var Utils = require("../../utils")
/**
Returns an object that treats SQLite's inabilities to do certain queries.
@class QueryInterface
@static
*/
var QueryInterface = module.exports = {
/**
A wrapper that fixes SQLite's inability to remove columns from existing tables.
It will create a backup of the table, drop the table afterwards and create a
new table with the same name but without the obsolete column.
@method removeColumn
@for QueryInterface
@param {String} tableName The name of the table.
@param {String} attributeName The name of the attribute that we want to remove.
@param {CustomEventEmitter} emitter The EventEmitter from outside.
@param {Function} queryAndEmit The function from outside that triggers some events to get triggered.
@since 1.6.0
*/
removeColumn: function(tableName, attributeName, emitter, queryAndEmit) {
this.describeTable(tableName).complete(function(err, fields) {
if (err) {
emitter.emit('error', err)
} else {
delete fields[attributeName]
var sql = this.QueryGenerator.removeColumnQuery(tableName, fields)
, subQueries = sql.split(';').filter(function(q) { return q !== '' })
QueryInterface.execMultiQuery.call(this, subQueries, 'removeColumn', emitter, queryAndEmit)
}
}.bind(this))
},
/**
A wrapper that fixes SQLite's inability to change columns from existing tables.
It will create a backup of the table, drop the table afterwards and create a
new table with the same name but with a modified version of the respective column.
@method changeColumn
@for QueryInterface
@param {String} tableName The name of the table.
@param {Object} attributes An object with the attribute's name as key and it's options as value object.
@param {CustomEventEmitter} emitter The EventEmitter from outside.
@param {Function} queryAndEmit The function from outside that triggers some events to get triggered.
@since 1.6.0
*/
changeColumn: function(tableName, attributes, emitter, queryAndEmit) {
var attributeName = Utils._.keys(attributes)[0]
this.describeTable(tableName).complete(function(err, fields) {
if (err) {
emitter.emit('error', err)
} else {
fields[attributeName] = attributes[attributeName]
var sql = this.QueryGenerator.removeColumnQuery(tableName, fields)
, subQueries = sql.split(';').filter(function(q) { return q !== '' })
QueryInterface.execMultiQuery.call(this, subQueries, 'changeColumn', emitter, queryAndEmit)
}
}.bind(this))
},
/**
A wrapper that fixes SQLite's inability to rename columns from existing tables.
It will create a backup of the table, drop the table afterwards and create a
new table with the same name but with a renamed version of the respective column.
@method renameColumn
@for QueryInterface
@param {String} tableName The name of the table.
@param {String} attrNameBefore The name of the attribute before it was renamed.
@param {String} attrNameAfter The name of the attribute after it was renamed.
@param {CustomEventEmitter} emitter The EventEmitter from outside.
@param {Function} queryAndEmit The function from outside that triggers some events to get triggered.
@since 1.6.0
*/
renameColumn: function(tableName, attrNameBefore, attrNameAfter, emitter, queryAndEmit) {
this.describeTable(tableName).complete(function(err, fields) {
if (err) {
emitter.emit('error', err)
} else {
fields[attrNameAfter] = Utils._.clone(fields[attrNameBefore])
delete fields[attrNameBefore]
var sql = this.QueryGenerator.renameColumnQuery(tableName, attrNameBefore, attrNameAfter, fields)
, subQueries = sql.split(';').filter(function(q) { return q !== '' })
QueryInterface.execMultiQuery.call(this, subQueries, 'renameColumn', emitter, queryAndEmit)
}
}.bind(this))
},
execMultiQuery: function(queries, methodName, emitter, queryAndEmit) {
var chainer = new Utils.QueryChainer()
queries.splice(0, queries.length - 1).forEach(function(query) {
chainer.add(this.sequelize, 'query', [query + ";", null, { raw: true }])
}.bind(this))
chainer
.runSerially()
.complete(function(err) {
if (err) {
emitter.emit(methodName, err)
emitter.emit('error', err)
} else {
queryAndEmit.call(this, queries.splice(queries.length - 1)[0], methodName, {}, emitter)
}
}.bind(this))
}
}