Plugin Extensibility & `netcdfIOProvider` API

Capella Datascience provides modular extension points allowing third-party plugins to contribute custom protocols, I/O providers, data adapters, and visualization engines.

Extension Point: `org.polarsys.capella.datascience.netcdf.model.netcdfIOProvider`

This extension point enables contributing custom NetCDF file providers for non-standard URI schemes (e.g. AWS S3, Google Cloud Storage, specialized HTTP streams, or encrypted archives).

Schema Specification

<extension-point id="netcdfIOProvider" name="Netcdf IO Provider" schema="schema/netcdfIOProvider.exsd"/>

Contributing a Custom Provider in `plugin.xml`

<extension point="org.polarsys.capella.datascience.netcdf.model.netcdfIOProvider">
    <netcdfIOProvider
        class="com.example.custom.CustomNetcdfIOProvider"
        id="com.example.custom.provider">
    </netcdfIOProvider>
</extension>

Implementing `INetcdfFileProvider`

Your provider class must implement org.polarsys.capella.datascience.netcdf.ncml.extension.INetcdfFileProvider:

package com.example.custom;

import java.util.List;
import org.polarsys.capella.datascience.netcdf.ncml.extension.INetcdfFileProvider;
import ucar.nc2.NetcdfFile;

public class CustomNetcdfIOProvider implements INetcdfFileProvider {

    @Override
    public List<String> getSources() {
        // Return URI prefixes/schemes handled by this provider
        return List.of("s3://", "cdms3://", "mycustom://");
    }

    @Override
    public NetcdfFile getNetcdfFile(String location) {
        // Resolve and return a UCAR NetcdfFile instance for the location
        return CustomStorageClient.openNetcdf(location);
    }
}

Core Utility APIs

Class	Key Methods	Purpose
`NcmlUtils.instance`	`getNetCDF(EObject)` `getVariableExt(NetcdfType, String)` `resolveDimensionsExt(VariableType)` `getAttributeExt(VariableType, String)`	Fast navigation, query, and dimension resolution on EMF NetCDF/NcML models.
`NetcdfNativeRegistry.instance`	`get(String location)` `register(String location, NetcdfFile)` `unregister(String location)`	Thread-safe caching of native UCAR `NetcdfFile` instances with automatic workspace resource change tracking.
`NCConfigResourceUtils`	`loadConfigBook(File)` `saveConfigBook(NCVisualizationConfigBook, File)` `saveConfigToFile(NCVisualizationConfig, File)`	Loading, saving, and resolving proxies for `.ncconfig` books without dangling external references.
`ImageUtils.instance`	`computeImageFromDimsAndPaletteIfAnyWithExtraInfo(...)` `getInterpolatedColorPaletteIfNecessary(depth, pInfo)` `getPalette(paletteId)`	Color palette lookup, gradient interpolation, missing value masking, and SWT `ImageData` generation.

Plugin Extensibility & netcdfIOProvider API

Extension Point: org.polarsys.capella.datascience.netcdf.model.netcdfIOProvider