Complex classes like Parameter 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 Parameter, and based on these observations, apply Extract Interface, too.
1 | <?php declare(strict_types=1); |
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34 | class Parameter |
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35 | { |
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36 | use HydratorStrategyTrait; |
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37 | |||
38 | const DEFAULT_LOCATION = 'json'; |
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39 | |||
40 | /** |
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41 | * The human-friendly name of the parameter. This is what the user will input. |
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42 | * |
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43 | * @var string |
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44 | */ |
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45 | private $name = ''; |
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46 | |||
47 | /** |
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48 | * The alias for this parameter. Although the user will always interact with the human-friendly $name property, |
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49 | * the $sentAs is what's used over the wire. |
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50 | * |
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51 | * @var string |
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52 | */ |
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53 | private $sentAs = ''; |
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54 | |||
55 | /** |
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56 | * For array parameters (for example, an array of security group names when creating a server), each array element |
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57 | * will need to adhere to a common schema. For the aforementioned example, each element will need to be a string. |
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58 | * For more complicated parameters, you might be validated an array of complicated objects. |
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59 | * |
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60 | * @var Parameter |
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61 | */ |
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62 | private $itemSchema; |
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63 | |||
64 | /** |
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65 | * For object parameters, each property will need to adhere to a specific schema. For every property in the |
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66 | * object, it has its own schema - meaning that this property is a hash of name/schema pairs. |
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67 | * |
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68 | * The *only* exception to this rule is for metadata parameters, which are arbitrary key/value pairs. Since it does |
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69 | * not make sense to have a schema for each metadata key, a common schema is use for every one. So instead of this |
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70 | * property being a hash of schemas, it is a single Parameter object instead. This single Parameter schema will |
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71 | * then be applied to each metadata key provided. |
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72 | * |
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73 | * @var []Parameter|Parameter |
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74 | */ |
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75 | private $properties; |
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76 | |||
77 | /** |
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78 | * The value's PHP type which this parameter represents; either "string", "bool", "object", "array", "NULL". |
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79 | * |
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80 | * @var string |
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81 | */ |
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82 | private $type = ''; |
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83 | |||
84 | /** |
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85 | * Indicates whether this parameter requires a value from the user. |
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86 | * |
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87 | * @var bool |
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88 | */ |
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89 | private $required; |
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90 | |||
91 | /** |
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92 | * The location in the HTTP request where this parameter will populate; either "header", "url", "query", "raw" or |
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93 | * "json". |
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94 | * |
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95 | * @var string |
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96 | */ |
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97 | private $location = ''; |
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98 | |||
99 | /** |
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100 | * Relevant to "json" location parameters only. This property allows for deep nesting through the use of |
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101 | * {@see OpenStack\Common\JsonPath}. |
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102 | * |
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103 | * @var string |
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104 | */ |
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105 | private $path = ''; |
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106 | |||
107 | /** |
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108 | * Allows for the prefixing of parameter names. |
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109 | * |
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110 | * @var string |
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111 | */ |
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112 | private $prefix = ''; |
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113 | |||
114 | /** |
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115 | * The enum values for which this param is restricted. |
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116 | * |
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117 | * @var array |
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118 | */ |
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119 | private $enum; |
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120 | |||
121 | /** |
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122 | * @param array $data |
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123 | */ |
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124 | 220 | public function __construct(array $data) |
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125 | { |
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126 | 220 | $this->hydrate($data); |
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127 | |||
128 | 220 | $this->required = (bool)$this->required; |
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129 | 102 | ||
130 | 102 | $this->stockLocation($data); |
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131 | $this->stockItemSchema($data); |
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132 | 220 | $this->stockProperties($data); |
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133 | } |
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134 | 220 | ||
135 | 220 | private function stockLocation(array $data) |
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136 | 220 | { |
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137 | 220 | $this->location = isset($data['location']) ? $data['location'] : self::DEFAULT_LOCATION; |
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138 | |||
139 | 220 | if (!AbstractParams::isSupportedLocation($this->location)) { |
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140 | throw new \RuntimeException(sprintf("%s is not a permitted location", $this->location)); |
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141 | 220 | } |
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142 | } |
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143 | 220 | ||
144 | 1 | private function stockItemSchema(array $data) |
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145 | { |
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146 | 220 | if (isset($data['items'])) { |
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147 | $this->itemSchema = new Parameter($data['items']); |
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148 | 220 | } |
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149 | } |
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150 | 220 | ||
151 | 29 | private function stockProperties(array $data) |
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152 | 29 | { |
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153 | 220 | if (isset($data['properties'])) { |
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154 | if ($this->name && stripos($this->name, 'metadata') !== false) { |
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155 | 220 | $this->properties = new Parameter($data['properties']); |
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156 | } else { |
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157 | 220 | foreach ($data['properties'] as $name => $property) { |
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158 | 42 | $this->properties[$name] = new Parameter($property + ['name' => $name]); |
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159 | 22 | } |
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160 | 22 | } |
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161 | 30 | } |
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162 | 30 | } |
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163 | 30 | ||
164 | /** |
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165 | 42 | * Retrieve the name that will be used over the wire. |
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166 | 220 | * |
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167 | * @return string |
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168 | */ |
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169 | public function getName(): string |
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173 | 97 | ||
174 | /** |
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175 | 97 | * Indicates whether the user must provide a value for this parameter. |
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176 | * |
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177 | * @return bool |
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178 | */ |
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179 | public function isRequired(): bool |
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183 | 60 | ||
184 | /** |
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185 | 60 | * Validates a given user value and checks whether it passes basic sanity checking, such as types. |
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186 | * |
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187 | * @param $userValues The value provided by the user |
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188 | * |
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189 | * @return bool TRUE if the validation passes |
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190 | * @throws \Exception If validation fails |
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191 | */ |
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192 | public function validate($userValues): bool |
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193 | { |
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194 | $this->validateEnums($userValues); |
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195 | $this->validateType($userValues); |
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196 | 195 | ||
197 | if ($this->isArray()) { |
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198 | 195 | $this->validateArray($userValues); |
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199 | 194 | } elseif ($this->isObject()) { |
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200 | $this->validateObject($userValues); |
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201 | 193 | } |
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202 | 13 | ||
203 | 192 | return true; |
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204 | 23 | } |
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205 | 22 | ||
206 | private function validateEnums($userValues) |
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207 | 191 | { |
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208 | if (!empty($this->enum) && $this->type == 'string' && !in_array($userValues, $this->enum)) { |
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209 | throw new \Exception(sprintf( |
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210 | 195 | 'The only permitted values are %s. You provided %s', implode(', ', $this->enum), print_r($userValues, true) |
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211 | )); |
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212 | 195 | } |
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213 | 1 | } |
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214 | 1 | ||
215 | 1 | private function validateType($userValues) |
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216 | { |
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217 | 194 | if (!$this->hasCorrectType($userValues)) { |
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218 | throw new \Exception(sprintf( |
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219 | 194 | 'The key provided "%s" has the wrong value type. You provided %s (%s) but was expecting %s', |
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220 | $this->name, print_r($userValues, true), gettype($userValues), $this->type |
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221 | 194 | )); |
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222 | 3 | } |
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223 | 3 | } |
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224 | 3 | ||
225 | 3 | private function validateArray($userValues) |
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226 | { |
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227 | 193 | foreach ($userValues as $userValue) { |
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228 | $this->itemSchema->validate($userValue); |
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229 | 13 | } |
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230 | } |
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231 | 13 | ||
232 | 13 | private function validateObject($userValues) |
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233 | 12 | { |
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234 | 12 | foreach ($userValues as $key => $userValue) { |
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235 | $property = $this->getNestedProperty($key); |
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236 | 23 | $property->validate($userValue); |
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237 | } |
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238 | 23 | } |
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239 | 23 | ||
240 | 22 | /** |
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241 | 22 | * Internal method which retrieves a nested property for object parameters. |
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242 | 22 | * |
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243 | * @param string $key The name of the child parameter |
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244 | * |
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245 | * @returns Parameter |
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246 | * @throws \Exception |
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247 | */ |
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248 | private function getNestedProperty($key): Parameter |
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258 | |||
259 | 1 | /** |
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260 | * Internal method which indicates whether the user value is of the same type as the one expected |
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261 | * by this parameter. |
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262 | * |
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263 | * @param $userValue The value being checked |
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264 | * |
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265 | * @return bool |
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266 | */ |
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267 | private function hasCorrectType($userValue): bool |
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295 | |||
296 | 193 | /** |
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297 | * Indicates whether this parameter represents an array type |
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298 | 193 | * |
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299 | * @return bool |
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300 | */ |
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301 | public function isArray(): bool |
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305 | |||
306 | 192 | /** |
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307 | * Indicates whether this parameter represents an object type |
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308 | 192 | * |
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309 | * @return bool |
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310 | */ |
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311 | 185 | public function isObject(): bool |
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315 | |||
316 | public function getLocation(): string |
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320 | |||
321 | /** |
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322 | * Verifies whether the given location matches the parameter's location. |
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323 | 1 | * |
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324 | * @param $value |
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325 | 1 | * |
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326 | * @return bool |
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327 | */ |
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328 | public function hasLocation($value): bool |
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332 | |||
333 | 68 | /** |
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334 | * Retrieves the parameter's path. |
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335 | 68 | * |
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336 | * @return string|null |
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337 | */ |
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338 | public function getPath(): string |
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342 | |||
343 | 20 | /** |
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344 | * Retrieves the common schema that an array parameter applies to all its child elements. |
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345 | 20 | * |
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346 | * @return Parameter|null |
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347 | */ |
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348 | public function getItemSchema() |
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352 | |||
353 | 13 | /** |
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354 | * Sets the name of the parameter to a new value |
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355 | 13 | * |
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356 | 13 | * @param string $name |
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357 | */ |
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358 | public function setName(string $name) |
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362 | |||
363 | /** |
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364 | * Retrieves the child parameter for an object parameter. |
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365 | 22 | * |
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366 | * @param string $name The name of the child property |
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367 | 22 | * |
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368 | 12 | * @return null|Parameter |
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369 | 12 | */ |
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370 | public function getProperty(string $name) |
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379 | |||
380 | 9 | /** |
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381 | * Retrieves the prefix for a parameter, if any. |
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382 | 9 | * |
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383 | * @return string|null |
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384 | */ |
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385 | 16 | public function getPrefix(): string |
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389 | |||
390 | public function getPrefixedName(): string |
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394 | } |
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395 |