A proxy image server

npm install substitute
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A proxy image server. This is a rewrite version of camo.

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Install with npm:

$ npm install substitute -g

Quick Help

$ substitute -h

  Usage: substitute [options]


    -b, --bind <port>      The port or unix path to listen
    --host <host>          The hostname to listen [localhost]
    --path <path>          The pathname to listen [null]
    -c, --config <file>    Specify a configuration file
    -r, --redirects <num>  Max redirects allowed, default is 4
    -s, --secret <token>   A secret token to encrypto urls
    -V, --version          Display the version
    -h, --help             Display this help menu

URL Formats

Unlike camo, substitute supports only one URL Format:<reverse-domain>/<digest>/<image-path>

The <digest> is a 32 character hex encoded HMAC digest with a secret in md5 hash. And the <image-path> should be an ecoded/escaped replaced '/' uri.

Browser Support

You can get the browser client with component(1):

$ component install lepture/substitute

And generate new src with:

var substitute = require('substitute');
substitute.server = '';
substitute.secret = 'a secret that match the server secret';

var newSrc ='http://path/to/image');

// replace all image src
var newHtml = substitute.image(html);


Test it manally, start a server:

$ substitute

And then visit: this link.

Test it automatically with mocha:

$ make test

You can also test the client part with:

$ make test-client


var substitute = require('substitute');

    maxRedirects: 5

var server = substitute(secret, options);
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