package com.espertech.esperio.http;
import com.espertech.esper.adapter.BaseSubscription;
import com.espertech.esper.client.EventBean;
import com.espertech.esper.event.EventTypeSPI;
import com.espertech.esper.event.EventBeanReader;
import com.espertech.esper.filter.FilterHandleCallback;
import com.espertech.esper.util.PlaceholderParser;
import com.espertech.esper.util.PlaceholderParseException;
import com.espertech.esperio.http.core.URIUtil;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.HttpClient;
import org.apache.http.impl.client.BasicResponseHandler;
import org.apache.http.impl.client.DefaultHttpClient;
import javax.naming.ConfigurationException;
import java.util.*;
import java.net.URI;
import java.net.URISyntaxException;
import java.io.IOException;
public class EsperIOHTTPSubscription extends BaseSubscription
{
private static Log log = LogFactory.getLog(EsperIOHTTPSubscription.class);
private String uuid = UUID.randomUUID().toString();
private final String stream;
private final URI uriPrecompiled;
private final HttpClient httpclient;
private final ResponseHandler<String> responseHandler;
private final List<PlaceholderParser.Fragment> fragments;
public EsperIOHTTPSubscription(String stream, String uriWithReplacements) throws URISyntaxException, ConfigurationException {
this.httpclient = new DefaultHttpClient();
this.responseHandler = new BasicResponseHandler();
this.stream = stream;
if (uriWithReplacements.indexOf("${") == -1) {
uriPrecompiled = new URI(uriWithReplacements);
fragments = null;
}
else {
try {
fragments = PlaceholderParser.parsePlaceholder(uriWithReplacements);
}
catch (PlaceholderParseException e) {
throw new ConfigurationException("URI with placeholders '" + uriWithReplacements + "' could not be parsed");
}
uriPrecompiled = null;
}
}
public void matchFound(EventBean theEvent, Collection<FilterHandleCallback> allStmtMatches)
{
EventTypeSPI spi = (EventTypeSPI) theEvent.getEventType();
EventBeanReader reader = spi.getReader();
Object[] props = reader.read(theEvent);
String names[] = spi.getPropertyNames();
Map<String, String> parameters = formPairs(names, props, "stream", stream);
URI requestURI;
if (uriPrecompiled != null) {
requestURI = URIUtil.withQuery(uriPrecompiled, parameters);
}
else {
String uri = formURI(parameters, fragments);
try {
requestURI = new URI(uri);
} catch (URISyntaxException e) {
log.error("Incorrect URI generated: " + e.getMessage(), e);
return;
}
}
if (log.isDebugEnabled()) {
log.debug("Requesting from URI " + requestURI);
}
HttpGet httpget = new HttpGet(requestURI);
try {
httpclient.execute(httpget, responseHandler);
} catch (IOException e) {
log.warn("Error executing request:" + e.getMessage());
}
}
private String formURI(Map<String, String> parameters, List<PlaceholderParser.Fragment> fragments) {
StringBuilder buf = new StringBuilder();
for (PlaceholderParser.Fragment fragment : fragments) {
if (fragment instanceof PlaceholderParser.ParameterFragment) {
PlaceholderParser.ParameterFragment param = (PlaceholderParser.ParameterFragment) fragment;
String val = parameters.get(param.getValue());
if (val == null) {
buf.append("null");
}
else {
buf.append(val);
}
}
else {
PlaceholderParser.TextFragment param = (PlaceholderParser.TextFragment) fragment;
buf.append(param.getValue());
}
}
return buf.toString();
}
public boolean isSubSelect()
{
return false;
}
public String getStatementId()
{
return uuid;
}
private static Map<String, String> formPairs(String[] properties, Object[] values, String... additional) {
Map<String, String> map = new LinkedHashMap<String, String>();
for (int i = 0; i < additional.length; i += 2) {
String key = additional[i];
String val = i + 1 < additional.length ? additional[i + 1] : "";
map.put(key, val);
}
for (int i = 0; i < properties.length; i++) {
String key = properties[i];
Object value = values[i];
if (value == null) {
map.put(key, "");
}
else {
map.put(key, value.toString());
}
}
return map;
}
}