rss-feeder-mobilizon/node_modules/pg/lib/native/client.js

295 lines
7.3 KiB
JavaScript

'use strict'
// eslint-disable-next-line
var Native = require('pg-native')
var TypeOverrides = require('../type-overrides')
var pkg = require('../../package.json')
var EventEmitter = require('events').EventEmitter
var util = require('util')
var ConnectionParameters = require('../connection-parameters')
var NativeQuery = require('./query')
var Client = (module.exports = function (config) {
EventEmitter.call(this)
config = config || {}
this._Promise = config.Promise || global.Promise
this._types = new TypeOverrides(config.types)
this.native = new Native({
types: this._types,
})
this._queryQueue = []
this._ending = false
this._connecting = false
this._connected = false
this._queryable = true
// keep these on the object for legacy reasons
// for the time being. TODO: deprecate all this jazz
var cp = (this.connectionParameters = new ConnectionParameters(config))
this.user = cp.user
// "hiding" the password so it doesn't show up in stack traces
// or if the client is console.logged
Object.defineProperty(this, 'password', {
configurable: true,
enumerable: false,
writable: true,
value: cp.password,
})
this.database = cp.database
this.host = cp.host
this.port = cp.port
// a hash to hold named queries
this.namedQueries = {}
})
Client.Query = NativeQuery
util.inherits(Client, EventEmitter)
Client.prototype._errorAllQueries = function (err) {
const enqueueError = (query) => {
process.nextTick(() => {
query.native = this.native
query.handleError(err)
})
}
if (this._hasActiveQuery()) {
enqueueError(this._activeQuery)
this._activeQuery = null
}
this._queryQueue.forEach(enqueueError)
this._queryQueue.length = 0
}
// connect to the backend
// pass an optional callback to be called once connected
// or with an error if there was a connection error
Client.prototype._connect = function (cb) {
var self = this
if (this._connecting) {
process.nextTick(() => cb(new Error('Client has already been connected. You cannot reuse a client.')))
return
}
this._connecting = true
this.connectionParameters.getLibpqConnectionString(function (err, conString) {
if (err) return cb(err)
self.native.connect(conString, function (err) {
if (err) {
self.native.end()
return cb(err)
}
// set internal states to connected
self._connected = true
// handle connection errors from the native layer
self.native.on('error', function (err) {
self._queryable = false
self._errorAllQueries(err)
self.emit('error', err)
})
self.native.on('notification', function (msg) {
self.emit('notification', {
channel: msg.relname,
payload: msg.extra,
})
})
// signal we are connected now
self.emit('connect')
self._pulseQueryQueue(true)
cb()
})
})
}
Client.prototype.connect = function (callback) {
if (callback) {
this._connect(callback)
return
}
return new this._Promise((resolve, reject) => {
this._connect((error) => {
if (error) {
reject(error)
} else {
resolve()
}
})
})
}
// send a query to the server
// this method is highly overloaded to take
// 1) string query, optional array of parameters, optional function callback
// 2) object query with {
// string query
// optional array values,
// optional function callback instead of as a separate parameter
// optional string name to name & cache the query plan
// optional string rowMode = 'array' for an array of results
// }
Client.prototype.query = function (config, values, callback) {
var query
var result
var readTimeout
var readTimeoutTimer
var queryCallback
if (config === null || config === undefined) {
throw new TypeError('Client was passed a null or undefined query')
} else if (typeof config.submit === 'function') {
readTimeout = config.query_timeout || this.connectionParameters.query_timeout
result = query = config
// accept query(new Query(...), (err, res) => { }) style
if (typeof values === 'function') {
config.callback = values
}
} else {
readTimeout = this.connectionParameters.query_timeout
query = new NativeQuery(config, values, callback)
if (!query.callback) {
let resolveOut, rejectOut
result = new this._Promise((resolve, reject) => {
resolveOut = resolve
rejectOut = reject
})
query.callback = (err, res) => (err ? rejectOut(err) : resolveOut(res))
}
}
if (readTimeout) {
queryCallback = query.callback
readTimeoutTimer = setTimeout(() => {
var error = new Error('Query read timeout')
process.nextTick(() => {
query.handleError(error, this.connection)
})
queryCallback(error)
// we already returned an error,
// just do nothing if query completes
query.callback = () => {}
// Remove from queue
var index = this._queryQueue.indexOf(query)
if (index > -1) {
this._queryQueue.splice(index, 1)
}
this._pulseQueryQueue()
}, readTimeout)
query.callback = (err, res) => {
clearTimeout(readTimeoutTimer)
queryCallback(err, res)
}
}
if (!this._queryable) {
query.native = this.native
process.nextTick(() => {
query.handleError(new Error('Client has encountered a connection error and is not queryable'))
})
return result
}
if (this._ending) {
query.native = this.native
process.nextTick(() => {
query.handleError(new Error('Client was closed and is not queryable'))
})
return result
}
this._queryQueue.push(query)
this._pulseQueryQueue()
return result
}
// disconnect from the backend server
Client.prototype.end = function (cb) {
var self = this
this._ending = true
if (!this._connected) {
this.once('connect', this.end.bind(this, cb))
}
var result
if (!cb) {
result = new this._Promise(function (resolve, reject) {
cb = (err) => (err ? reject(err) : resolve())
})
}
this.native.end(function () {
self._errorAllQueries(new Error('Connection terminated'))
process.nextTick(() => {
self.emit('end')
if (cb) cb()
})
})
return result
}
Client.prototype._hasActiveQuery = function () {
return this._activeQuery && this._activeQuery.state !== 'error' && this._activeQuery.state !== 'end'
}
Client.prototype._pulseQueryQueue = function (initialConnection) {
if (!this._connected) {
return
}
if (this._hasActiveQuery()) {
return
}
var query = this._queryQueue.shift()
if (!query) {
if (!initialConnection) {
this.emit('drain')
}
return
}
this._activeQuery = query
query.submit(this)
var self = this
query.once('_done', function () {
self._pulseQueryQueue()
})
}
// attempt to cancel an in-progress query
Client.prototype.cancel = function (query) {
if (this._activeQuery === query) {
this.native.cancel(function () {})
} else if (this._queryQueue.indexOf(query) !== -1) {
this._queryQueue.splice(this._queryQueue.indexOf(query), 1)
}
}
Client.prototype.setTypeParser = function (oid, format, parseFn) {
return this._types.setTypeParser(oid, format, parseFn)
}
Client.prototype.getTypeParser = function (oid, format) {
return this._types.getTypeParser(oid, format)
}