miniflux-legacy/vendor/fguillot/picofeed/docs/favicon.markdown

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Favicon fetcher
===============
Find and download the favicon
-----------------------------
```php
use PicoFeed\Reader\Favicon;
$favicon = new Favicon;
// The icon link is https://bits.wikimedia.org/favicon/wikipedia.ico
$icon_link = $favicon->find('https://en.wikipedia.org/');
$icon_content = $favicon->getContent();
```
PicoFeed will try first to find the favicon from the meta tags and fallback to the `favicon.ico` located in the website's root if nothing is found.
- `Favicon::find()` returns the favicon absolute url or an empty string if nothing is found.
- `Favicon::getContent()` returns the favicon file content (binary content)
When the HTML page is parsed, relative links and protocol relative links are converted to absolute url.
Get Favicon file type
---------------------
It's possible to fetch the image type, this information come from the Content-Type HTTP header:
```php
$favicon = new Favicon;
$favicon->find('http://example.net/');
echo $favicon->getType();
// Will output the content type, by example "image/png"
```
Get the Favicon as Data URI
---------------------------
You can also get the whole image as Data URI.
It's useful if you want to store the icon in your database and avoid too many HTTP requests.
```php
$favicon = new Favicon;
$favicon->find('http://example.net/');
echo $favicon->getDataUri();
// Output something like that: data:image/png;base64,iVBORw0KGgoAAAANSUh.....
```
See: http://en.wikipedia.org/wiki/Data_URI_scheme
Check if a favicon link exists
------------------------------
```php
use PicoFeed\Reader\Favicon;
$favicon = new Favicon;
// Return true if the file exists
var_dump($favicon->exists('http://php.net/favicon.ico'));
```
Use personalized HTTP settings
------------------------------
Like other classes, the Favicon class support the Config object as constructor argument:
```php
use PicoFeed\Config\Config;
use PicoFeed\Reader\Favicon;
$config = new Config;
$config->setClientUserAgent('My RSS Reader');
$favicon = new Favicon($config);
$favicon->find('https://github.com');
```