From 05f9eb0766bec4b750592f0f0e2ef4d68fcd1939 Mon Sep 17 00:00:00 2001
From: Dominik Prokop <dominik.prokop@grafana.com>
Date: Mon, 28 Jan 2019 11:06:50 +0100
Subject: [PATCH] Update datasource before the loading has started

---
 .../app/features/explore/state/actionTypes.ts | 14 +++++++++++--
 public/app/features/explore/state/actions.ts  | 21 +++++++++++++++++--
 public/app/features/explore/state/reducers.ts |  8 +++++++
 3 files changed, 39 insertions(+), 4 deletions(-)

diff --git a/public/app/features/explore/state/actionTypes.ts b/public/app/features/explore/state/actionTypes.ts
index 4e1d658f072..0de3981b40e 100644
--- a/public/app/features/explore/state/actionTypes.ts
+++ b/public/app/features/explore/state/actionTypes.ts
@@ -1,6 +1,6 @@
 // Types
 import { Emitter } from 'app/core/core';
-import { RawTimeRange, TimeRange, DataQuery, DataSourceSelectItem  } from '@grafana/ui/src/types';
+import { RawTimeRange, TimeRange, DataQuery, DataSourceSelectItem, DataSourceApi  } from '@grafana/ui/src/types';
 import {
   ExploreId,
   ExploreItemState,
@@ -41,6 +41,7 @@ export enum ActionTypes {
   ToggleGraph = 'explore/TOGGLE_GRAPH',
   ToggleLogs = 'explore/TOGGLE_LOGS',
   ToggleTable = 'explore/TOGGLE_TABLE',
+  UpdateDatasourceInstance = 'explore/UPDATE_DATASOURCE_INSTANCE',
 }
 
 export interface AddQueryRowAction {
@@ -270,6 +271,14 @@ export interface ToggleLogsAction {
   };
 }
 
+export interface UpdateDatasourceInstanceAction {
+  type: ActionTypes.UpdateDatasourceInstance;
+  payload: {
+    exploreId: ExploreId;
+    datasourceInstance: DataSourceApi;
+  };
+}
+
 export type Action =
   | AddQueryRowAction
   | ChangeQueryAction
@@ -297,4 +306,5 @@ export type Action =
   | SplitOpenAction
   | ToggleGraphAction
   | ToggleLogsAction
-  | ToggleTableAction;
+  | ToggleTableAction
+  | UpdateDatasourceInstanceAction;
diff --git a/public/app/features/explore/state/actions.ts b/public/app/features/explore/state/actions.ts
index d4c42ffa9c7..c653f5492f8 100644
--- a/public/app/features/explore/state/actions.ts
+++ b/public/app/features/explore/state/actions.ts
@@ -21,7 +21,7 @@ import { updateLocation } from 'app/core/actions';
 
 // Types
 import { StoreState } from 'app/types';
-import { DataQuery, DataSourceSelectItem, QueryHint  } from '@grafana/ui/src/types';
+import { DataQuery, DataSourceSelectItem, QueryHint } from '@grafana/ui/src/types';
 import { getDatasourceSrv } from 'app/features/plugins/datasource_srv';
 import {
   ExploreId,
@@ -46,9 +46,9 @@ import {
   LoadDatasourceSuccessAction,
   QueryTransactionStartAction,
   ScanStopAction,
+  UpdateDatasourceInstanceAction,
 } from './actionTypes';
 
-
 type ThunkResult<R> = ThunkAction<R, StoreState, undefined, ThunkableAction>;
 
 /**
@@ -65,6 +65,7 @@ export function addQueryRow(exploreId: ExploreId, index: number): AddQueryRowAct
 export function changeDatasource(exploreId: ExploreId, datasource: string): ThunkResult<void> {
   return async dispatch => {
     const instance = await getDatasourceSrv().get(datasource);
+    dispatch(updateDatasourceInstance(exploreId, instance));
     dispatch(loadDatasource(exploreId, instance));
   };
 }
@@ -263,6 +264,22 @@ export const loadDatasourceSuccess = (
   };
 };
 
+/**
+ * Updates datasource instance before datasouce loading has started
+ */
+export function updateDatasourceInstance(
+  exploreId: ExploreId,
+  instance: DataSourceApi
+): UpdateDatasourceInstanceAction {
+  return {
+    type: ActionTypes.UpdateDatasourceInstance,
+    payload: {
+      exploreId,
+      datasourceInstance: instance,
+    },
+  };
+}
+
 /**
  * Main action to asynchronously load a datasource. Dispatches lots of smaller actions for feedback.
  */
diff --git a/public/app/features/explore/state/reducers.ts b/public/app/features/explore/state/reducers.ts
index 8885f972d06..f65f2e26ee6 100644
--- a/public/app/features/explore/state/reducers.ts
+++ b/public/app/features/explore/state/reducers.ts
@@ -176,6 +176,14 @@ export const itemReducer = (state, action: Action): ExploreItemState => {
       };
     }
 
+    case ActionTypes.UpdateDatasourceInstance: {
+      const { datasourceInstance } = action.payload;
+      return {
+        ...state,
+        datasourceInstance,
+      };
+    }
+
     case ActionTypes.LoadDatasourceFailure: {
       return { ...state, datasourceError: action.payload.error, datasourceLoading: false };
     }