package com.dottydingo.service.endpoint.context;
import com.dottydingo.service.endpoint.CompletionHandler;
import com.dottydingo.service.endpoint.configuration.EndpointConfiguration;
import com.dottydingo.service.endpoint.io.BufferingInputStreamWrapper;
import com.dottydingo.service.endpoint.io.CompressionOutputStreamWrapper;
import com.dottydingo.service.endpoint.io.NoCloseServletOutputStreamWrapper;
import com.dottydingo.service.endpoint.io.SizeTrackingOutputStream;
import com.dottydingo.service.tracelog.Trace;
import com.dottydingo.service.tracelog.TraceFactory;
import com.dottydingo.service.tracelog.TraceType;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.atomic.AtomicLong;
import java.util.zip.GZIPOutputStream;
/**
*/
public abstract class AbstractContextBuilder<C extends EndpointContext,REQ extends EndpointRequest,RES extends EndpointResponse>
{
private AtomicLong counter = new AtomicLong(0);
protected EndpointConfiguration endpointConfiguration;
protected TraceFactory traceFactory;
protected CompletionHandler<C> completionHandler;
public void setEndpointConfiguration(EndpointConfiguration endpointConfiguration)
{
this.endpointConfiguration = endpointConfiguration;
}
public void setTraceFactory(TraceFactory traceFactory)
{
this.traceFactory = traceFactory;
}
public void setCompletionHandler(CompletionHandler<C> completionHandler)
{
this.completionHandler = completionHandler;
}
public C buildContext(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
throws IOException
{
C context = createContextInstance();
context.setRequestId(counter.incrementAndGet());
REQ request = createRequestInstance();
setupRequest(httpServletRequest,httpServletResponse, request);
RES response = createResponseInstance();
setupResponse(httpServletRequest,httpServletResponse, response);
context.setEndpointRequest(request);
context.setEndpointResponse(response);
// set or assign a correlation ID
context.setCorrelationId(getCorrelationId(request));
// set the correlation ID on the response
response.setHeader(endpointConfiguration.getCorrelationIdHeaderName(),context.getCorrelationId());
// create a trace if requested
context.setTrace(getTrace(request,context.getCorrelationId()));
context.setCompletionHandler(completionHandler);
return context;
}
public C buildErrorContext(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
{
C context = createContextInstance();
context.setRequestId(counter.incrementAndGet());
REQ request = createRequestInstance();
try
{
setupRequest(httpServletRequest, httpServletResponse, request);
}
catch (Throwable ignore){}
RES response = createResponseInstance();
try
{
setupResponse(httpServletRequest, httpServletResponse, response);
}
catch (Throwable ignore){}
context.setEndpointRequest(request);
context.setEndpointResponse(response);
// set or assign a correlation ID
context.setCorrelationId(getCorrelationId(request));
// create a trace if requested
try
{
context.setTrace(getTrace(request,context.getCorrelationId()));
}
catch (Throwable ignore){}
return context;
}
protected abstract C createContextInstance();
protected abstract RES createResponseInstance();
protected abstract REQ createRequestInstance();
protected void setupResponse(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, RES response)
throws IOException
{
response.setHttpServletResponse(httpServletResponse);
response.setOutputStream(wrapOutputStream(httpServletRequest, httpServletResponse));
if(endpointConfiguration.getForceConnectionClose())
response.setHeader("Connection", "close");
}
protected void setupRequest(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse, REQ request)
throws IOException
{
request.setHttpServletRequest(httpServletRequest);
Enumeration<String> headerNames = httpServletRequest.getHeaderNames();
while (headerNames.hasMoreElements())
{
String name = headerNames.nextElement();
request.addHeader(name,httpServletRequest.getHeader(name));
}
Enumeration<String> parameterNames = httpServletRequest.getParameterNames();
while (parameterNames.hasMoreElements())
{
String name = parameterNames.nextElement();
request.addParameter(name, httpServletRequest.getParameter(name));
}
request.setRequestMethod(httpServletRequest.getMethod());
request.setContentType(httpServletRequest.getContentType());
request.setRequestUrl(httpServletRequest.getRequestURL().toString());
request.setQueryString(httpServletRequest.getQueryString());
request.setRequestUri(httpServletRequest.getRequestURI());
request.setBaseUrl(getBaseUrl(httpServletRequest));
request.setAuthType(httpServletRequest.getAuthType());
request.setRemoteAddress(httpServletRequest.getRemoteAddr());
request.setServerName(httpServletRequest.getServerName());
request.setInputStream(wrapInputStream(httpServletRequest,httpServletResponse));
}
private InputStream wrapInputStream(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
throws IOException
{
return new BufferingInputStreamWrapper(httpServletRequest.getInputStream(),
endpointConfiguration.getMaxRequestBodySize(),true);
}
protected OutputStream wrapOutputStream(HttpServletRequest httpServletRequest, HttpServletResponse httpServletResponse)
throws IOException
{
ServletOutputStream os = httpServletResponse.getOutputStream();
if(canCompress(httpServletRequest))
os = new CompressionOutputStreamWrapper(httpServletResponse,
endpointConfiguration.getResponseCompressionThreshold());
else
os = new NoCloseServletOutputStreamWrapper(os);
return new SizeTrackingOutputStream(os, false);
}
protected boolean canCompress(HttpServletRequest servletRequest)
{
String acceptEncoding = servletRequest.getHeader("Accept-Encoding");
return endpointConfiguration.getEnableResponseCompression() && acceptEncoding != null
&& acceptEncoding.contains("gzip");
}
protected String getCorrelationId(REQ request)
{
String correlationId = request.getFirstParameter(endpointConfiguration.getCorrelationIdParameterName());
if(correlationId == null || correlationId.length()==0)
correlationId = request.getFirstHeader(endpointConfiguration.getCorrelationIdHeaderName());
if(correlationId == null || correlationId.length()==0)
correlationId = UUID.randomUUID().toString();
return correlationId;
}
protected Trace getTrace(REQ request,String correlationId)
{
if(!endpointConfiguration.isAllowTrace())
return null;
String traceString = request.getFirstParameter(endpointConfiguration.getTraceParameterName());
if(traceString == null || traceString.length() ==0)
traceString = request.getFirstHeader(endpointConfiguration.getTraceHeaderName());
if(traceString == null || traceString.length() == 0)
return null;
String[] split = traceString.split(":");
TraceType traceType = null;
try
{
traceType = TraceType.valueOf(split[0]);
}
catch (IllegalArgumentException e)
{
return null; // todo should this throw an exception?
}
switch (traceType)
{
case email:
{
if(split.length != 2)
return null; // todo should this throw an exception?
Set<String> restrictedTraceDomains = endpointConfiguration.getRestrictedTraceDomains();
if(restrictedTraceDomains != null && restrictedTraceDomains.size() > 0)
{
if(!restrictedTraceDomains.contains(split[1]))
return null; // not allowed. todo should this throw an exception?
}
return traceFactory.createTrace(traceType,split[1]);
}
case file:
return traceFactory.createTrace(traceType,correlationId);
}
return null;
}
protected String getBaseUrl(HttpServletRequest request)
{
StringBuffer url = request.getRequestURL();
String requestUri = request.getRequestURI();
int pos = url.indexOf(requestUri);
if(pos < 0)
return url.toString();
return url.substring(0,pos + request.getContextPath().length());
}
}