in with the new

src/core/plugins/download-url.js

@@ -0,0 +1,67 @@
+/* global Promise */
+
+import { createSelector } from "reselect"
+import { Map } from "immutable"
+
+export default function downloadUrlPlugin (toolbox) {
+  let { fn, Im } = toolbox
+
+  const actions = {
+    download: (url)=> ({ errActions, specSelectors, specActions }) => {
+      let { fetch } = fn
+      url = url || specSelectors.url()
+      specActions.updateLoadingStatus("loading")
+      fetch(url, {
+        headers: {
+          "Accept": "application/json"
+        }
+      }).then(next,next)
+
+      function next(res) {
+        if(res instanceof Error || res.status >= 400) {
+          specActions.updateLoadingStatus("failed")
+          return errActions.newThrownErr( new Error(res.statusText + " " + url) )
+        }
+        specActions.updateLoadingStatus("success")
+        specActions.updateSpec(res.text)
+        specActions.updateUrl(url)
+      }
+
+    },
+
+    updateLoadingStatus: (status) => {
+      let enums = [null, "loading", "failed", "success"]
+      if(enums.indexOf(status) === -1) {
+        console.error(`Error: ${status} is not one of ${JSON.stringify(enums)}`)
+      }
+
+      return {
+        type: "spec_update_loading_status",
+        payload: status
+      }
+    }
+  }
+
+  let reducers = {
+    "spec_update_loading_status": (state, action) => {
+      return (typeof action.payload === "string")
+        ? state.set("loadingStatus", action.payload)
+        : state
+    }
+  }
+
+  let selectors = {
+    loadingStatus: createSelector(
+      state => {
+        return state || Map()
+      },
+      spec => spec.get("loadingStatus") || null
+    )
+  }
+
+  return {
+    statePlugins: {
+      spec: { actions, reducers, selectors }
+    }
+  }
+}