feat(app, app-shell): add ability to disable discovery cache

app-shell/src/discovery.js

@@ -33,6 +33,7 @@ export function registerDiscovery(dispatch: Dispatch) {
 
   config = getConfig('discovery')
   store = new Store({ name: 'discovery', defaults: { services: [] } })
+  let disableCache = config.disableCache
 
   client = createDiscoveryClient({
     pollInterval: SLOW_POLL_INTERVAL_MS,
@@ -51,6 +52,10 @@ export function registerDiscovery(dispatch: Dispatch) {
     client.setCandidates(['[fd00:0:cafe:fefe::1]'].concat(value))
   )
 
+  handleConfigChange('discovery.disableCache', value => {
+    disableCache = value
+  })
+
   app.once('will-quit', () => client.stop())
 
   return function handleIncomingAction(action: Action) {
@@ -73,7 +78,9 @@ export function registerDiscovery(dispatch: Dispatch) {
   }
 
   function handleServices() {
-    store.set('services', filterServicesToPersist(client.services))
+    if (!disableCache) {
+      store.set('services', filterServicesToPersist(client.services))
+    }
     dispatch({
       type: 'discovery:UPDATE_LIST',
       payload: { robots: client.services },

app/src/components/NetworkSettingsCard/index.js

@@ -4,13 +4,15 @@ import * as React from 'react'
 import { Card } from '@opentrons/components'
 import { AddManualIp } from './AddManualIp'
 import { ClearDiscoveryCache } from './ClearDiscoveryCache'
+import { CachingToggle } from './toggleDiscoveryCaching'
 
 // TODO(mc, 2020-04-27): i18n
 const NETWORK_SETTINGS = 'Network Settings'
 
 export const NetworkSettingsCard = () => (
   <Card title={NETWORK_SETTINGS}>
     <AddManualIp />
+    <CachingToggle />
     <ClearDiscoveryCache />
   </Card>
 )

app/src/components/NetworkSettingsCard/toggleDiscoveryCaching.js

@@ -0,0 +1,48 @@
+// @flow
+import * as React from 'react'
+import { connect } from 'react-redux'
+import { LabeledToggle } from '@opentrons/components'
+import type { State, Dispatch } from '../../types'
+import { getConfig, toggleDiscoveryCache } from '../../config'
+
+type OP = {||}
+
+type SP = {| cacheDisabled: boolean |}
+
+type DP = {| toggleCacheDisable: () => mixed |}
+
+type Props = {| ...SP, ...DP |}
+
+export const CachingToggle = connect<Props, OP, _, _, _, _>(
+  mapStateToProps,
+  mapDispatchToProps
+)(CachingToggleComponent)
+
+function CachingToggleComponent(props: Props) {
+  return (
+    <LabeledToggle
+      label="Disable robot caching"
+      toggledOn={props.cacheDisabled}
+      onClick={props.toggleCacheDisable}
+    >
+      <p>
+        Disable caching of discovered robots. The app will not remember
+        previously discovered robots.
+      </p>
+    </LabeledToggle>
+  )
+}
+
+function mapStateToProps(state: State): SP {
+  const config = getConfig(state)
+
+  return {
+    cacheDisabled: config.discovery.disableCache,
+  }
+}
+
+function mapDispatchToProps(dispatch: Dispatch): DP {
+  return {
+    toggleCacheDisable: () => dispatch(toggleDiscoveryCache()),
+  }
+}

app/src/config/actions.js

@@ -41,6 +41,12 @@ export function toggleDevInternalFlag(flag: DevInternalFlag): ThunkAction {
   }
 }
 
+export function toggleDiscoveryCache(): ThunkAction {
+  return (dispatch, getState) => {
+    const cacheDisabled = getConfig(getState()).discovery.disableCache
+    return dispatch(updateConfig('discovery.disableCache', !cacheDisabled))
+  }
+}
 // TODO(mc, 2020-02-05): move to `discovery` module
 export function addManualIp(ip: string): ThunkAction {
   return (dispatch, getState) => {