feat: scan framework dependencies as optional module (#184)

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##### Checklist
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- [x] `npm test` passes
- [x] tests and/or benchmarks are included
- [ ] documentation is changed or added
- [x] commit message follows commit guidelines

##### Affected core subsystem(s)
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##### Description of change
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- any feature?
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Author: killagu

.gitignore

@@ -40,3 +40,4 @@ plugin/tegg/test/fixtures/apps/**/*.js
 !benchmark/**/*.js
 !standalone/standalone/test/fixtures/**/node_modules
 !standalone/standalone/test/fixtures/**/node_modules/**/*.js
+!plugin/tegg/test/fixtures/**/node_modules

core/common-util/src/Graph.ts

@@ -7,6 +7,7 @@ export interface GraphNodeObj {
 export class GraphNode<T extends GraphNodeObj> {
   val: T;
   toNodeMap: Map<string, GraphNode<T>> = new Map();
+  fromNodeMap: Map<string, GraphNode<T>> = new Map();
 
   constructor(val: T) {
     this.val = val;
@@ -24,6 +25,14 @@ export class GraphNode<T extends GraphNodeObj> {
     return true;
   }
 
+  addFromVertex(node: GraphNode<T>) {
+    if (this.fromNodeMap.has(node.id)) {
+      return false;
+    }
+    this.fromNodeMap.set(node.id, node);
+    return true;
+  }
+
   [inspect]() {
     return this.toJSON();
   }
@@ -32,6 +41,7 @@ export class GraphNode<T extends GraphNodeObj> {
     return {
       val: this.val,
       toNodes: Array.from(this.toNodeMap.values()),
+      fromNodes: Array.from(this.fromNodeMap.values()),
     };
   }
 
@@ -84,6 +94,7 @@ export class Graph<T extends GraphNodeObj> {
   }
 
   addEdge(from: GraphNode<T>, to: GraphNode<T>): boolean {
+    to.addFromVertex(from);
     return from.addToVertex(to);
   }
 

core/common-util/src/ModuleConfig.ts

@@ -9,14 +9,17 @@ import extend from 'extend2';
 export interface ModuleReference {
   name: string;
   path: string;
+  optional?: boolean;
 }
 
 export interface InlineModuleReferenceConfig {
   path: string;
+  optional?: boolean;
 }
 
 export interface NpmModuleReferenceConfig {
   package: string;
+  optional?: boolean;
 }
 
 export type ModuleReferenceConfig = InlineModuleReferenceConfig | NpmModuleReferenceConfig;

core/metadata/src/model/AppGraph.ts

@@ -249,6 +249,9 @@ export class AppGraph {
       throw new Error('module has recursive deps: ' + loopPath);
     }
     this.moduleConfigList = this.graph.sort()
+      .filter(t => {
+        return t.val.moduleConfig.optional !== true || t.fromNodeMap.size > 0;
+      })
       .map(t => t.val.moduleConfig);
   }
 }

core/metadata/test/AppGraph.test.ts

@@ -0,0 +1,35 @@
+import assert from 'assert';
+import path from 'path';
+import { AppGraph, ModuleNode } from '../src/model/AppGraph';
+import { RootProto } from './fixtures/modules/app-graph-modules/root/Root';
+import { UsedProto } from './fixtures/modules/app-graph-modules/used/Used';
+import { UnusedProto } from './fixtures/modules/app-graph-modules/unused/Unused';
+
+describe('test/LoadUnit/AppGraph.test.ts', () => {
+  it('optional module dep should work', () => {
+    const graph = new AppGraph();
+    const rootModuleNode = new ModuleNode({
+      name: 'foo',
+      path: path.join(__dirname, './fixtures/modules/app-graph-modules/root'),
+    });
+    rootModuleNode.addClazz(RootProto);
+    graph.addNode(rootModuleNode);
+    const usedOptionalModuleNode = new ModuleNode({
+      name: 'usedOptionalModuleNode',
+      path: path.join(__dirname, './fixtures/modules/app-graph-modules/used'),
+      optional: true,
+    });
+    usedOptionalModuleNode.addClazz(UsedProto);
+    graph.addNode(usedOptionalModuleNode);
+    const unusedOptionalModuleNode = new ModuleNode({
+      name: 'unusedOptionalModuleNode',
+      path: path.join(__dirname, './fixtures/modules/app-graph-modules/unused'),
+      optional: true,
+    });
+    unusedOptionalModuleNode.addClazz(UnusedProto);
+    graph.addNode(unusedOptionalModuleNode);
+    graph.build();
+    graph.sort();
+    assert(graph.moduleConfigList.length === 2);
+  });
+});

core/metadata/test/fixtures/modules/app-graph-modules/root/Root.ts

@@ -0,0 +1,7 @@
+import { SingletonProto, Inject } from '@eggjs/core-decorator';
+import { UsedProto } from '../used/Used';
+
+@SingletonProto()
+export class RootProto {
+  @Inject() usedProto: UsedProto;
+}

core/metadata/test/fixtures/modules/app-graph-modules/root/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "root",
+  "eggModule": {
+    "name": "root"
+  }
+}

core/metadata/test/fixtures/modules/app-graph-modules/unused/Unused.ts

@@ -0,0 +1,5 @@
+import { SingletonProto } from '@eggjs/core-decorator';
+
+@SingletonProto()
+export class UnusedProto {
+}

core/metadata/test/fixtures/modules/app-graph-modules/unused/package.json

@@ -0,0 +1,6 @@
+{
+  "name": "unused",
+  "eggModule": {
+    "name": "unused"
+  }
+}

core/metadata/test/fixtures/modules/app-graph-modules/used/Used.ts

@@ -0,0 +1,7 @@
+import { AccessLevel, SingletonProto } from '@eggjs/core-decorator';
+
+@SingletonProto({
+  accessLevel: AccessLevel.PUBLIC,
+})
+export class UsedProto {
+}