GroundPolylinePrimitive._initializeTerrainHeightsWorker fails when app is served via a proxied domain

[madole]

GroundPolylinePrimitive._initializeTerrainHeightsWorker tries to load in the approximateTerrainHeights.json from a relative path.

GroundPolylinePrimitive.js

ApproximateTerrainHeights.initialize('../Assets/approximateTerrainHeights.json')

This then calls the buildModuleUrl function with that path before passing it to Resource.fetchJson

ApproximateTerrainHeights.js

ApproximateTerrainHeights._initPromise = Resource.fetchJson(buildModuleUrl(url)).then(function(json) {
            ApproximateTerrainHeights._terrainHeights = json;
        });

buildModuleUrl first does a check to see if it's running in node by checking typeof document === 'undefined' and if true, it just returns moduleID.

When inside a web worker, document is undefined and the relative path is returned as it would be in node. This is fine when the code is being accessed on the same domain as it's being served on.

But when you proxy the app, the relative path becomes http://proxied-url.com/../Assets/approximateTerrainHeights.json which doesn't exist as the JSON is being served on a different domain and so the Resource.fetchJson blows up.

[hpinkos]

Thanks for catching this before it went out in the release @madole! I've opened up a pull request fixing it here: #6715

[likangning93]

@madole @hpinkos does this also apply to non-worker requests for the terrain heights JSON too?
Seems like that would be asking for just http://proxied-url.com/Assets/approximateTerrainHeights.json, which presumably also doesn't exist.

[EDIT] ah I also don't know how buildModuleUrl works, so it might be getting handled in there already.

[madole]

yeah it's handled in buildModuleUrl, because the non-worker context would have document in scope, it'll build the path using CESIUM_BASE_PATH so it's just the workers that have the issue

[mramato]

Replaced by #6720 (though I'm going to keep this branch around until that one gets merged).

[mramato]

Whoops, meant to comment on the PR not the issue.