feat: add monitor module (#28)

* feat: add monitor module

* feat: add monitor export

* fix: lint errors

* fix: fix lint err && add exception case

Co-authored-by: yugasun <yuga_sun@163.com>

Author: wescai

src/index.js

@@ -9,6 +9,7 @@ const Scf = require('./baas/scf')
 const Tag = require('./baas/tag')
 const Postgresql = require('./baas/postgresql')
 const Vpc = require('./baas/vpc')
+const monitor = require('./monitor')
 
 module.exports = {
   Apigw,
@@ -21,5 +22,6 @@ module.exports = {
   Scf,
   Tag,
   Postgresql,
-  Vpc
+  Vpc,
+  monitor
 }

src/monitor/agent.js

@@ -0,0 +1,8 @@
+const { EventEmitter } = require('events')
+const util = require('util')
+
+function Agent() {}
+
+util.inherits(Agent, EventEmitter)
+
+module.exports = Agent

src/monitor/constants.js

@@ -0,0 +1,21 @@
+/**
+ * Enumeration of module instrumentation types.
+ *
+ * @private
+ * @readonly
+ * @enum {string}
+ */
+const MODULE_TYPE = {
+  /** Web server framework module, such as Express or Koa. */
+  WEB_FRAMEWORK: 'web-framework',
+  PROXY: 'proxy'
+}
+
+exports.MODULE_TYPE = MODULE_TYPE
+
+/**
+ * 请求开始时间存储key值(context内)
+ */
+const REUQEST_START = '__request_start__'
+
+exports.REUQEST_START_KEY = REUQEST_START

src/monitor/index.js

@@ -0,0 +1,12 @@
+const shimmer = require('./shimmer')
+const Agent = require('./agent')
+
+function initialize() {
+  const agent = new Agent()
+  // 封装 module的_load方法，在load时针对基础组件附加探针
+  shimmer.patchModule()
+  // 初始化一系列基础组件
+  shimmer.bootstrapInstrumentation(agent)
+}
+
+initialize()

src/monitor/instrumentation/express.js

@@ -0,0 +1,65 @@
+const utils = require('../utils')
+
+/**
+ * Express middleware generates traces where middleware are considered siblings
+ * (ended on 'next' invocation) and not nested. Middlware are nested below the
+ * routers they are mounted to.
+ */
+
+function wrapRouteMethods(route) {
+  const methods = ['all', 'delete', 'get', 'head', 'opts', 'post', 'put', 'patch']
+  utils.wrapMethod(route, methods, function(fn) {
+    return fn
+  })
+}
+
+module.exports = function initialize(agent, express) {
+  if (!express || !express.Router) {
+    return false
+  }
+
+  // wrapExpress4(express)
+  utils.wrapMethod(express.Router, 'route', function wrapRoute(fn) {
+    if (!utils.isFunction(fn)) {
+      return fn
+    }
+
+    return function wrappedRoute() {
+      const sourceRoute = fn.apply(this, arguments)
+      // Express should create a new route and layer every time Router#route is
+      // called, but just to be on the safe side, make sure we haven't wrapped
+      // this already.
+      if (!utils.isWrapped(sourceRoute, 'get')) {
+        wrapRouteMethods(sourceRoute)
+
+        const layer = this.stack[this.stack.length - 1]
+        utils.wrapMethod(layer, 'handle', function(func) {
+          const { route } = layer
+          const { path } = route
+          return function(request, response) {
+            function finish() {
+              response.removeListener('finish', finish)
+              request.removeListener('aborted', finish)
+              // 状态码
+              if (response.statusCode != null) {
+                const responseCode = String(response.statusCode)
+                if (/^\d+$/.test(responseCode)) {
+                  const context = request.headers['x-apigateway-context']
+                  agent.emit('responseFinish', context, request.method, path, responseCode)
+                }
+              }
+            }
+
+            // response结束时上报状态码和耗时
+            response.once('finish', finish)
+            request.once('aborted', finish)
+
+            const handle = func.apply(this, arguments)
+            return handle
+          }
+        })
+      }
+      return sourceRoute
+    }
+  })
+}

src/monitor/instrumentation/tencent-serverless-http.js

@@ -0,0 +1,28 @@
+const utils = require('../utils')
+const { REUQEST_START_KEY } = require('../constants')
+const report = require('../report')
+
+module.exports = function initialize(agent, httpProxy) {
+  utils.wrapMethod(httpProxy, 'proxy', function wrapRoute(fn) {
+    return function(server, event, context) {
+      context[REUQEST_START_KEY] = Date.now()
+      const proxy = fn.apply(this, arguments)
+      return new Promise(function(resolve) {
+        agent.on('responseFinish', function(ctx, method, path, responseCode) {
+          if (ctx) {
+            report.reportHttp(ctx, method, path, responseCode).then(
+              function() {
+                resolve(proxy)
+              },
+              function() {
+                resolve(proxy)
+              }
+            )
+          } else {
+            resolve(proxy)
+          }
+        })
+      })
+    }
+  })
+}

src/monitor/instrumentations.js

@@ -0,0 +1,8 @@
+const { MODULE_TYPE } = require('./constants')
+
+module.exports = function instrumentations() {
+  return {
+    express: { type: MODULE_TYPE.WEB_FRAMEWORK },
+    'tencent-serverless-http': { type: MODULE_TYPE.PROXY }
+  }
+}

src/monitor/logger.js

@@ -0,0 +1 @@
+module.exports = console

src/monitor/report.js

@@ -0,0 +1,84 @@
+const { Capi } = require('@tencent-sdk/capi')
+const logger = require('./logger')
+const { REUQEST_START_KEY } = require('./constants')
+
+// 字符串转16进制
+function str2hex(str) {
+  if (str === '') {
+    return ''
+  }
+  const arr = []
+  for (let i = 0; i < str.length; i++) {
+    arr.push(str.charCodeAt(i).toString(16))
+  }
+  return arr.join('')
+}
+
+exports.reportHttp = async function(context, method, path, statusCode) {
+  try {
+    context = JSON.parse(decodeURIComponent(context))
+    path = str2hex(path)
+    const ServiceType = 'monitor'
+    const {
+      tencentcloud_region,
+      function_name: FunctionName,
+      function_version: Version = '$latest',
+      namespace: Namespace = 'default'
+    } = context
+    const environment = JSON.parse(context.environment || '{}')
+    const {
+      TENCENTCLOUD_SECRETID: SecretId,
+      TENCENTCLOUD_SECRETKEY: SecretKey,
+      TENCENTCLOUD_SESSIONTOKEN: Token,
+      TENCENTCLOUD_REGION: envTencentRegion,
+      REGION: envRegion
+    } = environment
+    const Region = tencentcloud_region || envTencentRegion || envRegion || 'ap-guangzhou'
+    if (!SecretId || !SecretKey) {
+      logger.warn('No SecretId or SecretKey in environment parameters.')
+      return
+    }
+    const client = new Capi({
+      Region,
+      SecretId,
+      SecretKey,
+      Token,
+      ServiceType
+    })
+    const commonParams = {
+      Version: '2018-07-24',
+      AnnounceInstance: `${Namespace}|${FunctionName}|${Version}`
+    }
+    const debugOptions = {
+      debug: false,
+      host: 'monitor.tencentcloudapi.com'
+    }
+
+    const latency = Date.now() - context[REUQEST_START_KEY]
+    const keyPrefix = `${method}_${path}`
+    const Metrics = [
+      { MetricName: 'request', Value: 1 },
+      { MetricName: keyPrefix, Value: 1 },
+      { MetricName: 'latency', Value: latency },
+      { MetricName: keyPrefix + '_latency', Value: latency },
+      { MetricName: keyPrefix + '_' + statusCode, Value: 1 }
+    ]
+    if (statusCode.startsWith('4')) {
+      Metrics.push({ MetricName: '4xx', Value: 1 })
+      Metrics.push({ MetricName: 'error', Value: 1 })
+    } else if (statusCode.startsWith('5')) {
+      Metrics.push({ MetricName: '5xx', Value: 1 })
+      Metrics.push({ MetricName: 'error', Value: 1 })
+    }
+
+    return client.request(
+      {
+        Action: 'PutMonitorData',
+        Metrics,
+        ...commonParams
+      },
+      debugOptions,
+      true
+    )
+  } catch (e) {}
+}