[5.5] [WIP] Transformable Responses

src/Illuminate/Contracts/Support/Transformable.php

@@ -0,0 +1,13 @@
+<?php
+
+namespace Illuminate\Contracts\Support;
+
+interface Transformable
+{
+    /**
+     * Get data to apply transformations.
+     *
+     * @return array
+     */
+    public function getTransformableData();
+}

src/Illuminate/Http/TransformableResponse.php

@@ -0,0 +1,383 @@
+<?php
+
+namespace Illuminate\Http;
+
+use Exception;
+use Illuminate\Support\Arr;
+use Illuminate\Support\Str;
+use Illuminate\Validation\ValidationData;
+use Illuminate\Contracts\Support\Arrayable;
+use Illuminate\Contracts\Support\Transformable;
+
+class TransformableResponse extends JsonResponse
+{
+    /**
+     * Constructor.
+     *
+     * @param  mixed  $data
+     * @param  int  $status
+     * @param  array  $headers
+     * @param  int  $options
+     * @return void
+     */
+    public function __construct($data = null, $status = 200, $headers = [], $options = 0)
+    {
+        if (is_array($data)) {
+            $transformedData = $this->transform($data);
+        } elseif ($data instanceof Transformable) {
+            $transformedData = $this->transform($this->getTransformableData());
+        } elseif ($data instanceof Collection) {
+            $transformedData = $this->handleCollectionTransformation($data);
+        } elseif ($data instanceof Arrayable) {
+            $transformedData = $this->transform($data->toArray());
+        }
+
+        parent::__construct($transformedData, $status, $headers, $options);
+
+        $this->original = $data;
+    }
+
+    /**
+     * Handle how a collection will be transformed.
+     *
+     * @param  \Illuminate\Support\Collection  $data
+     * @return mixed
+     */
+    protected function handleCollectionTransformation(Collection $data)
+    {
+        return $this->transform(
+            $data->map(function ($item) {
+                if ($item instanceof Transformable) {
+                    return $item->getTransformableData();
+                } elseif ($item instanceof Arrayable) {
+                    return $item->toArray();
+                }
+
+                return $item;
+            })
+            ->toArray()
+        );
+    }
+
+    /**
+     * Transforms the response data.
+     *
+     * @param  array  $data
+     * @return array
+     */
+    protected function transform(array $data)
+    {
+        if (! empty($data) && method_exists($this, 'visibilityRules')) {
+            $data = $this->applyVisibilityRules(
+                $data,
+                $this->visibilityRules()
+            );
+        }
+
+        if (! empty($data) && method_exists($this, 'castingRules')) {
+            $data = $this->applyCastingRules(
+                $data,
+                $this->castingRules()
+            );
+        }
+
+        if (! empty($data) && method_exists($this, 'mutationRules')) {
+            $data = $this->applyMutationRules(
+                $data,
+                $this->mutationRules()
+            );
+        }
+
+        if (! empty($data) && method_exists($this, 'renamingRules')) {
+            $data = $this->applyRenamingRules(
+                $data,
+                $this->renamingRules()
+            );
+        }
+
+        return $data;
+    }
+
+    /**
+     * Apply visibility rules to given data.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function applyVisibilityRules(array $data, array $rules)
+    {
+        if (empty($rules = $this->resolveWildcardRules($data, $rules))) {
+            return $data;
+        }
+
+        $data = $this->performShowFields($data, $rules);
+        $data = $this->performHideFields($data, $rules);
+
+        return $data;
+    }
+
+    /**
+     * Apply rules over the fields that must be displayed.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function performShowFields(array $data, array $rules)
+    {
+        if (empty($applicableRules = array_filter($rules))) {
+            return $data;
+        }
+
+        return array_reduce(array_keys($applicableRules),
+            function ($transformedData, $attribute) use ($data) {
+                if ($value = Arr::get($data, $attribute)) {
+                    Arr::set($transformedData, $attribute, $value);
+                }
+
+                return $transformedData;
+            },
+        []);
+    }
+
+    /**
+     * Apply rules over the fields that must be hidden.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function performHideFields(array $data, array $rules)
+    {
+        $applicableRules = array_filter($rules, function ($rule) {
+            return ! $rule;
+        });
+
+        return array_reduce(array_keys($applicableRules),
+            function ($transformedData, $rule) {
+                Arr::forget($transformedData, $rule);
+
+                return $transformedData;
+            },
+        $data);
+    }
+
+    /**
+     * Apply casting rules to given data.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function applyCastingRules(array $data, array $rules)
+    {
+        if (empty($rules = $this->resolveWildcardRules($data, $rules))) {
+            return $data;
+        }
+
+        return array_reduce(array_keys($rules),
+            function ($data, $rule) use ($rules) {
+                if (Arr::has($data, $rule)) {
+                    $value = $this->performCasting(
+                        Arr::get($rules, $rule),
+                        Arr::get($data, $rule)
+                    );
+
+                    Arr::set($data, $rule, $value);
+                }
+
+                return $data;
+            },
+        $data);
+    }
+
+    /**
+     * Performs casting to given value based on given type.
+     *
+     * @param  string  $type
+     * @param  mixed  $value
+     * @return mixed
+     */
+    protected function performCasting($type, $value)
+    {
+        switch ($type) {
+            case 'int':
+            case 'integer':
+                return (int) $value;
+            case 'real':
+            case 'float':
+            case 'double':
+                return (float) $value;
+            case 'string':
+                return (string) $value;
+            case 'bool':
+            case 'boolean':
+                return (bool) $value;
+            default:
+                return $value;
+        }
+    }
+
+    /**
+     * Apply mutation rules to given value.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return mixed
+     */
+    public function applyMutationRules(array $data, array $rules)
+    {
+        if (empty($rules = $this->resolveWildcardRules($data, $rules))) {
+            return $data;
+        }
+
+        return array_reduce(array_keys($rules),
+            function ($data, $rule) use ($rules) {
+                if (Arr::has($data, $rule)) {
+                    $value = $this->performMutations(
+                        Arr::get($rules, $rule),
+                        Arr::get($data, $rule)
+                    );
+
+                    Arr::set($data, $rule, $value);
+                }
+
+                return $data;
+            },
+        $data);
+    }
+
+    /**
+     * Performs given mutators in given value.
+     *
+     * @param  string  $mutators
+     * @param  mixed  $value
+     * @return mixed
+     *
+     * @throws \Exception
+     */
+    public function performMutations($mutators, $value)
+    {
+        $mutators = explode('|', $mutators);
+
+        return array_reduce($mutators, function ($value, $mutator) {
+            $method = 'mutator'.Str::studly($mutator);
+
+            if (! method_exists($this, $method)) {
+                $class = static::class;
+
+                throw new Exception("No mutator [$method] defined in [$class]");
+            }
+
+            return $this->$method($value);
+        }, $value);
+    }
+
+    /**
+     * Apply renaming rules for given attribute.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function applyRenamingRules(array $data, array $rules)
+    {
+        if (empty($rules = $this->resolveWildcardRules($data, $rules))) {
+            return $data;
+        }
+
+        uksort($rules, function ($a, $b) {
+            return count(explode('.', $a)) < count(explode('.', $b));
+        });
+
+        $resultData = $this->performRenaming($data, $rules);
+
+        return array_reduce(array_keys($resultData),
+            function ($data, $attribute) use ($resultData) {
+                Arr::set($data, $attribute, $resultData[$attribute]);
+
+                return $data;
+            },
+        []);
+    }
+
+    /**
+     * Performs renaming mutators in given data.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function performRenaming(array $data, array $rules)
+    {
+        $resultData = array_reduce(array_keys($rules),
+            function ($encodedData, $rule) use ($rules) {
+                $replace = preg_replace(
+                    '/(\w|\s|\-)+$/',
+                    $rules[$rule],
+                    $rule
+                );
+
+                return str_replace('"'.$rule, '"'.$replace, $encodedData);
+            },
+        json_encode(Arr::dot($data)));
+
+        return json_decode($resultData, true);
+    }
+
+    /**
+     * Resolve array rules generating a new rule for every '*' symbol.
+     *
+     * @param  array  $data
+     * @param  array  $rules
+     * @return array
+     */
+    protected function resolveWildcardRules(array $data, array $rules)
+    {
+        return array_reduce(array_keys($rules),
+            function ($parsedRules, $rule) use ($data, $rules) {
+                if (Str::contains($rule, '*')) {
+                    $gatheredRules = array_keys(
+                        ValidationData::initializeAndGatherData($rule, $data)
+                    );
+
+                    return array_merge(
+                        $parsedRules,
+                        $this->sanitizeWildcardGatheredRules(
+                            $rule,
+                            $gatheredRules,
+                            $rules[$rule]
+                        )
+                    );
+                }
+
+                $parsedRules[$rule] = $rules[$rule];
+
+                return $parsedRules;
+            }, []);
+    }
+
+    /**
+     * Sanitize rules removing those that don't appear into original rules.
+     *
+     * @param  string  $rule
+     * @param  array  $gatheredRules
+     * @param  bool  $valueForValidOnes
+     * @return array
+     */
+    protected function sanitizeWildcardGatheredRules($rule, array $gatheredRules, $valueForValidOnes)
+    {
+        $pattern = '/'.str_replace('.*.', '\.([0-9])+\.', $rule).'/';
+
+        return array_reduce($gatheredRules,
+            function ($validRules, $rule) use ($pattern, $valueForValidOnes) {
+                if (preg_match($pattern, $rule)) {
+                    $validRules[$rule] = $valueForValidOnes;
+                }
+
+                return $validRules;
+            },
+        []);
+    }
+}