fix(mdc): pass context through async/await call stack

closes #2

Author: antongolub

flow-typed/cls-hooked.js

@@ -0,0 +1,15 @@
+declare module 'cls-hooked' {
+  declare type IAny = any
+  
+  declare export type INamespace = {
+    run: (fn: Function) => void,
+    set: (name: string, data: IAny) => void,
+    get: (name: string) => IAny,
+    bindEmitter: (fn: Function) => void
+  }
+  
+  declare module.exports: {
+    createNamespace: (name: string) => INamespace,
+    getNamespace: (name: string) => INamespace
+  }
+}

package.json

@@ -31,35 +31,35 @@
   "author": "Anton Golub <a.golub@qiwi.com>",
   "license": "MIT",
   "devDependencies": {
-    "@babel/cli": "^7.1.2",
-    "@babel/core": "^7.1.2",
+    "@babel/cli": "^7.1.5",
+    "@babel/core": "^7.1.5",
     "@babel/plugin-proposal-class-properties": "^7.1.0",
     "@babel/plugin-proposal-object-rest-spread": "^7.0.0",
     "@babel/plugin-transform-modules-commonjs": "^7.1.0",
     "@babel/plugin-transform-runtime": "^7.1.0",
-    "@babel/preset-env": "^7.1.0",
+    "@babel/preset-env": "^7.1.5",
     "@babel/preset-flow": "^7.0.0",
     "@babel/register": "^7.0.0",
     "@semantic-release/changelog": "^3.0.1",
     "@semantic-release/commit-analyzer": "^6.1.0",
     "@semantic-release/git": "7.0.5",
     "@semantic-release/github": "5.2.1",
-    "@semantic-release/npm": "5.0.5",
-    "@semantic-release/release-notes-generator": "7.1.3",
+    "@semantic-release/npm": "5.0.6",
+    "@semantic-release/release-notes-generator": "7.1.4",
     "babel-core": "^7.0.0-bridge.0",
     "babel-eslint": "^10.0.1",
     "babel-jest": "^23.6.0",
     "coveralls": "^3.0.2",
     "docma": "^2.1.0",
     "eslint": "^5.8.0",
     "eslint-plugin-flowtype": "^3.2.0",
-    "flow-bin": "^0.85.0",
+    "flow-bin": "^0.86.0",
     "flow-coverage-report": "^0.6.0",
     "flow-remove-types": "^1.2.3",
     "flow-typed": "^2.5.1",
     "jest": "^23.6.0",
     "lerna": "^3.4.3",
-    "semantic-release": "15.10.7",
+    "semantic-release": "15.10.8",
     "semantic-release-monorepo": "6.1.1",
     "semantic-release-monorepo-hooks": "2.6.2",
     "semantic-release-plugin-decorators": "^2.0.0",

packages/mware-mdc/package.json

@@ -28,7 +28,7 @@
   },
   "homepage": "https://github.com/qiwi/mware#readme",
   "dependencies": {
-    "continuation-local-storage": "^3.2.1"
+    "cls-hooked":"^4.2.2"
   },
   "devDependencies": {
     "lodash": "^4.17.11",

packages/mware-mdc/src/Mdc.js

@@ -1,8 +1,8 @@
 // @flow
 
 import crypto from 'crypto'
-import {createNamespace, getNamespace} from 'continuation-local-storage'
-import type {INamespace} from 'continuation-local-storage'
+import {createNamespace, getNamespace} from 'cls-hooked'
+import type {INamespace} from 'cls-hooked'
 import type {
   IAny,
   IRequest,

packages/mware-mdc/test/index.js

@@ -2,7 +2,6 @@ import factory from '../src'
 import reqresnext from 'reqresnext'
 
 describe('mware-mdc', () => {
-
   beforeEach(() => {
     jest.resetAllMocks()
   })
@@ -23,16 +22,26 @@ describe('mware-mdc', () => {
     expect(next).toHaveBeenCalled()
   })
 
-  it('attaches req.trace field', () => {
+  it('attaches req.trace field and passes through inner async context', done => {
     const mware = factory({})
-    const {req, res} = reqresnext(null, null)
-
-    mware(req, res, () => {
+    const {req, res} = reqresnext()
+    const delayed = (req) => new Promise(resolve => setTimeout(() => resolve(req.trace), 200))
+    const inner = () => {
       expect(req.trace).toMatchObject({
         trace_id: expect.stringMatching(/^[0-9a-f]{16}$/),
         span_id: expect.stringMatching(/^[0-9a-f]{16}$/),
       })
-    })
+
+      delayed(req)
+        .then(trace => {
+          expect(trace).toMatchObject({
+            trace_id: expect.stringMatching(/^[0-9a-f]{16}$/),
+            span_id: expect.stringMatching(/^[0-9a-f]{16}$/),
+          })
+        })
+        .then(() => done())
+    }
+    mware(req, res, inner)
 
     expect(req.trace).toBeUndefined()
   })

packages/mware/README.md

@@ -10,6 +10,8 @@ npm i @qiwi/mware
 ### Middlewares
 * [mware-mdc](../mware-mdc/README.md)
 * [mware-logger](../mware-logger/README.md)
+* [mware-crumbs](../mware-crumbs/README.md)
+* [mware-cors](../mware-cors/README.md)
 
 ### Usage
 
@@ -22,4 +24,23 @@ const app = express()
 app.use(cors())
 app.use(mdc())
 app.listen(...)
+```
+
+### Utils
+```
+import express from 'express'
+import {util} from '@qiwi/mware'
+
+const {asyncMiddleware} = util
+...
+
+app.get('/', asyncMiddleware(async (req, res, next) => {
+    ...
+    throw new Error('Something went wrong')
+}))
+
+app.use((error, req, res, next) => {
+    error // Error('Something went wrong')
+})
+
 ```