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readme.md

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+# uri-qr-generator
+
+A simple HTTP API to generate URI QR codes in SVG format
+
+## Setup
+
+```
+git clone https://github.com/orestes/uri-qr-generator.git
+cd uri-qr-generator
+npm install
+cp config.template.json config.json
+node server.js
+```
+
+If everything's working correctly, you'll get the following message:
+
+```
+quaero-qr-generator is now listening on port 8080
+```
+
+## Configuration
+
+Edit `config.json`:
+
+| Parameter | Default |  Use |
+|-|-|-|
+| port | `80` | Where the HTTP server should listen. |
+| uriPrefix | `""`|   A prefix prepended to the all the URIs |
+| paramName | `uri` | The `GET` param name containing the URI to encode as a QR Code. |
+w
+## Usage
+
+Make an `HTTP GET` request to `https://server:port/?uri=https:%2F%2Fsome-server/a/b`. The response is a QR Code in SVG format. This is the QR encoded representation of `https://some-server/a/b` URI.
+
+Remember to correctly encode `GET` params.
+
+### Embeddeding QR codes as HTML images
+
+Since we're using GET params, we can use the request URI as an image source, which be cached by browsers, proxies, etc...
+
+If your `port` parameter is set to `80` (the default HTTP port in browsers) in `config.json`, you can skip the port when using the images
+
+`<img src="https://server/?uri=https:%2F%2Fsome-server/a/b" alt="https://some-server/a/b" />`
+
+### Anti-abuse configuration
+
+Unless you protect your API (by proxying through some other HTTP server, for example), anyone making requests to your service could be generating QR codes for free using your resources.
+
+A typical use case is generating QR codes for a single domain name. Set your **uriPrefix** to `"https://my-domain"` and then pass relative URLs in your `GET` param values. Since every QR code will now start with your domain name there's no use for anyone else.
+
+You should also rename the GET param to `path` so the API requests are more clear:
+
+Example `config.json`
+
+```
+{
+  "port": 8080,
+  "uriPrefix": "https://my-domain",
+  "paramName": "path"
+}
+```
+
+Now, `http://server:port/?path=/a/b` will return a QR Code in SVG format, pointing to `https://my-domain/a/b`
+
+## Troubleshooting
+
+Make sure the HTTP port (*default: 8080*) is not in use by some other process and/or change the HTTP port in the configuration. In some operating systems, you cannot listen on ports under 1000 without root permissions.
+
+Feel free to [open an issue here](https://github.com/orestes/uri-qr-generator/issues)
+
+## License
+The MIT License (MIT)
+
+Copyright (c) 2016 Orestes Carracedo
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.