {
-      // Open DB //
+  function handleCursor(request, callback, resolve, reject) {
     request.onerror = function (error) {
       if (request.transaction) {
         request.transaction.abort();
@@ -175,9 +173,6 @@
       }
     };
   }
-    // XXX Canceller???
-    return new RSVP.Promise(resolver);
-  }
 
   IndexedDBStorage.prototype.buildQuery = function (options) {
     var result_list = [];
@@ -198,40 +193,45 @@
     }
     return openIndexedDB(this)
       .push(function (db) {
+        return new RSVP.Promise(function (resolve, reject) {
           var tx = openTransaction(db, ["metadata"], "readonly");
           if (options.include_docs === true) {
-          return handleCursor(tx.objectStore("metadata").index("_id")
-                              .openCursor(), pushIncludedMetadata);
+            handleCursor(tx.objectStore("metadata").index("_id").openCursor(),
+              pushIncludedMetadata, resolve, reject);
+          } else {
+            handleCursor(tx.objectStore("metadata").index("_id")
+                            .openKeyCursor(), pushMetadata, resolve, reject);
           }
-        return handleCursor(tx.objectStore("metadata").index("_id")
-                            .openKeyCursor(), pushMetadata);
+        });
       })
       .push(function () {
         return result_list;
       });
-
   };
 
-  function handleGet(request) {
-    function resolver(resolve, reject) {
+  function handleGet(request, resolve, reject) {
     request.onerror = reject;
     request.onsuccess = function () {
       if (request.result) {
         resolve(request.result);
-        }
+      } else {
         // XXX How to get ID
         reject(new jIO.util.jIOError("Cannot find document", 404));
-      };
       }
-    return new RSVP.Promise(resolver);
+    };
   }
 
   IndexedDBStorage.prototype.get = function (id) {
     return openIndexedDB(this)
       .push(function (db) {
-        var transaction = openTransaction(db, ["metadata"],
-                                          "readonly");
-        return handleGet(transaction.objectStore("metadata").get(id));
+        return new RSVP.Promise(function (resolve, reject) {
+          var transaction = openTransaction(db, ["metadata"], "readonly");
+          handleGet(
+            transaction.objectStore("metadata").get(id),
+            resolve,
+            reject
+          );
+        });
       })
       .push(function (result) {
         return result.doc;
@@ -247,37 +247,51 @@
 
     return openIndexedDB(this)
       .push(function (db) {
+        return new RSVP.Promise(function (resolve, reject) {
           var transaction = openTransaction(db, ["metadata", "attachment"],
             "readonly");
-        return RSVP.all([
-          handleGet(transaction.objectStore("metadata").get(id)),
-          handleCursor(transaction.objectStore("attachment").index("_id")
-                       .openCursor(IDBKeyRange.only(id)), addEntry)
-        ]);
+          function getAttachments() {
+            handleCursor(
+              transaction.objectStore("attachment").index("_id")
+                .openCursor(IDBKeyRange.only(id)),
+              addEntry,
+              resolve,
+              reject
+            );
+          }
+          handleGet(
+            transaction.objectStore("metadata").get(id),
+            getAttachments,
+            reject
+          );
+        });
       })
       .push(function () {
         return attachment_dict;
       });
   };
 
-  function handleRequest(request) {
-    function resolver(resolve, reject) {
+  function handleRequest(request, resolve, reject) {
     request.onerror = reject;
     request.onsuccess = function () {
       resolve(request.result);
     };
   }
-    return new RSVP.Promise(resolver);
-  }
 
   IndexedDBStorage.prototype.put = function (id, metadata) {
     return openIndexedDB(this)
       .push(function (db) {
+        return new RSVP.Promise(function (resolve, reject) {
           var transaction = openTransaction(db, ["metadata"], "readwrite");
-        return handleRequest(transaction.objectStore("metadata").put({
+          handleRequest(
+            transaction.objectStore("metadata").put({
               "_id": id,
               "doc": metadata
-        }));
+            }),
+            resolve,
+            reject
+          );
+        });
       });
   };
 
@@ -286,19 +300,38 @@
   }
 
   IndexedDBStorage.prototype.remove = function (id) {
+    var resolved_amount = 0;
     return openIndexedDB(this)
       .push(function (db) {
+        return new RSVP.Promise(function (resolve, reject) {
+          function resolver() {
+            if (resolved_amount < 2) {
+              resolved_amount += 1;
+            } else {
+              resolve();
+            }
+          }
           var transaction = openTransaction(db, ["metadata", "attachment",
                                             "blob"], "readwrite");
-        return RSVP.all([
-          handleRequest(transaction
-                        .objectStore("metadata")["delete"](id)),
+          handleRequest(
+            transaction.objectStore("metadata")["delete"](id),
+            resolver,
+            reject
+          );
           // XXX Why not possible to delete with KeyCursor?
           handleCursor(transaction.objectStore("attachment").index("_id")
-                       .openCursor(IDBKeyRange.only(id)), deleteEntry),
+              .openCursor(IDBKeyRange.only(id)),
+            deleteEntry,
+            resolver,
+            reject
+            );
           handleCursor(transaction.objectStore("blob").index("_id")
-                       .openCursor(IDBKeyRange.only(id)), deleteEntry)
-        ]);
+              .openCursor(IDBKeyRange.only(id)),
+            deleteEntry,
+            resolver,
+            reject
+            );
+        });
       });
   };
 
@@ -312,48 +345,64 @@
     }
     return openIndexedDB(this)
       .push(function (db) {
-        transaction = openTransaction(db, ["attachment", "blob"], "readonly");
-        // XXX Should raise if key is not good
-        return handleGet(transaction.objectStore("attachment")
-                         .get(buildKeyPath([id, name])));
-      })
-      .push(function (attachment) {
+        return new RSVP.Promise(function (resolve, reject) {
+          transaction = openTransaction(
+            db,
+            ["attachment", "blob"],
+            "readonly"
+          );
+          function getBlob(attachment) {
             var total_length = attachment.info.length,
-          i,
-          promise_list = [],
+              result_list = [],
               store = transaction.objectStore("blob"),
               start_index,
               end_index;
-
             type = attachment.info.content_type;
             start = options.start || 0;
             end = options.end || total_length;
             if (end > total_length) {
               end = total_length;
             }
-
             if (start < 0 || end < 0) {
-          throw new jIO.util.jIOError("_start and _end must be positive",
-                                      400);
+              throw new jIO.util.jIOError(
+                "_start and _end must be positive",
+                400
+              );
             }
             if (start > end) {
               throw new jIO.util.jIOError("_start is greater than _end",
                                           400);
             }
-
             start_index = Math.floor(start / UNITE);
-        end_index =  Math.floor(end / UNITE);
+            end_index =  Math.floor(end / UNITE) - 1;
             if (end % UNITE === 0) {
               end_index -= 1;
             }
-
-        for (i = start_index; i <= end_index; i += 1) {
-          promise_list.push(
-            handleGet(store.get(buildKeyPath([id,
-                                name, i])))
+            function resolver(result) {
+              result_list.push(result);
+              resolve(result_list);
+            }
+            function getPart(i) {
+              return function (result) {
+                if (result) {
+                  result_list.push(result);
+                }
+                i += 1;
+                handleGet(store.get(buildKeyPath([id, name, i])),
+                  (i <= end_index) ? getPart(i) : resolver,
+                  reject
                   );
+              };
             }
-        return RSVP.all(promise_list);
+            getPart(start_index - 1)();
+          }
+        // XXX Should raise if key is not good
+          handleGet(transaction.objectStore("attachment")
+                         .get(buildKeyPath([id, name])),
+            getBlob,
+            reject
+            );
+        });
       })
       .push(function (result_list) {
         var array_buffer_list = [],
@@ -374,19 +423,24 @@
       });
   };
 
-  function removeAttachment(transaction, id, name) {
-    return RSVP.all([
+  function removeAttachment(transaction, id, name, resolve, reject) {
       // XXX How to get the right attachment
-      handleRequest(transaction.objectStore("attachment")["delete"](
+    function deleteContent() {
+      handleCursor(
+        transaction.objectStore("blob").index("_id_attachment")
+          .openCursor(IDBKeyRange.only([id, name])),
+        deleteEntry,
+        resolve,
+        reject
+      );
+    }
+    handleRequest(
+      transaction.objectStore("attachment")["delete"](
         buildKeyPath([id, name])
-      )),
-      handleCursor(transaction.objectStore("blob").index("_id_attachment")
-                   .openCursor(IDBKeyRange.only(
-          [id, name]
-        )),
-          deleteEntry
-        )
-    ]);
+      ),
+      deleteContent,
+      reject
+    );
   }
 
   IndexedDBStorage.prototype.putAttachment = function (id, name, blob) {
@@ -414,12 +468,29 @@
 
         // Remove previous attachment
         transaction = openTransaction(db, ["attachment", "blob"], "readwrite");
-        return removeAttachment(transaction, id, name);
-      })
-      .push(function () {
-
-        var promise_list = [
-            handleRequest(transaction.objectStore("attachment").put({
+        return new RSVP.Promise(function (resolve, reject) {
+          function write() {
+            var len = blob_part.length - 1,
+              attachment_store = transaction.objectStore("attachment"),
+              blob_store = transaction.objectStore("blob");
+            function putBlobPart(i) {
+              return function () {
+                i += 1;
+                handleRequest(
+                  blob_store.put({
+                    "_key_path": buildKeyPath([id, name, i]),
+                    "_id" : id,
+                    "_attachment" : name,
+                    "_part" : i,
+                    "blob": blob_part[i]
+                  }),
+                  (i < len) ? putBlobPart(i) : resolve,
+                  reject
+                );
+              };
+            }
+            handleRequest(
+              attachment_store.put({
                 "_key_path": buildKeyPath([id, name]),
                 "_id": id,
                 "_attachment": name,
@@ -427,25 +498,13 @@
                   "content_type": blob.type,
                   "length": blob.size
                 }
-            }))
-          ],
-          len = blob_part.length,
-          blob_store = transaction.objectStore("blob"),
-          i;
-        for (i = 0; i < len; i += 1) {
-          promise_list.push(
-            handleRequest(blob_store.put({
-              "_key_path": buildKeyPath([id, name,
-                                         i]),
-              "_id" : id,
-              "_attachment" : name,
-              "_part" : i,
-              "blob": blob_part[i]
-            }))
+              }),
+              putBlobPart(-1),
+              reject
             );
           }
-        // Store all new data
-        return RSVP.all(promise_list);
+          removeAttachment(transaction, id, name, write, reject);
+        });
       });
   };
 
@@ -454,7 +513,9 @@
       .push(function (db) {
         var transaction = openTransaction(db, ["attachment", "blob"],
                                           "readwrite");
-        return removeAttachment(transaction, id, name);
+        return new RSVP.Promise(function (resolve, reject) {
+          removeAttachment(transaction, id, name, resolve, reject);
+        });
       });
   };