update URLs

client.js

@@ -1,59 +1,79 @@
 'use strict';
 
-/*global Promise*/
+// I'm not a fan of singletons (as they are EVIL).
+// However, this module is, by intent, meant to
+// represent a worker process in a cluster.
+// Thus, it is appropriately a singleton.
+var processWebSocket;
+var promiseWebSocket;
 
-var PromiseA = Promise;
-try {
-  PromiseA = require('bluebird').Promise;
-} catch(e) {
-  console.warn("For better Promise support please use bluebird");
-}
-// TODO iterate over the prototype
-// translate request / response
-var sqlite3real = require('sqlite3');
-
-/*
-function createConnection(opts) {
-  var server = ;
-
-  return server.create(opts).then(function () {
-    // created and listening
-  });
-}
-*/
-
-function startServer(opts) {
-  return require('./server').create(opts).then(function (server) {
+function startServer(opts, verbs, myServer) {
+  if (myServer) {
+    return verbs.Promise.resolve(myServer);
+  }
+  return require('./server').create(opts, verbs).then(function (server) {
     // this process doesn't need to connect to itself
     // through a socket
     return server.masterClient;
   });
 }
 
-function getConnection(opts) {
-  return new PromiseA(function (resolve) {
+// connection is scoped per-process, nothing more
+function getConnection(opts, verbs, mySocket, retry) {
+  function incr(ws) {
+    if (!ws.__count) {
+      ws.__count = 0;
+    }
+    ws.__count += 1;
+    return ws;
+  }
+  if (!retry && (mySocket || processWebSocket)) {
+    promiseWebSocket = verbs.Promise.resolve(mySocket || processWebSocket);
+    return promiseWebSocket.then(incr);
+  }
+
+  if (!retry && promiseWebSocket) {
+    return promiseWebSocket.then(incr);
+  }
+
+  promiseWebSocket = new verbs.Promise(function (resolve) {
     //setTimeout(function () {
       var WebSocket = require('ws');
-      var ws = new WebSocket('ws+unix:' + opts.sock);
+      // TODO how to include path and such?
+      // http://unix:/absolute/path/to/unix.socket:/request/path
+      // https://github.com/websockets/ws/issues/236
+      var ws;
+      var pathname = '/' + (require('cluster').worker||{}).id + '/' + opts.ipcKey;
+      var queryparams = {
+        ipcKey: opts.ipcKey
+      , ipc_key: opts.ipcKey
+      , worker_id: (require('cluster').worker||{}).id
+      };
+      var search = require('querystring').stringify(queryparams);
+      var wspath = 'ws+unix://' + opts.sock + ':' + pathname + '?' + search;
+      // https://github.com/websockets/ws/blob/master/doc/ws.md#unix-domain-sockets
+      // ws+unix:///absolule/path/to/uds_socket:/pathname?search_params
+      ws = new WebSocket(wspath);
 
       ws.on('error', function (err) {
         console.error('[ERROR] ws connection failed, retrying');
-        console.error(err);
+        console.error(err.stack || err);
 
         function retry() {
+          // TODO eventually throw up
           setTimeout(function () {
-            getConnection(opts).then(resolve, retry);
+            getConnection(opts, verbs, mySocket, true).then(resolve, retry);
           }, 100 + (Math.random() * 250));
         }
 
         if (!opts.connect && ('ENOENT' === err.code || 'ECONNREFUSED' === err.code)) {
           console.log('[NO SERVER] attempting to create a server #######################');
-          return startServer(opts).then(function (client) {
+          return startServer(opts, verbs).then(function (client) {
             // ws.masterClient = client;
             resolve({ masterClient: client });
           }, function (err) {
             console.error('[ERROR] failed to connect to sqlite3-cluster service. retrying...');
-            console.error(err);
+            console.error(err.stack || err);
             retry();
           });
         }
@@ -62,66 +82,276 @@ function getConnection(opts) {
       });
 
       ws.on('open', function () {
+
         resolve(ws);
       });
     //}, 100 + (Math.random() * 250));
-  });
-}
-
-function create(opts) {
-  if (!opts.sock) {
-    opts.sock = opts.filename + '.sock';
-  }
-
-  var promise;
-  var numcpus = require('os').cpus().length;
-  if (opts.standalone || (1 === numcpus && !opts.serve && !opts.connect)) {
-    return require('./wrapper').create(opts);
-  }
-
-  function retryServe() {
-    return startServer(opts).then(function (client) {
-      // ws.masterClient = client;
-      return { masterClient: client };
-    }, function (err) {
-      console.error('[ERROR] retryServe()');
-      console.error(err);
-      retryServe();
-    });
-  }
-
-  if (opts.serve) {
-    promise = retryServe();
-  } else {
-    promise = getConnection(opts);
-  }
-  /*
-  if (opts.connect) {
-  }
-  */
-
-  // TODO maybe use HTTP POST instead?
-  return promise.then(function (ws) {
-    if (ws.masterClient) {
-      return ws.masterClient;
+  }).then(function (ws) {
+    if (!processWebSocket) {
+      processWebSocket = ws;
     }
 
-    var db = {};
-    var proto = sqlite3real.Database.prototype;
-    var messages = [];
+    return ws;
+  });
 
-    function init(opts) {
-      return new PromiseA(function (resolve, reject) {
-        var id = Math.random();
+  return promiseWebSocket.then(incr);
+}
+
+module.exports.createClientFactory = function (conf, verbs, _socket) {
+  // TODO distinguish between defaults and mandates
+
+  if (!conf.ipcKey) {
+    throw new Error("[E_NO_IPCKEY] Your config must specify an ipcKey.");
+  }
+
+  return {
+    create: function (opts, _s) {
+      var copy = {};
+
+      if (_socket && _s) {
+        throw new Error("[E_USR_SOCKET] Your parent has decided that you may not choose your own SOCKET. Don't get mad at me, take it up with them.");
+      }
+      if (opts.key && conf.key) {
+        throw new Error("[E_USR_KEY] Your parent has decided that you may not choose your own KEY. Don't get mad at me, take it up with them.");
+      }
+      if (opts.algo && conf.algo) {
+        throw new Error("[E_USR_ALGO] Your parent has decided that you may not choose your own ALGO. Don't get mad at me, take it up with them.");
+      }
+      if (opts.bits && conf.bits) {
+        throw new Error("[E_USR_BITS] Your parent has decided that you may not choose your own BITS. Don't get mad at me, take it up with them.");
+      }
+      if (opts.dirname && conf.dirname) {
+        throw new Error("[E_USR_TENANT] Your parent has decided that you may not choose your own TENANT. Don't get mad at me, take it up with them.");
+      }
+      if (opts.tenant && conf.tenant) {
+        throw new Error("[E_USR_TENANT] Your parent has decided that you may not choose your own TENANT. Don't get mad at me, take it up with them.");
+      }
+      if (opts.prefix && conf.prefix) {
+        throw new Error("[E_USR_PREFIX] Your parent has decided that you may not choose your own PREFIX. Don't get mad at me, take it up with them.");
+      }
+      if (opts.suffix && conf.suffix) {
+        throw new Error("[E_USR_SUFFIX] Your parent has decided that you may not choose your own SUFFIX. Don't get mad at me, take it up with them.");
+      }
+      if (opts.ext && conf.ext) {
+        throw new Error("[E_USR_EXT] Your parent has decided that you may not choose your own EXT. Don't get mad at me, take it up with them.");
+      }
+      if (opts.serve) {
+        throw new Error("[E_USR_SERVE] Your parent have forbidden you to SERVE. Don't get mad at me, take it up with them.");
+      }
+      if (opts.sock && conf.sock) {
+        throw new Error("[E_USR_SERVE] Your parent have forbidden you to choose your own SOCK. Don't get mad at me, take it up with them.");
+      }
+
+      Object.keys(conf).forEach(function (key) {
+        copy[key] = conf[key];
+      });
+      Object.keys(opts).forEach(function (key) {
+        copy[key] = opts[key];
+      });
+
+      if (!verbs) {
+        verbs = {
+          Promise: null
+        };
+      }
+      if (!verbs.Promise) {
+        verbs.Promise = require('bluebird');
+      }
+
+      copy.connect = (require('cluster').worker && true);
+      copy.sock = conf.sock;
+      copy.tenant = conf.tenant;
+      copy.ipcKey = conf.ipcKey;
+      return module.exports.create(copy, verbs, _socket || _s || processWebSocket);
+    }
+  };
+};
+
+module.exports.create = function (opts, verbs, mySocket) {
+  if (!verbs) {
+    verbs = {};
+  }
+
+  var PromiseA = verbs && verbs.Promise || require('bluebird');
+  verbs.Promise = PromiseA;
+  // TODO iterate over the prototype
+  // translate request / response
+  var sqlite3real = require('sqlite3');
+
+  if (!mySocket) {
+    mySocket = processWebSocket;
+  }
+
+  function create(opts) {
+    function retryServe() {
+      return startServer(opts, verbs).then(function (client) {
+        // ws.masterClient = client;
+        return { masterClient: client };
+      }, function (err) {
+        console.error('[ERROR] retryServe()');
+        console.error(err.stack || err);
+        retryServe();
+      });
+    }
+
+    if (opts.serve) {
+      return retryServe(opts).then(function (servers) {
+        return servers.masterClient;
+      });
+    }
+
+    if (!opts.tenant) {
+      opts.tenant = "";
+    }
+    if (!opts.subtenant) {
+      opts.subtenant = "";
+    }
+    if (!opts.prefix) {
+      opts.prefix = '';
+    }
+    if (!opts.suffix) {
+      opts.suffix = '';
+    }
+    if (!opts.ext) {
+      opts.ext = '.sqlite3'; // also .sqlcipher
+    }
+    if (!opts.dbname) {
+      throw new Error("Please specify opts.dbname as the name of the database");
+    }
+
+
+    var promise;
+    var numcpus = require('os').cpus().length;
+
+    // if we're only on one core, use the lib directly, no socket
+    if (opts.standalone || (1 === numcpus && !opts.serve && !opts.connect)) {
+      return require('./wrapper').create(opts, verbs);
+    }
+
+    if (!opts.sock) {
+      throw new Error("Please specify opts.sock as the path to the master socket. '/tmp/sqlite3-cluster' would do nicely.");
+    }
+
+    promise = getConnection(opts, verbs, mySocket, true).then(function (socket) {
+      mySocket = socket;
+      return mySocket;
+    });
+
+    // TODO maybe use HTTP POST instead?
+    return promise.then(function (ws) {
+      var db = {};
+      var proto = sqlite3real.Database.prototype;
+      var messages = [];
+      var idprefix = require('crypto').randomBytes(12).toString('base64');
+      var idcount = 0;
+
+      function genId() {
+        idcount += 1;
+        return idprefix + idcount;
+      }
+
+      function init(iopts) {
+        //console.log('CLIENT INIT');
+        if (db._initPromise) {
+          return db._initPromise;
+        }
+
+        db._initPromise = new PromiseA(function (resolve, reject) {
+          // TODO needs to reject by a timeout
+          var id = genId();
+          ws.send(JSON.stringify({
+            type: 'init'
+          , args: [{
+            // encryption
+              bits: opts.bits || iopts.bits
+            , algorithm: opts.algo || opts.algorithm || iopts.algorithm || iopts.algo
+            , algo: opts.algo || opts.algorithm || iopts.algorithm || iopts.algo
+            , encmode: opts.mode || iopts.mode
+            }]
+          , func: 'init'
+            // db
+          , dirname: opts.dirname
+          , prefix: opts.prefix
+          , subtenant: opts.subtenant
+          , tenant: opts.tenant
+          , dbname: opts.dbname
+          , suffix: opts.suffix
+          , ext: opts.ext
+            // session
+          , id: id
+          }));
+
+          function onMessage(data) {
+            var cmd;
+
+            try {
+              cmd = JSON.parse(data.toString('utf8'));
+            } catch(e) {
+              console.error('[ERROR] in client, from sql server parse json');
+              console.error(e.stack || e);
+              console.error(data);
+              console.error();
+
+              // ignore this message, it came out of order
+              return reject(new Error("suxors to rejexors parse"));
+            }
+
+            if (cmd.id !== id) {
+              // ignore this message, it came out of order
+              return;
+            }
+
+            if (cmd.self) {
+              cmd.args = [db];
+            }
+
+            messages.splice(messages.indexOf(onMessage), 1);
+
+            if ('error' === cmd.type) {
+              //console.log('ERROR ARGS');
+              //console.log(cmd);
+              reject(cmd.args[0]);
+              return;
+            }
+
+            //console.log('CLIENT RESOLVING INIT');
+            resolve(cmd.args[0]);
+            return;
+          }
+
+          messages.push(onMessage);
+        });
+
+        return db._initPromise;
+      }
+
+      function rpcThunk(fname, args) {
+        var id;
+        var cb;
+
+        if ('function' === typeof args[args.length - 1]) {
+          id = genId();
+          cb = args.pop();
+        }
 
         ws.send(JSON.stringify({
-          type: 'init'
-        , args: [opts]
-        , func: 'init'
-        , filename: opts.filename
+          type: 'rpc'
+        , func: fname
+        , args: args
+        , dirname: opts.dirname
+        , prefix: opts.prefix
+        , subtenant: opts.subtenant
+        , tenant: opts.tenant
+        , dbname: opts.dbname
+        , suffix: opts.suffix
+        , ext: opts.ext
         , id: id
         }));
 
+        if (!cb) {
+          return;
+        }
+
         function onMessage(data) {
           var cmd;
 
@@ -129,7 +359,7 @@ function create(opts) {
             cmd = JSON.parse(data.toString('utf8'));
           } catch(e) {
             console.error('[ERROR] in client, from sql server parse json');
-            console.error(e);
+            console.error(e.stack || e);
             console.error(data);
             console.error();
 
@@ -138,119 +368,77 @@ function create(opts) {
           }
 
           if (cmd.id !== id) {
+            // ignore this message, it probably came out of order
             return;
           }
 
           if (cmd.self) {
             cmd.args = [db];
           }
+          //console.log('RESOLVING RPC', cmd.this, cmd.args);
+          cb.apply(cmd.this, cmd.args);
 
-          messages.splice(messages.indexOf(onMessage), 1);
-
-          if ('error' === cmd.type) {
-            reject(cmd.args[0]);
-            return;
+          if ('on' !== fname) {
+            var index = messages.indexOf(onMessage);
+            messages.splice(index, 1);
           }
-          resolve(cmd.args[0]);
         }
 
         messages.push(onMessage);
-      });
-    }
-
-    function rpcThunk(fname, args) {
-      var id;
-      var cb;
-
-      if ('function' === typeof args[args.length - 1]) {
-        id = Math.random();
-        cb = args.pop();
       }
 
-      ws.send(JSON.stringify({
-        type: 'rpc'
-      , func: fname
-      , args: args
-      , filename: opts.filename
-      , id: id
-      }));
+      db.sanitize = require('./wrapper').sanitize;
+      db.escape = require('./wrapper').escape;
 
-      if (!cb) {
-        return;
-      }
+      // TODO get methods from server (cluster-store does this)
+      // instead of using the prototype
+      Object.keys(sqlite3real.Database.prototype).forEach(function (key) {
 
-      function onMessage(data) {
-        var cmd;
-
-        try {
-          cmd = JSON.parse(data.toString('utf8'));
-        } catch(e) {
-          console.error('[ERROR] in client, from sql server parse json');
-          console.error(e);
-          console.error(data);
-          console.error();
-
-          //ws.send(JSON.stringify({ type: 'error', value: { message: e.message, code: "E_PARSE_JSON" } }));
-          return;
-        }
-
-        if (cmd.id !== id) {
-          return;
-        }
-
-        if (cmd.self) {
-          cmd.args = [db];
-        }
-        cb.apply(cmd.this, cmd.args);
-
-        if ('on' !== fname) {
-          var index = messages.indexOf(onMessage);
-          messages.splice(index, 1);
-        }
-      }
-
-      messages.push(onMessage);
-    }
-
-    db.sanitize = require('./wrapper').sanitize;
-    db.escape = require('./wrapper').escape;
-
-    // TODO get methods from server (cluster-store does this)
-    // instead of using the prototype
-    Object.keys(sqlite3real.Database.prototype).forEach(function (key) {
-
-      if ('function' === typeof proto[key]) {
-        db[key] = function () {
-          rpcThunk(key, Array.prototype.slice.call(arguments));
-        };
-      }
-    });
-
-    db.init = init;
-
-    ws.on('message', function (data) {
-      messages.forEach(function (fn) {
-        try {
-          fn(data);
-        } catch(e) {
-          console.error("[ERROR] ws.on('message', fn) (multi-callback)");
-          console.error(e);
-          // ignore
+        if ('function' === typeof proto[key]) {
+          db[key] = function () {
+            rpcThunk(key, Array.prototype.slice.call(arguments));
+          };
         }
       });
+
+      db.init = init;
+
+      ws.on('message', function (data) {
+        messages.forEach(function (fn) {
+          try {
+            fn(data);
+          } catch(e) {
+            console.error("[ERROR] ws.on('message', fn) (multi-callback)");
+            console.error(e.stack || e);
+            // ignore
+          }
+        });
+      });
+
+      // serialize
+      // parallel
+      db.serialize = db.parallel = function () {
+        throw new Error('NOT IMPLEMENTED in SQLITE3-remote');
+      };
+
+      db.close = function (fn) {
+        ws.__count -= 1;
+        if (!ws.__count) {
+          // waiting for https://github.com/websockets/ws/issues/613 to land
+          // 1000 means 'normal' https://github.com/websockets/ws/blob/master/lib/ErrorCodes.js
+          ws.close(1000, null, fn);
+        }
+      };
+
+      if (opts.init) {
+        return db.init(opts);
+      }
+      return db;
     });
+  }
 
-    // serialize
-    // parallel
-    db.serialize = db.parallel = function () {
-      throw new Error('NOT IMPLEMENTED in SQLITE3-remote');
-    };
-
-    return db;
-  });
-}
-
+  return create(opts);
+};
 
 module.exports.sanitize = require('./wrapper').sanitize;
 module.exports.escape = require('./wrapper').escape;
-module.exports.create = create;

cluster.js

@@ -20,3 +20,5 @@ function create(opts) {
 module.exports.sanitize = sqlite3.sanitize;
 module.exports.escape = sqlite3.escape;
 module.exports.create = create;
+module.exports.createServer = sqlite3.createServer;
+module.exports.createMasterClient = sqlite3.createMasterClient;

examples/cluster/index.js

@@ -0,0 +1,8 @@
+var cluster = require('cluster');
+
+if (cluster.isMaster) {
+  require('./master');
+}
+else {
+  require('./worker');
+}

examples/cluster/master.js

@@ -0,0 +1,56 @@
+'use strict';
+
+var cluster = require('cluster');
+var minCores = 2;
+var numCores = Math.max(minCores, require('os').cpus().length);
+var i;
+
+function run(connect, ipcKey) {
+  var sqlite3 = require('../../cluster');
+
+  return sqlite3.create({
+    bits: 128
+  , dirname: '/tmp/'
+  , prefix: 'foobar.'
+  , dbname: 'cluster'
+  , suffix: '.test'
+  , ext: '.sqlcipher'
+  , verbose: null
+  , standalone: null
+  , serve: !connect
+  , connect: connect
+  , sock: '/tmp/foobar.sqlite3-cluster.test.sock'
+  , ipcKey: ipcKey
+  });
+}
+
+var ipcKey = require('crypto').randomBytes(16).toString('hex');
+// not a bad idea to setup the master before forking the workers
+
+run(false, ipcKey).then(function () {
+  var w;
+
+  function setupWorker(w) {
+    function sendKey() {
+      w.send({ ipcKey: ipcKey });
+    }
+    w.on('online', sendKey);
+  }
+
+  for (i = 1; i <= numCores; i += 1) {
+    w = cluster.fork();
+    setupWorker(w);
+  }
+});
+
+process.on('beforeExit', function () {
+  console.log("[MASTER] I've got nothing left to live for... ugh... death is upon me...");
+});
+// The native Promise implementation ignores errors because... dumbness???
+process.on('unhandledRejection', function (err) {
+  console.error('Unhandled Promise Rejection');
+  console.error(err);
+  console.error(err.stack);
+
+  process.exit(1);
+});

examples/cluster/worker.js

@@ -0,0 +1,122 @@
+'use strict';
+
+var cluster = require('cluster');
+
+function testSelect(client) {
+  var PromiseA = require('bluebird');
+
+  return new PromiseA(function (resolve, reject) {
+    client.run('CREATE TABLE IF NOT EXISTS meta (version TEXT)', function (err) {
+      if (err) {
+        console.error('[ERROR]', cluster.isMaster && '0' || cluster.worker.id);
+        console.error(err.stack);
+        reject(err);
+        return;
+      }
+
+      client.get("SELECT version FROM meta", [], function (err, result) {
+        if (err) {
+          console.error('[ERROR] create table', cluster.isMaster && '0' || cluster.worker.id);
+          console.error(err);
+          reject(err);
+          return;
+        }
+
+        console.log('[this] Worker #', cluster.isMaster && '0' || cluster.worker.id);
+        console.log(this);
+
+        console.log('[result] Worker #', cluster.isMaster && '0' || cluster.worker.id);
+        console.log(result);
+
+        resolve(client);
+      });
+    });
+  });
+}
+
+function init(ipcKey) {
+  var sqlite3 = require('../../cluster');
+
+  return sqlite3.create({
+      bits: 128
+    , dirname: '/tmp/'
+    , prefix: 'foobar.'
+    , dbname: 'cluster'
+    , suffix: '.test'
+    , ext: '.sqlcipher'
+    , verbose: null
+    , standalone: null
+    , serve: null
+    , connect: true
+    , sock: '/tmp/foobar.sqlite3-cluster.test.sock'
+    , ipcKey: ipcKey
+  }).then(function (client) {
+    //console.log('[INIT] begin');
+    return client.init({ algorithm: 'aes', bits: 128, key: '00000000000000000000000000000000' }).then(function (args) {
+      //console.log('[INIT]', args);
+      return client;
+    });
+  });
+}
+
+function run(connect, ipcKey) {
+  var sqlite3 = require('../../cluster');
+
+  return sqlite3.create({
+      bits: 128
+    , dirname: '/tmp/'
+    , prefix: 'foobar.'
+    , dbname: 'cluster'
+    , suffix: '.test'
+    , ext: '.sqlcipher'
+    , verbose: null
+    , standalone: null
+    , serve: !connect
+    , connect: connect
+    , sock: '/tmp/foobar.sqlite3-cluster.test.sock'
+    , ipcKey: ipcKey
+  });//.then(testSelect);
+}
+
+function onMessage(msg) {
+  function loseTheWillToLive() {
+    process.removeListener('message', onMessage);
+    // child processes do not exit when their event loop is empty
+    process.nextTick(function () {
+      process.exit(0);
+    });
+  }
+
+  console.log('New Worker', cluster.worker.id, msg);
+  if (1 === cluster.worker.id) {
+    init(msg.ipcKey).then(testSelect).then(function (client) {
+      console.log('init worker closing...');
+      setTimeout(function () {
+        client.close(loseTheWillToLive);
+        loseTheWillToLive();
+      }, 1000);
+      // waiting for https://github.com/websockets/ws/issues/613 to land
+    });
+  } else {
+    setTimeout(function () {
+      run(true, msg.ipcKey).then(testSelect).then(function (client) {
+        console.log('other working closing...');
+        client.close(loseTheWillToLive);
+        loseTheWillToLive();
+      });
+    }, 100);
+  }
+}
+process.on('message', onMessage);
+
+// The native Promise implementation ignores errors because... dumbness???
+process.on('beforeExit', function () {
+  console.log("[WORKER] I've got nothing left to do");
+});
+process.on('unhandledRejection', function (err) {
+  console.error('Unhandled Promise Rejection');
+  console.error(err);
+  console.error(err.stack);
+
+  process.exit(1);
+});

examples/cluster2/index.js

@@ -0,0 +1,8 @@
+var cluster = require('cluster');
+
+if (cluster.isMaster) {
+  require('./master');
+}
+else {
+  require('./worker');
+}

examples/cluster2/master.js

@@ -0,0 +1,51 @@
+'use strict';
+
+var cluster = require('cluster');
+var minCores = 3;
+var numCores = Math.max(minCores, require('os').cpus().length);
+var i;
+var sock = '/tmp/foobar.sqlite3-cluster.test.sock';
+
+function run(connect, ipcKey) {
+  var sqlite3 = require('../../cluster');
+
+  return sqlite3.create({
+    verbose: null
+  , standalone: null
+  , serve: sock
+  , connect: null
+  , sock: sock 
+  , ipcKey: ipcKey
+  });
+}
+
+var ipcKey = require('crypto').randomBytes(16).toString('hex');
+// not a bad idea to setup the master before forking the workers
+
+run(false, ipcKey).then(function () {
+  var w;
+
+  function setupWorker(w) {
+    function sendKey() {
+      w.send({ ipcKey: ipcKey, sock: sock });
+    }
+    w.on('online', sendKey);
+  }
+
+  for (i = 1; i <= numCores; i += 1) {
+    w = cluster.fork();
+    setupWorker(w);
+  }
+});
+
+process.on('beforeExit', function () {
+  console.log("[MASTER] I've got nothing left to live for... ugh... death is upon me...");
+});
+// The native Promise implementation ignores errors because... dumbness???
+process.on('unhandledRejection', function (err) {
+  console.error('Unhandled Promise Rejection');
+  console.error(err);
+  console.error(err.stack);
+
+  process.exit(1);
+});

examples/cluster2/worker.js

@@ -0,0 +1,118 @@
+'use strict';
+
+var cluster = require('cluster');
+
+console.log("[Worker #" + cluster.worker.id + "]");
+
+function testSelect(client) {
+  var PromiseA = require('bluebird');
+
+  return new PromiseA(function (resolve, reject) {
+    client.run('CREATE TABLE IF NOT EXISTS meta (version TEXT)', function (err) {
+      if (err) {
+        if ('E_NO_INIT' === err.code) {
+          console.error(err.message);
+          resolve(client);
+          return;
+        }
+
+        reject(err);
+        return;
+      }
+
+      client.get("SELECT version FROM meta", [], function (err, result) {
+        if (err) {
+          console.error('[ERROR] create table', cluster.isMaster && '0' || cluster.worker.id);
+          console.error(err.stack || err);
+          reject(err);
+          return;
+        }
+
+        console.log('[this] Worker #', cluster.isMaster && '0' || cluster.worker.id);
+        console.log(this);
+
+        console.log('[result] Worker #', cluster.isMaster && '0' || cluster.worker.id);
+        console.log(result);
+
+        resolve(client);
+      });
+    });
+  });
+}
+
+function run(ipcKey, sock) {
+  var sqlite3 = require('../../cluster');
+
+  return sqlite3.create({
+      bits: 128
+    , dirname: '/tmp/'
+    , prefix: 'foobar.'
+    , dbname: 'cluster'
+    , suffix: '.test'
+    , ext: '.sqlcipher'
+    , verbose: null
+    , standalone: null
+    , serve: null
+    , connect: sock
+    , sock: sock
+    , ipcKey: ipcKey
+  });
+}
+
+function init(client) {
+  //console.log('[INIT] begin');
+  return client.init({
+    algorithm: 'aes'
+  , bits: 128
+  , mode: 'cbc'
+  , key: '00000000000000000000000000000000'
+  }).then(function (/*args*/) {
+    //console.log('[INIT]', args);
+    return client;
+  });
+}
+
+function onMessage(msg) {
+  function loseTheWillToLive() {
+    process.removeListener('message', onMessage);
+    // child processes do not exit when their event loop is empty
+    setTimeout(function () {
+      console.log('#' + cluster.worker.id + ' dead');
+      process.exit(0);
+    }, 100);
+  }
+
+  console.log('New Worker', cluster.worker.id, msg);
+  if (1 === cluster.worker.id) {
+    //setTimeout(function () {
+      run(msg.ipcKey, msg.sock).then(testSelect).then(function (client) {
+        setTimeout(function () {
+          console.log('init worker closing...');
+          client.close(loseTheWillToLive);
+          loseTheWillToLive();
+        }, 1000);
+        // waiting for https://github.com/websockets/ws/issues/613 to land
+      });
+    //}, 1000);
+  } else {
+    setTimeout(function () {
+      run(msg.ipcKey, msg.sock).then(init).then(testSelect).then(function (client) {
+        console.log('#' + cluster.worker.id + ' other working closing...');
+        client.close(loseTheWillToLive);
+        loseTheWillToLive();
+      });
+    }, 100 * cluster.worker.id);
+  }
+}
+process.on('message', onMessage);
+
+// The native Promise implementation ignores errors because... dumbness???
+process.on('beforeExit', function () {
+  console.log("[WORKER] I've got nothing left to do");
+});
+process.on('unhandledRejection', function (err) {
+  console.error('Unhandled Promise Rejection');
+  console.error(err.stack || err);
+
+  process.exit(1);
+});

examples/factory/index.js

@@ -0,0 +1,8 @@
+var cluster = require('cluster');
+
+if (cluster.isMaster) {
+  require('./master');
+}
+else {
+  require('./worker');
+}

examples/factory/master.js

@@ -0,0 +1,48 @@
+'use strict';
+
+var cluster = require('cluster');
+var minCores = 3;
+var numCores = Math.max(minCores, require('os').cpus().length);
+var i;
+var sock = '/tmp/foobar.sqlite3-cluster.test.sock';
+
+function run(connect, ipcKey) {
+  var sqlite3 = require('../../server');
+
+  return sqlite3.createServer({
+    verbose: null
+  , sock: sock 
+  , ipcKey: ipcKey
+  });
+}
+
+var ipcKey = require('crypto').randomBytes(16).toString('hex');
+// not a bad idea to setup the master before forking the workers
+
+run(false, ipcKey).then(function () {
+  var w;
+
+  function setupWorker(w) {
+    function sendKey() {
+      w.send({ ipcKey: ipcKey, sock: sock });
+    }
+    w.on('online', sendKey);
+  }
+
+  for (i = 1; i <= numCores; i += 1) {
+    w = cluster.fork();
+    setupWorker(w);
+  }
+});
+
+process.on('beforeExit', function () {
+  console.log("[MASTER] I've got nothing left to live for... ugh... death is upon me...");
+});
+// The native Promise implementation ignores errors because... dumbness???
+process.on('unhandledRejection', function (err) {
+  console.error('Unhandled Promise Rejection');
+  console.error(err);
+  console.error(err.stack);
+
+  process.exit(1);
+});

examples/factory/worker.js

@@ -0,0 +1,115 @@
+'use strict';
+
+var cluster = require('cluster');
+
+console.log("[Worker #" + cluster.worker.id + "]");
+
+function testSelect(client) {
+  var PromiseA = require('bluebird');
+
+  return new PromiseA(function (resolve, reject) {
+    client.run('CREATE TABLE IF NOT EXISTS meta (version TEXT)', function (err) {
+      if (err) {
+        if ('E_NO_INIT' === err.code) {
+          console.error(err.message);
+          resolve(client);
+          return;
+        }
+
+        reject(err);
+        return;
+      }
+
+      client.get("SELECT version FROM meta", [], function (err, result) {
+        if (err) {
+          console.error('[ERROR] create table', cluster.isMaster && '0' || cluster.worker.id);
+          console.error(err.stack || err);
+          reject(err);
+          return;
+        }
+
+        console.log('Worker #', (cluster.isMaster && '0' || cluster.worker.id), '[this], [result]:');
+        console.log(this);
+        console.log(result);
+
+        resolve(client);
+      });
+    });
+  });
+}
+
+function run(clientFactory) {
+  return clientFactory.create({
+      init: false
+    , dbname: 'factory.' + cluster.worker.id
+  });
+}
+
+function init(client) {
+  return client.init({
+    algorithm: 'aes'
+  , bits: 128
+  , mode: 'cbc'
+  , key: '00000000000000000000000000000000'
+  }).then(function (/*db*/) {
+    return client;
+  });
+}
+
+function onMessage(msg) {
+  function loseTheWillToLive() {
+    process.removeListener('message', onMessage);
+    // child processes do not exit when their event loop is empty
+    setTimeout(function () {
+      console.log('#' + cluster.worker.id + ' dead');
+      process.exit(0);
+    }, 100);
+  }
+
+  var clientFactory = require('../../client').createClientFactory({
+      algorithm: 'aes'
+    , bits: 128
+    , mode: 'cbc'
+    , dirname: '/tmp/'
+    , prefix: 'foobar.'
+    //, dbname: 'cluster'
+    , suffix: '.test'
+    , ext: '.sqlcipher'
+    , sock: msg.sock
+    , ipcKey: msg.ipcKey
+  });
+
+  console.log('New Worker', cluster.worker.id, msg);
+  if (1 === cluster.worker.id) {
+    //setTimeout(function () {
+      run(clientFactory).then(testSelect).then(function (client) {
+        setTimeout(function () {
+          console.log('init worker closing...');
+          client.close(loseTheWillToLive);
+          loseTheWillToLive();
+        }, 1000);
+        // waiting for https://github.com/websockets/ws/issues/613 to land
+      });
+    //}, 1000);
+  } else {
+    setTimeout(function () {
+      run(clientFactory).then(init).then(testSelect).then(function (client) {
+        console.log('#' + cluster.worker.id + ' other working closing...');
+        client.close(loseTheWillToLive);
+        loseTheWillToLive();
+      });
+    }, 100 * cluster.worker.id);
+  }
+}
+process.on('message', onMessage);
+
+// The native Promise implementation ignores errors because... dumbness???
+process.on('beforeExit', function () {
+  console.log("[WORKER] I've got nothing left to do");
+});
+process.on('unhandledRejection', function (err) {
+  console.error('Unhandled Promise Rejection');
+  console.error(err.stack || err);
+
+  process.exit(1);
+});

examples/standalone.js

@@ -1,17 +1,24 @@
 'use strict';
 
 function run() {
-  var sqlite3 = require('./standalone');
+  var sqlite3 = require('../standalone');
+  var promise;
 
-  sqlite3.create({
+  promise = sqlite3.create({
       key: '00000000000000000000000000000000'
     , bits: 128
-    , filename: '/tmp/test.cluster.sqlcipher'
+    , dirname: '/tmp/'
+    , prefix: 'foobar.'
+    , dbname: 'standalone'
+    , suffix: '.test'
+    , ext: '.sqlcipher'
     , verbose: null
     , standalone: true
     , serve: null
     , connect: null
-  }).then(function (client) {
+  });
+  
+  promise.then(function (client) {
     client.all("SELECT ?", ['Hello World!'], function (err, result) {
       if (err) {
         console.error('[ERROR] standalone');
@@ -31,7 +38,7 @@ function run() {
 run();
 
 // The native Promise implementation ignores errors because... dumbness???
-process.on('unhandledPromiseRejection', function (err) {
+process.on('unhandledRejection', function (err) {
   console.error('Unhandled Promise Rejection');
   console.error(err);
   console.error(err.stack);

package.json

@@ -1,6 +1,6 @@
 {
   "name": "sqlite3-cluster",
-  "version": "1.1.2",
+  "version": "2.1.2",
   "description": "A wrapper to enable the use of sqlite3 with node cluster via a socket server (i.e. for Raspberry Pi 2).",
   "main": "index.js",
   "scripts": {
@@ -9,7 +9,7 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/coolaj86/sqlite3-cluster.git"
+    "url": "git+https://git.coolaj86.com/coolaj86/sqlite3-cluster.js.git"
   },
   "keywords": [
     "sqlite3",
@@ -18,14 +18,14 @@
     "cluster",
     "rpi2"
   ],
-  "author": "AJ ONeal <coolaj86@gmail.com> (http://coolaj86.com/)",
-  "license": "Apache-2.0",
+  "author": "AJ ONeal <coolaj86@gmail.com> (https://coolaj86.com/)",
+  "license": "(MIT OR Apache-2.0)",
   "bugs": {
-    "url": "https://github.com/coolaj86/sqlite3-cluster/issues"
+    "url": "https://git.coolaj86.com/coolaj86/sqlite3-cluster.js/issues"
   },
-  "homepage": "https://github.com/coolaj86/sqlite3-cluster#readme",
+  "homepage": "https://git.coolaj86.com/coolaj86/sqlite3-cluster.js",
   "dependencies": {
     "sqlite3": "^3.0.9",
-    "ws": "^0.7.2"
+    "ws": "^2.3.1"
   }
 }

server.js

@@ -1,55 +1,90 @@
 'use strict';
-/*global Promise*/
 
-var PromiseA = Promise;
-try {
-  PromiseA = require('bluebird').Promise;
-} catch(e) {
-  console.warn("For better Promise support please use bluebird");
-}
+var PromiseA = require('bluebird').Promise;
 var wsses = {};
 
-function createApp(server, options) {
+function createApp(servers, options) {
+  var url = require('url');
+  var wss = servers.wss;
+  //var server = servers.server;
 
-  if (wsses[options.filename]) {
-    return PromiseA.resolve(wsses[options.filename]);
+  //var express = require('express');
+  //var app = express();
+  /*
+  function app(req, res) {
+    res.end('NOT IMPLEMENTED');
   }
+  */
 
-  return require('./wrapper').create(options).then(function (db) {
+  wss.on('connection', function (ws) {
+    var location = url.parse(ws.upgradeReq.url, true);
+    // you might use location.query.access_token to authenticate or share sessions
+    // or ws.upgradeReq.headers.cookie (see http://stackoverflow.com/a/16395220/151312
 
-    var url = require('url');
-    //var express = require('express');
-    //var app = express();
-    var wss = server.wss;
-
-    function app(req, res) {
-      res.end('NOT IMPLEMENTED');
+    if (!options.ipcKey) {
+      console.warn("[S] [SECURITY] please include { ipcKey: crypto.randomBytes(16).toString('base64') }"
+        + " in your options and pass it from master to worker processes with worker.send()");
+      ws._authorized = true;
+    } else {
+      ws._authorized = (options.ipcKey === (location.query.ipcKey || location.query.ipc_key));
     }
 
-    wss.on('connection', function (ws) {
+    if (!ws._authorized) {
+      ws.send(JSON.stringify({ error: { message: "Unauthorized: ipc_key does not match", code: 'E_UNAUTHORIZED_IPCKEY' } }));
+      ws.close();
+      return;
+    }
 
-      var location = url.parse(ws.upgradeReq.url, true);
-      // you might use location.query.access_token to authenticate or share sessions
-      // or ws.upgradeReq.headers.cookie (see http://stackoverflow.com/a/16395220/151312
+    if (!wss.__count) {
+      wss.__count = 0;
+    }
+    wss.__count += 1;
 
-      ws.__session_id = location.query.session_id || Math.random();
+    function decrWs() {
+      wss.__count -= 1;
+      if (!wss.__count) {
+        console.log('[S] client count is zero, but server will be left open');
+        /*
+        wss.close(function () {
+          console.log('wss.closed');
+        });
+        server.close(function () {
+          console.log('server closed, but will not exit due to bug? in wss.close()');
+          process.exit(0);
+        });
+        */
+      }
+    }
 
-      ws.on('message', function (buffer) {
-        var cmd;
+    ws.on('error', function (err) {
+      console.error('[S] [WebSocket error]');
+      console.error(err.stack);
+      decrWs();
+    });
+    ws.on('close', decrWs);
+    ws.on('message', function (buffer) {
+      var cmd;
+      var promise;
 
-        try {
-          cmd = JSON.parse(buffer.toString('utf8'));
-        } catch(e) {
-          console.error('[ERROR] parse json');
-          console.error(e);
-          console.error(buffer);
-          console.error();
-          ws.send(JSON.stringify({ type: 'error', value: { message: e.message, code: "E_PARSE_JSON" } }));
-          return;
-        }
+      try {
+        cmd = JSON.parse(buffer.toString('utf8'));
+      } catch(e) {
+        console.error('[S] [ERROR] parse json');
+        console.error(e.stack || e);
+        console.error(buffer);
+        console.error();
+        ws.send(JSON.stringify({ type: 'error', value: { message: e.message, code: "E_PARSE_JSON" } }));
+        return;
+      }
+
+      //console.log('cmd');
+      //console.log(cmd);
+      // caching and create logic happens in the wrapper stored here below
+      promise = require('./wrapper').create(cmd && cmd.dbname && cmd || options).then(function (db) {
 
         switch(cmd.type) {
           case 'init':
+            //console.log('[S] init', cmd);
             db[cmd.func].apply(db, cmd.args).then(function () {
               var args = Array.prototype.slice.call(arguments);
               var myself;
@@ -59,6 +94,7 @@ function createApp(server, options) {
                 myself = true;
               }
 
+              //console.log('[INIT HAPPENING]');
               ws.send(JSON.stringify({
                 id: cmd.id
               , self: myself
@@ -69,12 +105,13 @@ function createApp(server, options) {
             break;
 
           case 'rpc':
-            if (!db._initialized) {
+            if ('close' !== cmd.func && !db._initialized) {
+              //console.log('[RPC NOT HAPPENING]');
               ws.send(JSON.stringify({
                 type: 'error'
               , id: cmd.id
-              , args: [{ message: 'database has not been initialized' }]
-              , error: { message: 'database has not been initialized' }
+              , args: [{ message: 'database has not been initialized', code: 'E_NO_INIT' }]
+              , error: { message: 'database has not been initialized', code: 'E_NO_INIT' }
               }));
               return;
             }
@@ -88,6 +125,7 @@ function createApp(server, options) {
                 myself = true;
               }
 
+              //console.log('[RPC HAPPENING]', args, cmd.id);
               ws.send(JSON.stringify({
                 this: (!err && this !== global) ? this : {}
               , args: args
@@ -106,42 +144,80 @@ function createApp(server, options) {
         }
 
       });
-
-      ws.send(JSON.stringify({ type: 'session', value: ws.__session_id }));
     });
+  });
 
-    app.masterClient = db;
-    wsses[options.filename] = app;
+  // wsses[options.sock] = app;
+  return PromiseA.resolve();
+}
 
-    return app;
+function newSocket(options) {
+  if (wsses[options.sock]) {
+    return PromiseA.resolve(wsses[options.sock]);
+  }
+
+  wsses[options.sock] = new PromiseA(function (resolve) {
+    var fs = require('fs');
+    fs.unlink(options.sock, function () {
+      var server = require('http').createServer();
+      // ignore error when socket doesn't exist
+      server.listen(options.sock, function () {
+        resolve(server);
+      });
+    });
+  }).then(function (server) {
+    var WebSocketServer = require('ws').Server;
+    var servers = {
+      server: require('http').createServer()
+    , wss: new WebSocketServer({ server: server })
+    };
+    
+    return createApp(servers, options).then(function (/*app*/) {
+      // server.on('request', app);
+      wsses[options.sock] = servers;
+
+      return wsses[options.sock];
+    });
+  });
+
+  return wsses[options.sock];
+}
+
+function createMasterClient(options) {
+  return require('./wrapper').create(options, null).then(function (db) {
+    return db;
+  });
+}
+
+function createServer(options) {
+  if (!options.sock) {
+    throw new Error("Please provide options.sock as the socket to serve from");
+  }
+  options.server = options.sock;
+
+  return newSocket(options).then(function () {
+    var result = {};
+
+    Object.keys(wsses[options.sock]).forEach(function (key) {
+      result[key] = wsses[options.sock][key];
+    });
   });
 }
 
 function create(options) {
-  var server = require('http').createServer();
-  var WebSocketServer = require('ws').Server;
-  var wss = new WebSocketServer({ server: server });
-  //var port = process.env.PORT || process.argv[0] || 4080;
+  return createServer(options).then(function (result) {
+    if (!options.dbname) {
+      return result;
+    }
 
-  var fs = require('fs');
-  var ps = [];
+    return createMasterClient(options).then(function (db) {
+      result.masterClient = db;
 
-  ps.push(new PromiseA(function (resolve) {
-    fs.unlink(options.sock, function () {
-      // ignore error when socket doesn't exist
-
-      server.listen(options.sock, resolve);
+      return result;
     });
-  }));
-
-  ps.push(createApp({ server: server, wss: wss }, options).then(function (app) {
-    server.on('request', app);
-    return { masterClient: app.masterClient };
-  }));
-
-  return PromiseA.all(ps).then(function (results) {
-    return results[1];
   });
 }
 
 module.exports.create = create;
+module.exports.createMasterClient = createMasterClient;
+module.exports.createServer = createServer;

test-cluster.js

@@ -1,95 +0,0 @@
-'use strict';
-
-var cluster = require('cluster');
-//var numCores = 2;
-var numCores = require('os').cpus().length;
-var i;
-
-function testSelect(client) {
-  return client.run('CREATE TABLE IF NOT EXISTS meta (version TEXT)', function (err) {
-    if (err) {
-      console.error('[ERROR] create table', cluster.isMaster && '0' || cluster.worker.id);
-      console.error(err);
-      return;
-    }
-
-    return client.get("SELECT version FROM meta", [], function (err, result) {
-
-      if (err) {
-        console.error('[ERROR]', cluster.isMaster && '0' || cluster.worker.id);
-        console.error(err);
-        return;
-      }
-
-      console.log('[this]', cluster.isMaster && '0' || cluster.worker.id);
-      console.log(this);
-
-      console.log('[result]', cluster.isMaster && '0' || cluster.worker.id);
-      console.log(result);
-    });
-  });
-}
-
-function init() {
-  var sqlite3 = require('./cluster');
-
-  return sqlite3.create({
-      bits: 128
-    , filename: '/tmp/test.cluster.sqlcipher'
-    , verbose: null
-    , standalone: null
-    , serve: null
-    , connect: null
-  }).then(function (client) {
-    console.log('[INIT] begin');
-    return client.init({ bits: 128, key: '00000000000000000000000000000000' });
-  }).then(testSelect, function (err) {
-    console.error('[ERROR]');
-    console.error(err);
-  }).then(function () {
-    console.log('success');
-  }, function (err) {
-    console.error('[ERROR 2]');
-    console.error(err);
-  });
-}
-
-function run() {
-  var sqlite3 = require('./cluster');
-
-  return sqlite3.create({
-      bits: 128
-    , filename: '/tmp/test.cluster.sqlcipher'
-    , verbose: null
-    , standalone: null
-    , serve: null
-    , connect: null
-  });//.then(testSelect);
-}
-
-if (cluster.isMaster) {
-  // not a bad idea to setup the master before forking the workers
-  run().then(function () {
-    for (i = 1; i <= numCores; i += 1) {
-      cluster.fork();
-    }
-  });
-} else {
-  if (1 === cluster.worker.id) {
-    init().then(testSelect);
-    return;
-  } else {
-    setTimeout(function () {
-      run().then(testSelect);
-    }, 100);
-  }
-}
-
-// The native Promise implementation ignores errors because... dumbness???
-process.on('unhandledPromiseRejection', function (err) {
-  console.error('Unhandled Promise Rejection');
-  console.error(err);
-  console.error(err.stack);
-
-  process.exit(1);
-});

wrapper.js

@@ -1,39 +1,42 @@
 'use strict';
 
-/*global Promise*/
-var PromiseA = Promise;
-try {
-  PromiseA = require('bluebird').Promise;
-} catch(e) {
-  console.warn("For better Promise support please use bluebird");
-}
 var sqlite3 = require('sqlite3');
+// TODO expire unused dbs from cache
 var dbs = {};
 
 function sanitize(str) {
   return String(str).replace("'", "''");
 }
 
-function create(opts) {
-  var db;
-
+function create(opts, verbs) {
+  if (!verbs) {
+    verbs = {};
+  }
   if (!opts) {
     opts = {};
   }
 
-  if (opts.verbose) {
-    sqlite3.verbose();
+  var db;
+  var PromiseA = verbs.Promise || require('bluebird');
+  var dbname = "";
+
+  dbname += (opts.prefix || '');
+  if (opts.subtenant) {
+    dbname += opts.subtenant + '.';
   }
-
-  if (!dbs[opts.filename]) {
-    dbs[opts.filename] = new sqlite3.Database(opts.filename);
+  if (opts.tenant) {
+    dbname += opts.tenant + '.';
   }
+  dbname += (opts.dbname || '');
+  dbname += (opts.suffix || '');
+  dbname += (opts.ext || '');
+  dbname = require('path').resolve(opts.dirname || '', dbname);
 
-  db = dbs[opts.filename];
-  db.sanitize = sanitize;
-  db.escape = sanitize;
+  function initDb(newOpts) {
+    if (dbs[dbname].initPromise) {
+      return dbs[dbname].initPromise;
+    }
 
-  db.init = function (newOpts) {
     if (!newOpts) {
       newOpts = {};
     }
@@ -41,23 +44,25 @@ function create(opts) {
     var key = newOpts.key || opts.key;
     var bits = newOpts.bits || opts.bits;
 
-    return new PromiseA(function (resolve, reject) {
-      if (db._initialized) {
+    dbs[dbname].initPromise = new PromiseA(function (resolve, reject) {
+      if (dbs[dbname].db._initialized) {
         resolve(db);
         return;
       }
 
       if (!key) {
         if (!bits) {
-          db._initialized = true;
+          //console.log("INITIALIZED WITHOUT KEY");
+          //console.log(opts);
+          dbs[dbname].db._initialized = true;
         }
+        dbs[dbname].db = db;
         resolve(db);
         return;
       }
 
       // TODO test key length
 
-      db._initialized = true;
       db.serialize(function () {
         var setup = [];
 
@@ -83,13 +88,48 @@ function create(opts) {
 
         PromiseA.all(setup).then(function () {
           // restore original functions
+          dbs[dbname].db._initialized = true;
+          dbs[dbname].db = db;
+
           resolve(db);
         }, reject);
       });
     });
-  };
 
-  return db.init(opts);
+    return dbs[dbname].initPromise;
+  }
+
+  function newDb() {
+    // dbs[dbname] = db // 
+    db = new sqlite3.Database(dbname);
+    db.init = initDb;
+    db.sanitize = sanitize;
+    db.escape = sanitize;
+
+    if (opts.verbose) {
+      sqlite3.verbose();
+    }
+
+    return db;
+  }
+
+  // Could be any of:
+  //   * db object
+  //   * init promise
+
+  if (!dbs[dbname]) {
+    dbs[dbname] = { db: newDb() };
+  }
+
+  if (dbs[dbname].db._initialized) {
+    return PromiseA.resolve(dbs[dbname].db);
+  }
+
+  if (opts.init || ('init' === opts.type) || (opts.bits && opts.key)) {
+    dbs[dbname].initPromise = db.init(opts);
+  }
+
+  return dbs[dbname].initPromise || PromiseA.resolve(dbs[dbname].db);
 }
 
 module.exports.sanitize = sanitize;