Add support for requestInterceptor / responseInterceptor.

- Display mutated requests from request interceptor in curl output in UI.
  Put this behind showMutatedRequest flag so that the mutation can be
  silent.
- Document requestInterceptor, responseInterceptor and showMutatedRequest
  in README.md
- Add tests

src/core/plugins/spec/actions.js

@@ -12,6 +12,7 @@ export const UPDATE_PARAM = "spec_update_param"
 export const VALIDATE_PARAMS = "spec_validate_param"
 export const SET_RESPONSE = "spec_set_response"
 export const SET_REQUEST = "spec_set_request"
+export const SET_MUTATED_REQUEST = "spec_set_mutated_request"
 export const LOG_REQUEST = "spec_log_request"
 export const CLEAR_RESPONSE = "spec_clear_response"
 export const CLEAR_REQUEST = "spec_clear_request"
@@ -177,6 +178,13 @@ export const setRequest = ( path, method, req ) => {
   }
 }
 
+export const setMutatedRequest = ( path, method, req ) => {
+  return {
+    payload: { path, method, req },
+    type: SET_MUTATED_REQUEST
+  }
+}
+
 // This is for debugging, remove this comment if you depend on this action
 export const logRequest = (req) => {
   return {
@@ -187,8 +195,9 @@ export const logRequest = (req) => {
 
 // Actually fire the request via fn.execute
 // (For debugging) and ease of testing
-export const executeRequest = (req) => ({fn, specActions, specSelectors}) => {
+export const executeRequest = (req) => ({fn, specActions, specSelectors, getConfigs}) => {
   let { pathName, method, operation } = req
+  let { requestInterceptor, responseInterceptor } = getConfigs()
 
   let op = operation.toJS()
 
@@ -207,6 +216,16 @@ export const executeRequest = (req) => ({fn, specActions, specSelectors}) => {
 
   specActions.setRequest(req.pathName, req.method, parsedRequest)
 
+  let requestInterceptorWrapper = function(r) {
+    let mutatedRequest = requestInterceptor.apply(this, [r])
+    let parsedMutatedRequest = Object.assign({}, mutatedRequest)
+    specActions.setMutatedRequest(req.pathName, req.method, parsedMutatedRequest)
+    return mutatedRequest
+  }
+
+  req.requestInterceptor = requestInterceptorWrapper
+  req.responseInterceptor = responseInterceptor
+
   // track duration of request
   const startTime = Date.now()
 

src/core/plugins/spec/reducers.js

@@ -3,13 +3,14 @@ import { fromJSOrdered, validateParam } from "core/utils"
 import win from "../../window"
 
 import {
-	UPDATE_SPEC,
+  UPDATE_SPEC,
   UPDATE_URL,
   UPDATE_JSON,
   UPDATE_PARAM,
   VALIDATE_PARAMS,
   SET_RESPONSE,
   SET_REQUEST,
+  SET_MUTATED_REQUEST,
   UPDATE_RESOLVED,
   UPDATE_OPERATION_VALUE,
   CLEAR_RESPONSE,
@@ -101,6 +102,10 @@ export default {
     return state.setIn( [ "requests", path, method ], fromJSOrdered(req))
   },
 
+  [SET_MUTATED_REQUEST]: (state, { payload: { req, path, method } } ) =>{
+    return state.setIn( [ "mutatedRequests", path, method ], fromJSOrdered(req))
+  },
+
   [UPDATE_OPERATION_VALUE]: (state, { payload: { path, value, key } }) => {
     let operationPath = ["resolved", "paths", ...path]
     if(!state.getIn(operationPath)) {

src/core/plugins/spec/selectors.js

@@ -237,6 +237,11 @@ export const requests = createSelector(
     state => state.get( "requests", Map() )
 )
 
+export const mutatedRequests = createSelector(
+    state,
+    state => state.get( "mutatedRequests", Map() )
+)
+
 export const responseFor = (state, path, method) => {
   return responses(state).getIn([path, method], null)
 }
@@ -245,6 +250,10 @@ export const requestFor = (state, path, method) => {
   return requests(state).getIn([path, method], null)
 }
 
+export const mutatedRequestFor = (state, path, method) => {
+  return mutatedRequests(state).getIn([path, method], null)
+}
+
 export const allowTryItOutFor = () => {
   // This is just a hook for now.
   return true