使用NCONF捕获命令行参数

I have a simple node.js backend script and I want to capture command line arguments along with the keys/values from a config.json file and environment variables. The second two I am having no problem with, but I am having nearly inexplicable trouble capturing the command line args.

我有一个简单的node.js后端脚本，我想捕获命令行参数以及config.json文件和环境变量中的键/值。第二个我没有问题，但我在捕获命令行args时遇到了几乎莫名其妙的麻烦。

I can capture the command line arguments this way:

我可以这样捕获命令行参数：

var nconf = require('nconf');
nconf.argv().env().file({file: './config.json'});

var csvFilePath = nconf.argv().get()._[0]; // var csvFilePath = process.argv[2];
var csvType = nconf.argv().get()._[1];     // var csvType = process.argv[3];

these two calls are equivalent to process.argv[index], except the index is changed.

这两个调用等同于process.argv [index]，但索引已更改。

There has to be a more straightforward way to capture the command line arguments but even when I debug and look through the variables that nconf yields, I still can't figure it out.

必须有一种更简单的方法来捕获命令行参数，但即使我调试并查看nconf产生的变量，我仍然无法弄明白。

Anyone with nconf experience care to help?

有nconf经验的人可以帮忙吗？

2 个解决方案

#1

I believe the best way to do this is like so:

我相信这样做的最好方法是这样的：

//contents of app.js
var nconf = require('nconf').argv();

if you call your program with the follow command line command:

如果使用follow命令行命令调用程序：

node app.js --one foo --two bar

then in your program you can access these command line args like so:

然后在您的程序中，您可以访问这些命令行args，如下所示：

var nconf = require('nconf').argv();
var one = nconf.get('one');  //one = 'foo'
var two = nconf.get('two');  //two = 'bar'

so you need the -- symbol in front of the identifier, then you can access the command line args.

所以你需要在标识符前面的 - 符号，然后你可以访问命令行args。

Frankly, as a message to the nconf module author Charlie Robbins, I think it would better to not mix everything into one big hash.

坦率地说，作为向nconf模块作者Charlie Robbins发送的消息，我认为最好不要将所有内容混合成一个大哈希。

It would be better if you did this instead:

如果你这样做会更好：

var foo = nconf.argv.get('one');
var node_env = nconf.env.get('NODE_ENV');

I think it is more intuitive and less error prone.

我认为它更直观，更不容易出错。

Also, for those starting node with 'npm start':

此外，对于那些带有'npm start'的起始节点：

to my knowledge you need two extra hyphens like so:

据我所知，你需要两个额外的连字符，如下所示：

npm start -- --one foo --two bar

with the extra hyphens/dashes you let Bash know that the args are for your node.js executable, not for the NPM node.js executable

使用额外的连字符/破折号，你让Bash知道args是你的node.js可执行文件，而不是NPM node.js可执行文件

#2

Slightly shorter/cleaner:

略短/清洁：

var nconf = require('nconf');
nconf.argv().env().file({file: './config.json'});

var csvFilePath = nconf.get('_')[0]; // var csvFilePath = process.argv[2];
var csvType = nconf.get('_')[1];     // var csvType = process.argv[3];

If you name your parameter (say, --foo=bar or -f bar), then you can use .get('foo') or .get('f') rather than using the array index.

如果您为参数命名（例如， - foo = bar或-f bar），则可以使用.get（'foo'）或.get（'f'）而不是使用数组索引。

#1