nginx-conf

nginx-conf is a node module for making changes to an nginx configuration file programmatically.

Installation

npm install nginx-conf

This library has no dependencies.

Breaking Changes

Version 2.0.0 changed the way that single directives are accessed. In short, everything is now array-indexed.

1// Pre 2.0.0:
2conf.nginx.foo.bar._value;
3
4// 2.0.0+
5conf.nginx.foo[0].bar[0]._value;

Usage

Pretend you have an nginx config file like this one.

Note that all public methods are prefixed with _ so that they (hopefully) don't clash with nginx's directives.

Note: *_content_by_lua_block directives are supported in >=v1.3.0.

1// vanilla JS: const NginxConfFile = require('nginx-conf').NginxConfFile;
2import {NginxConfFile} from '../../';
3
4const filename = `${__dirname}/../files/readme.conf`;
5
6NginxConfFile.create(filename, function (err, conf) {
7    if (err || !conf) {
8        console.log(err);
9        return;
10    }
11
12    // reading values
13    console.log('user: ' + conf.nginx.user?.[0]._value);
14    console.log('http.server.listen: ' + conf.nginx.http?.[0].server?.[0].listen?.[0]._value);
15    console.log('http.server.location.root:' + conf.nginx.http?.[0].server?.[0].location?.[3].root?.[0]._value);
16
17    //writing values
18    //NginxConfFile.create() automatically sets up a sync, so that whenever
19    //a value is changed, or a node is removed/added, the file gets updated
20    //immediately
21
22    const onFlushed = () => {
23        console.log('finished writing to disk');
24    };
25
26    conf.on('flushed', onFlushed);
27
28    //listen to the flushed event to determine when the new file has been flushed to disk
29    if (conf.nginx.events?.[0].connections) {
30        conf.nginx.events[0].connections[0]._value = 1000;
31
32        //don't write to disk when something changes
33        conf.die(filename);
34        conf.nginx.events[0].connections[0]._value = 2000; //change remains local, not in /etc/nginx.conf
35    }
36
37    //write to a different file
38    conf.live(`${filename}.bak`);
39
40    //force the synchronization
41    conf.flush();
42
43    //adding and removing directives
44    if (conf.nginx.http) {
45        conf.nginx.http[0]._add('add_header', 'Cache-Control max-age=315360000, public');
46        console.log(conf.nginx.http[0].add_header?.[0]._value); //Cache-Control max-age=315360000, public
47
48        conf.nginx.http[0]._add('add_header', 'X-Load-Balancer lb-01');
49        conf.nginx.http[0]._add('add_header', 'X-Secure true');
50
51        console.log(conf.nginx.http[0].add_header?.[0]._value); //Cache-Control max-age=315360000, public
52        console.log(conf.nginx.http[0].add_header?.[1]._value); //X-Load-Balancer lb-01
53        console.log(conf.nginx.http[0].add_header?.[2]._value); //X-Secure true
54
55        conf.nginx.http[0]._remove('add_header'); //removes add_header[0]
56        conf.nginx.http[0]._remove('add_header', 1); //removes add_header[1]
57    }
58
59    //adding a new block
60    conf.nginx.http?.[0]._add('server');
61    conf.nginx.http?.[0].server?.[0]._add('listen', '80');
62
63    //that'll create something like this:
64    /*
65      server {
66        listen 80;
67      }
68    */
69
70    //multiple blocks
71    conf.nginx.http?.[0]._add('server');
72    conf.nginx.http?.[0].server?.[1]._add('listen', '443');
73
74    /*
75      server {
76        listen 80;
77      }
78      server {
79        listen 443;
80      }
81    */
82
83    // blocks with values:
84    conf.nginx.http?.[0].server?.[1]._add('location', '/');
85    conf.nginx.http?.[0].server?.[1].location?.[0]._add('root', '/var/www/example.com');
86
87    /*
88      server {
89        location / {
90          root /var/www/example.com;
91        }
92      }
93    */
94
95    // you can also create empty blocks
96    conf.nginx.http?.[0]._add('events', '', []); // events { }
97
98    // lua blocks also work, but you can't put a mismatched "{" or "}" in a comment!
99    conf.nginx.http?.[0].server?.[0].location?.[0]._addVerbatimBlock('rewrite_by_lua_block', '\n\
100        ngx.say("this is a lua block!")\n\
101        res = ngx.location.capture("/memc",\n\
102          { args = { cmd = "incr", key = ngx.var.uri } }\n\
103        )'
104    );
105
106    // remove old listener
107    conf.off('flushed', onFlushed);
108
109    // kill process when done writing to disk
110    conf.on('flushed', () => {
111        console.log('finished writing to disk, exiting');
112        process.exit();
113    });
114
115    conf.flush();
116});

Comments

Support for comments is supported-ish. Comments are attached to directives, and will always be rendered above the directive when using toString() (or _getString()).

Comments can be added, removed and updated via the _comments array on a node.

1console.log(conf.nginx.events[0].use[0]._comments.length); // 1
2console.log(conf.nginx.events[0].use[0]._comments[0]); // use [ kqueue | rtsig | epoll | /dev/poll | select | poll ];
3
4//remove the comment
5conf.nginx.events[0].use[0]._comments.splice(0, 1);
6
7//add a new one
8conf.nginx.events[0].use[0]._comments.push('my new comment');
9console.log(conf.nginx.events[0].use[0]._comments.length); // 1
10console.log(conf.nginx.events[0].use[0]._comments[0]); //my new comment
11
12//update a comment's text
13conf.nginx.events[0].use[0]._comments[0] = 'updated';
14console.log(conf.nginx.events[0].use[0]._comments[0]); //updated

If the comment is in a weird place (like in the middle of a directive), it'll still be attached to the node. If it's after the directive (after the semicolon or closing brace), it will be attached to the next node, or ignored if it's at the end of the file.

Assuming this nginx configuration:

1foo #comment
2bar;

You will have this object structure:

1console.log(conf.nginx.foo[0]._value); //bar
2console.log(conf.nginx.foo[0]._comments[0]); //comment

But if the comment comes after:

1foo bar;
2#comment

1console.log(conf.nginx.foo[0]._value); //bar
2console.log(conf.nginx.foo[0]._comments.length); //0

Parser options

Support for go template syntax is provided via NginxParserOptions. By default, templating syntax is not supported.

To enable templating syntax, pass the following NginxParserOptions to the parser.parse or parser.parseFile function(s):

1{
2  templateSyntax: true
3}

Development

1git clone git@github.com:tmont/nginx-conf.git
2cd nginx-conf
3npm install
4npm test

If you're making changes, you should run npm run watch in a separate terminal. tsc will output the JavaScript in the dist/ directory. The tests reference the JavaScript files in dist/, not the TypeScript files elsewhere.

Only the stuff in dist/ is included in the NPM package.