Complex classes like HttpDispatcher often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes. You can also have a look at the cohesion graph to spot any un-connected, or weakly-connected components.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use HttpDispatcher, and based on these observations, apply Extract Interface, too.
1 | <?php |
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37 | class HttpDispatcher implements Dispatcher |
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38 | { |
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39 | /** |
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40 | * @var HttpAsyncClient |
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41 | */ |
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42 | private $httpClient; |
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43 | |||
44 | /** |
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45 | * @var UriFactory |
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46 | */ |
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47 | private $uriFactory; |
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48 | |||
49 | /** |
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50 | * Queued requests. |
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51 | * |
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52 | * @var RequestInterface[] |
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53 | */ |
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54 | private $queue = []; |
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55 | |||
56 | /** |
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57 | * Caching proxy server host names or IP addresses. |
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58 | * |
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59 | * @var UriInterface[] |
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60 | */ |
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61 | private $servers; |
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62 | |||
63 | /** |
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64 | * Application host name and optional base URL. |
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65 | * |
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66 | * @var UriInterface[] |
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67 | */ |
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68 | private $baseUris; |
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69 | |||
70 | /** |
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71 | * If you specify a custom HTTP client, make sure that it converts HTTP |
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72 | * errors to exceptions. |
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73 | * |
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74 | * If your proxy server IPs can not be statically configured, extend this |
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75 | * class and overwrite getServers. Be sure to have some caching in |
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76 | * getServers. |
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77 | * |
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78 | * @param string[] $servers Caching proxy server hostnames or IP |
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79 | * addresses, including port if not port 80. |
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80 | * E.g. ['127.0.0.1:6081'] |
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81 | * @param string|string[] $baseUris Default application hostnames, optionally |
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82 | * including base URL, for purge and refresh |
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83 | * requests (optional). At least one is required if |
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84 | * you purge and refresh paths instead of |
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85 | * absolute URLs. A request will be sent for each |
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86 | * base URL. |
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87 | * @param HttpAsyncClient|null $httpClient Client capable of sending HTTP requests. If no |
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88 | * client is supplied, a default one is created |
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89 | * @param UriFactory|null $uriFactory Factory for PSR-7 URIs. If not specified, a |
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90 | * default one is created |
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91 | 38 | */ |
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92 | public function __construct( |
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127 | 1 | ||
128 | /** |
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129 | * {@inheritdoc} |
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130 | 32 | */ |
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131 | 32 | public function invalidate(RequestInterface $invalidationRequest, $validateHost = true) |
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145 | 33 | ||
146 | /** |
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147 | 33 | * {@inheritdoc} |
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148 | */ |
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149 | 33 | public function flush() |
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188 | |||
189 | /** |
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190 | * Get the list of servers to send invalidation requests to. |
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191 | * |
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192 | * @return UriInterface[] |
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193 | */ |
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194 | protected function getServers() |
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198 | |||
199 | 32 | /** |
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200 | * Duplicate a request for each caching server. |
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201 | 32 | * |
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202 | * @param RequestInterface $request The request to duplicate for each configured server |
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203 | * |
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204 | * @return RequestInterface[] |
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205 | 32 | */ |
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206 | 30 | private function fanOut(RequestInterface $request) |
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240 | 32 | ||
241 | /** |
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242 | * Looks at a given request and returns an array of requests incorporating |
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243 | * every configured base URI. |
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244 | 32 | * |
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245 | * @param RequestInterface $request The request to modify for every configured base URI |
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246 | * |
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247 | * @return RequestInterface[] |
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248 | */ |
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249 | private function requestToBaseUris(RequestInterface $request) |
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283 | |||
284 | /** |
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285 | * Set caching proxy server URI objects, validating them. |
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286 | * |
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287 | * @param string[] $servers Caching proxy proxy server hostnames or IP |
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288 | * addresses, including port if not port 80. |
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289 | * E.g. ['127.0.0.1:6081'] |
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290 | * |
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291 | * @throws InvalidUrlException If server is invalid or contains URL |
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292 | * parts other than scheme, host, port |
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293 | */ |
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294 | private function setServers(array $servers) |
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301 | 1 | ||
302 | 1 | /** |
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303 | 1 | * Set application base URI that will be prefixed to relative purge and |
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304 | * refresh requests, and validate it. |
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305 | * |
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306 | * @param array $baseUris Your application’s base URIs |
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307 | * |
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308 | * @throws InvalidUrlException If the base URI is not a valid URI |
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309 | */ |
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310 | 38 | private function setBaseUris(array $baseUris = []) |
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322 | |||
323 | /** |
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324 | 36 | * Filter a URL. |
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325 | 36 | * |
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326 | 36 | * Prefix the URL with "http://" if it has no scheme, then check the URL |
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327 | 36 | * for validity. You can specify what parts of the URL are allowed. |
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328 | 1 | * |
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329 | * @param string $uriString |
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330 | * @param string[] $allowedParts Array of allowed URL parts (optional) |
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331 | * |
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332 | 35 | * @return UriInterface Filtered URI (with default scheme if there was no scheme) |
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333 | * |
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334 | * @throws InvalidUrlException If URL is invalid, the scheme is not http or |
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335 | * contains parts that are not expected |
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336 | */ |
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337 | private function filterUri($uriString, array $allowedParts = []) |
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366 | |||
367 | /** |
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368 | * Build a request signature based on the request data. Unique for every different request, identical |
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369 | * for the same requests. |
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370 | * |
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371 | * This signature is used to avoid sending the same invalidation request twice. |
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372 | * |
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373 | * @param RequestInterface $request An invalidation request |
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374 | * |
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375 | * @return string A signature for this request |
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376 | */ |
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377 | private function getRequestSignature(RequestInterface $request) |
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384 | } |
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385 |
In PHP, under loose comparison (like
==
, or!=
, orswitch
conditions), values of different types might be equal.For
integer
values, zero is a special case, in particular the following results might be unexpected: