TypeScript types for the format GeoJSON cause compilation errors

[javier-lopez-1s]

Describe the bug
I am using OpenLayers 6.15.1 in an Angular 14 application and when I make use of the GeoJSON format I get the following compilation errors:

ERROR: node_modules/ol/format/GeoJSON.d.ts:2:36 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

2 export type GeoJSONObject = import("geojson").GeoJSON;
node_modules/ol/format/GeoJSON.d.ts:3:37 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

3 export type GeoJSONFeature = import("geojson").Feature;
node_modules/ol/format/GeoJSON.d.ts:4:47 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

4 export type GeoJSONFeatureCollection = import("geojson").FeatureCollection;
node_modules/ol/format/GeoJSON.d.ts:5:38 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

5 export type GeoJSONGeometry = import("geojson").Geometry;
node_modules/ol/format/GeoJSON.d.ts:6:35 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

6 export type GeoJSONPoint = import("geojson").Point;
node_modules/ol/format/GeoJSON.d.ts:7:40 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

7 export type GeoJSONLineString = import("geojson").LineString;
node_modules/ol/format/GeoJSON.d.ts:8:37 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

8 export type GeoJSONPolygon = import("geojson").Polygon;
node_modules/ol/format/GeoJSON.d.ts:9:40 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

9 export type GeoJSONMultiPoint = import("geojson").MultiPoint;
node_modules/ol/format/GeoJSON.d.ts:10:45 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

10 export type GeoJSONMultiLineString = import("geojson").MultiLineString;
node_modules/ol/format/GeoJSON.d.ts:11:42 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

11 export type GeoJSONMultiPolygon = import("geojson").MultiPolygon;
node_modules/ol/format/GeoJSON.d.ts:12:48 - error TS2307: Cannot find module 'geojson' or its corresponding type declarations.

12 export type GeoJSONGeometryCollection = import("geojson").GeometryCollection;

The error disappears if I add the following dependency:
npm install @types/geojson --save-dev

To Reproduce
Steps to reproduce the behavior:

1. ng new test-app
2. cd test-app
3. npm install ol
4. Add lines 2 and 10 to app.component.ts

import { Component } from '@angular/core';
import GeoJSON from 'ol/format/GeoJSON';

@Component({
  selector: 'app-root',
  templateUrl: './app.component.html',
  styleUrls: ['./app.component.scss']
})
export class AppComponent {
  myType = GeoJSON;
  title = 'test-app';
}

5. ng build

Expected behavior
Not to have to add the dependency @types/geojson in order to get rid of the compilation errors. The same issue happens with the format EsriJSON, so I am guessing that the installation of multiple dependencies may potentially be required.

[ahocevar]

It should be enough to move these types from devDependencies to dependencies in package.json. If you'd be able to try this and provide a pull request, it would be appreciated.

[javier-lopez-1s]

Thanks @ahocevar. I was testing your proposal and I have found out that if I compile OpenLayers locally, then I no longer get the error. So a basic Angular application compiles without problems if I do the following:

1. Clone OpenLayers' repository.
2. Compile OpenLayers via npm run build-package. The file package.json is left untouched.
3. Import local version of ol/format/GeoJSON into my Angular application.
4. ng build

However if I import GeoJSON from the OpenLayers' NPM package, then I get the error back again.

[ahocevar]

Sorry, I think my previous comment was confusing. What I wrote was a suggestion to fix the problem in OpenLayers, so it was about OpenLayers's package.json.

[javier-lopez-1s]

I understood your first comment, @ahocevar. I updated OpenLayers' package.json moving @types/geojson and other types from devDependencies to dependencies. My problem was that I couldn't replicate the issue using a local repository because the code generated at build/ol could still find node_modules/@types/geojson. I finally figured out I had to create a local NPM package. After that, I can confirm that moving @types/geojson from devDependencies to dependencies fixes the issue.
From the following devDependencies, I know that the three in bold needs to be moved, but I not sure about the other two. For the pull request to be provided, should I move them all?

• @types/arcgis-rest-api
• @types/geojson
• @types/offscreencanvas
• @types/pbf
• @types/topojson-specification

[ahocevar]

Only those that are used in the public API are needed:

• @types/arcgis-rest-api
• @types/geojson

[javier-lopez-1s]

You get the same error if you import the format TopoJSON, as this is in turn importing types from topojson-specification. In a few days I will create a PR in which I will be moving the 3 items below:

• @types/arcgis-rest-api
• @types/geojson
• @types/topojson-specification

Thanks

[mediafreakch]

Just ended up here and thought it's worth mentioning: There is also a type issue in a dependency of ol called geotiff:

TS2304: Cannot find name 'Source'.

It has been fixed on master there in March, but there haven't been any new releases since.

[ahocevar]

@mediafreakch That's a different issue, which was reported recently in #13924.

[MarkoDotCom]

installing typescript types npm libraries fixed my issue, very similar to yours.

$ npm i @types/geojson

[bjarkehs]

You get the same error if you import the format TopoJSON, as this is in turn importing types from topojson-specification. In a few days I will create a PR in which I will be moving the 3 items below:

• @types/arcgis-rest-api
• @types/geojson
• @types/topojson-specification

Thanks

Did you ever get around to this? Else I'll gladly do it. I just ran into this issue recently as well.

[javier-lopez-1s]

Did you ever get around to this? Else I'll gladly do it. I just ran into this issue recently as well.

I never found the time to create a PR. Please go ahead if you can. Thanks.