clients/server/sqlite3

SQLite3

All of the "when.js" promise components needed in this module.

var when = require('when'); var nodefn = require('when/node/function');

Other dependencies, including the sqlite3 library, which needs to be added as a dependency to the project using this database.

var _ = require('underscore'); var sqlite3 = require('sqlite3');

All other local project modules needed in this scope.

var SQLite3Base = require('../base/sqlite3'); var ServerBase = require('./base').ServerBase; var Builder = require('../../lib/builder').Builder; var Transaction = require('../../lib/transaction').Transaction; var SchemaInterface = require('../../lib/schemainterface').SchemaInterface; var Helpers = require('../../lib/helpers').Helpers;

Constructor for the SQLite3Client.

var SQLite3Client = exports.Client = ServerBase.extend({ dialect: 'sqlite3',

Runs the query on the specified connection, providing the bindings and any other necessary prep work.

runQuery: function(connection, sql, bindings, builder) { if (!connection) throw new Error('No database connection exists for the query'); if (sql === '__rename_column__') { return this.ddl(connection, sql, bindings, builder); } var method = (builder.type === 'insert' || builder.type === 'update' || builder.type === 'delete') ? 'run' : 'all';

Call the querystring and then release the client

var dfd = when.defer(); connection[method](sql, bindings, function(err, resp) { if (err) return dfd.reject(err);

We need the context here, because it has the "this.lastID" or "this.changes"

return dfd.resolve([resp, this]); }); return dfd.promise; }, poolDefaults: { max: 1, min: 1, destroy: function(client) { client.close(); } }, ddl: function(connection, sql, bindings, builder) { var client = this; return nodefn.call(connection.run.bind(connection), 'begin transaction;').then(function() { var transaction = new Transaction({client: client}); var containerObj = transaction.getContainerObject(connection); return transaction.initiateDeferred(function(trx) { client.alterSchema.call(client, builder, trx); })(containerObj); }); }, getRawConnection: function() { var dfd = when.defer(); var db = new sqlite3.Database(this.connectionSettings.filename, function(err) { if (err) return dfd.reject(err); dfd.resolve(db); }); return dfd.promise; },

Used to explicitly close a connection, called internally by the pool when a connection times out or the pool is shutdown.

destroyRawConnection: function(connection) { connection.close(); },

Begins a transaction statement on the instance, resolving with the connection of the current transaction.

startTransaction: function(connection) { return this.getConnection().tap(function(connection) { return nodefn.call(connection.run.bind(connection), 'begin transaction;', []); }); },

Finishes the transaction statement on the instance.

finishTransaction: function(type, transaction, msg) { var client = this; var dfd = transaction.dfd; nodefn.call(transaction.connection.run.bind(transaction.connection), type + ';', []).then(function(resp) { if (type === 'commit') dfd.resolve(msg || resp); if (type === 'rollback') dfd.reject(msg || resp); }, function (err) { dfd.reject(err); }).ensure(function() { return client.releaseConnection(transaction.connection).tap(function() { transaction.connection = null; }); }); },

This needs to be refactored... badly.

alterSchema: function(builder, trx) { var connection = trx.connection; var currentCol, command; return when.all([ nodefn.call(connection.all.bind(connection), 'PRAGMA table_info(' + builder.table + ')', []), nodefn.call(connection.all.bind(connection), 'SELECT name, sql FROM sqlite_master WHERE type="table" AND name="' + builder.table + '"', []) ]) .tap(function(resp) { var pragma = resp[0]; var sql = resp[1][0]; command = builder.commands[builder.currentIndex]; if (!(currentCol = _.findWhere(pragma, {name: command.from}))) { throw new Error('The column ' + command.from + ' is not in the current table'); } return nodefn.call(connection.all.bind(connection), 'ALTER TABLE ' + sql.name + ' RENAME TO __migrate__' + sql.name); }).spread(function(pragma, sql) { sql = sql[0]; var currentColumn = '"' + command.from + '" ' + currentCol.type; var newColumn = '"' + command.to + '" ' + currentCol.type; if (sql.sql.indexOf(currentColumn) === -1) { return trx.reject('Unable to find the column to change'); } return when.all([ nodefn.call(connection.all.bind(connection), sql.sql.replace(currentColumn, newColumn)), nodefn.call(connection.all.bind(connection), 'SELECT * FROM "__migrate__' + sql.name + '"'), ]); }).spread(function(createTable, selected) { var qb = new Builder(builder.knex).transacting(trx); qb.table = builder.table; return when.all([ qb.insert(_.map(selected, function(row) { row[command.to] = row[command.from]; return _.omit(row, command.from); })), nodefn.call(connection.all.bind(connection), 'DROP TABLE "__migrate__' + builder.table + '"') ]); }).then(trx.commit, trx.rollback); } }); exports.grammar = _.defaults({ handleResponse: function(builder, resp) { var ctx = resp[1]; resp = resp[0]; if (builder.type === 'select') { resp = Helpers.skim(resp); } else if (builder.type === 'insert') { resp = [ctx.lastID]; } else if (builder.type === 'delete' || builder.type === 'update') { resp = ctx.changes; } return resp; } }, SQLite3Base.grammar); exports.schemaGrammar = _.defaults({ handleResponse: function(builder, resp) {

This is an array, so we'll assume that the relevant info is on the first statement...

resp = resp[0]; var ctx = resp[1]; resp = resp[0]; if (builder.type === 'tableExists') { return resp.length > 0; } else if (builder.type === 'columnExists') { return _.findWhere(resp, {name: builder.bindings[1]}) != null; } return resp; } }, SQLite3Base.schemaGrammar);