✨ feat: implement core Optimus library for JSON mapping and validation

- 🎨 add Spring-like decorators (@JsonSerialize, @JsonDeserialize, etc.) - ⚙️ implement JsonMapper and metadata storage for transformations - 🧪 add comprehensive test suite using Vitest - 📝 add README, CONTRIBUTING, and API documentation - 👷 setup GitHub Actions CI workflow - 🔧 configure TypeScript and project settings
2026-04-11 16:58:12 +02:00
parent 45e790a7d0
commit 7fe7e8c7c3
15 changed files with 2026 additions and 19 deletions
@@ -0,0 +1,176 @@
+import { 
+  IsString, 
+  IsInt, 
+  Min, 
+  ValidateNested, 
+  IsArray, 
+  IsDate,
+  JsonSerialize, 
+  JsonDeserialize, 
+  JsonPolymorphic, 
+  JsonMapper, 
+  JsonSerializer, 
+  JsonDeserializer,
+  Validate,
+  ValidatorConstraintInterface,
+  ValidationArguments,
+  registerDecorator,
+  ValidationOptions
+} from './index';
+
+// --- Custom Validators ---
+
+class IsLongerThan implements ValidatorConstraintInterface {
+  validate(value: any, args: ValidationArguments): boolean {
+    const minLength = args.constraints[0];
+    return typeof value === 'string' && value.length > minLength;
+  }
+
+  defaultMessage(args: ValidationArguments): string {
+    return `${args.property} must be longer than ${args.constraints[0]} characters (actual: ${args.value?.length})`;
+  }
+}
+
+function IsUsername(options?: ValidationOptions) {
+  return function (object: any, propertyName: string) {
+    registerDecorator({
+      name: 'isUsername',
+      target: object.constructor,
+      propertyName: propertyName,
+      ...(options ? { options } : {}),
+      validator: (value: any) => typeof value === 'string' && /^[a-zA-Z0-9_]+$/.test(value)
+    });
+  };
+}
+
+// --- Custom Serializers ---
+
+class DateSerializer implements JsonSerializer<Date, string> {
+  serialize(value: Date): string {
+    if (value instanceof Date) {
+      return value.toISOString().split('T')[0] || '';
+    }
+    return String(value);
+  }
+}
+
+class DateDeserializer implements JsonDeserializer<string, Date> {
+  deserialize(value: string): Date {
+    return new Date(value);
+  }
+}
+
+// --- Domain Models ---
+
+abstract class Media {
+  @IsString()
+  abstract type: string;
+
+  @IsString()
+  title: string;
+}
+
+class Book extends Media {
+  @IsString()
+  override type: string = 'book';
+
+  @IsString()
+  @IsUsername({ message: 'Title must be a valid alphanumeric username' })
+  override title: string;
+
+  @IsString()
+  @Validate(IsLongerThan, [5])
+  author: string;
+
+  @JsonSerialize(DateSerializer)
+  @JsonDeserialize(DateDeserializer)
+  @IsDate()
+  publishedAt: Date;
+}
+
+class Movie extends Media {
+  @IsString()
+  type: string = 'movie';
+
+  @IsInt()
+  @Min(1)
+  duration: number;
+}
+
+class Library {
+  @IsString()
+  name: string;
+
+  @IsArray()
+  @ValidateNested()
+  @JsonPolymorphic('type', [
+    { value: Book, name: 'book' },
+    { value: Movie, name: 'movie' }
+  ])
+  items: Media[];
+}
+
+// --- Execution ---
+
+async function runExample() {
+  console.log("--- Starting Example ---");
+
+  // 1. Create a Library instance
+  const library = new Library();
+  library.name = "Central Library";
+  
+  const book = new Book();
+  book.title = "Gatsby";
+  book.author = "Fitzgerald";
+  book.publishedAt = new Date("1925-04-10");
+
+  const movie = new Movie();
+  movie.title = "Inception";
+  movie.duration = 148;
+
+  library.items = [book, movie];
+
+  try {
+    // 2. Serialize to JSON
+    console.log("\n[1] Serializing Library to JSON...");
+    const json = await JsonMapper.toJson(library);
+    console.log("JSON Output:", json);
+
+    // 3. Deserialize back to Instance
+    console.log("\n[2] Deserializing JSON back to Library instance...");
+    const deserializedLibrary = await JsonMapper.fromJson(Library, json);
+    console.log("Deserialized Library Name:", deserializedLibrary.name);
+    console.log("Items count:", deserializedLibrary.items.length);
+
+    // Check Polymorphism
+    deserializedLibrary.items.forEach((item, index) => {
+      console.log(`Item ${index} is instance of ${item.constructor.name}: ${item.title}`);
+      if (item instanceof Book) {
+        console.log(`  > Book Author: ${item.author}`);
+        console.log(`  > Published At: ${item.publishedAt.toISOString()} (instanceof Date: ${item.publishedAt instanceof Date})`);
+      } else if (item instanceof Movie) {
+        console.log(`  > Movie Duration: ${item.duration} mins`);
+      }
+    });
+
+    // 4. Test Validation Failure
+    console.log("\n[3] Testing Validation Failure (Invalid Movie Duration)...");
+    const invalidJson = JSON.stringify({
+      name: "Invalid Library",
+      items: [
+        { type: "movie", title: "Short Film", duration: -5 } // Invalid: duration < 1
+      ]
+    });
+
+    await JsonMapper.fromJson(Library, invalidJson);
+  } catch (error) {
+    if (error instanceof Error) {
+      console.log("Caught expected error:", error.message);
+      if ((error as any).errors) {
+        console.log("Validation details:", JSON.stringify((error as any).errors, null, 2));
+      }
+    }
+  }
+}
+
+runExample();