Simplify /oauth2/issue logic

package.json

@@ -1,6 +1,6 @@
 {
   "name": "@extollo/lib",
-  "version": "0.9.37",
+  "version": "0.9.38",
   "description": "The framework library that lifts up your code.",
   "main": "lib/index.js",
   "types": "lib/index.d.ts",

src/auth/server/OAuth2Server.ts

@@ -13,7 +13,7 @@ import {
     TokenRepository,
 } from './types'
 import {HTTPError} from '../../http/HTTPError'
-import {Awaitable, HTTPStatus, Maybe, right} from '../../util'
+import {HTTPStatus, Maybe} from '../../util'
 import {view} from '../../http/response/ViewResponseFactory'
 import {SecurityContext} from '../context/SecurityContext'
 import {redirect} from '../../http/response/RedirectResponseFactory'
@@ -50,14 +50,13 @@ export class OAuth2Server extends Controller {
 
         Route.post('/oauth2/token')
             .alias('@oauth2:token')
-            .parameterMiddleware<OAuth2Client>(async req =>
-                right(await req.make<OAuth2Server>(OAuth2Server).getClientFromRequest(req)))
             .passingRequest()
             .calls<OAuth2Server>(OAuth2Server, x => x.issue)
     }
 
-    issue(request: Request, client: OAuth2Client): Awaitable<ResponseObject> {
+    async issue(request: Request): Promise<ResponseObject> {
         const grant = request.safe('grant_type').in(grantTypes)
+        const client = await this.getClientFromRequest(request)
 
         if ( grant === GrantType.Client ) {
             return this.issueFromClient(request, client)