feat(cordis): support custom inject checker, check entry injections

Author: shigma

packages/core/src/context.ts

@@ -55,7 +55,6 @@ export class Context {
   static readonly static: unique symbol = symbols.static as any
   static readonly filter: unique symbol = symbols.filter as any
   static readonly expose: unique symbol = symbols.expose as any
-  static readonly inject: unique symbol = symbols.inject as any
   static readonly isolate: unique symbol = symbols.isolate as any
   static readonly internal: unique symbol = symbols.internal as any
   static readonly intercept: unique symbol = symbols.intercept as any
@@ -104,14 +103,8 @@ export class Context {
         if (name[0] === '$' || name[0] === '_') return
         // Case 4: access directly from root
         if (!ctx.runtime.plugin) return
-        // Case 5: inject in ancestor contexts
-        let parent = ctx
-        while (parent.runtime.plugin) {
-          for (const key of parent.runtime.inject) {
-            if (name === Context.resolveInject(parent, key)[0]) return
-          }
-          parent = parent.scope.parent
-        }
+        // Case 5: custom inject checks
+        if (ctx.bail('internal/inject', name)) return
         ctx.emit('internal/warning', new Error(`property ${name} is not registered, declare it as \`inject\` to suppress this warning`))
       }
 
@@ -164,7 +157,6 @@ export class Context {
   constructor(config?: any) {
     const self: Context = new Proxy(this, Context.handler)
     config = resolveConfig(this.constructor, config)
-    self[symbols.inject] = {}
     self[symbols.isolate] = Object.create(null)
     self[symbols.intercept] = Object.create(null)
     self.root = self

packages/core/src/events.ts

@@ -95,6 +95,17 @@ export class Lifecycle {
         }
       }
     }, { global: true }), Context.static, root.scope)
+
+    // inject in ancestor contexts
+    defineProperty(this.on('internal/inject', function (name) {
+      let parent = this
+      while (parent.runtime.plugin) {
+        for (const key of parent.runtime.inject) {
+          if (name === Context.resolveInject(parent, key)[0]) return true
+        }
+        parent = parent.scope.parent
+      }
+    }, { global: true }), Context.static, root.scope)
   }
 
   async flush() {
@@ -224,6 +235,7 @@ export interface Events<in C extends Context = Context> {
   'internal/service'(this: C, name: string, value: any): void
   'internal/before-update'(fork: ForkScope<C>, config: any): void
   'internal/update'(fork: ForkScope<C>, oldConfig: any): void
+  'internal/inject'(this: C, name: string): boolean | undefined
   'internal/listener'(this: C, name: string, listener: any, prepend: boolean): void
   'internal/event'(type: 'emit' | 'parallel' | 'serial' | 'bail', name: string, args: any[], thisArg: any): void
 }

packages/core/src/scope.ts

@@ -77,7 +77,6 @@ export abstract class EffectScope<C extends Context = Context> {
   constructor(public parent: C, public config: C['config']) {
     this.uid = parent.registry ? parent.registry.counter : 0
     this.ctx = this.context = parent.extend({ scope: this })
-    this.ctx[Context.inject] = {}
     this.proxy = new Proxy({}, {
       get: (target, key) => Reflect.get(this.config, key),
     })
@@ -360,7 +359,6 @@ export class MainScope<C extends Context = Context> extends EffectScope<C> {
     if (name && name !== 'apply') this.name = name
     this.schema = this.plugin['Config'] || this.plugin['schema']
     this.setInject(this.plugin['using'] || this.plugin['inject'])
-    this.setInject(this.parent[Context.inject])
     this.isReusable = this.plugin['reusable']
     this.isReactive = this.plugin['reactive']
     this.context.emit('internal/runtime', this)

packages/core/src/utils.ts

@@ -8,7 +8,6 @@ export const symbols = {
   static: Symbol.for('cordis.static') as typeof Context.static,
   filter: Symbol.for('cordis.filter') as typeof Context.filter,
   expose: Symbol.for('cordis.expose') as typeof Context.expose,
-  inject: Symbol.for('cordis.inject') as typeof Context.inject,
   isolate: Symbol.for('cordis.isolate') as typeof Context.isolate,
   internal: Symbol.for('cordis.internal') as typeof Context.internal,
   intercept: Symbol.for('cordis.intercept') as typeof Context.intercept,

packages/loader/src/entry.ts

@@ -61,8 +61,6 @@ export class Entry {
   }
 
   patch(ctx: Context, ref: Context = ctx) {
-    ctx[Context.inject] = this.options.inject
-
     // part 1: prepare isolate map
     const newMap: Dict<symbol> = Object.create(Object.getPrototypeOf(ref[Context.isolate]))
     for (const [key, label] of Object.entries(this.options.isolate ?? {})) {
@@ -144,11 +142,51 @@ export class Entry {
     })
   }
 
+  get requiredInjects() {
+    return Array.isArray(this.options.inject)
+      ? this.options.inject
+      : this.options.inject?.required ?? []
+  }
+
+  get optionalInjects() {
+    return Array.isArray(this.options.inject)
+      ? this.options.inject
+      : [
+        ...this.options.inject?.required ?? [],
+        ...this.options.inject?.optional ?? [],
+      ]
+  }
+
+  _check() {
+    if (!this.loader.isTruthyLike(this.options.when)) return false
+    if (this.options.disabled) return false
+    for (const name of this.requiredInjects) {
+      let key = this.parent.ctx[Context.isolate][name]
+      const label = this.options.isolate?.[name]
+      if (label) {
+        const realm = this.resolveRealm(label)
+        key = (this.loader.realms[realm] ?? Object.create(null))[name] ?? Symbol(`${name}${realm}`)
+      }
+      if (!key || isNullable(this.parent.ctx[key])) return false
+    }
+    return true
+  }
+
+  async checkService(name: string) {
+    if (!this.requiredInjects.includes(name)) return
+    const ready = this._check()
+    if (ready && !this.fork) {
+      await this.start()
+    } else if (!ready && this.fork) {
+      await this.stop()
+    }
+  }
+
   async update(options: Entry.Options) {
     const legacy = this.options
     this.options = sortKeys(options)
-    if (!this.loader.isTruthyLike(options.when) || options.disabled) {
-      this.stop()
+    if (!this._check()) {
+      await this.stop()
     } else if (this.fork) {
       this.suspend = true
       for (const [key, label] of Object.entries(legacy.isolate ?? {})) {
@@ -158,21 +196,25 @@ export class Entry {
       }
       this.patch(this.fork.parent)
     } else {
-      const ctx = this.createContext()
-      const exports = await this.loader.import(this.options.name).catch((error: any) => {
-        ctx.emit('internal/error', new Error(`Cannot find package "${this.options.name}"`))
-        ctx.emit('internal/error', error)
-      })
-      if (!exports) return
-      const plugin = this.loader.unwrapExports(exports)
-      this.patch(ctx)
-      ctx[Entry.key] = this
-      this.fork = ctx.plugin(plugin, this.options.config)
-      ctx.emit('loader/entry', 'apply', this)
+      await this.start()
     }
   }
 
-  stop() {
+  async start() {
+    const ctx = this.createContext()
+    const exports = await this.loader.import(this.options.name, this.parent.url).catch((error: any) => {
+      ctx.emit('internal/error', new Error(`Cannot find package "${this.options.name}"`))
+      ctx.emit('internal/error', error)
+    })
+    if (!exports) return
+    const plugin = this.loader.unwrapExports(exports)
+    this.patch(ctx)
+    ctx[Entry.key] = this
+    this.fork = ctx.plugin(plugin, this.options.config)
+    ctx.emit('loader/entry', 'apply', this)
+  }
+
+  async stop() {
     this.fork?.dispose()
     this.fork = undefined
 

packages/loader/src/shared.ts

@@ -64,6 +64,8 @@ export abstract class Loader extends BaseLoader {
 
   constructor(public ctx: Context, public config: Loader.Config) {
     super(ctx)
+
+    const self = this
     this.ctx.set('loader', this)
     this.realms['#'] = ctx.root[Context.isolate]
 
@@ -98,6 +100,31 @@ export abstract class Loader extends BaseLoader {
       fork.entry.stop()
       fork.entry.parent.write()
     })
+
+    this.ctx.on('internal/before-service', function (name) {
+      for (const entry of Object.values(self.entries)) {
+        entry.checkService(name)
+      }
+    }, { global: true })
+
+    this.ctx.on('internal/service', function (name) {
+      for (const entry of Object.values(self.entries)) {
+        entry.checkService(name)
+      }
+    }, { global: true })
+
+    const checkInject = (scope: EffectScope, name: string) => {
+      if (!scope.runtime.plugin) return false
+      if (scope.runtime === scope) {
+        return scope.runtime.children.every(fork => checkInject(fork, name))
+      }
+      if (scope.entry?.optionalInjects.includes(name)) return true
+      return checkInject(scope.parent.scope, name)
+    }
+
+    this.ctx.on('internal/inject', function (this, name) {
+      return checkInject(this.scope, name)
+    })
   }
 
   async start() {
@@ -188,11 +215,11 @@ export abstract class Loader extends BaseLoader {
 
   _locate(scope: EffectScope): Entry[] {
     // root scope
-    if (scope === scope.parent.scope) return []
+    if (!scope.runtime.plugin) return []
 
     // runtime scope
     if (scope.runtime === scope) {
-      return ([] as Entry[]).concat(...scope.runtime.children.map(child => this._locate(child)))
+      return scope.runtime.children.flatMap(child => this._locate(child))
     }
 
     if (scope.entry) return [scope.entry]