wellrested/src/pjdietz/WellRESTed/RouteBuilder.php

260 lines
8.2 KiB
PHP

<?php
/**
* pjdietz\WellRESTed\RouteBuilder
*
* @author PJ Dietz <pj@pjdietz.com>
* @copyright Copyright 2014 by PJ Dietz
* @license MIT
*/
namespace pjdietz\WellRESTed;
use pjdietz\WellRESTed\Exceptions\ParseException;
use pjdietz\WellRESTed\Interfaces\HandlerInterface;
use pjdietz\WellRESTed\Routes\RegexRoute;
use pjdietz\WellRESTed\Routes\StaticRoute;
use pjdietz\WellRESTed\Routes\TemplateRoute;
/**
* Class for facilitating constructing Routers.
*/
class RouteBuilder
{
/** @var string Regex pattern to use for URI template patters. */
private $defaultVariablePattern;
/** @var string Common prefix to affix to handler class names. */
private $handlerNamespace;
/** @var array Associative array of variable names and regex patterns. */
private $templateVariablePatterns;
/**
* Contruct and return an array of routes.
*
* If $data is a string, buildRoutes() will parse it as JSON with json_decode.
* <br /><br />
* If $data is an array, buildRoutes() assumes each item in the array is
* an object it can translate into a route.
* <br /><br />
* If $data is an object, buildRoutes() assumes it will have a "routes"
* property with an array value that is a collection of objects to
* translate into routes. Any other properties will be read with
* readConfiguration()
*
* @param string|array|object $data Description of routes to build.
* @return array List of routes to add to a router.
* @throws Exceptions\ParseException
*/
public function buildRoutes($data)
{
// If $data is a string, attempt to parse it as JSON.
if (is_string($data)) {
$data = json_decode($data);
if (is_null($data)) {
throw new ParseException("Unable to parse as JSON.");
}
}
// Locate the list of routes. This should be one of these:
// - If $data is an object, $data->routes
// - If $data is an array, $data
if (is_array($data)) {
$dataRoutes = $data;
} elseif (is_object($data) && isset($data->routes) && is_array($data->routes)) {
$dataRoutes = $data->routes;
$this->readConfiguration($data);
} else {
throw new ParseException("Unable to parse. Missing array of routes.");
}
// Build a route instance and append it to the list.
$routes = array();
foreach ($dataRoutes as $item) {
$routes[] = $this->buildRoute($item);
}
return $routes;
}
/**
* Parse an object and update the instances with the new configuration.
*
* ->handlerNamespace is passed to setHandlerNamesapce()
* <br /></br />
* ->variablePattern is passed to setDefaultVariablePattern()
* <br /><br />
* ->vars is passed to setTemplateVars()
*
* @param object
*/
public function readConfiguration($data)
{
if (isset($data->handlerNamespace)) {
$this->setHandlerNamespace($data->handlerNamespace);
}
if (isset($data->variablePattern)) {
$this->setDefaultVariablePattern($data->variablePattern);
}
if (isset($data->vars)) {
$this->setTemplateVars((array) $data->vars);
}
}
/**
* Return the string to prepend to handler class names.
*
* @return string
*/
public function getHandlerNamespace()
{
return $this->handlerNamespace;
}
/**
* Set the prefix to prepend to handler class names.
*
* @param mixed $handlerNamespace
*/
public function setHandlerNamespace($handlerNamespace = "")
{
$this->handlerNamespace = $handlerNamespace;
}
/**
* Return an associative array of variable names and regex patterns.
*
* @return mixed
*/
public function getTemplateVars()
{
return $this->templateVariablePatterns;
}
/**
* Set the array of template variable patterns.
*
* Keys are names of variables for use in URI template (do not include {}).
* Values are regex patterns or any of the following special names: SLUG,
* ALPHA, ALPHANUM, DIGIT, NUM.
* <br /><br />
* If you wish to use additional named patterns, subclass RouteBuilder and
* override getTemplateVariablePattern.
*
* @param array $vars Associative array of variable name => pattern
*/
public function setTemplateVars(array $vars)
{
foreach ($vars as $name => $var) {
$vars[$name] = $this->getTemplateVariablePattern($var);
}
$this->templateVariablePatterns = $vars;
}
/**
* Return the default regex pattern to use for URI template variables.
*
* @return string
*/
public function getDefaultVariablePattern()
{
return $this->defaultVariablePattern;
}
/**
* Set the default regex pattern to use for URI template variables.
*
* $defaultVariablePattern may be a regex pattern or one of the following:
* SLUG, ALPHA, ALPHANUM, DIGIT, NUM.
* <br /><br />
* If you wish to use additional named patterns, subclass RouteBuilder and
* override getTemplateVariablePattern.
*
* @param mixed $defaultVariablePattern
*/
public function setDefaultVariablePattern($defaultVariablePattern)
{
$this->defaultVariablePattern = $this->getTemplateVariablePattern($defaultVariablePattern);
}
/**
* Create and return an appropriate route given an object describing a route.
*
* $item must contain a "handler" property providing the classname for the
* HandlerInterface to call getResponse() on if the route matches. "handler"
* may be fully qualified and begin with "\". If it does not begin with "\",
* the instance's $handlerNamespace is affixed to the begining.
* <br /><br />
* $item must also contain a "path", "template", or "pattern" property to
* indicate how to create the StaticRoute, TemplateRoute, or RegexRoute.
*
* @param object|array $item
* @return HandlerInterface
* @throws Exceptions\ParseException
*/
protected function buildRoute($item)
{
// Determine the handler for this route.
if (isset($item->handler)) {
$handler = $item->handler;
if ($handler[0] != "\\") {
$handler = $this->getHandlerNamespace() . "\\" . $handler;
}
} else {
throw new ParseException("Unable to parse. Route is missing a handler.");
}
// Static Route
if (isset($item->path)) {
return new StaticRoute($item->path, $handler);
}
// Template Route
if (isset($item->template)) {
$vars = isset($item->vars) ? (array) $item->vars : array();
foreach ($vars as $name => $var) {
$vars[$name] = $this->getTemplateVariablePattern($var);
}
if ($this->templateVariablePatterns) {
$vars = array_merge($this->templateVariablePatterns, $vars);
}
return new TemplateRoute($item->template, $handler, $this->getDefaultVariablePattern(), $vars);
}
// Regex Route
if (isset($item->pattern)) {
return new RegexRoute($item->pattern, $handler);
}
return null;
}
/**
* Provide a regular expression pattern given a name.
*
* The names SLUG, ALPHA, ALPHANUM, DIGIT, NUM convert to regex patterns.
* Anything else passes through as is.
* <br /><br />
* If you wish to use additional named patterns, subclass RouteBuilder and
* override getTemplateVariablePattern.
*
* @param string $variable Regex pattern or name (SLUG, ALPHA, ALPHANUM, DIGIT, NUM
* @return string
*/
protected function getTemplateVariablePattern($variable)
{
switch ($variable) {
case "SLUG":
return TemplateRoute::RE_SLUG;
case "ALPHA":
return TemplateRoute::RE_ALPHA;
case "ALPHANUM":
return TemplateRoute::RE_ALPHANUM;
case "DIGIT":
case "NUM":
return TemplateRoute::RE_NUM;
default:
return $variable;
}
}
}