ApiUtils.java

package ddth.dasp.common.utils;

import java.io.PrintWriter;
import java.io.StringWriter;
import java.io.Writer;
import java.util.HashMap;
import java.util.Map;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import ddth.dasp.common.DaspGlobal;
import ddth.dasp.common.api.IApiGroupHandler;
import ddth.dasp.common.api.IApiHandler;
import ddth.dasp.common.logging.ProfileLogEntry;
import ddth.dasp.common.logging.ProfileLogger;
import ddth.dasp.common.osgi.IOsgiBootstrap;

public class ApiUtils {

	private final static Logger LOGGER = LoggerFactory
			.getLogger(ApiUtils.class);

	/**
	 * Convenient method to create an API's result map.
	 * 
	 * @param status
	 * @param message
	 * @return
	 */
	public static Map<Object, Object> createApiResult(int status, Object message) {
		Map<Object, Object> result = new HashMap<Object, Object>();
		result.put(IApiHandler.RESULT_FIELD_STATUS, status);
		result.put(IApiHandler.RESULT_FIELD_MESSAGE, message);
		return result;
	}

	/**
	 * Convenient to execute an API.
	 * 
	 * @param moduleName
	 * @param functionName
	 * @param apiParams
	 * @param authKey
	 * @param remoteAddr
	 * @return
	 */
	public static Object executeApi(String moduleName, String functionName,
			Object apiParams, String authKey, String remoteAddr) {
		return executeApi(moduleName, functionName, apiParams, authKey,
				remoteAddr, false);
	}

	/**
	 * Convenient to execute an API.
	 * 
	 * @param moduleName
	 * @param functionName
	 * @param apiParams
	 * @param authKey
	 * @param remoteAddr
	 * @param debugOutput
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public static Object executeApi(String moduleName, String functionName,
			Object apiParams, String authKey, String remoteAddr,
			boolean debugOutput) {
		long timestampStart = System.nanoTime();
		IOsgiBootstrap osgiBootstrap = DaspGlobal.getOsgiBootstrap();
		Object result;
		try {
			Map<String, String> filter = new HashMap<String, String>();
			filter.put(IApiHandler.PROP_MODULE, moduleName);
			filter.put(IApiHandler.PROP_API, functionName);
			IApiHandler apiHandler = osgiBootstrap.getService(
					IApiHandler.class, filter);
			if (apiHandler != null) {
				result = apiHandler.callApi(apiParams, authKey, remoteAddr);
			} else {
				filter.remove(IApiHandler.PROP_API);
				IApiGroupHandler apiGroupHandler = osgiBootstrap.getService(
						IApiGroupHandler.class, filter);
				if (apiGroupHandler != null) {
					result = apiGroupHandler.handleApiCall(functionName,
							apiParams, authKey, remoteAddr);
				} else {
					if ("stats".equals(moduleName) && functionName == null) {
						// special handler for displaying api statistic
						// TODO
						Map<Object, Object> res = ApiUtils.createApiResult(
								IApiHandler.RESULT_CODE_NOT_IMPLEMETED,
								"No handler for [" + moduleName + "/"
										+ functionName + "]!");
						result = res;
					} else {
						Map<Object, Object> res = ApiUtils.createApiResult(
								IApiHandler.RESULT_CODE_NOT_IMPLEMETED,
								"No handler for [" + moduleName + "/"
										+ functionName + "]!");
						result = res;
					}
				}
			}
		} catch (Exception ex) {
			LOGGER.error(ex.getMessage(), ex);
			Map<Object, Object> res = ApiUtils.createApiResult(
					IApiHandler.RESULT_CODE_ERROR, ex.getMessage());
			Writer writer = new StringWriter();
			PrintWriter printWriter = new PrintWriter(writer);
			ex.printStackTrace(printWriter);
			Throwable rootCause = ex.getCause();
			while (rootCause != null) {
				rootCause.printStackTrace(printWriter);
				rootCause = rootCause.getCause();
			}
			res.put("stacktrace", writer.toString());
			result = res;
			printWriter.close();
		} finally {
		}

		if (result instanceof Map) {
			Map<Object, Object> temp = (Map<Object, Object>) result;
			Map<Object, Object> debug = new HashMap<Object, Object>();
			temp.put("debug", debug);

			long timestampEnd = System.nanoTime();
			debug.put("execution_time_millis",
					(timestampEnd - timestampStart) / 1e6);

			if (debugOutput || true) {
				ProfileLogEntry profileLog = ProfileLogger.get();
				if (profileLog != null) {
					debug.put("profiling", profileLog.getProfiling());
				}
			}
		}
		return result;
	}
}