feat(context): consolidate uuid generation and testing

packages/context/src/__tests__/unit/binding-key.unit.ts

@@ -5,6 +5,7 @@
 
 import {expect} from '@loopback/testlab';
 import {BindingKey} from '../..';
+import {UUID_PATTERN} from '../../value-promise';
 
 describe('BindingKey', () => {
   describe('create', () => {
@@ -62,17 +63,15 @@ describe('BindingKey', () => {
   describe('generate', () => {
     it('generates binding key without namespace', () => {
       const key1 = BindingKey.generate().key;
-      expect(key1).to.match(
-        /^[0-9A-F]{8}-[0-9A-F]{4}-[4][0-9A-F]{3}-[89AB][0-9A-F]{3}-[0-9A-F]{12}$/i,
-      );
+      expect(key1).to.match(UUID_PATTERN);
       const key2 = BindingKey.generate().key;
       expect(key1).to.not.eql(key2);
     });
 
     it('generates binding key with namespace', () => {
       const key1 = BindingKey.generate('services').key;
       expect(key1).to.match(
-        /^services\.[0-9A-F]{8}-[0-9A-F]{4}-[4][0-9A-F]{3}-[89AB][0-9A-F]{3}-[0-9A-F]{12}$/i,
+        new RegExp(`^services\\.${UUID_PATTERN.source}$`, 'i'),
       );
       const key2 = BindingKey.generate('services').key;
       expect(key1).to.not.eql(key2);

packages/context/src/__tests__/unit/context.unit.ts

@@ -17,6 +17,7 @@ import {
   isPromiseLike,
   Provider,
 } from '../..';
+import {UUID_PATTERN} from '../../value-promise';
 
 /**
  * Create a subclass of context so that we can access parents and registry
@@ -45,15 +46,13 @@ class TestContext extends Context {
 describe('Context constructor', () => {
   it('generates uuid name if not provided', () => {
     const ctx = new Context();
-    expect(ctx.name).to.match(
-      /^[0-9A-F]{8}-[0-9A-F]{4}-[4][0-9A-F]{3}-[89AB][0-9A-F]{3}-[0-9A-F]{12}$/i,
-    );
+    expect(ctx.name).to.match(UUID_PATTERN);
   });
 
   it('adds subclass name as the prefix', () => {
     const ctx = new TestContext();
     expect(ctx.name).to.match(
-      /^TestContext-[0-9A-F]{8}-[0-9A-F]{4}-[4][0-9A-F]{3}-[89AB][0-9A-F]{3}-[0-9A-F]{12}$/i,
+      new RegExp(`^TestContext-${UUID_PATTERN.source}$`, 'i'),
     );
   });
 

packages/context/src/__tests__/unit/interceptor.unit.ts

@@ -20,6 +20,7 @@ import {
   Provider,
 } from '../..';
 import {registerInterceptor} from '../../interceptor';
+import {UUID_PATTERN} from '../../value-promise';
 
 describe('mergeInterceptors', () => {
   it('removes duplicate entries from the spec', () => {
@@ -259,6 +260,18 @@ describe('globalInterceptors', () => {
     expect(keys).to.eql(['globalInterceptors.logInterceptor']);
   });
 
+  it('infers binding key from the interceptor function', () => {
+    const binding = registerInterceptor(ctx, logInterceptor);
+    expect(binding.key).to.eql('interceptors.logInterceptor');
+  });
+
+  it('generates binding key for the interceptor function', () => {
+    const binding = registerInterceptor(ctx, () => {});
+    expect(binding.key).to.match(
+      new RegExp(`interceptors.${UUID_PATTERN.source}`, 'i'),
+    );
+  });
+
   class MyController {
     greet(name: string) {
       return `Hello, ${name}`;

packages/context/src/binding-key.ts

@@ -3,7 +3,8 @@
 // This file is licensed under the MIT License.
 // License text available at https://opensource.org/licenses/MIT
 
-import {v4} from 'uuid';
+import {uuid} from './value-promise';
+
 export type BindingAddress<T = unknown> = string | BindingKey<T>;
 
 export class BindingKey<ValueType> {
@@ -127,7 +128,7 @@ export class BindingKey<ValueType> {
    */
   static generate<T>(namespace = ''): BindingKey<T> {
     const prefix = namespace ? `${namespace}.` : '';
-    const uuid = v4();
-    return BindingKey.create(`${prefix}${uuid}`);
+    const name = uuid();
+    return BindingKey.create(`${prefix}${name}`);
   }
 }

packages/context/src/context.ts

@@ -5,7 +5,6 @@
 
 import debugFactory, {Debugger} from 'debug';
 import {EventEmitter} from 'events';
-import {v4 as uuidv4} from 'uuid';
 import {Binding, BindingInspectOptions, BindingTag} from './binding';
 import {
   ConfigurationResolver,
@@ -37,6 +36,7 @@ import {
   Constructor,
   getDeepProperty,
   isPromiseLike,
+  uuid,
   ValueOrPromise,
 } from './value-promise';
 
@@ -151,7 +151,7 @@ export class Context extends EventEmitter {
   }
 
   private generateName() {
-    const id = uuidv4();
+    const id = uuid();
     if (this.constructor === Context) return id;
     return `${this.constructor.name}-${id}`;
   }

packages/context/src/value-promise.ts

@@ -8,6 +8,7 @@
  * utility methods to handle values and/or promises.
  */
 
+import {v4 as uuidv4} from 'uuid';
 /**
  * A class constructor accepting arbitrary arguments.
  */
@@ -270,3 +271,15 @@ export function transformValueOrPromise<T, V>(
     return transformer(valueOrPromise);
   }
 }
+
+/**
+ * A utility to generate uuid v4
+ */
+export function uuid() {
+  return uuidv4();
+}
+
+/**
+ * A regular expression for testing uuid v4 PATTERN
+ */
+export const UUID_PATTERN = /[0-9A-F]{8}-[0-9A-F]{4}-[4][0-9A-F]{3}-[89AB][0-9A-F]{3}-[0-9A-F]{12}/i;