openapi-to-typescript

1# OpenAPI to TypeScript
2 
3Converts OpenAPI 3.0 specifications to TypeScript interfaces and type guards.
4 
5**Input:** OpenAPI file (JSON or YAML)
6**Output:** TypeScript file with interfaces and type guards
7 
8## When to Use
9 
10- "generate types from openapi"
11- "convert openapi to typescript"
12- "create API interfaces"
13- "generate types from spec"
14 
15## Workflow
16 
171. Request the OpenAPI file path (if not provided)
182. Read and validate the file (must be OpenAPI 3.0.x)
193. Extract schemas from `components/schemas`
204. Extract endpoints from `paths` (request/response types)
215. Generate TypeScript (interfaces + type guards)
226. Ask where to save (default: `types/api.ts` in current directory)
237. Write the file
24 
25## OpenAPI Validation
26 
27Check before processing:
28 
29```
30- Field "openapi" must exist and start with "3.0"
31- Field "paths" must exist
32- Field "components.schemas" must exist (if there are types)
33```
34 
35If invalid, report the error and stop.
36 
37## Type Mapping
38 
39### Primitives
40 
41| OpenAPI     | TypeScript   |
42|-------------|--------------|
43| `string`    | `string`     |
44| `number`    | `number`     |
45| `integer`   | `number`     |
46| `boolean`   | `boolean`    |
47| `null`      | `null`       |
48 
49### Format Modifiers
50 
51| Format        | TypeScript              |
52|---------------|-------------------------|
53| `uuid`        | `string` (comment UUID) |
54| `date`        | `string` (comment date) |
55| `date-time`   | `string` (comment ISO)  |
56| `email`       | `string` (comment email)|
57…