prototype-better-error-handling

Author: dominikzogg

src/Error.php

@@ -4,12 +4,15 @@
 
 namespace Chubbyphp\Parsing;
 
-final class Error
+/**
+ * @phpstan-type ErrorAsJson array{code: string, template: string, variables: array<string, mixed>}
+ */
+final class Error implements \JsonSerializable
 {
     /**
      * @param array<string, mixed> $variables
      */
-    public function __construct(public string $code, public string $template, public array $variables) {}
+    public function __construct(public readonly string $code, public readonly string $template, public readonly array $variables) {}
 
     public function __toString()
     {
@@ -25,4 +28,12 @@ public function __toString()
 
         return $message;
     }
+
+    /**
+     * @return ErrorAsJson
+     */
+    public function jsonSerialize(): array
+    {
+        return ['code' => $this->code, 'template' => $this->template, 'variables' => $this->variables];
+    }
 }

src/ErrorWithPath.php

@@ -0,0 +1,22 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Chubbyphp\Parsing;
+
+/**
+ * @phpstan-type ErrorAsJson array{code: string, template: string, variables: array<string, mixed>}
+ * @phpstan-type ErrorWithPathJson array{error: ErrorAsJson, path: string}
+ */
+final class ErrorWithPath implements \JsonSerializable
+{
+    public function __construct(public readonly Error $error, public readonly string $path) {}
+
+    /**
+     * @return ErrorWithPathJson
+     */
+    public function jsonSerialize(): array
+    {
+        return ['error' => $this->error->jsonSerialize(), 'path' => $this->path];
+    }
+}

src/ErrorsWithPath.php

@@ -0,0 +1,117 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Chubbyphp\Parsing;
+
+/**
+ * @phpstan-type ErrorAsJson array{code: string, template: string, variables: array<string, mixed>}
+ * @phpstan-type ErrorWithPathJson array{error: ErrorAsJson, path: string}
+ * @phpstan-type ErrorsWithPathJson array<ErrorWithPathJson>
+ * @phpstan-type ApiProblem array{name: string, reason: string, details: non-empty-array<string, mixed>}
+ */
+final class ErrorsWithPath implements \JsonSerializable
+{
+    /**
+     * @var array<ErrorWithPath>
+     */
+    private array $errorsWithPath = [];
+
+    /**
+     * @param array<Error|ErrorWithPath|self> $errors
+     */
+    public function __construct(array $errors, private string $path = '')
+    {
+        foreach ($errors as $error) {
+            $this->addError($error);
+        }
+    }
+
+    public function addError(Error|ErrorWithPath|self $error): self
+    {
+        if ($error instanceof self) {
+            foreach ($error->errorsWithPath as $errorWithPath) {
+                $this->errorsWithPath[] = new ErrorWithPath($errorWithPath->error, $this->mergePath($this->path, $errorWithPath->path));
+            }
+        } elseif ($error instanceof ErrorWithPath) {
+            $this->errorsWithPath[] = new ErrorWithPath($error->error, $this->mergePath($this->path, $error->path));
+        } else {
+            $this->errorsWithPath[] = new ErrorWithPath($error, $this->path);
+        }
+
+        return $this;
+    }
+
+    /**
+     * @return ErrorsWithPathJson
+     */
+    public function jsonSerialize(): array
+    {
+        return array_map(static fn ($errorWithPath) => $errorWithPath->jsonSerialize(), $this->errorsWithPath);
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function toTree(): array
+    {
+        // @var array<string, mixed> $tree
+        return array_reduce(
+            $this->errorsWithPath,
+            static function (array $tree, $errorWithPath): array {
+                $pathParts = explode('.', $errorWithPath->path);
+
+                $current = &$tree;
+                $lastIndex = \count($pathParts) - 1;
+
+                foreach ($pathParts as $i => $pathPart) {
+                    if ($i < $lastIndex) {
+                        $current[$pathPart] ??= [];
+                        $current = &$current[$pathPart];
+
+                        continue;
+                    }
+
+                    $current[$pathPart] = array_merge($current[$pathPart] ?? [], [(string) $errorWithPath->error]);
+                }
+
+                return $tree;
+            },
+            []
+        );
+    }
+
+    /**
+     * @return array<ApiProblem>
+     */
+    public function toApiProblem(): array
+    {
+        return array_map(
+            fn (ErrorWithPath $errorWithPath) => [
+                'name' => $this->pathToName($errorWithPath->path),
+                'reason' => (string) $errorWithPath->error,
+                'details' => [
+                    '_template' => $errorWithPath->error->template,
+                    ...$errorWithPath->error->variables,
+                ],
+            ],
+            $this->errorsWithPath
+        );
+    }
+
+    private function mergePath(string $path, string $existingPath): string
+    {
+        return '' === $path ? $existingPath : $path.'.'.$existingPath;
+    }
+
+    private function pathToName(string $path): string
+    {
+        $pathParts = explode('.', $path);
+
+        return implode('', array_map(
+            static fn (string $pathPart, $i) => 0 === $i ? $pathPart : '['.$pathPart.']',
+            $pathParts,
+            array_keys($pathParts)
+        ));
+    }
+}