From f8d475cb53d64c153fadde74bd40ad137e9bcf97 Mon Sep 17 00:00:00 2001
From: peter <peter.millauer@gmail.com>
Date: Thu, 5 Mar 2020 18:14:40 +0100
Subject: [PATCH] sesamefilter

---
 src/Backend.ts  | 17 ++++++++++++-----
 src/Frontend.ts |  6 +++---
 src/Types.ts    |  5 +++--
 test/Test.ts    | 29 +++++++++++++++++++++++++----
 4 files changed, 43 insertions(+), 14 deletions(-)

diff --git a/src/Backend.ts b/src/Backend.ts
index 9d18900..b707258 100644
--- a/src/Backend.ts
+++ b/src/Backend.ts
@@ -25,6 +25,7 @@ export class RPCServer<
     private errorHandler: T.ErrorHandler
     private connectionHandler: T.ConnectionHandler
     private sesame? : T.SesameFunction
+    private accessFilter: T.AccessFilter<InterfaceT, SubResType>
 
     /**
      * @throws On RPC with no name
@@ -35,10 +36,12 @@ export class RPCServer<
     constructor(
         private port:number,
         private exporters: Exporters<InterfaceT, SubResType> = [],
-        conf: T.ServerConf =  {}
+        conf: T.ServerConf<InterfaceT, SubResType> =  {}
     ){
         if(!conf.visibility) this.visibility = "127.0.0.1"        
         
+        this.accessFilter = conf.accessFilter || (async () => true)
+
         if(conf.sesame){
             this.sesame = U.makeSesameFunction(conf.sesame)
         }
@@ -87,10 +90,14 @@ export class RPCServer<
     }
 
     protected initRPCs(socket:I.Socket){
-        socket.hook('info', () => rpcInfos)
-        const rpcInfos:T.ExtendedRpcInfo[] = [
-            ...this.exporters.flatMap(exporter => U.rpcHooker(socket, exporter, this.errorHandler, this.sesame))
-        ]
+        socket.hook('info', async (sesame? : string) => {
+            const rpcs = await Promise.all(this.exporters.map(async exp => {
+                const allowed = await this.accessFilter(sesame, exp)
+                if(!allowed) return []
+                return U.rpcHooker(socket, exp, this.errorHandler, this.sesame)
+            }))
+            return rpcs.flat()
+        })
     }
 
     /**
diff --git a/src/Frontend.ts b/src/Frontend.ts
index 2401e2a..30f8dc8 100644
--- a/src/Frontend.ts
+++ b/src/Frontend.ts
@@ -136,7 +136,7 @@ export class RPCSocket implements I.Socket{
             this.socket.hook(kv[0], kv[1])
         })
 
-        const info:T.ExtendedRpcInfo[] = await this.info()
+        const info:T.ExtendedRpcInfo[] = await this.info(sesame)
         info.forEach(i => {
             let f: any
             
@@ -159,9 +159,9 @@ export class RPCSocket implements I.Socket{
     /**
      * Get a list of available RPCs from the server
      */
-    public async info(){
+    public async info(sesame?:string){
         if(!this.socket) throw new Error("The socket is not connected! Use socket.connect() first")
-        return await this.socket.call('info')
+        return await this.socket.call('info', sesame)
     }
 
     /**
diff --git a/src/Types.ts b/src/Types.ts
index 3296e6e..f57213a 100644
--- a/src/Types.ts
+++ b/src/Types.ts
@@ -2,7 +2,7 @@ import * as I from "./Interfaces";
 
 export type AnyFunction = (...args:any) => any
 export type HookFunction<F extends AnyFunction = AnyFunction, SubresT = {}> = (...args: Parameters<F>) => Promise<SubscriptionResponse<SubresT> | ErrorResponse>
-
+export type AccessFilter<InterfaceT extends RPCInterface, SubresT> = (sesame:string|undefined, exporter: I.RPCExporter<RPCInterface<InterfaceT>, keyof InterfaceT, SubresT>) => Promise<boolean> 
 export type Visibility = "127.0.0.1" | "0.0.0.0"
 export type ConnectionHandler = (socket:I.Socket) => void
 export type ErrorHandler = (socket:I.Socket, error:any, rpcName: string, args: any[]) => void
@@ -17,7 +17,8 @@ export type FrontEndHandlerType = {
     'close' : () => void
 }
 
-export type ServerConf = {
+export type ServerConf<InterfaceT extends RPCInterface, SubresT> = {
+    accessFilter?: AccessFilter<InterfaceT, SubresT>
     connectionHandler?: ConnectionHandler
     errorHandler?: ErrorHandler
     closeHandler?: CloseHandler
diff --git a/test/Test.ts b/test/Test.ts
index 8b2ce54..c51984c 100644
--- a/test/Test.ts
+++ b/test/Test.ts
@@ -542,8 +542,9 @@ type myExporterIfc = {
 describe("Class binding", ()=>{
 
     let exporter1 : MyExporter
-    let serv : RPCServer
+    let serv : RPCServer<{}, myExporterIfc>
     let sock: RPCSocket & myExporterIfc
+    let allowed = true
 
     class MyExporter implements RPCExporter<myExporterIfc>{
         name = "MyExporter" as "MyExporter";
@@ -563,20 +564,34 @@ describe("Class binding", ()=>{
             this.myRPC
         ]
 
-        myRPC = async () => "Hello Borld"
+        myRPC = async () => { 
+            return "Hello Borld"
+        }
 
     }
 
     before(done => {
         exporter1 = new MyExporter()
-        serv = new RPCServer(21004, [exporter1])
+        serv = new RPCServer<{}, myExporterIfc>(21004, [exporter1], {
+            accessFilter: async (sesame,exporter) => {
+                switch(exporter.name){
+                    case "MyExporter": 
+                        if(!allowed) return false
+                        allowed = false
+                        return sesame==='xxx';
+                    default:
+                        return false
+                }
+            },
+            sesame: "xxx"
+        })
         done()
     })
         
     beforeEach((done)=>{
         
         const s = new RPCSocket(21004, 'localhost')
-        s.connect<myExporterIfc>().then(conn => {
+        s.connect<myExporterIfc>("xxx").then(conn => {
             sock = conn
             done()
         })
@@ -596,6 +611,7 @@ describe("Class binding", ()=>{
             done(new Error(res))
         }).catch(e => {
             //job will time out because of setExporters
+            allowed = true
             done()
         })
     })
@@ -608,6 +624,11 @@ describe("Class binding", ()=>{
                 done(new Error(res))
         })
     })
+
+    it("use sesameFilter", (done) => {
+        if(!sock['MyExporter']) done()
+        else done(new Error("RPC supposed to be gone"))
+    })
 })