Commit iniziale

node_modules/mssql/lib/global-connection.js

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+'use strict'
+
+const shared = require('./shared')
+
+let globalConnection = null
+const globalConnectionHandlers = {}
+
+/**
+ * Open global connection pool.
+ *
+ * @param {Object|String} config Connection configuration object or connection string.
+ * @param {basicCallback} [callback] A callback which is called after connection has established, or an error has occurred. If omited, method returns Promise.
+ * @return {Promise.<ConnectionPool>}
+ */
+
+function connect (config, callback) {
+  if (!globalConnection) {
+    globalConnection = new shared.driver.ConnectionPool(config)
+
+    for (const event in globalConnectionHandlers) {
+      for (let i = 0, l = globalConnectionHandlers[event].length; i < l; i++) {
+        globalConnection.on(event, globalConnectionHandlers[event][i])
+      }
+    }
+
+    const ogClose = globalConnection.close
+
+    const globalClose = function (callback) {
+      // remove event handlers from the global connection
+      for (const event in globalConnectionHandlers) {
+        for (let i = 0, l = globalConnectionHandlers[event].length; i < l; i++) {
+          this.removeListener(event, globalConnectionHandlers[event][i])
+        }
+      }
+
+      // attach error handler to prevent process crash in case of error
+      this.on('error', err => {
+        if (globalConnectionHandlers.error) {
+          for (let i = 0, l = globalConnectionHandlers.error.length; i < l; i++) {
+            globalConnectionHandlers.error[i].call(this, err)
+          }
+        }
+      })
+
+      globalConnection = null
+      return ogClose.call(this, callback)
+    }
+
+    globalConnection.close = globalClose.bind(globalConnection)
+  }
+  if (typeof callback === 'function') {
+    return globalConnection.connect((err, connection) => {
+      if (err) {
+        globalConnection = null
+      }
+      callback(err, connection)
+    })
+  }
+  return globalConnection.connect().catch((err) => {
+    globalConnection = null
+    return shared.Promise.reject(err)
+  })
+}
+
+/**
+ * Close all active connections in the global pool.
+ *
+ * @param {basicCallback} [callback] A callback which is called after connection has closed, or an error has occurred. If omited, method returns Promise.
+ * @return {ConnectionPool|Promise}
+ */
+
+function close (callback) {
+  if (globalConnection) {
+    const gc = globalConnection
+    globalConnection = null
+    return gc.close(callback)
+  }
+
+  if (typeof callback === 'function') {
+    setImmediate(callback)
+    return null
+  }
+
+  return new shared.Promise((resolve) => {
+    resolve(globalConnection)
+  })
+}
+
+/**
+ * Attach event handler to global connection pool.
+ *
+ * @param {String} event Event name.
+ * @param {Function} handler Event handler.
+ * @return {ConnectionPool}
+ */
+
+function on (event, handler) {
+  if (!globalConnectionHandlers[event]) globalConnectionHandlers[event] = []
+  globalConnectionHandlers[event].push(handler)
+
+  if (globalConnection) globalConnection.on(event, handler)
+  return globalConnection
+}
+
+/**
+ * Detach event handler from global connection.
+ *
+ * @param {String} event Event name.
+ * @param {Function} handler Event handler.
+ * @return {ConnectionPool}
+ */
+
+function removeListener (event, handler) {
+  if (!globalConnectionHandlers[event]) return globalConnection
+  const index = globalConnectionHandlers[event].indexOf(handler)
+  if (index === -1) return globalConnection
+  globalConnectionHandlers[event].splice(index, 1)
+  if (globalConnectionHandlers[event].length === 0) globalConnectionHandlers[event] = undefined
+
+  if (globalConnection) globalConnection.removeListener(event, handler)
+  return globalConnection
+}
+
+/**
+ * Creates a new query using global connection from a tagged template string.
+ *
+ * @variation 1
+ * @param {Array|String} strings Array of string literals or sql command.
+ * @param {...*} keys Values.
+ * @return {Request}
+ */
+
+/**
+ * Execute the SQL command.
+ *
+ * @variation 2
+ * @param {String} command T-SQL command to be executed.
+ * @param {Request~requestCallback} [callback] A callback which is called after execution has completed, or an error has occurred. If omited, method returns Promise.
+ * @return {Request|Promise}
+ */
+
+function query () {
+  if (typeof arguments[0] === 'string') { return new shared.driver.Request().query(arguments[0], arguments[1]) }
+
+  const values = Array.prototype.slice.call(arguments)
+  const strings = values.shift()
+
+  return new shared.driver.Request()._template(strings, values, 'query')
+}
+
+/**
+ * Creates a new batch using global connection from a tagged template string.
+ *
+ * @variation 1
+ * @param {Array} strings Array of string literals.
+ * @param {...*} keys Values.
+ * @return {Request}
+ */
+
+/**
+ * Execute the SQL command.
+ *
+ * @variation 2
+ * @param {String} command T-SQL command to be executed.
+ * @param {Request~requestCallback} [callback] A callback which is called after execution has completed, or an error has occurred. If omited, method returns Promise.
+ * @return {Request|Promise}
+ */
+
+function batch () {
+  if (typeof arguments[0] === 'string') { return new shared.driver.Request().batch(arguments[0], arguments[1]) }
+
+  const values = Array.prototype.slice.call(arguments)
+  const strings = values.shift()
+
+  return new shared.driver.Request()._template(strings, values, 'batch')
+}
+
+module.exports = {
+  batch,
+  close,
+  connect,
+  off: removeListener,
+  on,
+  query,
+  removeListener
+}
+
+Object.defineProperty(module.exports, 'pool', {
+  get: () => {
+    return globalConnection
+  },
+  set: () => {}
+})