ModuleGraph Class — vite Architecture

Source Code

packages/vite/src/node/server/mixedModuleGraph.ts lines 248–518

export class ModuleGraph {
  /** @internal */
  _moduleGraphs: {
    client: () => EnvironmentModuleGraph
    ssr: () => EnvironmentModuleGraph
  }

  /** @internal */
  get _client(): EnvironmentModuleGraph {
    return this._moduleGraphs.client()
  }

  /** @internal */
  get _ssr(): EnvironmentModuleGraph {
    return this._moduleGraphs.ssr()
  }

  urlToModuleMap: Map<string, ModuleNode>
  idToModuleMap: Map<string, ModuleNode>
  etagToModuleMap: Map<string, ModuleNode>

  fileToModulesMap: Map<string, Set<ModuleNode>>

  private moduleNodeCache = new DualWeakMap<
    EnvironmentModuleNode,
    EnvironmentModuleNode,
    ModuleNode
  >()

  constructor(moduleGraphs: {
    client: () => EnvironmentModuleGraph
    ssr: () => EnvironmentModuleGraph
  }) {
    this._moduleGraphs = moduleGraphs

    const getModuleMapUnion =
      (prop: 'urlToModuleMap' | 'idToModuleMap') => () => {
        // A good approximation to the previous logic that returned the union of
        // the importedModules and importers from both the browser and server
        if (this._ssr[prop].size === 0) {
          return this._client[prop]
        }
        const map = new Map(this._client[prop])
        for (const [key, module] of this._ssr[prop]) {
          if (!map.has(key)) {
            map.set(key, module)
          }
        }
        return map
      }

    this.urlToModuleMap = createBackwardCompatibleModuleMap(
      this,
      'urlToModuleMap',
      getModuleMapUnion('urlToModuleMap'),
    )
    this.idToModuleMap = createBackwardCompatibleModuleMap(
      this,
      'idToModuleMap',
      getModuleMapUnion('idToModuleMap'),
    )
    this.etagToModuleMap = createBackwardCompatibleModuleMap(
      this,
      'etagToModuleMap',
      () => this._client.etagToModuleMap,
    )
    this.fileToModulesMap = createBackwardCompatibleFileToModulesMap(this)
  }

  getModuleById(id: string): ModuleNode | undefined {
    const clientModule = this._client.getModuleById(id)
    const ssrModule = this._ssr.getModuleById(id)
    if (!clientModule && !ssrModule) {
      return
    }
    return this.getBackwardCompatibleModuleNodeDual(clientModule, ssrModule)
  }

  async getModuleByUrl(
    url: string,
    _ssr?: boolean,