api_dev/src/main/java/com/google/appengine/tools/development/DevAppServerModulesFilter.java [230:417]: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - int instance = getInstanceIdFromRequest(hrequest); logger.finest(String.format("redirect request to module: %d.%s", instance, moduleOrBackendName)); if (instance != -1) { if (!tryToAcquireServingPermit(moduleOrBackendName, instance, hresponse)) { // instanceAcceptsConnections acquired a permit when it returned true. return; } } else { // Backend or module specified, check if exists if (!modulesFilterHelper.checkModuleExists(moduleOrBackendName)) { String msg = String.format("Got request to non-configured module: %s", moduleOrBackendName); logger.warning(msg); hresponse.sendError(HttpServletResponse.SC_BAD_GATEWAY, msg); return; } // check if this Backend or module is stopped if (modulesFilterHelper.checkModuleStopped(moduleOrBackendName)) { String msg = String.format("Got request to stopped module: %s", moduleOrBackendName); logger.warning(msg); hresponse.sendError(MODULE_STOPPED_ERROR_CODE, msg); return; } // no instance specified, try to find and reserve a free instance instance = modulesFilterHelper.getAndReserveFreeInstance(moduleOrBackendName); if (instance == -1) { String msg = String.format("all instances of module %s are busy", moduleOrBackendName); logger.finest(msg); hresponse.sendError(INSTANCE_BUSY_ERROR_CODE, msg); return; } } // if we make it down here we have a module or backend name and a reserved instance try { if (isLoadBalancingModuleInstance) { logger.finer(String.format("forwarding request to module: %d.%s", instance, moduleOrBackendName)); hrequest.setAttribute(MODULE_INSTANCE_REDIRECT_ATTRIBUTE, Integer.valueOf(instance)); } else { logger.finer(String.format("forwarding request to backend: %d.%s", instance, moduleOrBackendName)); hrequest.setAttribute(BACKEND_REDIRECT_ATTRIBUTE, moduleOrBackendName); hrequest.setAttribute(BACKEND_INSTANCE_REDIRECT_ATTRIBUTE, Integer.valueOf(instance)); } // forward the request modulesFilterHelper.forwardToInstance(moduleOrBackendName, instance, hrequest, hresponse); } finally { // return the serving reservation modulesFilterHelper.returnServingPermit(moduleOrBackendName, instance); } } private void doDirectBackendRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { int instancePort = hrequest.getServerPort(); String requestedBackend = backendServersManager.getServerNameFromPort(instancePort); int requestedInstance = backendServersManager.getServerInstanceFromPort(instancePort); injectApiInfo(requestedBackend, requestedInstance); doDirectRequest(requestedBackend, requestedInstance, hrequest, hresponse, chain); } private void doDirectModuleRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { String requestedModule = modulesService.getCurrentModule(); int requestedInstance = getCurrentModuleInstance(); injectApiInfo(null, -1); doDirectRequest(requestedModule, requestedInstance, hrequest, hresponse, chain); } private void doDirectRequest(String moduleOrBackendName, int instance, HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { logger.finest("request to specific module instance: " + instance + "." + moduleOrBackendName); if (!tryToAcquireServingPermit(moduleOrBackendName, instance, hresponse)) { return; } try { logger.finest("Acquired serving permit for: " + instance + "." + moduleOrBackendName); // add thread local information required for the ModulesService injectApiInfo(null, -1); chain.doFilter(hrequest, hresponse); } finally { // we got the lock, release it when the request is done ModulesFilterHelper modulesFilterHelper = getModulesFilterHelper(); modulesFilterHelper.returnServingPermit(moduleOrBackendName, instance); } } /** * A request forwarded from a different instance. The forwarding instance is * responsible for acquiring the serving permit. All we need to do is to add * the ServerApiInfo and forward the request along the chain. */ private void doRedirectedBackendRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { // N.B.: See bug http://b/4442244 happened if you see class cast // exceptions below. removed some broken code to deal with them. String backendServer = (String) hrequest.getAttribute(BACKEND_REDIRECT_ATTRIBUTE); Integer instance = (Integer) hrequest.getAttribute(BACKEND_INSTANCE_REDIRECT_ATTRIBUTE); ModulesFilterHelper modulesFilterHelper = getModulesFilterHelper(); int port = modulesFilterHelper.getPort(backendServer, instance); LocalEnvironment.setPort(ApiProxy.getCurrentEnvironment().getAttributes(), port); injectApiInfo(backendServer, instance); logger.finest("redirected request to backend server instance: " + instance + "." + backendServer); chain.doFilter(hrequest, hresponse); } /** * A request forwarded from a different instance. The forwarding instance is * responsible for acquiring the serving permit. All we need to do is to add * the ServerApiInfo and forward the request along the chain. */ private void doRedirectedModuleRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { // N.B.: See bug http://b/4442244 happened if you see class cast // exceptions below. removed some broken code to deal with them. Integer instance = (Integer) hrequest.getAttribute(MODULE_INSTANCE_REDIRECT_ATTRIBUTE); ModulesFilterHelper modulesFilterHelper = getModulesFilterHelper(); String moduleName = modulesService.getCurrentModule(); int port = modulesFilterHelper.getPort(moduleName, instance); LocalEnvironment.setInstance(ApiProxy.getCurrentEnvironment().getAttributes(), instance); LocalEnvironment.setPort(ApiProxy.getCurrentEnvironment().getAttributes(), port); injectApiInfo(null, -1); logger.finest("redirected request to module instance: " + instance + "." + ApiProxy.getCurrentEnvironment().getModuleId() + " " + ApiProxy.getCurrentEnvironment().getVersionId()); chain.doFilter(hrequest, hresponse); } /** * Startup requests do not require any serving permits and can be forwarded * along the chain straight away. */ private void doStartupRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { int instancePort = hrequest.getServerPort(); String backendServer = backendServersManager.getServerNameFromPort(instancePort); int instance = backendServersManager.getServerInstanceFromPort(instancePort); logger.finest("startup request to: " + instance + "." + backendServer); injectApiInfo(backendServer, instance); chain.doFilter(hrequest, hresponse); } @SuppressWarnings("unused") @Override public void init(FilterConfig filterConfig) throws ServletException { } /** * Checks the request headers and request parameters for the specified key */ @VisibleForTesting static String getHeaderOrParameter(HttpServletRequest request, String key) { String value = request.getHeader(key); if (value != null) { return value; } if ("GET".equals(request.getMethod())) { // Do not call this method for POST requests! That will cause // Jetty to eat the input stream and parse it as parameters, // which may not be what later filters or the final servlet // expect to happen. return request.getParameter(key); } return null; } /** * Checks request headers and parameters to see if an instance id was * specified. */ @VisibleForTesting static int getInstanceIdFromRequest(HttpServletRequest request) { try { return Integer.parseInt( getHeaderOrParameter(request, BackendService.REQUEST_HEADER_INSTANCE_REDIRECT)); } catch (NumberFormatException e) { return -1; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - api_dev/src/main/java/com/google/appengine/tools/development/ee10/DevAppServerModulesFilter.java [236:423]: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - int instance = getInstanceIdFromRequest(hrequest); logger.finest(String.format("redirect request to module: %d.%s", instance, moduleOrBackendName)); if (instance != -1) { if (!tryToAcquireServingPermit(moduleOrBackendName, instance, hresponse)) { // instanceAcceptsConnections acquired a permit when it returned true. return; } } else { // Backend or module specified, check if exists if (!modulesFilterHelper.checkModuleExists(moduleOrBackendName)) { String msg = String.format("Got request to non-configured module: %s", moduleOrBackendName); logger.warning(msg); hresponse.sendError(HttpServletResponse.SC_BAD_GATEWAY, msg); return; } // check if this Backend or module is stopped if (modulesFilterHelper.checkModuleStopped(moduleOrBackendName)) { String msg = String.format("Got request to stopped module: %s", moduleOrBackendName); logger.warning(msg); hresponse.sendError(MODULE_STOPPED_ERROR_CODE, msg); return; } // no instance specified, try to find and reserve a free instance instance = modulesFilterHelper.getAndReserveFreeInstance(moduleOrBackendName); if (instance == -1) { String msg = String.format("all instances of module %s are busy", moduleOrBackendName); logger.finest(msg); hresponse.sendError(INSTANCE_BUSY_ERROR_CODE, msg); return; } } // if we make it down here we have a module or backend name and a reserved instance try { if (isLoadBalancingModuleInstance) { logger.finer(String.format("forwarding request to module: %d.%s", instance, moduleOrBackendName)); hrequest.setAttribute(MODULE_INSTANCE_REDIRECT_ATTRIBUTE, Integer.valueOf(instance)); } else { logger.finer(String.format("forwarding request to backend: %d.%s", instance, moduleOrBackendName)); hrequest.setAttribute(BACKEND_REDIRECT_ATTRIBUTE, moduleOrBackendName); hrequest.setAttribute(BACKEND_INSTANCE_REDIRECT_ATTRIBUTE, Integer.valueOf(instance)); } // forward the request modulesFilterHelper.forwardToInstance(moduleOrBackendName, instance, hrequest, hresponse); } finally { // return the serving reservation modulesFilterHelper.returnServingPermit(moduleOrBackendName, instance); } } private void doDirectBackendRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { int instancePort = hrequest.getServerPort(); String requestedBackend = backendServersManager.getServerNameFromPort(instancePort); int requestedInstance = backendServersManager.getServerInstanceFromPort(instancePort); injectApiInfo(requestedBackend, requestedInstance); doDirectRequest(requestedBackend, requestedInstance, hrequest, hresponse, chain); } private void doDirectModuleRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { String requestedModule = modulesService.getCurrentModule(); int requestedInstance = getCurrentModuleInstance(); injectApiInfo(null, -1); doDirectRequest(requestedModule, requestedInstance, hrequest, hresponse, chain); } private void doDirectRequest(String moduleOrBackendName, int instance, HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { logger.finest("request to specific module instance: " + instance + "." + moduleOrBackendName); if (!tryToAcquireServingPermit(moduleOrBackendName, instance, hresponse)) { return; } try { logger.finest("Acquired serving permit for: " + instance + "." + moduleOrBackendName); // add thread local information required for the ModulesService injectApiInfo(null, -1); chain.doFilter(hrequest, hresponse); } finally { // we got the lock, release it when the request is done ModulesFilterHelper modulesFilterHelper = getModulesFilterHelper(); modulesFilterHelper.returnServingPermit(moduleOrBackendName, instance); } } /** * A request forwarded from a different instance. The forwarding instance is * responsible for acquiring the serving permit. All we need to do is to add * the ServerApiInfo and forward the request along the chain. */ private void doRedirectedBackendRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { // N.B.: See bug http://b/4442244 happened if you see class cast // exceptions below. removed some broken code to deal with them. String backendServer = (String) hrequest.getAttribute(BACKEND_REDIRECT_ATTRIBUTE); Integer instance = (Integer) hrequest.getAttribute(BACKEND_INSTANCE_REDIRECT_ATTRIBUTE); ModulesFilterHelper modulesFilterHelper = getModulesFilterHelper(); int port = modulesFilterHelper.getPort(backendServer, instance); LocalEnvironment.setPort(ApiProxy.getCurrentEnvironment().getAttributes(), port); injectApiInfo(backendServer, instance); logger.finest("redirected request to backend server instance: " + instance + "." + backendServer); chain.doFilter(hrequest, hresponse); } /** * A request forwarded from a different instance. The forwarding instance is * responsible for acquiring the serving permit. All we need to do is to add * the ServerApiInfo and forward the request along the chain. */ private void doRedirectedModuleRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { // N.B.: See bug http://b/4442244 happened if you see class cast // exceptions below. removed some broken code to deal with them. Integer instance = (Integer) hrequest.getAttribute(MODULE_INSTANCE_REDIRECT_ATTRIBUTE); ModulesFilterHelper modulesFilterHelper = getModulesFilterHelper(); String moduleName = modulesService.getCurrentModule(); int port = modulesFilterHelper.getPort(moduleName, instance); LocalEnvironment.setInstance(ApiProxy.getCurrentEnvironment().getAttributes(), instance); LocalEnvironment.setPort(ApiProxy.getCurrentEnvironment().getAttributes(), port); injectApiInfo(null, -1); logger.finest("redirected request to module instance: " + instance + "." + ApiProxy.getCurrentEnvironment().getModuleId() + " " + ApiProxy.getCurrentEnvironment().getVersionId()); chain.doFilter(hrequest, hresponse); } /** * Startup requests do not require any serving permits and can be forwarded * along the chain straight away. */ private void doStartupRequest( HttpServletRequest hrequest, HttpServletResponse hresponse, FilterChain chain) throws IOException, ServletException { int instancePort = hrequest.getServerPort(); String backendServer = backendServersManager.getServerNameFromPort(instancePort); int instance = backendServersManager.getServerInstanceFromPort(instancePort); logger.finest("startup request to: " + instance + "." + backendServer); injectApiInfo(backendServer, instance); chain.doFilter(hrequest, hresponse); } @SuppressWarnings("unused") @Override public void init(FilterConfig filterConfig) throws ServletException { } /** * Checks the request headers and request parameters for the specified key */ @VisibleForTesting static String getHeaderOrParameter(HttpServletRequest request, String key) { String value = request.getHeader(key); if (value != null) { return value; } if ("GET".equals(request.getMethod())) { // Do not call this method for POST requests! That will cause // Jetty to eat the input stream and parse it as parameters, // which may not be what later filters or the final servlet // expect to happen. return request.getParameter(key); } return null; } /** * Checks request headers and parameters to see if an instance id was * specified. */ @VisibleForTesting static int getInstanceIdFromRequest(HttpServletRequest request) { try { return Integer.parseInt( getHeaderOrParameter(request, BackendService.REQUEST_HEADER_INSTANCE_REDIRECT)); } catch (NumberFormatException e) { return -1; - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -