Merge remote-tracking branch 'grafana/master' into table-reducer

* grafana/master:
  docs: renamed file and added redux framework file
  docs: moved examples to frontend.md
  docs: intial draft for frontend review doc
  Use ora#fail instead of console.log
  Remove .only function
  Add more patterns to no-only-test task

packages/grafana-ui/src/components/ThresholdsEditor/ThresholdsEditor.test.tsx

@@ -161,7 +161,7 @@ describe('change threshold value', () => {
 });
 
 describe('on blur threshold value', () => {
-  it.only('should resort rows and update indexes', () => {
+  it('should resort rows and update indexes', () => {
     const { instance } = setup();
     const thresholds = [
       { index: 0, value: -Infinity, color: '#7EB26D' },

scripts/cli/utils/useSpinner.ts

@@ -10,8 +10,7 @@ export const useSpinner = <T>(spinnerLabel: string, fn: FnToSpin<T>, killProcess
       await fn(options);
       spinner.succeed();
     } catch (e) {
-      spinner.fail();
-      console.log(e);
+      spinner.fail(e);
       if (killProcess) {
         process.exit(1);
       }

scripts/grunt/default_task.js

@@ -34,14 +34,17 @@ module.exports = function (grunt) {
   ]);
 
   grunt.registerTask('no-only-tests', function () {
-    var files = grunt.file.expand('public/**/*_specs\.ts', 'public/**/*_specs\.js');
+    var files = grunt.file.expand(
+      'public/**/*@(_specs|\.test)\.@(ts|js|tsx|jsx)',
+      'packages/grafana-ui/**/*@(_specs|\.test)\.@(ts|js|tsx|jsx)'
+    );
 
     files.forEach(function (spec) {
       var rows = grunt.file.read(spec).split('\n');
       rows.forEach(function (row) {
         if (row.indexOf('.only(') > 0) {
           grunt.log.errorlns(row);
-          grunt.fail.warn('found only statement in test: ' + spec)
+          grunt.fail.warn('found only statement in test: ' + spec);
         }
       });
     });

style_guides/frontend.md

 # Frontend Style Guide
 
-Generally we follow the Airbnb  [React Style Guide](https://github.com/airbnb/javascript/tree/master/react).
+Generally we follow the Airbnb [React Style Guide](https://github.com/airbnb/javascript/tree/master/react).
 
 ## Table of Contents
 
-  1. [Basic Rules](#basic-rules)
-  1. [File & Component Organization](#Organization)
-  1. [Naming](#naming)
-  1. [Declaration](#declaration)
-  1. [Props](#props)
-  1. [Refs](#refs)
-  1. [Methods](#methods)
-  1. [Ordering](#ordering)
+1. [Basic Rules](#basic-rules)
+1. [File & Component Organization](#Organization)
+1. [Naming](#naming)
+1. [Declaration](#declaration)
+1. [Props](#props)
+1. [Refs](#refs)
+1. [Methods](#methods)
+1. [Ordering](#ordering)
 
 ## Basic rules
 
-* Try to keep files small and focused and break large components up into sub components.
+- Try to keep files small and focused and break large components up into sub components.
 
 ## Organization
 
-* Components and types that needs to be used by external plugins needs to go into @grafana/ui
-* Components should get their own folder under features/xxx/components
-  * Sub components can live in that component folders, so small component do not need their own folder
-  * Place test next to their component file (same dir)  
-  * Component sass should live in the same folder as component code
-* State logic & domain models should live in features/xxx/state
-* Containers (pages) can live in feature root features/xxx
-  * up for debate?
+- Components and types that needs to be used by external plugins needs to go into @grafana/ui
+- Components should get their own folder under features/xxx/components
+  - Sub components can live in that component folders, so small component do not need their own folder
+  - Place test next to their component file (same dir)
+  - Component sass should live in the same folder as component code
+- State logic & domain models should live in features/xxx/state
+- Containers (pages) can live in feature root features/xxx
+  - up for debate?
 
 ## Props
 
-* Name callback props & handlers with a "on"  prefix.
+- Name callback props & handlers with a "on" prefix.
 
 ```tsx
 // good
@@ -56,5 +56,32 @@ render() {
 }
 ```
 
+- React Component definitions
 
+```jsx
+// good
+export class YourClass extends PureComponent<{},{}> { ... }
+
+// bad
+export class YourClass extends PureComponent { ... }
+```
 
+- React Component constructor
+
+```typescript
+// good
+constructor(props:Props) {...}
+
+// bad
+constructor(props) {...}
+```
+
+- React Component defaultProps
+
+```typescript
+// good
+static defaultProps: Partial<Props> = { ... }
+
+// bad
+static defaultProps = { ... }
+```

style_guides/pull-request-review-checklist.md

+# Pull Request Review Checklist
+
+## High level checks
+
+- [ ] The pull request adds value and the impact of the change is in line with [Frontend Style Guide](https://github.com/grafana/grafana/blob/master/style_guides/frontend.md).
+- [ ] The pull request works the way it says it should do.
+- [ ] The pull request does not increase the Angular code base.
+  > We are in the process of migrating to React so any increment of Angular code is generally discouraged from. (there are a few exceptions)
+- [ ] The pull request closes one issue if possible and does not fix unrelated issues within the same pull request.
+- [ ] The pull request contains necessary tests.
+
+## Low level checks
+
+- [ ] The pull request contains a title that explains the PR.
+- [ ] The pull request contains necessary link(s) to issue(s).
+- [ ] The pull request contains commits with commit messages that are small and understandable.
+- [ ] The pull request does not contain magic strings or numbers that could be replaced with an `Enum` or `const` instead.
+
+### Bug specific checks
+
+- [ ] The pull request contains only one commit if possible.
+- [ ] The pull request contains `closes: #Issue` or `fixes: #Issue` in pull request description.
+
+## Frontend specific checks
+
+- [ ] The pull request does not increase the number of `implicit any` errors.
+- [ ] The pull request does not contain uses of `any` or `{}` without comments describing why.
+- [ ] The pull request does not contain large React component that could easily be split into several smaller components.
+- [ ] The pull request does not contain back end calls directly from components, use actions and Redux instead.
+
+### Redux specific checks (skip if pull request does not contain Redux changes)
+
+- [ ] The pull request does not contain code that mutate state in reducers or thunks.
+- [ ] The pull request uses helpers `actionCreatorFactory` and `reducerFactory` instead of traditional `switch statement` reducers in Redux. ([Redux framework](https://github.com/grafana/grafana/blob/master/style_guides/redux.md))
+- [ ] The pull request uses `reducerTester` to test reducers.([Redux framework](https://github.com/grafana/grafana/blob/master/style_guides/redux.md))
+- [ ] The pull request does not contain code that access reducers state slice directly, instead the code uses state selectors to access state.

style_guides/redux.md

+# Redux framework
+
+To reduce the amount of boilerplate code used to create a strongly typed redux solution with actions, action creators, reducers and tests we've introduced a small framework around Redux.
+
+`+` Much less boilerplate code
+`-` Non Redux standard api
+
+## New core functionality
+
+### actionCreatorFactory
+
+Used to create an action creator with the following signature
+
+```typescript
+{ type: string , (payload: T): {type: string; payload: T;} }
+```
+
+where the `type` string will be ensured to be unique and `T` is the type supplied to the factory.
+
+#### Example
+
+```typescript
+export const someAction = actionCreatorFactory<string>('SOME_ACTION').create();
+
+// later when dispatched
+someAction('this rocks!');
+```
+
+```typescript
+// best practices, always use an interface as type
+interface SomeAction {
+  data: string;
+}
+export const someAction = actionCreatorFactory<SomeAction>('SOME_ACTION').create();
+
+// later when dispatched
+someAction({ data: 'best practices' });
+```
+
+```typescript
+// declaring an action creator with a type string that has already been defined will throw
+export const someAction = actionCreatorFactory<string>('SOME_ACTION').create();
+export const theAction = actionCreatorFactory<string>('SOME_ACTION').create(); // will throw
+```
+
+### noPayloadActionCreatorFactory
+
+Used when you don't need to supply a payload for your action. Will create an action creator with the following signature
+
+```typescript
+{ type: string , (): {type: string; payload: undefined;} }
+```
+
+where the `type` string will be ensured to be unique.
+
+#### Example
+
+```typescript
+export const noPayloadAction = noPayloadActionCreatorFactory('NO_PAYLOAD').create();
+
+// later when dispatched
+noPayloadAction();
+```
+
+```typescript
+// declaring an action creator with a type string that has already been defined will throw
+export const noPayloadAction = noPayloadActionCreatorFactory('NO_PAYLOAD').create();
+export const noAction = noPayloadActionCreatorFactory('NO_PAYLOAD').create(); // will throw
+```
+
+### reducerFactory
+
+Fluent API used to create a reducer. (same as implementing the standard switch statement in Redux)
+
+#### Example
+
+```typescript
+interface ExampleReducerState {
+  data: string[];
+}
+
+const intialState: ExampleReducerState = { data: [] };
+
+export const someAction = actionCreatorFactory<string>('SOME_ACTION').create();
+export const otherAction = actionCreatorFactory<string[]>('Other_ACTION').create();
+
+export const exampleReducer = reducerFactory<ExampleReducerState>(intialState)
+  // addMapper is the function that ties an action creator to a state change
+  .addMapper({
+    // action creator to filter out which mapper to use
+    filter: someAction,
+    // mapper function where the state change occurs
+    mapper: (state, action) => ({ ...state, data: state.data.concat(action.payload) }),
+  })
+  // a developer can just chain addMapper functions until reducer is done
+  .addMapper({
+    filter: otherAction,
+    mapper: (state, action) => ({ ...state, data: action.payload }),
+  })
+  .create(); // this will return the reducer
+```
+
+#### Typing limitations
+
+There is a challenge left with the mapper function that I can not solve with TypeScript. The signature of a mapper is
+
+```typescript
+<State, Payload>(state: State, action: ActionOf<Payload>) => State;
+```
+
+If you would to return an object that is not of the state type like the following mapper
+
+```typescript
+mapper: (state, action) => ({ nonExistingProperty: ''}),
+```
+
+Then you would receive the following compile error
+
+```shell
+[ts] Property 'data' is missing in type '{ nonExistingProperty: string; }' but required in type 'ExampleReducerState'. [2741]
+```
+
+But if you return an object that is spreading state and add a non existing property type like the following mapper
+
+```typescript
+mapper: (state, action) => ({ ...state, nonExistingProperty: ''}),
+```
+
+Then you would not receive any compile error.
+
+If you want to make sure that never happens you can just supply the State type to the mapper callback like the following mapper:
+
+```typescript
+mapper: (state, action): ExampleReducerState => ({ ...state, nonExistingProperty: 'kalle' }),
+```
+
+Then you would receive the following compile error
+
+```shell
+[ts]
+Type '{ nonExistingProperty: string; data: string[]; }' is not assignable to type 'ExampleReducerState'.
+  Object literal may only specify known properties, and 'nonExistingProperty' does not exist in type 'ExampleReducerState'. [2322]
+```
+
+## New test functionality
+
+### reducerTester
+
+Fluent API that simplifies the testing of reducers
+
+#### Example
+
+```typescript
+reducerTester()
+  .givenReducer(someReducer, initialState)
+  .whenActionIsDispatched(someAction('reducer tests'))
+  .thenStateShouldEqual({ ...initialState, data: 'reducer tests' });
+```