ts-poet

What is ts-poet?

The ts-poet npm package is a TypeScript code generation library that allows you to programmatically create TypeScript code. It is particularly useful for generating code based on some input data or schema, such as generating TypeScript types from a GraphQL schema or a protobuf definition.

What are ts-poet's main functionalities?

Generating TypeScript Interfaces

This feature allows you to generate TypeScript interfaces programmatically. The code sample demonstrates how to create a 'User' interface with properties 'id', 'name', and 'email'.

const { Code, InterfaceSpec } = require('ts-poet');

const userInterface = InterfaceSpec.create('User')
  .addProperty('id', 'number')
  .addProperty('name', 'string')
  .addProperty('email', 'string');

const code = Code.create(userInterface);
console.log(code.toString());

Generating TypeScript Classes

This feature allows you to generate TypeScript classes programmatically. The code sample demonstrates how to create a 'User' class with properties 'id', 'name', and 'email', and a constructor method.

const { Code, ClassSpec } = require('ts-poet');

const userClass = ClassSpec.create('User')
  .addProperty('id', 'number')
  .addProperty('name', 'string')
  .addProperty('email', 'string')
  .addMethod('constructor', 'constructor(id: number, name: string, email: string) { this.id = id; this.name = name; this.email = email; }');

const code = Code.create(userClass);
console.log(code.toString());

Generating TypeScript Functions

This feature allows you to generate TypeScript functions programmatically. The code sample demonstrates how to create a 'greet' function that takes a 'name' parameter and returns a greeting string.

const { Code, FunctionSpec } = require('ts-poet');

const greetFunction = FunctionSpec.create('greet')
  .addParameter('name', 'string')
  .setReturnType('string')
  .setBody('return `Hello, ${name}!`;');

const code = Code.create(greetFunction);
console.log(code.toString());

Other packages similar to ts-poet

typescript

The 'typescript' package is the official TypeScript compiler and language service. While it does not focus on code generation, it provides the necessary tools to parse, analyze, and transform TypeScript code, which can be used for code generation tasks.

ts-morph

The 'ts-morph' package is a TypeScript compiler API wrapper that simplifies working with the TypeScript AST (Abstract Syntax Tree). It provides a higher-level API for creating, navigating, and manipulating TypeScript code, making it a powerful tool for code generation and transformation tasks.

codegen

The 'codegen' package is a general-purpose code generation library that supports multiple languages, including TypeScript. It provides a flexible API for generating code structures, making it a versatile alternative to ts-poet for various code generation needs.

README

The TS version of this library is still WIP.

The Kotlin readme:

---

TypeScriptPoet

TypeScriptPoet is a Kotlin and Java API for generating .ts source files.

Source file generation can be useful when doing things such as annotation processing or interacting with metadata files (e.g., database schemas, protocol formats). By generating code, you eliminate the need to write boilerplate while also keeping a single source of truth for the metadata.

Example

Here's a HelloWorld file:

import {Observable} from 'rxjs/Observable';
import 'rxjs/add/observable/from';


class Greeter {

  private name: string;

  constructor(private name: string) {
  }

  greet(): Observable<string> {
    return Observable.from(`Hello $name`)}

}

And this is the code to generate it with TypeScriptPoet:

val observableTypeName = TypeName.importedType("@rxjs/Observable")

val testClass = ClassSpec.builder("Greeter")
   .addProperty("name", TypeName.STRING, false, Modifier.PRIVATE)
   .constructor(
      FunctionSpec.constructorBuilder()
         .addParameter("name", TypeName.STRING, false, Modifier.PRIVATE)
         .build()
   )
   .addFunction(
      FunctionSpec.builder("greet")
         .returns(TypeName.parameterizedType(observableTypeName, TypeName.STRING))
         .addCode("return %T.%N(`Hello \$name`)", observableTypeName, SymbolSpec.from("+rxjs/add/observable/from#Observable"))
         .build()
   )
   .build()

val file = FileSpec.builder("Greeter")
   .addClass(testClass)
   .build()

val out = StringWriter()
file.writeTo(out)

The KDoc catalogs the complete TypeScriptPoet API, which is inspired by JavaPoet.

Download

Download the latest .jar or depend via Maven:

<dependency>
  <groupId>io.outfoxx</groupId>
  <artifactId>typescriptpoet</artifactId>
  <version>0.1.0</version>
</dependency>

or Gradle:

compile 'io.outfoxx:typescriptpoet:0.1.0'

Snapshots of the development version are available in Sonatype's snapshots repository.

License

Copyright 2017 Outfox, Inc.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

   http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.