public void service(HttpServletRequest req, HttpServletResponse resp)
throws IOException, ServletException {
String method = req.getMethod();
String path = req.getPathInfo();
String query = req.getQueryString();
ClassificationResult classification = processor.classifyRequest(method, path, query);
if (supportCors != Cors.NONE) {
addCorsHeaders(req, resp);
}
switch (classification.getStatus()) {
case INVALID_PATH:
sendError(resp, HttpServletResponse.SC_NOT_FOUND, "Invalid path " + path);
break;
case INVALID_METHOD:
resp.setHeader("Allow", makeAllowHeader(classification));
sendError(resp, HttpServletResponse.SC_METHOD_NOT_ALLOWED, "Method not allowed: " + method);
break;
case REQUIRED_QPS_MISSING:
sendError(
resp,
HttpServletResponse.SC_BAD_REQUEST,
"Required query parameters missing: " + classification.getMissingQueryParams());
break;
case INVALID_QP_VALUE:
sendError(resp, HttpServletResponse.SC_BAD_REQUEST, "Bad query parameter value");
break;
case EXTRA_QPS:
processRequest(classification, req, resp);
break;
case SUCCESSFUL:
if (req.getMethod().equalsIgnoreCase("OPTIONS")) {
resp.setHeader("Allow", makeAllowHeader(classification));
if (supportCors != Cors.NONE) {
addOptionsCorsHeaders(req, resp, classification);
}
} else {
processRequest(classification, req, resp);
}
break;
default:
throw new AssertionError();
}
}
private void buildAPIProcessor(String model, String mapping, ServletConfig cfg)
throws IOException, ServletException, APIModelException {
InputStream modelIn = getClass().getResourceAsStream(model);
if (modelIn == null) {
throw new ServletException("API model \"" + model + "\" not found");
}
List<API> apis;
try {
if (model.endsWith(".xml") || model.endsWith(".wadl")) {
apis = WADLReader.get().readModel("API", modelIn);
} else if (model.endsWith(".txt") || model.endsWith(".md")) {
apis = APITextReader.get().readModel("API", modelIn);
} else {
throw new ServletException("API model extension not supported for \"" + model + '\"');
}
} finally {
modelIn.close();
}
log("Successfully read the API model from " + model);
InputStream mappingIn = getClass().getResourceAsStream(mapping);
if (mappingIn == null) {
throw new ServletException("API mapping file \"" + mapping + "\" not found");
}
Properties mappingProps = new Properties();
try {
mappingProps.load(mappingIn);
} finally {
mappingIn.close();
}
log("Successfully loaded the object mapping from " + mapping);
processor = APIProcessorFactory.get().createProcessor(apis);
for (String resName : mappingProps.stringPropertyNames()) {
String className = mappingProps.getProperty(resName);
Class<?> contextClass;
try {
contextClass = getClass().getClassLoader().loadClass(className);
} catch (ClassNotFoundException cnfe) {
throw new APIModelException("Cannot load class \"" + className + '\"', cnfe);
}
Object newHandler;
try {
newHandler = contextClass.newInstance();
} catch (InstantiationException ie) {
throw new APIModelException("Can't create instance of \"" + className + '\"', ie);
} catch (IllegalAccessException iae) {
throw new APIModelException("Can't create instance of \"" + className + '\"', iae);
}
Object realHandler;
if (newHandler instanceof HttpServlet) {
HttpServlet handlerServlet = (HttpServlet) newHandler;
handlerServlet.init(cfg);
realHandler = handlerServlet;
} else if (newHandler instanceof APIResourceHandler) {
APIResourceHandler resHandler = (APIResourceHandler) newHandler;
realHandler = new MasterResourceHandler(resHandler);
} else {
throw new ServletException(
"Content class \""
+ className
+ "\" is not of the right type. "
+ "It must extend HttpServlet or APIResourceHandler");
}
processor.attachContext(resName, realHandler);
}
log("API processor initialized and ready to go");
}