Platform: ngrx-data delete error

[chobijaeyu]

Goods day.
I've been stuck here for a few days.And i really need some help.
I'm trying to use ngrx/data,it's working fine when add,update,get. but it gets error when delete.(not 100% happen)

Minimal reproduction of the bug/regression with instructions:

fontend:https://github.com/chobijaeyu/todoListAngular backend:https://github.com/chobijaeyu/todoListGin

service:

export class TodoService extends EntityCollectionServiceBase<Todo> {

  constructor(serviceElementsFactory: EntityCollectionServiceElementsFactory) {
    super("Todo", serviceElementsFactory);
  }

}

component.ts:

 deleteTodo(e: Event, todo: Todo) {
    e.stopPropagation()
    this.todoservice.delete(todo) 
// I tried this.todoservice.delete(todo.id)  same error
  }

error:

data.js:8106 TypeError: Cannot assign to read only property 'changeType' of object '[object Object]'
    at data.js:5990
    at Array.reduce (<anonymous>)
    at EntityChangeTrackerBase.trackDeleteMany (data.js:5968)
    at EntityChangeTrackerBase.trackDeleteOne (data.js:6023)
    at EntityCollectionReducerMethods.saveDeleteOne (data.js:6711)
    at entityCollectionReducer (data.js:7553)
    at EntityCacheReducerFactory.applyCollectionReducer (data.js:8025)
    at EntityCacheReducerFactory.entityCacheReducer (data.js:7749)
    at store.js:418
    at combination (store.js:306)

or

data.js:8106 TypeError: Cannot add property skip, object is not extensible
    at EntityCollectionReducerMethods.saveDeleteOne (data.js:6707)
    at entityCollectionReducer (data.js:7553)
    at EntityCacheReducerFactory.applyCollectionReducer (data.js:8025)
    at EntityCacheReducerFactory.entityCacheReducer (data.js:7749)
    at store.js:435
    at combination (store.js:323)
    at store.js:1282
    at store.js:403
    at computeNextEntry (store-devtools.js:999)
    at recomputeStates (store-devtools.js:1052)

Expected behavior:

what i expecte is delete item remote and local store.
actually it's did delete item remote,delete request return 200 even got this TypeError.

Versions of NgRx, Angular, Node, affected browser(s) and operating system(s):

Angular CLI: 9.1.7
Node: 14.3.0
OS: darwin x64

Angular: 9.1.9
... animations, common, compiler, compiler-cli, core, forms
... language-service, localize, platform-browser
... platform-browser-dynamic, router, service-worker
Ivy Workspace: Yes

Package                           Version
-----------------------------------------------------------
@angular-devkit/architect         0.901.7
@angular-devkit/build-angular     0.901.7
@angular-devkit/build-optimizer   0.901.7
@angular-devkit/build-webpack     0.901.7
@angular-devkit/core              9.1.7
@angular-devkit/schematics        9.1.7
@angular/cdk                      9.2.4
@angular/cli                      9.1.7
@angular/flex-layout              9.0.0-beta.29
@angular/material                 9.2.4
@ngtools/webpack                  9.1.7
@schematics/angular               9.1.7
@schematics/update                0.901.7
rxjs                              6.5.5
typescript                        3.8.3
webpack                           4.42.0

    "@ngrx/data": "^9.2.0",
    "@ngrx/effects": "^9.2.0",
    "@ngrx/entity": "^9.2.0",
    "@ngrx/router-store": "^9.2.0",
    "@ngrx/schematics": "^9.2.0",
    "@ngrx/store": "^9.2.0",
    "@ngrx/store-devtools": "^9.2.0",

donated $20,thanks for your brilliant works.

[ionutkosteea]

Are there any news in regards to this issue. Will it be fixed soon?

[MHzarini]

i have same issue here, any updates?

[rexebin]

i have same issue here, any updates?

ditto..

This only happens when I specifically use addOneToCache(entity) after add entity.

I have this signalR service getting notifications on data changes on push, it process the notification and update cache if required. When a child entity is being created together with its parent, I need to manually add the child to its cache so that all client get updated.

I also find a very wired bug, if I subscribe to getByKey() and the returned entity in the stream of Observable is an old cached one instead of the one returned from remote! If I call the api via httpclient the new one returns correctly, but then I need to manually handle updateOneInCache and addOneToCache which leads to above delete problem.

[rexebin]

I went through the code base and found that in https://github.com/ngrx/platform/blob/master/modules/data/src/dispatchers/entity-dispatcher-base.ts, the actions ends with shareReplay(1). I had an exchange with @alex-okrushko and we agreed that shareReplay(1) is for sharing something for the lifespan of the entire application. With shareReplay(1), it keeps live even there is no subscribers.

Therefore I would suggest use shareReplay({buffSize:1, refCount:true}) in places of shareReplay(1). @brandonroberts

[brandonroberts]

That sounds reasonable to me. If you could add a test to verify the fix that would be great

[brandonroberts]

Someone still want to put in a PR for this fix?

[rexebin]

Not sure how to write a test for this, haven’t learned the dark magic behind shareReplay yet. I manually put a finally operator in the pipe and I could see shareReplay does not get destroyed when all subscriptions were unsubscribed. Definitely need to be very careful using this operator. Always set refcount to true, unless it is intended to stay throughout the lifetime of the app.

[rexebin]

The thing is, if adding refcount to these shareReplay operators in the code base doesn’t break current tests, I would vote for it.

[RepentAndBelieveTheGospel]

I've encountered this same issue, as described by @rexebin.

If I use addOneToCache after add, I get this:
TypeError: Cannot add property skip, object is not extensible
at EntityCollectionReducerMethods.saveDeleteOne (entity-collection-reducer-methods.ts:493)

If I use upsertOneInCache after add, I get this:
TypeError: Cannot assign to read only property 'changeType' of object '[object Object]'
at entity-change-tracker-base.ts:457

I've also noticed that if I use add then delete, it works. If I call add more than once consecutively (like in a file upload), then use delete, it crashes as shown above.