PHP API Client

PHP has been around for a long time. It is most useful when building web applications. However, as the sample code below shows PHP is equally suited for writing CLI applications.

You can download the fully working script here.

smartfileapi.php

#!/usr/bin/php
<?
# These constants are needed to access the API.
define("API_URL", "http://app.smartfile.com/api/1");
define("API_KEY", "api-key");
define("API_PWD", "api-password");

# This function performs an HTTP request and parses the response.
# It raises an exception if the server cannot be contacted or if
# the server returns a status other than 201. Any status other
# that 201 results in the exception receiving the HTTP status in
# addition to the returned error message.
function http_request($uri, $data=null, $method) {
    $url = API_URL . $uri;
    $url_parts = parse_url($url);
    $host_header = $url_parts['host'];
    if (array_key_exists('port', $url_parts)) {
        $port = $url_parts['port'];
        $host_header .= ":" . $port;
    } else
        $port = 80;
    $data = http_build_query($data);
    $auth = base64_encode(API_KEY . ":" . API_PWD);
    # We use fsockopen to perform our HTTP request as that is the
    # most compatible way of doing so. This method should work on
    # just about any PHP installation and does not require cURL
    # or any other HTTP extensions.
    $fp = @fsockopen($url_parts['host'], $port, $errno, $errstr, 30); 
    if (!$fp)
        throw new Exception("Error contacting Server: " . $errstr);
    fputs($fp,  $method . " " . $url_parts['path'] . " HTTP/1.1\r\n" .
                "Host: " . $host_header . "\r\n" .
                "User-Agent: PHP SmartFile API Sample Client\r\n" .
                "Authorization: Basic " . $auth . "\r\n" .
                "Content-Type: application/x-www-form-urlencoded\r\n" .
                "Content-Length: " . strlen($data) . "\r\n" .
                "\r\n");
    if ($method == 'POST')
        fputs($fp, $data);
    $response = '';
    while ($line = fread($fp, 4096)) {
        $response .= $line;
    }
    fclose($fp);

    # strip the HTTP headers:
    $sep = strpos($response, "\r\n");
    $http_status = substr($response, 0, $sep);
    list($ignored, $http_status, $ignored) = split(" ", $http_status);
    if ($http_status != '201') {
        # Non-201 status, so parse out the message and inform the caller
        # via an Exception.
        $sep = strpos($response, "\r\n\r\n");
        $response = substr($response, $sep + 4);
        $response = json_decode($response);
        throw new Exception($response->{'message'}, $http_status);
    }
}

# This function makes the User add API call. It uses the http_request
# function to handle the transport. Additional API calls could be supported
# simply by writing additional wrappers that create the $data array and
# use http_request to do the grunt work.
function create_user($fullname, $username, $password, $email) {
    $data = array(
        "name"          => $fullname,
        "username"      => $username,
        "password"      => $password,
        "email"         => $email,
    );
    http_request('/users/add/', $data, 'POST');
}

# A short function to ask the user a question and return their
# response.
function prompt($prompt='') {
    echo $prompt;
    return trim(fgets(STDIN));
}

function main() {
    # Ask the user for the required parameters. These will be
    # passed to the API via an HTTP POST request.
    $fullname = prompt('Please enter a full name: ');
    $username = prompt('Please enter a username: ');
    $password = prompt('Please enter a password: ');
    $email = prompt('Please enter an email address: ');
    try {
        # Try to create the new user...
        create_user($fullname, $username, $password, $email);
        print("Successfully created user " . $username . ".\n");
    }
    catch (Exception $e) {
        # Print the error message from the server on failure.
        print("Error creating user " . $username . ": " . $e->getMessage() . ".\n");
    }
}

# Start things off in main()
main();
?>