Share an external module between lazy loaded modules in angular2

Question

My app has components that use a heavy-weight external package (ag-grid, about 1MB) that is provided as an angular2 module ( AgGridModule ). I would like to load this package only when the components using it are required, so my ContentModule and all of its submodules are lazy-loaded. The whole structure looks like this:

However, when I import AgGridModule into both Submodule1 and Submodule3 , it ends up being included in compiled JS twice, making both 1.chunk.js and 3.chunk.js large. I tried importing it into ContentModule , but then the submodules do not recognize the components that are included in AgGridModule , even if I list them in the exports property of ContentModule .

@NgModule({
  imports: [
    ContentRoutingModule,
    SomeOtherModule,
    AgGridModule.withComponents([])
  ],
  exports: [
    // this is the component from AgGridModule that I use
    AgGridNg2
  ]
})
export class ContentModule { }

Is there a way to share a module between lazy loaded modules, or to expose some components of an imported module to lazy loaded children?

UPD: Creating a shared module and importing it into submodules does not help, there are still two chunks with about 1MB each:

UPD2: I solved the problem temporarily by merging Submodule1 and Submodule3 into a single module.

Answer 1

You need to create a SharedAgGridModule :

@NgModule({
  imports: [
    AgGridModule.withComponents([])
  ],
  exports: [
    ContentModule,
    AgGridModule
  ]
})
export class SharedAgGridModule{}

Then you should import this module just for the submodules which uses AgGrid. No need to also import the ContentModule in those submodules, because it is exported in this module

Answer 2

You can use a SharedModule where you import as well as export the AgGridModule . You have to export the complete module AgGridModule and not just the components you use.

Then you can simply import the SharedModule in your Submodule1 and Submodule3 .

Answer 3

We facing the same issue.

2 Solutions

1. Put into ShareModule import and exports it. Sub module import the ShareModule. Basically, ShareModule is without lazy load.
2. Merge to the same path/module lazy load together.