From dd716b662aa1149a1987ee117af53f72906d0a9c Mon Sep 17 00:00:00 2001
From: Teoh Han Hui <teohhanhui@gmail.com>
Date: Wed, 3 Feb 2016 15:40:39 +0800
Subject: [PATCH] Add isolateSink and isolateSource to support cyclejs/isolate

Shamelessly copied/adapted from cyclejs/cycle-http-driver
---
 src/index.js  | 23 +++++++++++++++++++++++
 test/index.js | 46 ++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 69 insertions(+)

diff --git a/src/index.js b/src/index.js
index 991729a..9bd6277 100644
--- a/src/index.js
+++ b/src/index.js
@@ -24,6 +24,27 @@ function byUrl (response$$, url) {
     .filter(response$ => getUrl(response$.request) === url)
 }
 
+function isolateSink (request$, scope) {
+  return request$.map(request => {
+    if (typeof request === 'string') {
+      return { url: request, _namespace: [scope] }
+    }
+    request._namespace = request._namespace || []
+    request._namespace.push(scope)
+    return request
+  })
+}
+
+function isolateSource (response$$, scope) {
+  const isolatedResponse$$ = response$$.filter(response$ =>
+    Array.isArray(response$.request._namespace) &&
+    response$.request._namespace.indexOf(scope) !== -1
+  )
+  isolatedResponse$$.isolateSource = isolateSource
+  isolatedResponse$$.isolateSink = isolateSink
+  return isolatedResponse$$
+}
+
 // scheduler option is for testing because Reactive-Extensions/RxJS#976
 export function makeFetchDriver (scheduler) {
   return function fetchDriver (request$) {
@@ -42,6 +63,8 @@ export function makeFetchDriver (scheduler) {
       )
     response$$.byKey = byKey.bind(null, response$$)
     response$$.byUrl = byUrl.bind(null, response$$)
+    response$$.isolateSource = isolateSource
+    response$$.isolateSink = isolateSink
     return response$$
   }
 }
diff --git a/test/index.js b/test/index.js
index fd1e6bf..d93882c 100644
--- a/test/index.js
+++ b/test/index.js
@@ -201,6 +201,52 @@ test('byUrl should support input url', t => {
     )
 })
 
+test('isolateSource and isolateSink should exist on the HTTP Source (response$$)', t => {
+  setup()
+  const fetchDriver = makeFetchDriver()
+  const request$ = new Rx.Subject()
+  const response$$ = fetchDriver(request$)
+  t.ok(typeof response$$.isolateSource === 'function')
+  t.ok(typeof response$$.isolateSink === 'function')
+  t.end()
+})
+
+test('isolateSource and isolateSink should exist on a scoped HTTP Source (response$$)', t => {
+  setup()
+  const fetchDriver = makeFetchDriver()
+  const request$ = new Rx.Subject()
+  const response$$ = fetchDriver(request$)
+  const scopedRequest$ = response$$.isolateSink(request$, 'foo')
+  const scopedResponse$$ = response$$.isolateSource(response$$, 'foo')
+  t.ok(typeof scopedResponse$$.isolateSource === 'function')
+  t.ok(typeof scopedResponse$$.isolateSink === 'function')
+  t.end()
+})
+
+test('isolateSource and isolateSink should hide responses from outside the scope', t => {
+  setup()
+  const fetchDriver = makeFetchDriver()
+  const proxyRequest$ = new Rx.Subject()
+  const response$$ = fetchDriver(proxyRequest$)
+  const request1 = 'http://api.test/resource1'
+  const request2 = 'http://api.test/resource2'
+  const ignoredRequest$ = Rx.Observable.just(request1)
+  const request$ = Rx.Observable.just(request2).delay(10)
+  const scopedRequest$ = response$$.isolateSink(request$, 'foo')
+  const scopedResponse$$ = response$$.isolateSource(response$$, 'foo')
+  scopedResponse$$.subscribe(response$ => {
+    t.equal(typeof response$.request, 'object')
+    t.equal(response$.request.url, request2)
+    response$.subscribe(response => {
+      t.equal(response.status, 200)
+      t.equal(response.data, 'resource2')
+      t.end()
+    })
+  })
+  Rx.Observable.merge(ignoredRequest$, scopedRequest$)
+    .subscribe(proxyRequest$.asObserver())
+})
+
 test('after', t => {
   global.fetch = originalFetch
   t.end()