Question

所以，我在ES6 / node中编写服务器端应用程序。以下是违规代码。我知道这不是ES6，但应用程序的其他部分是（理想情况下，我正在使用ES6的导入 - 我只是回归要求，因为我想测试原始代码节点本身无需转换。

var os = require("os");
var hostname = os.hostname();
console.log(hostname);

所以，如果我有一个名为test.js的JavaScript文件，其中包含该代码...然后我在节点处抛出它，在控制台上打印出正确的主机名。

但如果我通过babel运行它，当我运行它时，我什么也得不到。完全没有输出。

有趣的是，如果我将这一行添加到代码中：

的console.log（OS）

然后原始的JS给了我这个输出：

{ hostname: [Function: getHostname],
  uptime: [Function: getUptime],
  freemem: [Function: getFreeMem],
  totalmem: [Function: getTotalMem],
  cpus: [Function: getCPUs],
  type: [Function: getOSType],
  release: [Function: getOSRelease],
  networkInterfaces: [Function: getInterfaceAddresses],
  homedir: [Function: getHomeDirectory],
  userInfo: [Function: getUserInfo],
  loadavg: [Function: loadavg],
  constants:
   { UV_UDP_REUSEADDR: 4,
     errno:
      { E2BIG: 7,
        EACCES: 13,
        EADDRINUSE: 98,
        EADDRNOTAVAIL: 99,
        EAFNOSUPPORT: 97,
        EAGAIN: 11,
        EALREADY: 114,
        EBADF: 9,
        EBADMSG: 74,
        EBUSY: 16,
        ECANCELED: 125,
        ECHILD: 10,
        ECONNABORTED: 103,
        ECONNREFUSED: 111,
        ECONNRESET: 104,
        EDEADLK: 35,
        EDESTADDRREQ: 89,
        EDOM: 33,
        EDQUOT: 122,
        EEXIST: 17,
        EFAULT: 14,
        EFBIG: 27,
        EHOSTUNREACH: 113,
        EIDRM: 43,
        EILSEQ: 84,
        EINPROGRESS: 115,
        EINTR: 4,
        EINVAL: 22,
        EIO: 5,
        EISCONN: 106,
        EISDIR: 21,
        ELOOP: 40,
        EMFILE: 24,
        EMLINK: 31,
        EMSGSIZE: 90,
        EMULTIHOP: 72,
        ENAMETOOLONG: 36,
        ENETDOWN: 100,
        ENETRESET: 102,
        ENETUNREACH: 101,
        ENFILE: 23,
        ENOBUFS: 105,
        ENODATA: 61,
        ENODEV: 19,
        ENOENT: 2,
        ENOEXEC: 8,
        ENOLCK: 37,
        ENOLINK: 67,
        ENOMEM: 12,
        ENOMSG: 42,
        ENOPROTOOPT: 92,
        ENOSPC: 28,
        ENOSR: 63,
        ENOSTR: 60,
        ENOSYS: 38,
        ENOTCONN: 107,
        ENOTDIR: 20,
        ENOTEMPTY: 39,
        ENOTSOCK: 88,
        ENOTSUP: 95,
        ENOTTY: 25,
        ENXIO: 6,
        EOPNOTSUPP: 95,
        EOVERFLOW: 75,
        EPERM: 1,
        EPIPE: 32,
        EPROTO: 71,
        EPROTONOSUPPORT: 93,
        EPROTOTYPE: 91,
        ERANGE: 34,
        EROFS: 30,
        ESPIPE: 29,
        ESRCH: 3,
        ESTALE: 116,
        ETIME: 62,
        ETIMEDOUT: 110,
        ETXTBSY: 26,
        EWOULDBLOCK: 11,
        EXDEV: 18 },
     signals:
      { SIGHUP: 1,
        SIGINT: 2,
        SIGQUIT: 3,
        SIGILL: 4,
        SIGTRAP: 5,
        SIGABRT: 6,
        SIGIOT: 6,
        SIGBUS: 7,
        SIGFPE: 8,
        SIGKILL: 9,
        SIGUSR1: 10,
        SIGSEGV: 11,
        SIGUSR2: 12,
        SIGPIPE: 13,
        SIGALRM: 14,
        SIGTERM: 15,
        SIGCHLD: 17,
        SIGSTKFLT: 16,
        SIGCONT: 18,
        SIGSTOP: 19,
        SIGTSTP: 20,
        SIGTTIN: 21,
        SIGTTOU: 22,
        SIGURG: 23,
        SIGXCPU: 24,
        SIGXFSZ: 25,
        SIGVTALRM: 26,
        SIGPROF: 27,
        SIGWINCH: 28,
        SIGIO: 29,
        SIGPOLL: 29,
        SIGPWR: 30,
        SIGSYS: 31,
        SIGUNUSED: 31 } },
  arch: [Function],
  platform: [Function],
  tmpdir: [Function],
  tmpDir: [Function],
  getNetworkInterfaces: [Function: deprecated],
  EOL: '\n',
  endianness: [Function] }

转换后的代码给了我这个输出

{ endianness: [Function],
  hostname: [Function],
  loadavg: [Function],
  uptime: [Function],
  freemem: [Function],
  totalmem: [Function],
  cpus: [Function],
  type: [Function],
  release: [Function],
  getNetworkInterfaces: [Function],
  networkInterfaces: [Function],
  arch: [Function],
  platform: [Function],
  tmpDir: [Function],
  tmpdir: [Function],
  EOL: '\n' }

我下载并安装了babel插件＆＃34; transform-inline-environment-variables＆＃34;我的.babelrc包含行

"plugins": ["transform-inline-environment-variables"]

但这似乎没有做任何事情。我究竟做错了什么？这个应用程序需要知道它运行的主机 - 它可能在不同的主机上运行，并且需要根据主机的名称做不同的事情。

感激不尽的任何帮助。这是我第一次涉足服务器端JavaScript。

根据要求，已编译的代码：

!function(n){function t(e){if(r[e])return r[e].exports;var o=r[e]={i:e,l:!1,exports:{}};return n[e].call(o.exports,o,o.exports,t),o.l=!0,o.exports}var r={};t.m=n,t.c=r,t.i=function(n){return n},t.d=function(n,r,e){t.o(n,r)||Object.defineProperty(n,r,{configurable:!1,enumerable:!0,get:e})},t.n=function(n){var r=n&&n.__esModule?function(){return n.default}:function(){return n};return t.d(r,"a",r),r},t.o=function(n,t){return Object.prototype.hasOwnProperty.call(n,t)},t.p="",t(t.s=1)}([function(n,t,r){"use strict";t.endianness=function(){return"LE"},t.hostname=function(){return"undefined"!=typeof location?location.hostname:""},t.loadavg=function(){return[]},t.uptime=function(){return 0},t.freemem=function(){return Number.MAX_VALUE},t.totalmem=function(){return Number.MAX_VALUE},t.cpus=function(){return[]},t.type=function(){return"Browser"},t.release=function(){return"undefined"!=typeof navigator?navigator.appVersion:""},t.networkInterfaces=t.getNetworkInterfaces=function(){return{}},t.arch=function(){return"javascript"},t.platform=function(){return"browser"},t.tmpdir=t.tmpDir=function(){return"/tmp"},t.EOL="\n"},function(n,t,r){"use strict";var e=r(0),o=e.hostname();console.log(e),console.log(o)}]);

这一切对我来说都很可怕。我一直在编写JavaScript，因为它是1995年的LiveScript，而且babel的输出总是让我感到困惑，LOL。

Answer 1

事实证明，导致问题的是webpack配置。 Jaromanda X注意到转换后的代码是针对浏览器而不是节点，并且快速谷歌搜索提出了这个问题：Webpack babel config for both server and client javascript?

所以解决方案（在该问题的答案中）只是在webpack配置中添加一行：

target: 'node'

通过babel

1 个答案: