feat: expose FromSchema options (#22)

* feat: expose FromSchema options

* test: add tests for external references

* docs: update to add an example of how to use external references

* Update README.md

* Update README.md

README.md

@@ -34,3 +34,56 @@ const plugin: FastifyPluginAsyncJsonSchemaToTs = async function (
   );
 };
 ```
+
+## Using References from a Shared Schema
+
+JsonSchemaToTsProvider takes a generic that can be passed in the Shared Schema
+as shown in the following example
+
+```ts
+const userSchema = {
+  type: "object",
+  additionalProperties: false,
+  properties: {
+    givenName: { type: "string" },
+    familyName: { type: "string" },
+  },
+  required: ["givenName", "familyName"],
+} as const;
+
+const sharedSchema = {
+  $id: "shared-schema",
+  definitions: {
+    user: userSchema,
+  },
+} as const;
+
+// then when using JsonSchemaToTsProvider, the shared schema is passed through the generic
+// references takes an array so can pass in multiple shared schema
+const fastify =
+  Fastify().withTypeProvider<
+    JsonSchemaToTsProvider<{ references: [typeof sharedSchema] }>
+  >();
+
+// now reference the shared schema like the following
+fastify.get(
+  "/profile",
+  {
+    schema: {
+      body: {
+        type: "object",
+        properties: {
+          user: {
+            $ref: "shared-schema#/definitions/user",
+          },
+        },
+        required: ['user'],
+      },
+    } as const,
+  },
+  (req) => {
+    // givenName and familyName will be correctly typed as strings!
+    const { givenName, familyName } = req.body.user;
+  }
+);
+```

index.ts

@@ -7,10 +7,10 @@ import {
   FastifyPluginAsync
 } from 'fastify'
 
-import { JSONSchema7, FromSchema } from 'json-schema-to-ts'
+import { JSONSchema7, FromSchema, FromSchemaOptions, FromSchemaDefaultOptions } from 'json-schema-to-ts'
 
-export interface JsonSchemaToTsProvider extends FastifyTypeProvider {
-  output: this['input'] extends JSONSchema7 ? FromSchema<this['input']> : never;
+export interface JsonSchemaToTsProvider<Options extends FromSchemaOptions = FromSchemaDefaultOptions> extends FastifyTypeProvider {
+  output: this['input'] extends JSONSchema7 ? FromSchema<this['input'], Options> : never;
 }
 
 /**

types/references.test-d.ts

@@ -0,0 +1,62 @@
+import { JsonSchemaToTsProvider } from '../index'
+import { expectAssignable, expectType } from 'tsd'
+import Fastify, { FastifyInstance, FastifyLoggerInstance, RawReplyDefaultExpression, RawRequestDefaultExpression, RawServerDefault } from 'fastify'
+import { FromSchema } from 'json-schema-to-ts'
+
+const addressSchema = {
+  type: 'object',
+  additionalProperties: false,
+  properties: {
+    line1: { type: 'string' },
+    line2: { type: 'string' },
+    city: { type: 'string' }
+  },
+  required: ['line1', 'city']
+} as const
+type Address = FromSchema<typeof addressSchema>;
+
+const userSchema = {
+  type: 'object',
+  additionalProperties: false,
+  properties: {
+    givenName: { type: 'string' },
+    familyName: { type: 'string' }
+  },
+  required: ['givenName', 'familyName']
+} as const
+type User = FromSchema<typeof userSchema>
+
+const sharedSchema = {
+  $id: 'shared-schema',
+  definitions: {
+    address: addressSchema,
+    user: userSchema
+  }
+} as const
+
+type JsonSchemaToTsProviderWithSharedSchema = JsonSchemaToTsProvider<{
+  references: [typeof sharedSchema];
+}>;
+const fastify = Fastify().withTypeProvider<JsonSchemaToTsProviderWithSharedSchema>()
+
+expectAssignable<FastifyInstance<RawServerDefault, RawRequestDefaultExpression, RawReplyDefaultExpression, FastifyLoggerInstance, JsonSchemaToTsProviderWithSharedSchema>>(fastify)
+
+fastify.get('/profile', {
+  schema: {
+    body: {
+      type: 'object',
+      properties: {
+        user: {
+          $ref: 'shared-schema#/definitions/user'
+        },
+        address: {
+          $ref: 'shared-schema#/definitions/address'
+        }
+      },
+      required: ['user', 'address']
+    } as const
+  }
+}, (req) => {
+  expectType<User>(req.body.user)
+  expectType<Address>(req.body.address)
+})