HTTP Proxy support to access openstreetmap.org

[ArnaultMICHEL]

Hi,

I've tested your project recently : congratulations, you've done a great job!

I wish to contribute to three improvements that I consider essential for the sovereign project I am working on.

This is the first proposal, a PR will come soon.

Feature description

As we are on a private network without direct internet access, we need to configure a proxy to reach openstreetmap.org
if the proxy require authentication, we should provide the credentials

Note : the cache on the proxy should speed up the http traffic ;)

Code impact

conf/config.inc.php

I propose to store a default config that disable the proxy by default.
This can be reactivated in conf/config.inc.local.php.

# Proxy settings
$use_proxy=false;
$proxy_host = "mysquidproxy.example.com";
$proxy_port = 3128;
$proxy_use_ssl = false;
$proxy_auth = false;
$proxy_auth_user = "user";
$proxy_auth_pass = "password";

htdocs/geocode.php

as explained here, we need to add the proxy config before calling stream_context_create

$http_settings = array(
        # Set timeout to 5 seconds
        'timeout' => 5,
        'user_agent' => "LTB White-Pages address geocoding/1.0"
);
if ($use_proxy) {
    $http_settings['proxy'] = "tcp://" . $proxy_host . ":" . $proxy_port;
    if ($proxy_use_ssl) {
        $http_settings['request_fulluri'] = true;
    }
    if ($proxy_auth) {
        $http_settings['header'] = "Proxy-Authorization: Basic " . base64_encode($proxy_auth_user . ":" . $proxy_auth_pass);
    }
}

$opts = array(
    'http' => $http_settings
);

$context = stream_context_create($opts);
...

Tests

I simply install squid 6.14 on my (gentoo) VM : it's working with anonymous access.
i still need to test with authentication activated, based on this simple gist config guideline

[davidcoutadeur]

Thank you for your contribution.

The feature seems interesting, we are going to review the PR.