Plugin SPI Contract

Module: camel-integration-capability-pluginInterface: org.apache.camel.spi.ContextServicePlugin

Discovery

File: META-INF/services/org.apache.camel.spi.ContextServicePlugin

Content:

ai.wanaku.capability.camel.plugin.CamelIntegrationPlugin

Interface Implementation

package ai.wanaku.capability.camel.plugin;

import org.apache.camel.CamelContext;
import org.apache.camel.spi.ContextServicePlugin;

public class CamelIntegrationPlugin implements ContextServicePlugin {

    /**
     * Called after CamelContext creation, before routes start.
     *
     * Responsibilities:
     * 1. Load configuration from properties/environment
     * 2. Initialize data directory
     * 3. Run initializers (e.g., git clone)
     * 4. Download resources if needed
     * 5. Start gRPC server
     * 6. Register with discovery service
     *
     * @param camelContext The Camel context being initialized
     */
    @Override
    public void load(CamelContext camelContext) {
        // Implementation
    }

    /**
     * Called during CamelContext shutdown.
     *
     * Responsibilities:
     * 1. Deregister from discovery service
     * 2. Stop gRPC server
     * 3. Release resources
     *
     * @param camelContext The Camel context being stopped
     */
    @Override
    public void unload(CamelContext camelContext) {
        // Implementation
    }
}

Configuration Contract

Properties File

Location: Classpath resource camel-integration-capability.properties

Property	Type	Required	Default	Description
registration.url	String	Yes	-	Wanaku registration endpoint URL
registration.announce.address	String	No	auto	Address announced to discovery service
grpc.port	Integer	No	9190	gRPC server port
service.name	String	No	camel	Service name for registration
routes.ref	String	Yes	-	Reference to Camel routes YAML
rules.ref	String	No	-	Reference to exposure rules YAML
token.endpoint	String	No	-	OAuth token endpoint
client.id	String	Yes	-	OAuth client ID
client.secret	String	Yes	-	OAuth client secret
dependencies	String	No	-	Comma-separated dependency refs
repositories	String	No	-	Comma-separated repository URLs
init.from	String	No	-	Git repository URL to clone
data.dir	String	No	/tmp	Data directory path

Environment Variable Override

Each property can be overridden by environment variable. Environment variables take precedence.

Property	Environment Variable
registration.url	REGISTRATION_URL
registration.announce.address	REGISTRATION_ANNOUNCE_ADDRESS
grpc.port	GRPC_PORT
service.name	SERVICE_NAME
routes.ref	ROUTES_PATH
rules.ref	ROUTES_RULES
token.endpoint	TOKEN_ENDPOINT
client.id	CLIENT_ID
client.secret	CLIENT_SECRET
dependencies	DEPENDENCIES
repositories	REPOSITORIES
init.from	INIT_FROM
data.dir	DATA_DIR

Error Handling

Condition	Behavior
Missing required property	Throw IllegalStateException with clear message
Invalid property value	Throw IllegalArgumentException with validation details
Resource download failure	Log error, retry based on configuration
gRPC server start failure	Throw exception, prevent context start
Discovery registration failure	Log warning, continue (non-fatal)

Thread Safety

• load() and unload() are called from Camel context lifecycle thread
• Internal state must be thread-safe for concurrent gRPC requests
• Use volatile or synchronization for mutable state