From a72e25c8cd4260e646de78a205cbfba5c78b1462 Mon Sep 17 00:00:00 2001
From: Braydon Fuller <braydon@storj.io>
Date: Mon, 13 Nov 2017 16:33:41 -0500
Subject: [PATCH] Add locking to cron model

---
 lib/models/cron.js | 103 +++++++++++++++++++++++++++++++-------
 test/cron.unit.js  | 122 +++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 207 insertions(+), 18 deletions(-)
 create mode 100644 test/cron.unit.js

diff --git a/lib/models/cron.js b/lib/models/cron.js
index 73e2ebff..9295ee9d 100644
--- a/lib/models/cron.js
+++ b/lib/models/cron.js
@@ -1,8 +1,7 @@
 'use strict';
 
+const assert = require('assert');
 const mongoose = require('mongoose');
-const SchemaOptions = require('../options');
-const errors = require('storj-service-error-types');
 
 const CronJob = new mongoose.Schema({
   name: {
@@ -13,18 +12,19 @@ const CronJob = new mongoose.Schema({
   },
   locked: {
     type: Boolean,
-    default: false
+    required: true
+  },
+  lockedEnd: {
+    type: Date,
     required: true
   },
   started: {
     type: Date,
-    default: Date.now,
     required: true
   },
   finished: {
     type: Date,
-    default: Date.now,
-    required: true
+    required: false
   },
   data: {
     type: String,
@@ -32,21 +32,88 @@ const CronJob = new mongoose.Schema({
   }
 });
 
-Partner.set('toObject', {
-  transform: function(doc, ret) {
-    ret.id = ret._id;
-    delete ret.__v;
-    delete ret._id;
+CronJob.statics.lock = function(name, expires, callback) {
+  const self = this;
+  const now = new Date();
+  const end = new Date(now.getTime() + expires);
+  assert(Number.isInteger(expires), 'Expires argument is expected');
+
+  function isDuplicate(err) {
+    return (err && err.code === 11000);
   }
-});
 
-Partner.set('toJSON', {
-  transform: function(doc, ret) {
-    ret.id = ret._id;
-    delete ret.__v;
-    delete ret._id;
+  function getLock(done) {
+    const query = {
+      name: name,
+      locked: false
+    };
+    const sort = {};
+    const update = {
+      $set: {
+        name: name,
+        locked: true,
+        lockedEnd: end,
+        started: now
+      }
+    };
+    const options = {
+      new: true,
+      upsert: true,
+      writeConcern: 'majority'
+    };
+    self.collection.findAndModify(query, sort, update, options, (err, res) => {
+      if (isDuplicate(err)) {
+        return done(null, false);
+      } else if (err) {
+        return done(err, false);
+      }
+      done(null, true, res);
+    });
   }
-});
+
+  function getLockFromExpired(done) {
+    console.log('NOW', now);
+    const query = {
+      name: name,
+      locked: true,
+      lockedEnd: {
+        $lte: now
+      }
+    };
+    const sort = {};
+    const update = {
+      $set: {
+        name: name,
+        locked: true,
+        lockedEnd: end,
+        started: now
+      }
+    };
+    const options = {
+      new: true,
+      upsert: true,
+      writeConcern: 'majority'
+    };
+    self.collection.findAndModify(query, sort, update, options, (err, res) => {
+      if (isDuplicate(err)) {
+        return done(null, false);
+      } else if (err) {
+        return done(err, false);
+      }
+      done(null, true, res);
+    });
+  }
+
+  getLock((err, success, res) => {
+    if (err) {
+      return callback(err);
+    }
+    if (!success) {
+      return getLockFromExpired(callback);
+    }
+    callback(err, success, res);
+  });
+};
 
 module.exports = function(connection) {
   return connection.model('CronJob', CronJob);
diff --git a/test/cron.unit.js b/test/cron.unit.js
new file mode 100644
index 00000000..d03d6106
--- /dev/null
+++ b/test/cron.unit.js
@@ -0,0 +1,122 @@
+'use strict';
+
+const chai = require('chai');
+const expect = chai.expect;
+const sinon = require('sinon');
+const chaiDate = require('chai-datetime');
+const mongoose = require('mongoose');
+
+chai.use(chaiDate);
+require('mongoose-types').loadTypes(mongoose);
+
+const CronSchema = require('../lib/models/cron');
+
+var Cron;
+var connection;
+
+before(function(done) {
+  connection = mongoose.createConnection(
+    'mongodb://127.0.0.1:27017/__storj-bridge-test',
+    function() {
+      Cron = CronSchema(connection);
+      Cron.remove({}, function() {
+        done();
+      });
+    }
+  );
+});
+
+after(function(done) {
+  connection.close(done);
+});
+
+describe('/Storage/models/Cron', function() {
+  const sandbox = sinon.sandbox.create();
+  afterEach(() => sandbox.restore());
+
+  describe('@constructor', function() {
+
+    it('should create new work', function (done) {
+      const now = new Date();
+      const end = new Date(now.getTime() + 1000);
+      const job = new Cron({
+        name: 'StorageEventsFinality',
+        locked: true,
+        lockedEnd: end,
+        started: now
+      });
+
+      job.save(function(err, job) {
+        if (err) {
+          return done(err);
+        }
+
+        expect(job.name).to.equal('StorageEventsFinality');
+        expect(job.locked).to.equal(true);
+        expect(job.lockedEnd).to.equal(end);
+        expect(job.started).to.equal(now);
+        done();
+      });
+    });
+  });
+
+  describe('#lock', function () {
+
+    it('should get lock without document', function(done) {
+
+      Cron.lock('SingletonOne', 1000, function(err) {
+        if (err) {
+          return done(err);
+        }
+        done();
+      });
+
+    });
+
+    it('should not get lock with existing locked document', function(done) {
+
+      Cron.lock('SingletonTwo', 10000, function(err, locked) {
+        if (err) {
+          return done(err);
+        }
+        expect(locked).to.equal(true);
+
+        Cron.lock('SingletonTwo', 10000, function(err, locked) {
+          if (err) {
+            return done(err);
+          }
+          expect(locked).to.equal(false);
+          done();
+        });
+      });
+
+    });
+
+    it('should get lock with expired locked document', function(done) {
+      const now = new Date();
+      const clock = sandbox.useFakeTimers();
+      clock.tick(now.getTime());
+      const expires = 10000;
+
+      Cron.lock('SingletonThree', expires, function(err, locked, res) {
+        if (err) {
+          return done(err);
+        }
+        expect(locked).to.equal(true);
+        expect(res);
+        clock.tick(expires);
+
+        Cron.lock('SingletonThree', expires, function(err, locked, res) {
+          if (err) {
+            return done(err);
+          }
+          expect(locked).to.equal(true);
+          expect(res);
+          done();
+        });
+      });
+    });
+
+  });
+
+});