ReplicateStorage: add automatic conflict resolution

Configure the storage with the conflict_handling parameter value:
   0: (default): no resolution (ie, throw an Error)
   1: keep the local state
      (overwrites the remote document with local content)
      (delete remote document if local is deleted)
   2: keep the remote state
      (overwrites the local document with remote content)
      (delete local document if remote is deleted)
   3: keep both copies (leave documents untouched, no signature update)

src/jio.storage/replicatestorage.js

@@ -22,7 +22,11 @@
 (function (jIO, RSVP, Rusha) {
   "use strict";
 
-  var rusha = new Rusha();
+  var rusha = new Rusha(),
+    CONFLICT_THROW = 0,
+    CONFLICT_KEEP_LOCAL = 1,
+    CONFLICT_KEEP_REMOTE = 2,
+    CONFLICT_CONTINUE = 3;
 
   /****************************************************
    Use a local jIO to read/write/search documents
@@ -53,6 +57,24 @@
     });
 
     this._use_remote_post = spec.use_remote_post || false;
+
+    this._conflict_handling = spec.conflict_handling || 0;
+    // 0: no resolution (ie, throw an Error)
+    // 1: keep the local state
+    //    (overwrites the remote document with local content)
+    //    (delete remote document if local is deleted)
+    // 2: keep the remote state
+    //    (overwrites the local document with remote content)
+    //    (delete local document if remote is deleted)
+    // 3: keep both copies (leave documents untouched, no signature update)
+    if ((this._conflict_handling !== CONFLICT_THROW) &&
+        (this._conflict_handling !== CONFLICT_KEEP_LOCAL) &&
+        (this._conflict_handling !== CONFLICT_KEEP_REMOTE) &&
+        (this._conflict_handling !== CONFLICT_CONTINUE)) {
+      throw new jIO.util.jIOError("Unsupported conflict handling: " +
+                                  this._conflict_handling, 400);
+    }
+
     this._check_local_modification = spec.check_local_modification;
     if (this._check_local_modification === undefined) {
       this._check_local_modification = true;
@@ -208,6 +230,13 @@
                 skip_document_dict[id] = null;
               });
           }
+          if (options.conflict_ignore === true) {
+            return;
+          }
+          if (options.conflict_force === true) {
+            return propagateModification(source, destination, doc, local_hash,
+                                         id, options);
+          }
           // Already exists on destination
           throw new jIO.util.jIOError("Conflict on '" + id + "'",
                                       409);
@@ -279,7 +308,8 @@
         });
     }
 
-    function checkSignatureDifference(queue, source, destination, id) {
+    function checkSignatureDifference(queue, source, destination, id,
+                                      conflict_force, conflict_ignore) {
       queue
         .push(function () {
           return RSVP.all([
@@ -308,8 +338,13 @@
                         skip_document_dict[id] = null;
                       });
                   }
-                  throw new jIO.util.jIOError("Conflict on '" + id + "'",
-                                              409);
+                  if (conflict_ignore === true) {
+                    return;
+                  }
+                  if (conflict_force !== true) {
+                    throw new jIO.util.jIOError("Conflict on '" + id + "'",
+                                                409);
+                  }
                 }
                 return propagateModification(source, destination, doc,
                                              local_hash, id);
@@ -384,7 +419,9 @@
             if (signature_dict.hasOwnProperty(key)) {
               if (local_dict.hasOwnProperty(key)) {
                 if (options.check_modification === true) {
-                  checkSignatureDifference(queue, source, destination, key);
+                  checkSignatureDifference(queue, source, destination, key,
+                                           options.conflict_force,
+                                           options.conflict_ignore);
                 }
               } else {
                 if (options.check_deletion === true) {
@@ -440,6 +477,12 @@
                              context._remote_sub_storage,
                              {
               use_post: context._use_remote_post,
+              conflict_force: (context._conflict_handling ===
+                               CONFLICT_KEEP_LOCAL),
+              conflict_ignore: ((context._conflict_handling ===
+                                 CONFLICT_CONTINUE) ||
+                                (context._conflict_handling ===
+                                 CONFLICT_KEEP_REMOTE)),
               check_modification: context._check_local_modification,
               check_creation: context._check_local_creation,
               check_deletion: context._check_local_deletion
@@ -464,6 +507,10 @@
           return pushStorage(context._remote_sub_storage,
                              context._local_sub_storage, {
               use_bulk_get: use_bulk_get,
+              conflict_force: (context._conflict_handling ===
+                               CONFLICT_KEEP_REMOTE),
+              conflict_ignore: (context._conflict_handling ===
+                                CONFLICT_CONTINUE),
               check_modification: context._check_remote_modification,
               check_creation: context._check_remote_creation,
               check_deletion: context._check_remote_deletion

test/jio.storage/replicatestorage.tests.js

@@ -46,6 +46,7 @@
 
     deepEqual(jio.__storage._query_options, {});
     equal(jio.__storage._use_remote_post, false);
+    equal(jio.__storage._conflict_handling, 0);
     equal(jio.__storage._check_local_creation, true);
     equal(jio.__storage._check_local_deletion, true);
     equal(jio.__storage._check_local_modification, true);
@@ -80,6 +81,7 @@
       },
       query: {query: 'portal_type: "Foo"', limit: [0, 1234567890]},
       use_remote_post: true,
+      conflict_handling: 3,
       check_local_creation: false,
       check_local_deletion: false,
       check_local_modification: false,
@@ -93,6 +95,7 @@
       {query: 'portal_type: "Foo"', limit: [0, 1234567890]}
     );
     equal(jio.__storage._use_remote_post, true);
+    equal(jio.__storage._conflict_handling, 3);
     equal(jio.__storage._check_local_creation, false);
     equal(jio.__storage._check_local_deletion, false);
     equal(jio.__storage._check_local_modification, false);
@@ -104,6 +107,31 @@
           "_replicate_623653d45a4e770a2c9f6b71e3144d18ee1b5bec");
   });
 
+  test("reject unknow conflict resolution", function () {
+    throws(
+      function () {
+        jIO.createJIO({
+          type: "replicate",
+          local_sub_storage: {
+            type: "replicatestorage200"
+          },
+          remote_sub_storage: {
+            type: "replicatestorage500"
+          },
+          query: {query: 'portal_type: "Foo"', limit: [0, 1234567890]},
+          conflict_handling: 4
+        });
+      },
+      function (error) {
+        ok(error instanceof jIO.util.jIOError);
+        equal(error.status_code, 400);
+        equal(error.message,
+              "Unsupported conflict handling: 4");
+        return true;
+      }
+    );
+  });
+
   /////////////////////////////////////////////////////////////////
   // replicateStorage.get
   /////////////////////////////////////////////////////////////////
@@ -847,6 +875,195 @@
       });
   });
 
+  test("local and remote document creations: keep local", function () {
+    stop();
+    expect(3);
+
+    var context = this;
+
+    this.jio = jIO.createJIO({
+      type: "replicate",
+      local_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      remote_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      conflict_handling: 1
+    });
+
+    RSVP.all([
+      context.jio.put("conflict", {"title": "foo"}),
+      context.jio.__storage._remote_sub_storage.put("conflict",
+                                                    {"title": "bar"})
+    ])
+      .then(function () {
+        return context.jio.repair();
+      })
+      .then(function () {
+        return context.jio.__storage._signature_sub_storage.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          hash: "5ea9013447539ad65de308cbd75b5826a2ae30e5"
+        });
+      })
+      .then(function () {
+        return context.jio.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo"
+        });
+      })
+      .then(function () {
+        return context.jio.__storage._remote_sub_storage.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo"
+        });
+      })
+      .fail(function (error) {
+        ok(false, error);
+      })
+      .always(function () {
+        start();
+      });
+  });
+
+  test("local and remote document creations: keep remote", function () {
+    stop();
+    expect(3);
+
+    var context = this;
+
+    this.jio = jIO.createJIO({
+      type: "replicate",
+      local_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      remote_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      conflict_handling: 2
+    });
+
+    RSVP.all([
+      context.jio.put("conflict", {"title": "foo"}),
+      context.jio.__storage._remote_sub_storage.put("conflict",
+                                                    {"title": "bar"})
+    ])
+      .then(function () {
+        return context.jio.repair();
+      })
+      .then(function () {
+        return context.jio.__storage._signature_sub_storage.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          hash: "6799f3ea80e325b89f19589282a343c376c1f1af"
+        });
+      })
+      .then(function () {
+        return context.jio.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "bar"
+        });
+      })
+      .then(function () {
+        return context.jio.__storage._remote_sub_storage.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "bar"
+        });
+      })
+      .fail(function (error) {
+        ok(false, error);
+      })
+      .always(function () {
+        start();
+      });
+  });
+
+  test("local and remote document creations: continue", function () {
+    stop();
+    expect(4);
+
+    var context = this;
+
+    this.jio = jIO.createJIO({
+      type: "replicate",
+      local_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      remote_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      conflict_handling: 3
+    });
+
+    RSVP.all([
+      context.jio.put("conflict", {"title": "foo"}),
+      context.jio.__storage._remote_sub_storage.put("conflict",
+                                                    {"title": "bar"})
+    ])
+      .then(function () {
+        return context.jio.repair();
+      })
+      .then(function () {
+        return context.jio.__storage._signature_sub_storage.get("conflict");
+      })
+      .fail(function (error) {
+        ok(error instanceof jIO.util.jIOError);
+//        equal(error.message, "Cannot find document: conflict");
+        equal(error.status_code, 404);
+      })
+      .then(function () {
+        return context.jio.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo"
+        });
+      })
+      .then(function () {
+        return context.jio.__storage._remote_sub_storage.get("conflict");
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "bar"
+        });
+      })
+      .fail(function (error) {
+        ok(false, error);
+      })
+      .always(function () {
+        start();
+      });
+  });
+
   test("local and remote same document creations", function () {
     stop();
     expect(1);
@@ -1182,6 +1399,216 @@
       });
   });
 
+  test("local and remote document modifications: keep local", function () {
+    stop();
+    expect(3);
+
+    var id,
+      context = this;
+
+    this.jio = jIO.createJIO({
+      type: "replicate",
+      local_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      remote_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      conflict_handling: 1
+    });
+
+    context.jio.post({"title": "foo"})
+      .then(function (result) {
+        id = result;
+        return context.jio.repair();
+      })
+      .then(function () {
+        return RSVP.all([
+          context.jio.put(id, {"title": "foo4"}),
+          context.jio.__storage._remote_sub_storage.put(id, {"title": "foo5"})
+        ]);
+      })
+      .then(function () {
+        return context.jio.repair();
+      })
+      .then(function () {
+        return context.jio.__storage._signature_sub_storage.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          hash: "6f700e813022233a785692585484c21cb5a412fd"
+        });
+      })
+      .then(function () {
+        return context.jio.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo4"
+        });
+      })
+      .then(function () {
+        return context.jio.__storage._remote_sub_storage.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo4"
+        });
+      })
+      .fail(function (error) {
+        ok(false, error);
+      })
+      .always(function () {
+        start();
+      });
+  });
+
+  test("local and remote document modifications: keep remote", function () {
+    stop();
+    expect(3);
+
+    var id,
+      context = this;
+
+    this.jio = jIO.createJIO({
+      type: "replicate",
+      local_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      remote_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      conflict_handling: 2
+    });
+
+    context.jio.post({"title": "foo"})
+      .then(function (result) {
+        id = result;
+        return context.jio.repair();
+      })
+      .then(function () {
+        return RSVP.all([
+          context.jio.put(id, {"title": "foo4"}),
+          context.jio.__storage._remote_sub_storage.put(id, {"title": "foo5"})
+        ]);
+      })
+      .then(function () {
+        return context.jio.repair();
+      })
+      .then(function () {
+        return context.jio.__storage._signature_sub_storage.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          hash: "7bea6f87fd1dda14e340e5b14836cc8578fd615f"
+        });
+      })
+      .then(function () {
+        return context.jio.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo5"
+        });
+      })
+      .then(function () {
+        return context.jio.__storage._remote_sub_storage.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo5"
+        });
+      })
+      .fail(function (error) {
+        ok(false, error);
+      })
+      .always(function () {
+        start();
+      });
+  });
+
+  test("local and remote document modifications: continue", function () {
+    stop();
+    expect(3);
+
+    var id,
+      context = this;
+
+    this.jio = jIO.createJIO({
+      type: "replicate",
+      local_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      remote_sub_storage: {
+        type: "uuid",
+        sub_storage: {
+          type: "memory"
+        }
+      },
+      conflict_handling: 3
+    });
+
+    context.jio.post({"title": "foo"})
+      .then(function (result) {
+        id = result;
+        return context.jio.repair();
+      })
+      .then(function () {
+        return RSVP.all([
+          context.jio.put(id, {"title": "foo4"}),
+          context.jio.__storage._remote_sub_storage.put(id, {"title": "foo5"})
+        ]);
+      })
+      .then(function () {
+        return context.jio.repair();
+      })
+      .then(function () {
+        return context.jio.__storage._signature_sub_storage.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          hash: "5ea9013447539ad65de308cbd75b5826a2ae30e5"
+        });
+      })
+      .then(function () {
+        return context.jio.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo4"
+        });
+      })
+      .then(function () {
+        return context.jio.__storage._remote_sub_storage.get(id);
+      })
+      .then(function (result) {
+        deepEqual(result, {
+          title: "foo5"
+        });
+      })
+      .fail(function (error) {
+        ok(false, error);
+      })
+      .always(function () {
+        start();
+      });
+  });
+
   test("local and remote document same modifications", function () {
     stop();
     expect(1);