Delete unused subscriptions after deleting columns

packages/shared/src/redux/actions/subscriptions.ts

@@ -1,10 +1,5 @@
-import { ColumnSubscription, Omit } from '../../types'
 import { createActionCreatorCreator } from '../../utils/helpers/redux'
 
-export const addColumnSubscription = createActionCreatorCreator(
-  'ADD_COLUMN_SUBSCRIPTION',
-)<Omit<ColumnSubscription, 'id' | 'createdAt' | 'updatedAt'>>()
-
 export const deleteColumnSubscription = createActionCreatorCreator(
   'DELETE_COLUMN_SUBSCRIPTION',
 )<string>()

packages/shared/src/redux/reducers/columns.ts

@@ -49,6 +49,19 @@ export const columnsReducer: Reducer<State> = (
         if (draft.byId) delete draft.byId[action.payload]
       })
 
+    case 'DELETE_COLUMN_SUBSCRIPTION':
+      return immer(state, draft => {
+        if (!(draft.allIds && draft.byId)) return
+
+        draft.allIds.forEach(columnId => {
+          if (!draft.byId![columnId].subscriptionIds) return
+
+          draft.byId![columnId].subscriptionIds = draft.byId![
+            columnId
+          ].subscriptionIds.filter(id => id !== action.payload)
+        })
+      })
+
     case 'MOVE_COLUMN':
       return immer(state, draft => {
         if (!draft.allIds) return

packages/shared/src/redux/reducers/subscriptions.ts

@@ -38,6 +38,14 @@ export const subscriptionsReducer: Reducer<State> = (
         )
       })
 
+    case 'DELETE_COLUMN_SUBSCRIPTION':
+      return immer(state, draft => {
+        if (draft.allIds)
+          draft.allIds = draft.allIds.filter(id => id !== action.payload)
+
+        if (draft.byId) delete draft.byId[action.payload]
+      })
+
     case 'REPLACE_COLUMNS':
       return immer(state, draft => {
         draft.allIds = []

packages/shared/src/redux/sagas/index.ts

@@ -3,11 +3,13 @@ import { all, fork } from 'redux-saga/effects'
 import { authSagas } from './auth'
 import { columnsSagas } from './columns'
 import { configSagas } from './config'
+import { subscriptionsSagas } from './subscriptions'
 
 export function* rootSaga() {
   yield all([
     yield fork(authSagas),
     yield fork(columnsSagas),
     yield fork(configSagas),
+    yield fork(subscriptionsSagas),
   ])
 }

packages/shared/src/redux/sagas/subscriptions.ts

@@ -0,0 +1,43 @@
+import _ from 'lodash'
+import { all, put, select, takeLatest } from 'redux-saga/effects'
+
+import { Column } from '../../types'
+import * as actions from '../actions'
+import * as selectors from '../selectors'
+
+function* cleanupSubscriptions() {
+  const allSubscriptionIds: string[] = yield select(
+    selectors.subscriptionIdsSelector,
+  )
+  if (!(allSubscriptionIds && allSubscriptionIds.length)) return
+
+  const columns: Column[] | null = yield select(selectors.columnsArrSelector)
+  if (!(columns && columns.length)) return
+
+  const usedSubscriptionIds = _.uniq(
+    columns
+      .reduce(
+        (result, column) => result.concat(column.subscriptionIds),
+        [] as string[],
+      )
+      .filter(Boolean),
+  )
+
+  const unusedSubscriptionIds = _.difference(
+    allSubscriptionIds,
+    usedSubscriptionIds,
+  )
+
+  yield all(
+    unusedSubscriptionIds.map(subscriptionId =>
+      put(actions.deleteColumnSubscription(subscriptionId)),
+    ),
+  )
+}
+
+export function* subscriptionsSagas() {
+  yield all([
+    yield takeLatest('DELETE_COLUMN', cleanupSubscriptions),
+    yield takeLatest('REPLACE_COLUMNS', cleanupSubscriptions),
+  ])
+}

packages/shared/src/redux/selectors/columns.ts

@@ -1,4 +1,5 @@
 import { createSelector } from 'reselect'
+
 import { RootState } from '../../types'
 import { createSubscriptionSelector } from './subscriptions'
 

packages/shared/src/redux/selectors/subscriptions.ts

@@ -1,8 +1,11 @@
 import { createSelector } from 'reselect'
+
 import { RootState } from '../../types'
 
 const s = (state: RootState) => state.subscriptions || {}
 
+export const subscriptionIdsSelector = (state: RootState) => s(state).allIds
+
 export const createSubscriptionSelector = () =>
   createSelector(
     (state: RootState) => s(state).byId,