@pradiptakp-org/openapi-typescript
v5.1.0TypeScript
Generate TypeScript types from Swagger OpenAPI specs
0/weekUpdated 3 years agoMITUnpacked: 204.0 KB
Published by drew@pow.rs
npm install @pradiptakp-org/openapi-typescript
๐๏ธ openapi-typescript
๐ Convert [OpenAPI 3.0][openapi3] and [2.0 (Swagger)][openapi2] schemas to TypeScript interfaces using Node.js.
Features
- โ
[OpenAPI 3.0][openapi3]
- โ
[Swagger 2.0][openapi2]
- โ
Supports YAML and JSON schema formats
- โ
Supports loading via remote URL (simple authentication supported with the --auth flag)
- โ
Supports remote references: $ref: "external.yaml#components/schemas/User"
- โ
Formats using [Prettier][prettier]
- โ
TypeScript 4.0 features
Examples
- Stripe, OpenAPI 2.0
- Stripe, OpenAPI 3.0
Usage
$3
#### ๐๏ธ Reading specs from file system
``bash
npx openapi-typescript schema.yaml --output schema.ts
๐ญ Loading spec from schema.yamlโฆ
๐ schema.yaml -> schema.ts [250ms]
npx openapi-typescript "specs/*/.yaml" --output schemas/
๐ญ Loading spec from specs/one.yamlโฆ
๐ญ Loading spec from specs/two.yamlโฆ
๐ญ Loading spec from specs/three.yamlโฆ
๐ specs/one.yaml -> schemas/specs/one.ts [250ms]
๐ specs/two.yaml -> schemas/specs/two.ts [250ms]
๐ specs/three.yaml -> schemas/specs/three.ts [250ms]
`
_Note: if generating a single schema,
must be a file (preferably *.ts). If using globs, --output must be a directory.__Thanks to @sharmarajdaksh for the glob feature!_
#### โ๏ธ Reading specs from remote resource
`bash
npx openapi-typescript https://petstore.swagger.io/v2/swagger.json --output petstore.ts๐ญ Loading spec from https://petstore.swagger.io/v2/swagger.jsonโฆ
๐ https://petstore.swagger.io/v2/swagger.json -> petstore.ts [650ms]
`_Note: globbing doesnโt work for remote schemas because there is no reliable way to determine a list of files to select from a remote file system._
_Thanks to @psmyrdek for the remote spec feature!_
#### Using in TypeScript
Import any top-level item from the generated spec to use it. It works best if you also alias types to save on typing:
ts
import { components } from "./generated-schema.ts";type APIResponse = components["schemas"]["APIResponse"];
`Because OpenAPI schemas may have invalid TypeScript characters as names, the square brackets are a safe way to access every property.
Also note that thereโs a special
interface that you can import OperationObjects by their [operationId][openapi-operationid]:`ts
import { operations } from "./generated-schema.ts";type getUsersById = operations["getUsersById"];
`Even though
isnโt present in your original schema, itโs a simple convenience and wonโt disrupt any of your other types._Thanks to @gr2m for the operations feature!_
#### openapi-typescript-fetch
The generated spec can also be used with openapi-typescript-fetch which implements a typed fetch client for openapi-typescript.
`ts
import { paths } from "./petstore";import { Fetcher } from "openapi-typescript-fetch";
// declare fetcher for paths
const fetcher = Fetcher.for()
// global configuration
fetcher.configure({
baseUrl: "https://petstore.swagger.io/v2",
init: {
headers: {
...
},
},
use: [...] // middlewares
})
// create fetch operations
const findPetsByStatus = fetcher.path("/pet/findByStatus").method("get").create()
const addPet = fetcher.path("/pet").method("post").create()
// fetch
try {
const { status, data: pets } = await findPetsByStatus({
status: ["available", "pending"],
})
await addPet({ ... })
} catch(e) {
// check which operation threw the exception
if (e instanceof addPet.Error) {
// get discriminated union { status, data }
const error = e.getActualType()
if (error.status === 400) {
error.data.validationErrors // 400 response data
} else if (error.status === 500) {
error.data.errorMessage // 500 response data
} else {
...
}
}
}
`#### Outputting to stdout
Simply omit the
flag to return to stdout:`bash
npx openapi-typescript schema.yaml
`#### CLI Options
| Option | Alias | Default | Description |
| :----------------------------- | :---- | :------: | :-------------------------------------------------------------------------------------------------------------------------------------- |
|
| -o | (stdout) | Where should the output file be saved? |
| --auth [token] | | | (optional) Provide an auth token to be passed along in the request (only if accessing a private schema) |
| --immutable-types | -it | false | (optional) Generates immutable types (readonly properties and readonly array) |
| --additional-properties | -ap | false | (optional) Allow arbitrary properties for all schema objects without additionalProperties: false |
| --default-non-nullable | | false | (optional) Treat schema objects with default values as non-nullable |
| --prettier-config [location] | -c | | (optional) Path to your custom Prettier configuration for output |
| --raw-schema | | false | Generate TS types from partial schema (e.g. having components.schema at the top level) |
| --httpMethod | -m | GET | (optional) Provide the HTTP Verb/Method for fetching a schema from a remote URL |
| --headersObject | -h | | (optional) Provide a JSON object as string of HTTP headers for remote schema request. This will take priority over --header |
| --header | -x | | (optional) Provide an array of or singular headers as an alternative to a JSON object. Each header must follow the key: value pattern |$3
`bash
npm i --save-dev openapi-typescript
`js
import fs from "fs";
import openapiTS from "openapi-typescript";// example 1: load [object] as schema (JSON only)
const schema = await fs.promises.readFile("spec.json", "utf8") // must be OpenAPI JSON
const output = await openapiTS(JSON.parse(schema));
// example 2: load [string] as local file (YAML or JSON; released in v4.0)
const localPath = new URL("./spec.yaml", import.meta.url); // may be YAML or JSON format
const output = await openapiTS(localPath);
// example 3: load [string] as remote URL (YAML or JSON; released in v4.0)
const output = await openapiTS("https://myurl.com/v1/openapi.yaml");
`The Node API may be useful if dealing with dynamically-created schemas, or youโre using within context of a larger application. Pass in either a JSON-friendly object to load a schema from memory, or a string to load a schema from a local file or remote URL (it will load the file quickly using built-in Node methods). Note that a YAML string isnโt supported in the Node.js API; either use the CLI or convert to JSON using [js-yaml][js-yaml] first.
โ ๏ธ As of
, openapiTS() is an async function.#### Custom Formatter
If using the Node.js API, you can optionally pass a formatter to openapi-typescript. This is useful if you want to override the default types and substitute your own.
For example, say your schema has the following property:
`yaml
properties:
updated_at:
type: string
format: date-time
`By default, this will generate a type
. But we can override this by passing a formatter to the Node API, like so:`js
const types = openapiTS(mySchema, {
formatter(node: SchemaObject) {
if (node.format === "date-time") {
return "Date"; // return the TypeScript โDateโ type, as a string
}
// for all other schema objects, let openapi-typescript decide (return undefined)
});
`This will generate
instead. Note that you will still have to do the parsing of your data yourself. But this will save you from having to also update all your types._Note: you donโt have to use
.formatโthis is just an example! You can use any property on a schema object to overwrite its generated type if desired._๐
Project Goals
1. Support converting any OpenAPI 3.0 or 2.0 (Swagger) schema to TypeScript types, no matter how complicated
1. The generated TypeScript types must match your schema as closely as possible (i.e. donโt convert names to
PascalCase` or follow any TypeScript-isms; faithfully reproduce your schema as closely as possible, capitalizationand all)
1. This library is a TypeScript generator, not a schema validator.
๐ค Contributing
PRs are welcome! Please see our CONTRIBUTING.md guide. Opening an issue beforehand to discuss is
encouraged but not required.
[glob]: https://www.npmjs.com/package/glob
[js-yaml]: https://www.npmjs.com/package/js-yaml
[namespace]: https://www.typescriptlang.org/docs/handbook/namespaces.html
[npm-run-all]: https://www.npmjs.com/package/npm-run-all
[openapi-format]: https://swagger.io/specification/#data-types
[openapi-operationid]: https://swagger.io/specification/#operation-object
[openapi2]: https://swagger.io/specification/v2/
[openapi3]: https://swagger.io/specification
[prettier]: https://npmjs.com/prettier
$3
Thanks goes to these wonderful people (emoji key):
This project follows the all-contributors specification.
Contributions of any kind welcome!