aspida

TypeScript friendly HTTP client wrapper for the browser and node.js.

Features

- Path, URL query, header, body, and response can all specify the type
- FormData / URLSearchParams content can also specify the type
- HTTP client supports axios / fetch / node-fetch

Procedure

1. Reproduce the endpoint directory structure in the "api" directory
1. Export a Type alias named "Methods"
1. Call "aspida" with npm scripts
1. API type definition file "api/\$api.ts" will be generated, so import the application and make an HTTP request

Getting Started

$3

- Using npm:

``sh
$ npm install aspida @aspida/axios axios
`

- Using Yarn:

`sh
$ yarn add aspida @aspida/axios axios
`

$3

`sh
$ mkdir api
`

$3

- GET: /v1/users/?limit={number}
- POST: /v1/users

api/v1/users/index.ts

`ts
import type { DefineMethods } from "aspida";

type User = {
id: number;
name: string;
};

export type Methods = DefineMethods<{
get: {
query?: {
limit: number;
};

resBody: User[];
};

post: {
reqBody: {
name: string;
};

resBody: User;
/**
* reqHeaders(?): ...
* reqFormat: ...
* status: ...
* resHeaders(?): ...
* polymorph: [...]
*/
};
}>;
`

- GET: /v1/users/\${userId}
- PUT: /v1/users/\${userId}

api/v1/users/_userId@number/index.ts

Specify the type of path variable “userId” starting with underscore with “@number”
If not specified with @, the default path variable type is "number | string"

`ts
import type { DefineMethods } from "aspida";

type User = {
id: number;
name: string;
};

export type Methods = DefineMethods<{
get: {
resBody: User;
};

put: {
reqBody: {
name: string;
};

resBody: User;
};
}>;
`

$3

package.json

`json
{
"scripts": {
"api:build": "aspida"
}
}
`

`sh
$ npm run api:build

> api/$api.ts was built successfully.
`

$3

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const userId = 0;
const limit = 10;
const client = api(aspida());

await client.v1.users.post({ body: { name: "taro" } });

const res = await client.v1.users.get({ query: { limit } });
console.log(res);
// req -> GET: /v1/users/?limit=10
// res -> { status: 200, body: [{ id: 0, name: "taro" }], headers: {...} }

const user = await client.v1.users._userId(userId).$get();
console.log(user);
// req -> GET: /v1/users/0
// res -> { id: 0, name: "taro" }
})();
`

$3

- @aspida/axios
- @aspida/fetch
- @aspida/node-fetch

Command Line Interface Options

Options of aspida.config.js

| Option | Type | Default | Description |
| -------------------- | ------------------------------------ | ------- | ----------------------------------------------------- |
| input | string | "api" | Specifies the endpoint type definition root directory |
| baseURL | string | "" | Specify baseURL of the request |
| trailingSlash | boolean | false | Append / to the request URL |
| outputEachDir | boolean | false | Generate $api.ts in each endpoint directory |
| outputMode (>=1.6.0) | "all" \| "normalOnly" \| "aliasOnly" | "all" | Output either get or $get for compression |

Node.js API

`ts
import { version, build, watch } from "aspida/dist/commands";

console.log(version()); // 0.x.y

build();
build("./app/aspida.config.js");
build({ input: "api1" });
build([
{ baseURL: "https://example.com/v1" },
{
input: "api2",
baseURL: "https://example.com/v2",
trailingSlash: true,
outputEachDir: true,
outputMode: "all",
},
]);

watch();
watch("./app/aspida.config.js");
watch({ input: "api1" });
watch([
{ baseURL: "https://example.com/v1" },
{
input: "api2",
baseURL: "https://example.com/v2",
trailingSlash: true,
outputEachDir: true,
outputMode: "all",
},
]);
`

Ecosystem

- openapi2aspida - Convert OpenAPI 3.0 and Swagger 2.0 definitions
- aspida-mock - TypeScript friendly RESTful API mock
- frourio - Fast and type-safe full stack framework, for TypeScript TypeScript
- @aspida/react-query - React Query wrapper
- @aspida/swr - SWR (React Hooks) wrapper
- @aspida/swrv - SWRV (Vue Composition API) wrapper
- eslint-plugin-aspida - Support writing aspida api definition

Tips

1. Change the directory where type definition file is placed to other than "api"
1. Serialize GET parameters manually
1. POST with FormData
1. POST with URLSearchParams
1. Receive response with ArrayBuffer
1. Define polymorphic request
1. Define endpoints that contain special characters
1. Import only some endpoints
1. Retrieve endpoint URL string
1. Reflect TSDoc comments

$3

Create a configuration file at the root of the project

aspida.config.js

`javascript
module.exports = { input: "src" };
`

Specify baseURL in configuration file

`javascript
module.exports = { baseURL: "https://example.com/api" };
`

If you want to define multiple API endpoints, specify them in an array

`javascript
module.exports = [{ input: "api1" }, { input: "api2", baseURL: "https://example.com/api" }];
`

$3

aspida leaves GET parameter serialization to standard HTTP client behavior
If you want to serialize manually, you can use config object of HTTP client

src/index.ts

`ts
import axios from "axios";
import qs from "qs";
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(
aspida(axios, { paramsSerializer: params => qs.stringify(params, { indices: false }) })
);

const users = await client.v1.users.$get({
// config: { paramsSerializer: (params) => qs.stringify(params, { indices: false }) },
query: { ids: [1, 2, 3] },
});
console.log(users);
// req -> GET: /v1/users/?ids=1&ids=2&ids=3
// res -> [{ id: 1, name: "taro1" }, { id: 2, name: "taro2" }, { id: 3, name: "taro3" }]
})();
`

$3

api/v1/users/index.ts

`ts
import type { DefineMethods } from "aspida";
import type { ReadStream } from "fs";

export type Methods = DefineMethods<{
post: {
reqFormat: FormData;

reqBody: {
name: string;
icon: File | ReadStream;
};

resBody: {
id: number;
name: string;
};
};
}>;
`

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());

const user = await client.v1.users.$post({
body: {
name: "taro",
icon: imageFile,
},
});
console.log(user);
// req -> POST: h/v1/users
// res -> { id: 0, name: "taro" }
})();
`

Post in Node.js (>=1.6.0)

src/index.ts

`ts
import fs from "fs";
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());
const fileName = "images/sample.jpg";
const user = await client.v1.users.$post({
body: {
name: "taro",
icon: fs.createReadStream(fileName),
},
});
console.log(user);
// req -> POST: h/v1/users
// res -> { id: 0, name: "taro" }
})();
`

$3

api/v1/users/index.ts

`ts
import type { DefineMethods } from "aspida";

export type Methods = DefineMethods<{
post: {
reqFormat: URLSearchParams;

reqBody: {
name: string;
};

resBody: {
id: number;
name: string;
};
};
}>;
`

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());

const user = await client.v1.users.$post({ body: { name: "taro" } });
console.log(user);
// req -> POST: /v1/users
// res -> { id: 0, name: "taro" }
})();
`

$3

api/v1/users/index.ts

`ts
import type { DefineMethods } from "aspida";

export type Methods = DefineMethods<{
get: {
query: {
name: string;
};

resBody: ArrayBuffer;
};
}>;
`

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());

const user = await client.v1.users.$get({ query: { name: "taro" } });
console.log(user);
// req -> GET: /v1/users/?name=taro
// res -> ArrayBuffer
})();
`

$3

api/users/index.ts

`ts
type User = {
id: number;
name: string;
};

export interface Methods {
post: {
// common properties
reqFormat: FormData;
/**
* query(?): ...
* reqHeaders(?): ...
* reqBody(?): ...
* status: ...
* resHeaders(?): ...
* resBody(?): ...
*/
polymorph: [
// polymorphic types
{
reqBody: Omit;
resBody: User;
/**
* query(?): ...
* reqHeaders(?): ...
* status: ...
* resHeaders(?): ...
*/
},
{
reqBody: Omit[];
resBody: User[];
}
];
};
}
`

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());

const user = await client.users.$post({ body: { name: "taro" } });
console.log(user); // { id: 0, name: "taro" }

const users = await client.users.$post({
body: [{ name: "hanako" }, { name: "mario" }],
});
console.log(users); // [{ id: 1, name: "hanako" }, { id: 2, name: "mario" }]
})();
`

$3

Special characters are encoded as percent-encoding in the file name
Example ":" -> "%3A"

api/foo%3Abar/index.ts

`ts
import type { DefineMethods } from "aspida";

export type Methods = DefineMethods<{
get: {
resBody: string;
};
}>;
`

api/users/_userId@number%3Aread/index.ts

`ts
import type { DefineMethods } from "aspida";

export type Methods = DefineMethods<{
get: {
resBody: User;
};
}>;
`

With clients, "%3A" -> ":"

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());

const message = await client.foo_bar.$get();
console.log(message);
// req -> GET: /foo:bar

const user = await client.users._userId_read(1).$get();
console.log(user);
// req -> GET: /users/1:read
})();
`

$3

If you don't need to use all of api/$api.ts , you can split them up and import only part of them
outputEachDir option generates $api.ts in each endpoint directory
$api.ts will not be generated under the directory containing the path variable

aspida.config.js

`js
module.exports = { outputEachDir: true };
`

Import only $api.ts of the endpoint you want to use and put it into Object

src/index.ts

`ts
import aspida from "@aspida/axios";
import api0 from "../api/v1/foo/$api";
import api1 from "../api/v2/bar/$api";
(async () => {
const aspidaClient = aspida();
const client = {
foo: api0(aspidaClient),
bar: api1(aspidaClient),
};

const message = await client.bar._id(1).$get();
// req -> GET: /v2/bar/1
})();
`

$3

src/index.ts

`ts
import aspida from "@aspida/axios";
import api from "../api/$api";
(async () => {
const client = api(aspida());

console.log(client.v1.users.$path());
// /v1/users

console.log(client.vi.users.$path({ query: { limit: 10 } }));
// /v1/users?limit=10

console.log(
client.vi.users.$path({
method: "post",
query: { id: 1 },
})
);
// /v1/users?id=1
})();
`

$3

api/index.ts

`ts
import type { DefineMethods } from "aspida";

/**
* root comment
*
* @remarks
* root remarks comment
*/
export type Methods = DefineMethods<{
/**
* post method comment
*
* @remarks
* post method remarks comment
*/
post: {
/* post query comment /
query: { limit: number };

/* post reqHeaders comment /
reqHeaders: { token: string };

reqFormat: FormData;
/* post reqBody comment /
reqBody: UserCreation;

/**
* post resBody comment1
* post resBody comment2
*/
resBody: User;
};
}>;
`

`sh
$ npm run api:build
`

api/$api.ts

`ts
/**
* root comment
*
* @remarks
* root remarks comment
*/
const api = ({ baseURL, fetch }: AspidaClient) => {
return {
/**
* post method comment
*
* @remarks
* post method remarks comment
*
* @param option.query - post query comment
* @param option.headers - post reqHeaders comment
* @param option.body - post reqBody comment
* @returns post resBody comment1
* post resBody comment2
*/
$post: (option: {
body: Methods0["post"]["reqBody"];
query: Methods0["post"]["query"];
headers: Methods0["post"]["reqHeaders"];
config?: T;
}) =>
fetch(prefix, PATH0, POST, option)
.json()
.then(r => r.body),
};
};
``

License

aspida is licensed under a MIT License.