Slow for parsing large arrays containing objects

[marbetschar]

Environment

Browser. Timing tested in latest Firefox.

Description

During experimentation with Jackson-JS we noticed that its JSON deserialization is rather slow for large arrays. The JSON response we parse is an array containing roughly 1200 of the below objects - and parsing takes about 15 seconds.

I'm aware this use case is rather extreme, but unfortunately we are dealing with a legacy API within an enterprise here - so things won't improve somewhen soon.

import {
  JsonIgnoreProperties,
  JsonProperty,
  JsonAlias
} from 'jackson-js';

@JsonIgnoreProperties({ value: [
  'abc',
  'def',
  //... 67 more ignore properties
]})
export class MyModel {

	@JsonProperty()
	@JsonAlias({values: ['xyz']})
	myVarName: number;

	// ... 18 more properties with @JsonProperty and @JsonAlias
}

What you'd like to happen:

I'd love to hear your thoughts on strategies on how to mitigate the parsing impact and/or speed it up.

Alternatives you've considered:

• Obviously, we can cache the result - but 15 secs still seems way too slow.
• Although building a paging into the backend API would solve this, this is very unlikely to happen within a reasonable time span

[badetitou]

Hi @marbetschar

Did you find a way to speed up the deserialization?

[marbetschar]

@badetitou back then we used @marcj/marshal instead of jackson-js. Don't know if it is still maintained though (I no longer work at the project in question).