package com.espertech.esperio.http;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.client.EventType;
import com.espertech.esper.core.service.EPServiceProviderSPI;
import com.espertech.esper.epl.core.MethodResolutionServiceImpl;
import com.espertech.esper.event.EventBeanManufactureException;
import com.espertech.esper.event.EventBeanManufacturer;
import com.espertech.esper.event.EventTypeSPI;
import com.espertech.esper.event.WriteablePropertyDescriptor;
import com.espertech.esper.util.SimpleTypeParser;
import com.espertech.esper.util.SimpleTypeParserFactory;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.*;
import org.apache.http.protocol.HttpContext;
import org.apache.http.protocol.HttpRequestHandler;
import java.io.IOException;
import java.io.UnsupportedEncodingException;
import java.util.*;
public class EsperHttpRequestHandler implements HttpRequestHandler {
private static Log log = LogFactory.getLog(EsperHttpRequestHandler.class);
private final EPServiceProviderSPI engineSPI;
private final MethodResolutionServiceImpl methods;
private final Map<String, EsperHttpRequestCacheEntry> streamCache = new HashMap<String, EsperHttpRequestCacheEntry>();
public EsperHttpRequestHandler(final EPServiceProviderSPI engineSPI) {
super();
this.engineSPI = engineSPI;
this.methods = new MethodResolutionServiceImpl(engineSPI.getEngineImportService(), engineSPI.getTimeProvider());
}
public void handle(
final HttpRequest request,
final HttpResponse response,
final HttpContext context) throws HttpException, IOException {
String method = request.getRequestLine().getMethod().toUpperCase(Locale.ENGLISH);
if (!method.equals("GET") && !method.equals("HEAD") && !method.equals("POST")) {
throw new MethodNotSupportedException(method + " method not supported");
}
response.setStatusCode(HttpStatus.SC_OK);
String target = request.getRequestLine().getUri();
try {
Map<String, String> parameters = parseTarget(target);
handle(parameters);
}
catch (Throwable t) {
log.error("Error processing Http GET request target '" + target + "' :" + t.getMessage(), t);
}
}
private void handle(Map<String, String> parameters) {
String eventTypeName = parameters.get("stream");
EsperHttpRequestCacheEntry cacheEntry = streamCache.get(eventTypeName);
if (cacheEntry == null) {
cacheEntry = makeCacheEntry(eventTypeName);
streamCache.put(eventTypeName, cacheEntry);
}
if (cacheEntry == null) {
return;
}
Object[] values = new Object[cacheEntry.getParsers().length];
for (int i = 0; i < cacheEntry.getParsers().length; i++) {
String value = parameters.get(cacheEntry.getWritableProperties()[i].getPropertyName());
if (value == null) {
continue;
}
values[i] = cacheEntry.getParsers()[i].parse(value);
}
EventBean theEvent = cacheEntry.getEventBeanManufacturer().make(values);
engineSPI.getEPRuntime().sendEvent(theEvent);
}
private EsperHttpRequestCacheEntry makeCacheEntry(String eventTypeName) {
EventType eventType = engineSPI.getEventAdapterService().getExistsTypeByName(eventTypeName);
if (eventType == null) {
log.info("Event type by name '" + eventTypeName + "' not found.");
return null;
}
if (!(eventType instanceof EventTypeSPI)) {
log.info("Event type by name '" + eventTypeName + "' is not writable.");
return null;
}
EventTypeSPI eventTypeSPI = (EventTypeSPI) eventType;
Set<WriteablePropertyDescriptor> writablesSet = engineSPI.getEventAdapterService().getWriteableProperties(eventTypeSPI, false);
List<WriteablePropertyDescriptor> writablePropertiesList = new ArrayList<WriteablePropertyDescriptor>();
List<SimpleTypeParser> parserList = new ArrayList<SimpleTypeParser>();
for (WriteablePropertyDescriptor writableDesc : writablesSet)
{
SimpleTypeParser parser = SimpleTypeParserFactory.getParser(writableDesc.getType());
if (parser == null) {
log.debug("No parser found for type '" + writableDesc.getType() + "'");
continue;
}
writablePropertiesList.add(writableDesc);
parserList.add(parser);
}
WriteablePropertyDescriptor[] writableProperties = writablePropertiesList.toArray(new WriteablePropertyDescriptor[writablePropertiesList.size()]);
SimpleTypeParser[] parsers = parserList.toArray(new SimpleTypeParser[parserList.size()]);
EventBeanManufacturer eventBeanManufacturer;
try {
eventBeanManufacturer = engineSPI.getEventAdapterService().getManufacturer(eventType, writableProperties, methods.getEngineImportService(), false);
}
catch (EventBeanManufactureException e) {
log.info("Unable to create manufacturer for event type: " + e.getMessage(), e);
return null;
}
return new EsperHttpRequestCacheEntry(eventBeanManufacturer, writableProperties, parsers);
}
private HashMap<String, String> parseTarget(String search) throws UnsupportedEncodingException {
int start = search.indexOf('?');
if (start == -1) {
return new HashMap<String, String>();
}
String parameters = search.substring(start + 1, search.length());
return splitParams(parameters);
}
private HashMap<String, String> splitParams(String search) throws UnsupportedEncodingException {
HashMap<String, String> map = new HashMap<String, String>();
String parameters[] = search.split("&");
for (String param : parameters) {
String temp[] = param.split("=");
if (temp.length != 2) {
continue;
}
map.put(temp[0], java.net.URLDecoder.decode(temp[1], "UTF-8"));
}
return map;
}
}