Add storage subscription API endpoints (#126)

* Add storage subscriptions

* StorageResult formatting

* Decoding WIP

* Storage subsciptions in place

* Allow null decodes, ref https://github.com/polkadot-js/apps/issues/215

* e2e tests for subscribeStorage

* Cache subscription results, return with changeset

packages/api-provider/src/mock/mocks.ts

@@ -84,6 +84,6 @@ export default function mocks ({ emitter, storage, subscriptions }: MockState):
 
     setStorageBn(storage, stateTimestamp.current, Math.floor(Date.now() / 1000));
 
-    updateSubs(subscriptions, 'subscribe_newHead', headerEncode(newHead));
+    updateSubs(subscriptions, 'chain_subscribeNewHead', headerEncode(newHead));
   }, 5000);
 }

packages/api-provider/src/mock/state.spec.js

@@ -24,7 +24,7 @@ describe('state', () => {
     expect(
       state.subscriptions
     ).toMatchObject({
-      'subscribe_newHead': {
+      'chain_subscribeNewHead': {
         callbacks: {},
         lastValue: null
       }

packages/api-provider/src/mock/state.ts

@@ -18,8 +18,8 @@ const SUBSCRIPTIONS: string[] = Array.prototype.concat.apply(
       .filter((method) =>
         method.isSubscription
       )
-      .map(({ name }) =>
-        `subscribe_${name}`
+      .map(({ name, section }) =>
+        `${section}_${name}`
       )
   )
 );

packages/api-provider/src/mock/subscribe.spec.js

@@ -19,7 +19,7 @@ describe('subscribe', () => {
   });
 
   it('returns a subscription id', () => {
-    return subscribe(state, 'subscribe_newHead', [() => void 0]).then((id) => {
+    return subscribe(state, 'chain_subscribeNewHead', [() => void 0]).then((id) => {
       expect(id).toEqual(state.subscriptionId);
     });
   });
@@ -27,16 +27,16 @@ describe('subscribe', () => {
   it('stores the mapping values', () => {
     const cb = () => void 0;
 
-    return subscribe(state, 'subscribe_newHead', [cb]).then((id) => {
-      expect(state.subscriptionMap[id]).toEqual('subscribe_newHead');
-      expect(state.subscriptions['subscribe_newHead'].callbacks[id]).toEqual(cb);
+    return subscribe(state, 'chain_subscribeNewHead', [cb]).then((id) => {
+      expect(state.subscriptionMap[id]).toEqual('chain_subscribeNewHead');
+      expect(state.subscriptions['chain_subscribeNewHead'].callbacks[id]).toEqual(cb);
     });
   });
 
   it('calls back with the last known value', (done) => {
-    state.subscriptions['subscribe_newHead'].lastValue = 'testValue';
+    state.subscriptions['chain_subscribeNewHead'].lastValue = 'testValue';
 
-    subscribe(state, 'subscribe_newHead', [(_, value) => {
+    subscribe(state, 'chain_subscribeNewHead', [(_, value) => {
       expect(value).toEqual('testValue');
       done();
     }]);

packages/api-provider/src/mock/unsubscribe.spec.js

@@ -13,23 +13,23 @@ describe('unsubscribe', () => {
   beforeEach(() => {
     state = createState();
 
-    return subscribe(state, 'subscribe_newHead', [() => void 0]).then((_id) => {
+    return subscribe(state, 'chain_subscribeNewHead', [() => void 0]).then((_id) => {
       id = _id;
     });
   });
 
   it('fails on unknown ids', () => {
-    return unsubscribe(state, 'subscribe_newHead', 5).catch((error) => {
+    return unsubscribe(state, 'chain_subscribeNewHead', 5).catch((error) => {
       expect(error.message).toMatch(/Unable to find/);
     });
   });
 
   it('unsubscribes successfully', () => {
-    return unsubscribe(state, 'subscribe_newHead', id);
+    return unsubscribe(state, 'chain_subscribeNewHead', id);
   });
 
   it('fails on double unsubscribe', () => {
-    return unsubscribe(state, 'subscribe_newHead', id)
+    return unsubscribe(state, 'chain_subscribeNewHead', id)
       .then(() => unsubscribe(state, id))
       .catch((error) => {
         expect(error.message).toMatch(/Unable to find/);
@@ -37,9 +37,9 @@ describe('unsubscribe', () => {
   });
 
   it('clears the subscriptions', () => {
-    return unsubscribe(state, 'subscribe_newHead', id).then(() => {
+    return unsubscribe(state, 'chain_subscribeNewHead', id).then(() => {
       expect(state.subscriptionMap[id]).not.toBeDefined();
-      expect(state.subscriptions['subscribe_newHead'].callbacks[id]).not.toBeDefined();
+      expect(state.subscriptions['chain_subscribeNewHead'].callbacks[id]).not.toBeDefined();
     });
   });
 });

packages/api-provider/test/e2e.test.js

@@ -0,0 +1,59 @@
+// Copyright 2017-2018 @polkadot/api-provider authors & contributors
+// This software may be modified and distributed under the terms
+// of the ISC license. See the LICENSE file for details.
+
+import storage from '@polkadot/storage';
+
+import createApi from '../../api/src';
+import Ws from '../src/ws';
+
+describe.skip('e2e', () => {
+  let api;
+
+  beforeEach(() => {
+    jest.setTimeout(30000);
+    api = createApi(new Ws('ws://127.0.0.1:9944'));
+  });
+
+  it('subscribes to chain_subscribeNewHead', (done) => {
+    let count = 0;
+
+    // tslint:disable-next-line
+    api.chain
+      .subscribeNewHead((error, data) => {
+        if (error) {
+          return done(error);
+        }
+
+        expect(data).toBeDefined();
+
+        if (++count === 3) {
+          done();
+        }
+      })
+      .then((subscriptionId) => {
+        console.log('newHead: subscriptionId =', subscriptionId);
+      });
+  });
+
+  it('subscribes to storage', (done) => {
+    api.state
+      .subscribeStorage([
+        [storage.staking.public.freeBalanceOf, '5Ejbye9R8ygByQPrDSasaUid1munedPZUmg4f118HGmtodGp'],
+        [storage.staking.public.freeBalanceOf, '5DTestUPts3kjeXSTMyerHihn1uwMfLj8vU8sqF7qYrFacT7']
+      ], (error, data) => {
+        if (error) {
+          return done(error);
+        }
+
+        expect(data).toHaveLength(2);
+        expect(data[0].toNumber()).toEqual(0);
+        expect(data[1].toNumber()).not.toEqual(0);
+
+        done();
+      })
+      .then((subscriptionId) => {
+        console.log('newHead: subscriptionId =', subscriptionId);
+      });
+  });
+});

packages/api-provider/test/e2e.test.ts

@@ -1,36 +0,0 @@
-// Copyright 2017-2018 @polkadot/api-provider authors & contributors
-// This software may be modified and distributed under the terms
-// of the ISC license. See the LICENSE file for details.
-
-import { ApiInterface } from '../../api/src/types';
-
-import createApi from '../../api/src';
-import Ws from '../src/ws';
-
-describe.skip('e2e', () => {
-  let api: ApiInterface;
-
-  beforeEach(() => {
-    jest.setTimeout(30000);
-    api = createApi(new Ws('ws://127.0.0.1:9944'));
-  });
-
-  it('subscribes to client_newHead', (done) => {
-    let count = 0;
-
-    // tslint:disable-next-line
-    api.chain
-      .newHead((error: Error | null, data: any) => {
-        console.log('newHead: result =', [error, data]);
-
-        expect(data).toBeDefined();
-
-        if (++count === 3) {
-          done();
-        }
-      })
-      .then((subscriptionId) => {
-        console.log('newHead: subscriptionId =', subscriptionId);
-      });
-  });
-});