Provider emits connected/disconnected (#76)

* Add provider.on stub (mock/http)

* Emit connected/disconnected from ws

* Update dependencies

* Expose .on on api

packages/api-provider/src/http/index.js

@@ -3,10 +3,11 @@
 // of the ISC license. See the LICENSE file for details.
 // @flow
 
-import type { ProviderInterface, ProviderInterface$Callback } from '../types';
+import type { ProviderInterface, ProviderInterface$Callback, ProviderInterface$Emitted, ProviderInterface$EmitCb } from '../types';
 
 require('./polyfill');
 
+const on = require('./on');
 const send = require('./send');
 const subscribe = require('./subscribe');
 const state = require('./state');
@@ -18,6 +19,8 @@ module.exports = function httpProvider (endpoint: string): ProviderInterface {
   return {
     isConnected: (): boolean =>
       true,
+    on: (type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void =>
+      on(self, type, sub),
     send: (method: string, params: Array<mixed>): Promise<mixed> =>
       send(self, method, params),
     subscribe: (method: string, params: Array<mixed>, cb: ProviderInterface$Callback): Promise<number> =>

packages/api-provider/src/http/on.js

@@ -0,0 +1,11 @@
+// Copyright 2017-2018 Jaco Greeff
+// This software may be modified and distributed under the terms
+// of the ISC license. See the LICENSE file for details.
+// @flow
+
+import type { ProviderInterface$Emitted, ProviderInterface$EmitCb } from '../types';
+import type { HttpState } from './types';
+
+module.exports = function on (self: HttpState, type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void {
+  self.l.error(`Provider does not have 'on' emitters for type '${type}'`);
+};

packages/api-provider/src/mock/index.js

@@ -3,9 +3,10 @@
 // of the ISC license. See the LICENSE file for details.
 // @flow
 
-import type { ProviderInterface } from '../types';
+import type { ProviderInterface, ProviderInterface$Emitted, ProviderInterface$EmitCb } from '../types';
 
 const mocks = require('./mocks');
+const on = require('./on');
 const send = require('./send');
 const state = require('./state');
 const subscribe = require('./subscribe');
@@ -19,6 +20,8 @@ module.exports = function mockProvider (): ProviderInterface {
   return {
     isConnected: (): boolean =>
       true,
+    on: (type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void =>
+      on(self, type, sub),
     send: (method: string, params: Array<mixed>): Promise<mixed> =>
       send(self, method, params),
     subscribe: (method: string, ...params: Array<mixed>): Promise<number> =>

packages/api-provider/src/mock/on.js

@@ -0,0 +1,11 @@
+// Copyright 2017-2018 Jaco Greeff
+// This software may be modified and distributed under the terms
+// of the ISC license. See the LICENSE file for details.
+// @flow
+
+import type { ProviderInterface$Emitted, ProviderInterface$EmitCb } from '../types';
+import type { MockState } from './types';
+
+module.exports = function on (self: MockState, type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void {
+  self.l.error(`Provider does not have 'on' emitters for type '${type}'`);
+};

packages/api-provider/src/types.js

@@ -38,8 +38,14 @@ export type JsonRpcResponse = JsonRpcObject & JsonRpcResponseBase;
 
 export type ProviderInterface$Callback = (error: ?Error, result: mixed) => void;
 
+export type ProviderInterface$Emitted = 'connected' | 'disconnected';
+
+// flowlint-next-line unclear-type:off
+export type ProviderInterface$EmitCb = (value?: any) => any;
+
 export type ProviderInterface = {
   isConnected (): boolean,
+  on (type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void,
   send (method: string, params: Array<mixed>): Promise<mixed>,
   subscribe (method: string, params: Array<mixed>, cb: ProviderInterface$Callback): Promise<number>,
   unsubscribe (method: string, id: number): Promise<boolean>

packages/api-provider/src/ws/index.js

@@ -3,11 +3,12 @@
 // of the ISC license. See the LICENSE file for details.
 // @flow
 
-import type { ProviderInterface, ProviderInterface$Callback } from '../types';
+import type { ProviderInterface, ProviderInterface$Callback, ProviderInterface$Emitted, ProviderInterface$EmitCb } from '../types';
 
 require('./polyfill');
 
 const connect = require('./connect');
+const on = require('./on');
 const send = require('./send');
 const state = require('./state');
 const subscribe = require('./subscribe');
@@ -25,6 +26,8 @@ module.exports = function wsProvider (endpoint: string, autoConnect: boolean = t
       connect(self),
     isConnected: (): boolean =>
       self.isConnected,
+    on: (type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void =>
+      on(self, type, sub),
     send: (method: string, params: Array<mixed>): Promise<mixed> =>
       send(self, method, params),
     subscribe: (method: string, params: Array<mixed>, cb: ProviderInterface$Callback): Promise<number> =>

packages/api-provider/src/ws/on.js

@@ -0,0 +1,11 @@
+// Copyright 2017-2018 Jaco Greeff
+// This software may be modified and distributed under the terms
+// of the ISC license. See the LICENSE file for details.
+// @flow
+
+import type { ProviderInterface$Emitted, ProviderInterface$EmitCb } from '../types';
+import type { WsState } from './types';
+
+module.exports = function on (self: WsState, type: ProviderInterface$Emitted, sub: ProviderInterface$EmitCb): void {
+  self.emitter.on(type, sub);
+};

packages/api-provider/src/ws/onClose.js

@@ -10,6 +10,7 @@ module.exports = function onClose (self: WsState): () => void {
     self.l.debug(() => ['disconnected from', self.endpoint]);
 
     self.isConnected = false;
+    self.emitter.emit('disconnected');
 
     if (self.autoConnect) {
       setTimeout(() => {

packages/api-provider/src/ws/onOpen.js

@@ -10,6 +10,7 @@ module.exports = function onOpen (self: WsState): () => boolean {
     self.l.debug(() => ['connected to', self.endpoint]);
 
     self.isConnected = true;
+    self.emitter.emit('connected');
 
     Object.keys(self.queued).forEach((id) => {
       try {

packages/api-provider/src/ws/state.js

@@ -5,6 +5,7 @@
 
 import type { WsState } from './types';
 
+const EventEmitter = require('eventemitter3');
 const assert = require('@polkadot/util/assert');
 const l = require('@polkadot/util/logger')('api-ws');
 
@@ -16,6 +17,7 @@ module.exports = function state (endpoint: string, autoConnect: boolean): $Shape
   return {
     autoConnect,
     coder: coder(),
+    emitter: new EventEmitter(),
     endpoint,
     handlers: {},
     isConnected: false,

packages/api-provider/src/ws/types.js

@@ -3,6 +3,7 @@
 // of the ISC license. See the LICENSE file for details.
 // @flow
 
+import type EventEmitter from 'eventemitter3';
 import type { Logger } from '@polkadot/util/types';
 import type { RpcCoder } from '../coder/json/types';
 import type { ProviderInterface$Callback } from '../types';
@@ -20,6 +21,7 @@ export type WsState = {
   autoConnect: boolean,
   coder: RpcCoder,
   endpoint: string,
+  emitter: EventEmitter,
   handlers: { [number]: WsState$Awaiting },
   isConnected: boolean,
   l: Logger,