feat(dandi/http-model): add @RequestHeader decorator to allow injec…

…ting individual request headers

closes #56

_examples/simple-express-rest-api/src/view/view.controller.ts

@@ -1,8 +1,9 @@
 import { Inject } from '@dandi/core'
-import { HttpRequest, HttpRequestQueryParamMap, ParamMap } from '@dandi/http'
+import { HttpRequest, HttpRequestQueryParamMap, ParamMap, HttpHeader } from '@dandi/http'
 import { QueryParam } from '@dandi/http-model'
 import { Controller, HttpGet } from '@dandi/mvc'
 import { View, ViewResult, ViewResultFactory } from '@dandi/mvc-view'
+import { RequestHeader } from '@dandi/http-model/src/request-header.decorator'
 
 @Controller('view')
 export class ViewController {
@@ -52,9 +53,10 @@ export class ViewController {
   public cors(
     @QueryParam(String) restApiHost: string,
     @QueryParam(String) awsHost: string,
+    @RequestHeader(HttpHeader.host) host: string,
     @Inject(HttpRequest) req: HttpRequest,
-  ): { restApiHost: string, restApiPort: number, awsHost: string, search: string, appendSearch: string } {
-    const [, restApiPort] = req.get('host').split(':')
+  ): { restApiHost: string, restApiPort: string, awsHost: string, search: string, appendSearch: string } {
+    const [, restApiPort] = host.split(':')
     const search = [...Object.entries(req.query)].reduce((result, [key, value]) => {
       if (result) {
         result += '&'

packages/dandi/http-model/src/request-header.decorator.spec.ts

@@ -0,0 +1,56 @@
+import { OpinionatedToken } from '@dandi/core'
+import { getInjectableParamMetadata, methodTarget, ParamMetadata } from '@dandi/core/internal/util'
+import { testHarness } from '@dandi/core/testing'
+import {
+  createHttpRequestScope,
+  HttpHeader,
+  HttpRequest,
+  HttpRequestHeadersAccessor,
+  HttpRequestHeadersHashAccessor,
+  MimeType,
+  requestHeaderToken,
+} from '@dandi/http'
+
+import { expect } from 'chai'
+
+import { RequestHeader } from './request-header.decorator'
+
+describe('@RequestHeader', () => {
+  class TestController {
+    // eslint-disable-next-line @typescript-eslint/no-unused-vars
+    public testHeader(@RequestHeader(HttpHeader.contentType) contentType: any): any {}
+  }
+
+  const harness = testHarness()
+
+  let meta: ParamMetadata<any>
+
+  beforeEach(() => {
+    meta = getInjectableParamMetadata(methodTarget(TestController), 'testHeader', 0)
+  })
+  afterEach(() => {
+    meta = undefined
+  })
+
+  it('sets a token for the specified header', async () => {
+    expect(meta).to.exist
+    expect(meta.token).to.exist
+    expect(meta.token).to.be.instanceOf(OpinionatedToken)
+    expect(meta.token).to.equal(requestHeaderToken(HttpHeader.contentType))
+  })
+
+  it('creates a provider to handle injecting the header value', async () => {
+
+    harness.register(...meta.providers, {
+      provide: HttpRequestHeadersAccessor,
+      useValue: HttpRequestHeadersHashAccessor.fromRaw({
+        [HttpHeader.contentType]: MimeType.applicationJson,
+      }),
+    })
+    const injector = harness.createChild(createHttpRequestScope({} as HttpRequest))
+
+    expect(await injector.inject(requestHeaderToken(HttpHeader.contentType))).to.deep.equal({ contentType: MimeType.applicationJson })
+
+  })
+
+})

packages/dandi/http-model/src/request-header.decorator.ts

@@ -0,0 +1,26 @@
+import { MethodTarget } from '@dandi/common'
+import { getInjectableParamMetadata, ParamMetadata } from '@dandi/core/internal/util'
+import {
+  HttpRequestHeader, HttpRequestHeaders,
+  requestHeaderProvider,
+  requestHeaderToken,
+} from '@dandi/http'
+
+export interface RequestHeader<THeaderName extends HttpRequestHeader> extends ParamMetadata<HttpRequestHeaders[THeaderName]> {
+  headerName: THeaderName
+}
+
+export function requestHeaderDecorator<THeaderName extends HttpRequestHeader>(
+  header: RequestHeader<THeaderName>,
+  target: MethodTarget<HttpRequestHeaders[THeaderName]>,
+  propertyName: string,
+  paramIndex: number,
+): void {
+  const meta = getInjectableParamMetadata<HttpRequestHeaders[THeaderName], RequestHeader<THeaderName>>(target, propertyName, paramIndex)
+  meta.token = requestHeaderToken<THeaderName>(header.headerName)
+  meta.providers = [requestHeaderProvider(header.headerName)]
+}
+
+export function RequestHeader<THeaderName extends HttpRequestHeader, TTarget>(headerName: THeaderName): ParameterDecorator {
+  return requestHeaderDecorator.bind(null, { headerName })
+}