Extension Points

The plugin defines custom extension points that allow third-party plugins to extend its functionality. All extension points are dynamic (support runtime loading/unloading).

rootProvider

Interface: io.kanro.idea.plugin.protobuf.lang.root.ProtobufRootProvider

Provides import root directories for proto file resolution. When the plugin encounters an import statement, it queries all registered root providers to find the imported file.

Built-in Providers

Provider	Source
ModuleSourceRootProvider	Module source directories marked as proto roots
LibraryRootProvider	JAR libraries containing .proto files
EmbeddedRootProvider	Google's standard proto definitions bundled with the plugin
DecompiledRootProvider	Proto files reconstructed from compiled descriptors
GoRootProvider	Go module proto paths (from golang integration)

Usage

<extensions defaultExtensionNs="io.kanro.idea.plugin.protobuf">
    <rootProvider implementation="com.example.MyRootProvider"/>
</extensions>

class MyRootProvider : ProtobufRootProvider {
    override fun roots(context: ProtobufRootProviderContext): List<VirtualFile> {
        // Return directories containing .proto files
    }
}

symbolReferenceProvider

Interface: io.kanro.idea.plugin.protobuf.lang.psi.feature.ProtobufSymbolReferenceProvider

Provides custom symbol references beyond standard proto references. Used by AIP to resolve resource type names in string literals.

Built-in Providers

• AipResourceReferenceProvider — Resolves (google.api.resource_reference) type strings

indexProvider

Interface: io.kanro.idea.plugin.protobuf.lang.psi.feature.ProtobufIndexProvider

Contributes index entries for proto elements, enabling navigation between proto definitions and generated code.

Built-in Providers

Provider	Purpose
JavaIndexProvider	Index Java generated class names
GoIndexProvider	Index Go generated type names
SisyphusIndexProvider	Index Sisyphus Kotlin type names

Usage

class MyIndexProvider : ProtobufIndexProvider {
    override fun buildIndex(element: ProtobufElement): Map<StubIndexKey<*, *>, List<String>> {
        // Return index entries for this element
    }
}

stubExternalProvider

Interface: io.kanro.idea.plugin.protobuf.lang.psi.feature.ProtobufStubExternalProvider

Provides additional external data to be stored alongside PSI stubs. Used by Java integration to cache Java option values.

Built-in Providers

• FileJavaOptionsProvider — Extracts java_package, java_outer_classname, java_multiple_files options

protocPlugin

Interface: io.kanro.idea.plugin.protobuf.compile.ProtobufCompilerPlugin

Hooks into the protobuf compilation process, allowing custom code generation plugins.

Built-in Compilers

Compiler	Purpose
FileCompiler	File-level compilation
MessageCompiler	Message type compilation
EnumCompiler	Enum type compilation
MessageFieldCompiler	Message field compilation
MessageMapEntryCompiler	Map entry type compilation
MessageMapFieldCompiler	Map field compilation
MessageOneofCompiler	Oneof field compilation
EnumValueCompiler	Enum value compilation
ServiceCompiler	Service compilation
ServiceMethodCompiler	Service method compilation