Runtime error: feature referenced out of range key

[doubotis]

Describe the bug On some specific PBF files, the Android and iOS native lib crashes with a std::runtime error :

feature referenced out of range key

I attached a sample of a PBF file that triggers the crash : 5512.pbf.zip. If you need the MBTiles that originated this PBF file and the styling, I can host it. The PBF file is reported as a valid Vector Mapbox Tile. This file is read and handled without any problem by the Javascript library maplibre-gl-js.

To Reproduce

1. Go to the location that leads to this PBF file. Coordinates: 50.625487, 5.570648 (50°37'31.8"N 5°34'14.3"E)
2. Zoom to level 18.
3. See crash.

Expected behavior App still working nicely and displaying maps.

Platform information (please complete the following information):

• OS: iOS16+ and Android 10+, not tested before these versions.
• Platform: iOS/Android (native)
• Version: org.maplibre.gl:android-sdk:9.6.0

Additional context It seems the issue is bound to some duplicated properties on some PBF files, but I can't tell how to solve the issue. The reported crash message seems to be located here. I have found some evidences on this bug report too. Sadly, i struggle to decide if I have to solve the issue from Maplibre GL Native or if this is the MBTiles's fault. For reference, I filled the issue in openmaptiles-tools github repos too (as the MBTiles was generated from these tools).

[xabbu42]

I reported the linked bug and also authored a possible fix (with test) in a pull request. Sadly the pull request was never applied. All vector tiles generated with postgis are potentially affected, depending of the parallelization of the query. Currently we artificially reduce parallel query execution in our tools to work around the bug. I'm very interested to get a proper fix into maplibre-gl-native as this would allow us to remove that limitation.

As described in the bug report there are some performance implications with the possible fixes.

The standard discourages but allows such tiles, so Maplibre GL Native should either support them or document that it uses a stricter standard. Maplibre GL JS on the other hand handles such tiles without problems, so for feature compatibility Native should as well.

[ovivoda]

@xabbu42 can you please point me to the PR that should have fixed this problem?

[xabbu42]

https://github.com/mapbox/vector-tile/pull/56 or https://github.com/mapbox/vector-tile/pull/53 should both fix this issue (from memory and what I wrote in https://github.com/mapbox/vector-tile/issues/55, I did not recheck any of this). The two pull requests do have different performance implications.

[doubotis]

All vector tiles generated with postgis are potentially affected, depending of the parallelization of the query.

I can confirm this statement. For every MBTiles creation attempt, issues don't occur in the same place. Sometimes, vector tiles generated at zoom level 4-6 got the issue, leading to the crash of the app instantly.

Currently we artificially reduce parallel query execution in our tools...

Besides the fact I am greatly interested by an update of Maplibre GL Native to handle duplicate property keys, can you explain more in details how do you reduce the parallel query execution on MBTiles generation, and how much this impacts generation time ?

More specifically, which configuration files are needed to modify to reduce parallel query execution ?

Thanks!

[xabbu42]

We already use a custom function in all our mbtiles queries and we just removed the "parallel save" declaration in that function (https://www.postgresql.org/docs/current/parallel-safety.html) which has the side effect of inhibiting parallel execution exactly where we currently don't want it. A clean way to achieve a similar result may be https://www.postgresql.org/docs/current/runtime-config-resource.html#GUC-MAX-PARALLEL-WORKERS-PER-GATHER

[AJJackGIS]

I'm using node:v-5.2.0 and find vector-tile hash id is bc2f7f44cdb0d9af2b282ea4a755f85a13ba713a , the latest submission records show that this problem has been solved, is it possible to fix this problem by compiling the latest code ?

[CQGISer]

The use of GDAL to make mvt will still appear"feature referenced out of range key", Is there a way to solve the problem?

[nathreed]

mapbox/vector-tile#56 or mapbox/vector-tile#53 should both fix this issue (from memory and what I wrote in mapbox/vector-tile#55, I did not recheck any of this). The two pull requests do have different performance implications.

@louwers would MapLibre be open to forking https://github.com/mapbox/vector-tile to apply one of these two fixes for this issue? The license seems compatible and the upstream project appears to be abandoned/have very little activity, and in any case little interest in merging either of the proposed fixes.

[louwers]

@nathreed Absolutely!

Do you want to kick off the process, or shall I do it? The New Repository Checklist is here: https://github.com/maplibre/maplibre/issues/new/choose

[nathreed]

@louwers I went ahead and opened an issue to kick off discussion about this.

[acalcutt]

@louwers Should I cherry pick the vector-tile change to opengl-2 for node? I seem to recall we had worked around a few errors caused by vector-tile already, but I would imagine some issues still exist. I am having trouble finding the threads right now but I will look.

[louwers]

@acalcutt Sounds like a good idea.

[acalcutt]

For testing with node, does anyone have the original mbtiles and style file I could look at and try in tileserver-gl? i see there is a pbf but the mbtiles would be much easier to test with.