unknown type in cursor: [object]

[mividtim]

Hi there! This library is awesome. It's working great for most use cases I've encountered. However, I'm getting a weird error from the internals of the library occasionally when querying against test fixtures that were inserted into my local database by other tests prior to my test running. The column on which I'm trying to paginate has the PG type timestamp.

The entity is defined as follows:

    @Column({
        type: 'timestamp',
        nullable: true,
    })
    videoDisplayTime!: Date | null;

Here's the error coming out of the test run, with internals snipped out.

    Error: unknown type in cursor: [object]Mon Nov 23 2020 18:23:15 GMT+0000 (Coordinated Universal Time),at Object.encodeByType ([snip]/node_modules/typeorm-cursor-pagination/src/utils.ts:23:13),at payload.paginationKeys.map ([snip]/node_modules/typeorm-cursor-pagination/src/Paginator.ts:178:21),at Array.map (<anonymous>),at Paginator.encode ([snip]/node_modules/typeorm-cursor-pagination/src/Paginator.ts:176:41),at Paginator.<anonymous> ([snip]/node_modules/typeorm-cursor-pagination/src/Paginator.ts:92:35),at Generator.next (<anonymous>),at fulfilled ([snip]/node_modules/typeorm-cursor-pagination/lib/Paginator.js:5:58),at process._tickCallback (internal/process/next_tick.js:68:7)
    --
    body: {
      "status": 500,
      "errorName": "Error",
      "message": "unknown type in cursor: [object]Mon Nov 23 2020 18:23:15 GMT+0000 (Coordinated Universal Time)",
      "stack": [
        "at Object.encodeByType ([snip]/node_modules/typeorm-cursor-pagination/src/utils.ts:23:13)",
        "at payload.paginationKeys.map ([snip]/node_modules/typeorm-cursor-pagination/src/Paginator.ts:178:21)",
        "at Array.map (<anonymous>)",
        "at Paginator.encode ([snip]/node_modules/typeorm-cursor-pagination/src/Paginator.ts:176:41)",
        "at Paginator.<anonymous> ([snip]/node_modules/typeorm-cursor-pagination/src/Paginator.ts:92:35)",
        "at Generator.next (<anonymous>)",
        "at fulfilled ([snip]/node_modules/typeorm-cursor-pagination/lib/Paginator.js:5:58)",
        "at process._tickCallback (internal/process/next_tick.js:68:7)"
      ]
    }

Any ideas on what I we may be doing wrong would be greatly appreciated!

[benjamin658]

Hi @mividtim , thanks for reporting the issue.

The library use Reflect.getMetadata(design:type...) to evaluate the type of specific pagination keys before encode a cursor.

I have tried to reproduce an issue, however everything is working fine:

import "reflect-metadata";
import { Entity, Column } from 'typeorm';

@Entity()
class Demo {
  @Column({
    type: 'timestamp',
    nullable: true,
  })
  videoDisplayTime!: Date | null;
}

console.log(Reflect.getMetadata('design:type', Demo.prototype, 'videoDisplayTime').name.toLowerCase()); // date

Could you provide more information about your runtime environment (version of typescript, ts-node, etc...)?

[mividtim]

Hi there. Thanks for getting back so quickly. We're running "typescript": "3.7.2", "typeorm": "0.2.20", "ts-node": "8.4.1", "typeorm-cursor-pagination": "0.4.1", and typeorm-naming-strategies": "1.1.0". We use SnakeNamingStrategy for our table and column names... Not that I think that's relevant. We run all of this in the context of NestJS 6.8.4.

[mividtim]

NodeJS 10.15.3, yarn 1.16.0, and postgres 11.2.

[benjamin658]

I have tried the same version of these dependencies, and everything is working fine.

Could you share a piece of code that using this lib?

[mividtim]

I set up a contrived example. I believe the issue is with the naming strategy. This pagination library doesn't seem to use the naming strategy set in the TypeOrm configuration to derive proper column names for its pagination keys.

https://github.com/mividtim/pagination-test

Repro steps:

• Clone the repo.
• Run yarn or npm install.
• Create a local DB and a PG user/password for the sample to own.
• Copy sample.env to .env.
• Edit the values in .env to point to your local DB
• Run yarn start:dev
• Hit http://localhost:3000 to generate the DB table. The output should be an object with an empty construed array.
• Run yarn migration:up to populate the construed table with some test data.
• Refresh http://localhost:3000 to see the new data (7 values in the construed property)
• Hit http://localhost:3000?limit=3 to run into the error.

[benjamin658]

@mividtim thanks for the steps to reproduce an error.

I will try to fix it in my free time, if you already know how to fix it, please give me some hints or feel free to send a PR.

[mabilbao]

Hey guys! it's happening exactly the same. Any updates about it?

Thank you! 😄

[mividtim]

Hey there! No update. I basically skipped cursor pagination and am using page lengths and numbers, which is inferior, but workable if your data doesn't move fast. I wish this worked, but I didn't invest the time to make it work.

[judehunter]

it's a shame this is still an issue...
unfortunately this makes this library unusable to me

[benjamin658]

Hey guys, sorry for the late reply.

@mividtim @judehunter actually I have already fixed the naming strategy issue a few months ago,
if you don't mind giving it a try, please upgrade to v0.6.0.

cc22879
c2dcc64

#19

[judehunter]

@benjamin658 at the time of my comment (9 days ago), I was using the latest version (which I believe was 0.6.0)
It was still an issue for me.

I might be able to provide some more detail later, but I have since switched to limit/offset pagination instead.

[benjamin658]

Hi @judehunter, thanks for your help.

Since I still cannot reproduce the issue, it would be great if you can provide some more details.

By the way, PR for fixing this issue is welcome.

[benjamin658]

Hi @mabilbao @mividtim @judehunter @miohtama ,

I think I finally found the root cause, it's ts-node issue: TypeStrong/ts-node#511

For some reason ts-node Reflect.getMetadata of Date reflection is broken, it returns Object instead of Date.
Currently you can use the --type-check flag to workaround if you are using ts-node to run you app.

I will try to fix the function

typeorm-cursor-pagination/src/utils.ts

Line 9 in 28f35cb

export function encodeByType(type: string, value: any): string | null {

to handle unexpected reflection issue.

[mividtim]

We use tsc to compile, and run with node itself, and I was seeing object from the reflect call...

[benjamin658]

Sorry to keep you waiting so long.

I just fixed the issue, please upgrade to v0.6.1.

[Snowdrop-ctrl]

Error: unknown type in cursor: [boolean]true
at Object.encodeByType (/home/nitesh/WebstormProjects/tw-backend/node_modules/typeorm-cursor-pagination/lib/utils.js:36:11)
at /home/nitesh/WebstormProjects/tw-backend/dist/utils/paginator/pagination.js:113:35
at Array.map ()
at Paginator.encode (/home/nitesh/WebstormProjects/tw-backend/dist/utils/paginator/pagination.js:111:14)
at Paginator.paginate (/home/nitesh/WebstormProjects/tw-backend/dist/utils/paginator/pagination.js:45:41)
at processTicksAndRejections (internal/process/task_queues.js:95:5)
at async PostsService.getAllPosts (/home/nitesh/WebstormProjects/tw-backend/dist/services/posts.service.js:159:56)
at async PostsController.all (/home/nitesh/WebstormProjects/tw-backend/dist/controllers/posts.controller.js:14:42)

any solution for this boolean

[byteHulk]

it's a shame this is still an issue...
version 0.10.0

[mividtim]

@byteHulk This might get you a bit further down the road... https://github.com/mividtim/typeorm-cursor-pagination

[mividtim]

Hmm, maybe not. I don't see my commit that fixed the issue. :-( I long lost that computer.

[kprice-ae]

Having the same issue mentioned in #16 (comment)

does not work with booleans or enum types