如何将 dat-node 作为微服务运行？

Question

更新：添加了完整的服务器代码。请注意，静态内容的路由工作正常，只有与 Dat 相关的路由失败。另外，我正在运行节点10.8.0，没有转译器或任何东西，服务器运行micro -l tcp://0.0.0.0:$PORT

---

我正在尝试使用 Zeit micro 运行 dat-node。我有这个微服务

const { send } = require('micro')
const Dat = require('dat-node')
const handler = require('serve-handler')
const { router, get, post } = require('microrouter')

const static = async (request, response) => {
  await handler(request, response, {
  // static app folder
  public: 'static',
    // javascript header for es modules
    headers: {
      source: '**/*.mjs',
      headers: [{
        key: 'Content-Type',
        value: 'text/javascript'
      }]
    },
    // no directory listing
    directoryListing: false
  })
}

const createGame = (request, response) => {
  Dat('./game', (err, dat) => {
    if (err) throw err

    let progress = dat.importFiles({watch: true})

    progress.on('put', function (src, dest) {
      console.log('Importing ', src.name, ' into archive')
    })

    dat.joinNetwork()

    send(response, 200, { key: dat.key.toString('hex') })
  })
}

const joinGame = (request, response) => {

}

module.exports = router(
  post('/game', createGame),
  post('/game/:game', joinGame),
  get('/*', static)
)

我只想创建一个 dat 存档并返回公钥，但是当我调用 send 时出现此错误

(node:2054) UnhandledPromiseRejectionWarning: Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client
    at ServerResponse.setHeader (_http_outgoing.js:469:11)
    at send (/home/ubuntu/workspace/node_modules/micro/lib/index.js:72:8)
    at Dat (/home/ubuntu/workspace/index.js:35:5)
    at /home/ubuntu/workspace/node_modules/dat-node/index.js:112:9
    at apply (/home/ubuntu/workspace/node_modules/thunky/index.js:44:12)
    at process._tickCallback (internal/process/next_tick.js:63:19)(node:2054) UnhandledPromiseRejectionWarning: Unhandled promise rejection. This error originated either by throwing inside of an async function without a catch block, or by rejecting a promise which was not handled with .catch(). (rejection id: 1)(node:2054) [DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

所以，我不确定标头被发送到哪里，也许我只是以错误的方式处理 Dat 回调？不知道如何实施这项服务。

Answer 1

如果你导出函数，sn-p 就可以工作。使用micro whatever.js 运行并 curl 到 localhost:3000，它应该会返回密钥。

const { send } = require('micro')
const Dat = require('dat-node')

module.exports = (request, response) => {
  Dat('./game', async (err, dat) => {
    if (err) throw err

    let progress = dat.importFiles({watch: true})

    progress.on('put', function (src, dest) {
      console.log('Importing ', src.name, ' into archive')
    })

    dat.joinNetwork()

    send(response, 200, { key: dat.key.toString('hex') })
 })
}

Answer 2

问题似乎是micro 的使用，而不是dat-node 的任何问题。当你在 micro 中做异步工作时，你需要使用 Javascript (promises) 的 async/await 工具。

这里是固定代码：

const createGame = async (request, response) => {
  var key = await new Promise((resolve) => {
    Dat('./game', (err, dat) => {
      if (err) throw err

      let progress = dat.importFiles({watch: true})

      progress.on('put', function (src, dest) {
        console.log('Importing ', src.name, ' into archive')
      })

      dat.joinNetwork()
      resolve(dat.key.toString('hex'))
    })
  })
  console.log('sending')
  send(response, 200, { key })
}