Merge pull request #113 from jolocom/feat/events

Basic event system + Interaction updated/created events

jest.config.js

@@ -17,7 +17,7 @@ module.exports = {
     },
   },
   moduleFileExtensions: ['ts', 'node', 'js', 'json'],
-  testMatch: ['**/tests/*.test.ts'],
+  testMatch: ['**/tests/**/*.test.ts'],
   testPathIgnorePatterns: ['/node_modules/.*'],
   moduleNameMapper: pathsToModuleNameMapper(
     compilerOptions.paths,

package.json

@@ -55,6 +55,7 @@
     "ts-node": "^9.0.0",
     "tsconfig-paths": "^3.9.0",
     "tslib": "^1.7.1",
+    "typed-emitter": "^1.3.1",
     "typedoc": "^0.19.2",
     "typeorm": "0.2.24",
     "typescript": "^3.7.5",

src/events.ts

@@ -0,0 +1,23 @@
+import { EventEmitter } from 'events'
+import TypedEmitter from 'typed-emitter'
+
+export type Unsubscriber = () => void
+
+/**
+ * This class wraps TypedEmitter, which is a typescript overlay on
+ * the standard EventEmitter class; typings only, no code
+ */
+export class Emitter<T> extends (EventEmitter as {
+  new <T>(): Omit<TypedEmitter<T>, 'on'>
+})<T> {
+  on<E extends (string | symbol) & keyof T>(
+    event: E,
+    listener: T[E],
+  ): Unsubscriber {
+    // @ts-ignore
+    EventEmitter.prototype.on.call(this, event, listener)
+    return () => {
+      super.off(event, listener)
+    }
+  }
+}