sharedb/test/milestone-db.js

JSON OT database backend

var expect = require('chai').expect;
var Backend = require('../lib/backend');
var MilestoneDB = require('../lib/milestone-db');
var NoOpMilestoneDB = require('../lib/milestone-db/no-op');
var Snapshot = require('../lib/snapshot');
var util = require('./util');

describe('Base class', function() {
  var db;

  beforeEach(function() {
    db = new MilestoneDB();
  });

  it('calls back with an error when trying to get a snapshot', function(done) {
    db.getMilestoneSnapshot('books', '123', 1, function(error) {
      expect(error.code).to.equal('ERR_DATABASE_METHOD_NOT_IMPLEMENTED');
      done();
    });
  });

  it('emits an error when trying to get a snapshot', function(done) {
    db.on('error', function(error) {
      expect(error.code).to.equal('ERR_DATABASE_METHOD_NOT_IMPLEMENTED');
      done();
    });

    db.getMilestoneSnapshot('books', '123', 1);
  });

  it('calls back with an error when trying to save a snapshot', function(done) {
    db.saveMilestoneSnapshot('books', {}, function(error) {
      expect(error.code).to.equal('ERR_DATABASE_METHOD_NOT_IMPLEMENTED');
      done();
    });
  });

  it('emits an error when trying to save a snapshot', function(done) {
    db.on('error', function(error) {
      expect(error.code).to.equal('ERR_DATABASE_METHOD_NOT_IMPLEMENTED');
      done();
    });

    db.saveMilestoneSnapshot('books', {});
  });

  it('calls back with an error when trying to get a snapshot before a time', function(done) {
    db.getMilestoneSnapshotAtOrBeforeTime('books', '123', 1000, function(error) {
      expect(error.code).to.equal('ERR_DATABASE_METHOD_NOT_IMPLEMENTED');
      done();
    });
  });

  it('calls back with an error when trying to get a snapshot after a time', function(done) {
    db.getMilestoneSnapshotAtOrAfterTime('books', '123', 1000, function(error) {
      expect(error.code).to.equal('ERR_DATABASE_METHOD_NOT_IMPLEMENTED');
      done();
    });
  });
});

describe('NoOpMilestoneDB', function() {
  var db;

  beforeEach(function() {
    db = new NoOpMilestoneDB();
  });

  it('does not error when trying to save and fetch a snapshot', function(done) {
    var snapshot = new Snapshot(
      'catcher-in-the-rye',
      2,
      'http://sharejs.org/types/JSONv0',
      {title: 'Catcher in the Rye'},
      null
    );

    util.callInSeries([
      function(next) {
        db.saveMilestoneSnapshot('books', snapshot, next);
      },
      function(next) {
        db.getMilestoneSnapshot('books', 'catcher-in-the-rye', null, next);
      },
      function(snapshot, next) {
        expect(snapshot).to.equal(undefined);
        next();
      },
      done
    ]);
  });

  it('emits an event when saving without a callback', function(done) {
    db.on('save', function() {
      done();
    });

    db.saveMilestoneSnapshot('books', undefined);
  });
});

module.exports = function(options) {
  var create = options.create;

  describe('Milestone Database', function() {
    var db;
    var backend;

    beforeEach(function(done) {
      create(function(error, createdDb) {
        if (error) return done(error);
        db = createdDb;
        backend = new Backend({milestoneDb: db});
        done();
      });
    });

    afterEach(function(done) {
      db.close(done);
    });

    it('can call close() without a callback', function(done) {
      create(function(error, db) {
        if (error) return done(error);
        db.close();
        done();
      });
    });

    it('stores and fetches a milestone snapshot', function(done) {
      var snapshot = new Snapshot(
        'catcher-in-the-rye',
        2,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye'},
        null
      );

      util.callInSeries([
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot, next);
        },
        function(next) {
          db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 2, next);
        },
        function(retrievedSnapshot, next) {
          expect(retrievedSnapshot).to.eql(snapshot);
          next();
        },
        done
      ]);
    });

    it('fetches the most recent snapshot before the requested version', function(done) {
      var snapshot1 = new Snapshot(
        'catcher-in-the-rye',
        1,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye'},
        null
      );

      var snapshot2 = new Snapshot(
        'catcher-in-the-rye',
        2,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye', author: 'J.D. Salinger'},
        null
      );

      var snapshot10 = new Snapshot(
        'catcher-in-the-rye',
        10,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye', author: 'J.D. Salinger', publicationDate: '1951-07-16'},
        null
      );

      util.callInSeries([
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot1, next);
        },
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot2, next);
        },
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot10, next);
        },
        function(next) {
          db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 4, next);
        },
        function(snapshot, next) {
          expect(snapshot).to.eql(snapshot2);
          next();
        },
        done
      ]);
    });

    it('fetches the most recent snapshot even if they are inserted in the wrong order', function(done) {
      var snapshot1 = new Snapshot(
        'catcher-in-the-rye',
        1,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye'},
        null
      );

      var snapshot2 = new Snapshot(
        'catcher-in-the-rye',
        2,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye', author: 'J.D. Salinger'},
        null
      );

      util.callInSeries([
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot2, next);
        },
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot1, next);
        },
        function(next) {
          db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 4, next);
        },
        function(snapshot, next) {
          expect(snapshot).to.eql(snapshot2);
          next();
        },
        done
      ]);
    });

    it('fetches the most recent snapshot when the version is null', function(done) {
      var snapshot1 = new Snapshot(
        'catcher-in-the-rye',
        1,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye'},
        null
      );

      var snapshot2 = new Snapshot(
        'catcher-in-the-rye',
        2,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye', author: 'J.D. Salinger'},
        null
      );

      util.callInSeries([
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot1, next);
        },
        function(next) {
          db.saveMilestoneSnapshot('books', snapshot2, next);
        },
        function(next) {
          db.getMilestoneSnapshot('books', 'catcher-in-the-rye', null, next);
        },
        function(snapshot, next) {
          expect(snapshot).to.eql(snapshot2);
          next();
        },
        done
      ]);
    });

    it('errors when fetching an undefined version', function(done) {
      db.getMilestoneSnapshot('books', 'catcher-in-the-rye', undefined, function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    it('errors when fetching version -1', function(done) {
      db.getMilestoneSnapshot('books', 'catcher-in-the-rye', -1, function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    it('errors when fetching version "foo"', function(done) {
      db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 'foo', function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    it('errors when fetching a null collection', function(done) {
      db.getMilestoneSnapshot(null, 'catcher-in-the-rye', 1, function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    it('errors when fetching a null ID', function(done) {
      db.getMilestoneSnapshot('books', null, 1, function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    it('errors when saving a null collection', function(done) {
      var snapshot = new Snapshot(
        'catcher-in-the-rye',
        1,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye'},
        null
      );

      db.saveMilestoneSnapshot(null, snapshot, function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    it('returns undefined if no snapshot exists', function(done) {
      util.callInSeries([
        function(next) {
          db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 1, next);
        },
        function(snapshot, next) {
          expect(snapshot).to.equal(undefined);
          next();
        },
        done
      ]);
    });

    it('does not store a milestone snapshot on commit', function(done) {
      util.callInSeries([
        function(next) {
          var doc = backend.connect().get('books', 'catcher-in-the-rye');
          doc.create({title: 'Catcher in the Rye'}, next);
        },
        function(next) {
          db.getMilestoneSnapshot('books', 'catcher-in-the-rye', null, next);
        },
        function(snapshot, next) {
          expect(snapshot).to.equal(undefined);
          next();
        },
        done
      ]);
    });

    it('can save without a callback', function(done) {
      var snapshot = new Snapshot(
        'catcher-in-the-rye',
        1,
        'http://sharejs.org/types/JSONv0',
        {title: 'Catcher in the Rye'},
        null
      );

      db.on('save', function(collection, snapshot) {
        expect(collection).to.equal('books');
        expect(snapshot).to.eql(snapshot);
        done();
      });

      db.saveMilestoneSnapshot('books', snapshot);
    });

    it('errors when the snapshot is undefined', function(done) {
      db.saveMilestoneSnapshot('books', undefined, function(error) {
        expect(error).instanceOf(Error);
        done();
      });
    });

    describe('snapshots with timestamps', function() {
      var snapshot1 = new Snapshot(
        'catcher-in-the-rye',
        1,
        'http://sharejs.org/types/JSONv0',
        {
          title: 'Catcher in the Rye'
        },
        {
          ctime: 1000,
          mtime: 1000
        }
      );

      var snapshot2 = new Snapshot(
        'catcher-in-the-rye',
        2,
        'http://sharejs.org/types/JSONv0',
        {
          title: 'Catcher in the Rye',
          author: 'JD Salinger'
        },
        {
          ctime: 1000,
          mtime: 2000
        }
      );

      var snapshot3 = new Snapshot(
        'catcher-in-the-rye',
        3,
        'http://sharejs.org/types/JSONv0',
        {
          title: 'Catcher in the Rye',
          author: 'J.D. Salinger'
        },
        {
          ctime: 1000,
          mtime: 3000
        }
      );

      beforeEach(function(done) {
        util.callInSeries([
          function(next) {
            db.saveMilestoneSnapshot('books', snapshot1, next);
          },
          function(next) {
            db.saveMilestoneSnapshot('books', snapshot2, next);
          },
          function(next) {
            db.saveMilestoneSnapshot('books', snapshot3, next);
          },
          done
        ]);
      });

      describe('fetching a snapshot before or at a time', function() {
        it('fetches a snapshot before a given time', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrBeforeTime('books', 'catcher-in-the-rye', 2500, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.eql(snapshot2);
              next();
            },
            done
          ]);
        });

        it('fetches a snapshot at an exact time', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrBeforeTime('books', 'catcher-in-the-rye', 2000, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.eql(snapshot2);
              next();
            },
            done
          ]);
        });

        it('fetches the first snapshot for a null timestamp', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrBeforeTime('books', 'catcher-in-the-rye', null, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.eql(snapshot1);
              next();
            },
            done
          ]);
        });

        it('returns an error for a string timestamp', function(done) {
          db.getMilestoneSnapshotAtOrBeforeTime('books', 'catcher-in-the-rye', 'not-a-timestamp', function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });

        it('returns an error for a negative timestamp', function(done) {
          db.getMilestoneSnapshotAtOrBeforeTime('books', 'catcher-in-the-rye', -1, function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });

        it('returns undefined if there are no snapshots before a time', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrBeforeTime('books', 'catcher-in-the-rye', 0, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.equal(undefined);
              next();
            },
            done
          ]);
        });

        it('errors if no collection is provided', function(done) {
          db.getMilestoneSnapshotAtOrBeforeTime(undefined, 'catcher-in-the-rye', 0, function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });

        it('errors if no ID is provided', function(done) {
          db.getMilestoneSnapshotAtOrBeforeTime('books', undefined, 0, function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });
      });

      describe('fetching a snapshot after or at a time', function() {
        it('fetches a snapshot after a given time', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrAfterTime('books', 'catcher-in-the-rye', 2500, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.eql(snapshot3);
              next();
            },
            done
          ]);
        });

        it('fetches a snapshot at an exact time', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrAfterTime('books', 'catcher-in-the-rye', 2000, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.eql(snapshot2);
              next();
            },
            done
          ]);
        });

        it('fetches the last snapshot for a null timestamp', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrAfterTime('books', 'catcher-in-the-rye', null, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.eql(snapshot3);
              next();
            },
            done
          ]);
        });

        it('returns an error for a string timestamp', function(done) {
          db.getMilestoneSnapshotAtOrAfterTime('books', 'catcher-in-the-rye', 'not-a-timestamp', function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });

        it('returns an error for a negative timestamp', function(done) {
          db.getMilestoneSnapshotAtOrAfterTime('books', 'catcher-in-the-rye', -1, function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });

        it('returns undefined if there are no snapshots after a time', function(done) {
          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshotAtOrAfterTime('books', 'catcher-in-the-rye', 4000, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.equal(undefined);
              next();
            },
            done
          ]);
        });

        it('errors if no collection is provided', function(done) {
          db.getMilestoneSnapshotAtOrAfterTime(undefined, 'catcher-in-the-rye', 0, function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });

        it('errors if no ID is provided', function(done) {
          db.getMilestoneSnapshotAtOrAfterTime('books', undefined, 0, function(error) {
            expect(error).instanceOf(Error);
            done();
          });
        });
      });
    });

    describe('milestones enabled for every version', function() {
      beforeEach(function(done) {
        var options = {interval: 1};

        create(options, function(error, createdDb) {
          if (error) return done(error);
          db = createdDb;
          backend = new Backend({milestoneDb: db});
          done();
        });
      });

      it('stores a milestone snapshot on commit', function(done) {
        db.on('save', function(collection, snapshot) {
          expect(collection).to.equal('books');
          expect(snapshot.data).to.eql({title: 'Catcher in the Rye'});
          done();
        });

        var doc = backend.connect().get('books', 'catcher-in-the-rye');
        doc.create({title: 'Catcher in the Rye'});
      });
    });

    describe('milestones enabled for every other version', function() {
      beforeEach(function(done) {
        var options = {interval: 2};

        create(options, function(error, createdDb) {
          if (error) return done(error);
          db = createdDb;
          backend = new Backend({milestoneDb: db});
          done();
        });
      });

      it('only stores even-numbered versions', function(done) {
        db.on('save', function(collection, snapshot) {
          if (snapshot.v !== 4) return;

          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 1, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.equal(undefined);
              next();
            },
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 2, next);
            },
            function(snapshot, next) {
              expect(snapshot.v).to.equal(2);
              next();
            },
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 3, next);
            },
            function(snapshot, next) {
              expect(snapshot.v).to.equal(2);
              next();
            },
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 4, next);
            },
            function(snapshot, next) {
              expect(snapshot.v).to.equal(4);
              next();
            },
            done
          ]);
        });

        var doc = backend.connect().get('books', 'catcher-in-the-rye');

        util.callInSeries([
          function(next) {
            doc.create({title: 'Catcher in the Rye'}, next);
          },
          function(next) {
            doc.submitOp({p: ['author'], oi: 'J.F.Salinger'}, next);
          },
          function(next) {
            doc.submitOp({p: ['author'], od: 'J.F.Salinger', oi: 'J.D.Salinger'}, next);
          },
          function(next) {
            doc.submitOp({p: ['author'], od: 'J.D.Salinger', oi: 'J.D. Salinger'}, next);
          }
        ]);
      });

      it('can have the saving logic overridden in middleware', function(done) {
        backend.use('commit', function(request, callback) {
          request.saveMilestoneSnapshot = request.snapshot.v >= 3;
          callback();
        });

        db.on('save', function(collection, snapshot) {
          if (snapshot.v !== 4) return;

          util.callInSeries([
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 1, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.equal(undefined);
              next();
            },
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 2, next);
            },
            function(snapshot, next) {
              expect(snapshot).to.equal(undefined);
              next();
            },
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 3, next);
            },
            function(snapshot, next) {
              expect(snapshot.v).to.equal(3);
              next();
            },
            function(next) {
              db.getMilestoneSnapshot('books', 'catcher-in-the-rye', 4, next);
            },
            function(snapshot, next) {
              expect(snapshot.v).to.equal(4);
              next();
            },
            done
          ]);
        });

        var doc = backend.connect().get('books', 'catcher-in-the-rye');

        util.callInSeries([
          function(next) {
            doc.create({title: 'Catcher in the Rye'}, next);
          },
          function(next) {
            doc.submitOp({p: ['author'], oi: 'J.F.Salinger'}, next);
          },
          function(next) {
            doc.submitOp({p: ['author'], od: 'J.F.Salinger', oi: 'J.D.Salinger'}, next);
          },
          function(next) {
            doc.submitOp({p: ['author'], od: 'J.D.Salinger', oi: 'J.D. Salinger'}, next);
          }
        ]);
      });
    });
  });
};