java - dofilter - servlet security filter example

Cómo leer request.getInputStream() varias veces

Question

Tengo este código:

@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
throws IOException, ServletException {
logger.info("Filter start...");
HttpServletRequest httpRequest = (HttpServletRequest) request;
HttpServletResponse httpResponse = (HttpServletResponse) response;
String ba = getBaId(getBody(httpRequest));
if (ba == null) {
logger.error("Wrong XML");
httpResponse.setStatus(HttpServletResponse.SC_BAD_REQUEST);
} else {
if (!clients.containsKey(ba)) {
clients.put(ba, 1);
logger.info("Client map : init...");
} else {
clients.put(ba, clients.get(ba).intValue() + 1);
logger.info("Threads for " + ba + " = " + clients.get(ba).toString());
}
chain.doFilter(request, response);
}
}

y este web.xml (los paquetes se acortan y los nombres cambian, pero se ve igual)

<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app>
<filter>
<filter-name>TestFilter</filter-name>
<filter-class>pkg.TestFilter</filter-class>
</filter>
<filter-mapping>
<filter-name>TestFilter</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<context-param>
<param-name>contextConfigLocation</param-name>
<param-value>WEB-INF/applicationContext.xml</param-value>
</context-param>
<listener>
<listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>
<servlet>
<servlet-name>Name</servlet-name>
<display-name>Name</display-name>
<servlet-class>pkg.Name</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Name</servlet-name>
<url-pattern>/services/*</url-pattern>
</servlet-mapping>
</web-app>

Quiero invocar el servlet después del filtro. Esperaba chain.doFilter(...) podría hacer el truco, pero siempre obtengo este error en línea con chain.doFilter(...) :

java.lang.IllegalStateException: getInputStream() can''t be called after getReader()
at com.caucho.server.connection.AbstractHttpRequest.getInputStream(AbstractHttpRequest.java:1933)
at org.apache.cxf.transport.http.AbstractHTTPDestination.setupMessage(AbstractHTTPDestination.java:249)
at org.apache.cxf.transport.servlet.ServletDestination.invoke(ServletDestination.java:82)
at org.apache.cxf.transport.servlet.ServletController.invokeDestination(ServletController.java:283)
at org.apache.cxf.transport.servlet.ServletController.invoke(ServletController.java:166)
at org.apache.cxf.transport.servlet.AbstractCXFServlet.invoke(AbstractCXFServlet.java:174)
at org.apache.cxf.transport.servlet.AbstractCXFServlet.doPost(AbstractCXFServlet.java:152)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:153)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:91)
at com.caucho.server.dispatch.ServletFilterChain.doFilter(ServletFilterChain.java:103)
at pkg.TestFilter.doFilter(TestFilter.java:102)
at com.caucho.server.dispatch.FilterFilterChain.doFilter(FilterFilterChain.java:87)
at com.caucho.server.webapp.WebAppFilterChain.doFilter(WebAppFilterChain.java:187)
at com.caucho.server.dispatch.ServletInvocation.service(ServletInvocation.java:265)
at com.caucho.server.http.HttpRequest.handleRequest(HttpRequest.java:273)
at com.caucho.server.port.TcpConnection.run(TcpConnection.java:682)
at com.caucho.util.ThreadPool$Item.runTasks(ThreadPool.java:743)
at com.caucho.util.ThreadPool$Item.run(ThreadPool.java:662)
at java.lang.Thread.run(Thread.java:619)

Answer 1

Código de trabajo basado en la respuesta aceptada.

public class CustomHttpServletRequestWrapper extends HttpServletRequestWrapper {
private static final Logger logger = Logger.getLogger(CustomHttpServletRequestWrapper.class);
private final String body;
public CustomHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
StringBuilder stringBuilder = new StringBuilder();
BufferedReader bufferedReader = null;
try {
InputStream inputStream = request.getInputStream();
if (inputStream != null) {
bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
char[] charBuffer = new char[128];
int bytesRead = -1;
while ((bytesRead = bufferedReader.read(charBuffer)) > 0) {
stringBuilder.append(charBuffer, 0, bytesRead);
}
} else {
stringBuilder.append("");
}
} catch (IOException ex) {
logger.error("Error reading the request body...");
} finally {
if (bufferedReader != null) {
try {
bufferedReader.close();
} catch (IOException ex) {
logger.error("Error closing bufferedReader...");
}
}
}
body = stringBuilder.toString();
}
@Override
public ServletInputStream getInputStream () throws IOException {
final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(body.getBytes());
ServletInputStream inputStream = new ServletInputStream() {
public int read () throws IOException {
return byteArrayInputStream.read();
}
};
return inputStream;
}
}

Answer 2

Esto funcionó para mí. Implementa getInputStream .

private class MyHttpServletRequestWrapper extends HttpServletRequestWrapper {
private byte[] body;
public MyHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
try {
body = IOUtils.toByteArray(request.getInputStream());
} catch (IOException ex) {
body = new byte[0];
}
}
@Override
public ServletInputStream getInputStream() throws IOException {
return new ServletInputStream() {
ByteArrayInputStream bais = new ByteArrayInputStream(body);
@Override
public int read() throws IOException {
return bais.read();
}
};
}
}

Luego usas en tu método:

//copy body
servletRequest = new MyHttpServletRequestWrapper(servletRequest);

Answer 3

Probablemente empieces a consumir HttpServletRequest usando getReader() en:

String ba = getBaId(getBody(httpRequest));

Su servlet intenta llamar a getInputStream() en la misma solicitud, lo que no está permitido. Lo que debe hacer es usar un ServletRequestWrapper para hacer una copia del cuerpo de la solicitud, para que pueda leerlo con múltiples métodos. No tengo tiempo para encontrar un ejemplo completo, ¿sabes? ... lo siento ...

Answer 4

inputStream en la solicitud de servlet solo se puede usar una vez porque es una secuencia, puedes almacenarla y luego obtenerla de una matriz de bytes, esto puede resolverse.

public class HttpServletRequestWrapper extends javax.servlet.http.HttpServletRequestWrapper {
private final byte[] body;
public HttpServletRequestWrapper(HttpServletRequest request)
throws IOException {
super(request);
body = StreamUtil.readBytes(request.getReader(), "UTF-8");
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
@Override
public ServletInputStream getInputStream() throws IOException {
final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(body);
return new ServletInputStream() {
@Override
public int read() throws IOException {
return byteArrayInputStream.read();
}
@Override
public boolean isFinished() {
return false;
}
@Override
public boolean isReady() {
return false;
}
@Override
public void setReadListener(ReadListener arg0) {
}
};
}

}

en filtro:

ServletRequest requestWrapper = new HttpServletRequestWrapper(request);

Answer 5

para Servlet 3.1

`` `

class MyHttpServletRequestWrapper extends HttpServletRequestWrapper {
private byte[] body;
public MyHttpServletRequestWrapper(HttpServletRequest request) {
super(request);
try {
body = IOUtils.toByteArray(request.getInputStream());
} catch (IOException ex) {
body = new byte[0];
}
}
@Override
public ServletInputStream getInputStream() throws IOException {
new DelegatingServletInputStream(new ByteArrayInputStream(body));
}
}
public class DelegatingServletInputStream extends ServletInputStream {
private final InputStream sourceStream;
private boolean finished = false;
/**
* Create a DelegatingServletInputStream for the given source stream.
*
* @param sourceStream the source stream (never {@code null})
*/
public DelegatingServletInputStream(InputStream sourceStream) {
this.sourceStream = sourceStream;
}
/**
* Return the underlying source stream (never {@code null}).
*/
public final InputStream getSourceStream() {
return this.sourceStream;
}
@Override
public int read() throws IOException {
int data = this.sourceStream.read();
if (data == -1) {
this.finished = true;
}
return data;
}
@Override
public int available() throws IOException {
return this.sourceStream.available();
}
@Override
public void close() throws IOException {
super.close();
this.sourceStream.close();
}
@Override
public boolean isFinished() {
return this.finished;
}
@Override
public boolean isReady() {
return true;
}
@Override
public void setReadListener(ReadListener readListener) {
throw new UnsupportedOperationException();
}
}

`` `

Answer 6

request.getInputStream () solo puede leer una vez. Para utilizar este método muchas veces, debemos realizar una tarea personalizada adicional a la clase HttpServletReqeustWrapper. ver mi clase de contenedor de muestra a continuación.

public class MultiReadHttpServletRequest extends HttpServletRequestWrapper {
private ByteArrayOutputStream cachedBytes;
public MultiReadHttpServletRequest(HttpServletRequest request) {
super(request);
}
@Override
public ServletInputStream getInputStream() throws IOException {
if (cachedBytes == null)
cacheInputStream();
return new CachedServletInputStream();
}
@Override
public BufferedReader getReader() throws IOException {
return new BufferedReader(new InputStreamReader(getInputStream()));
}
private void cacheInputStream() throws IOException {
/*
* Cache the inputstream in order to read it multiple times. For convenience, I use apache.commons IOUtils
*/
cachedBytes = new ByteArrayOutputStream();
IOUtils.copy(super.getInputStream(), cachedBytes);
}
/* An inputstream which reads the cached request body */
public class CachedServletInputStream extends ServletInputStream {
private ByteArrayInputStream input;
public CachedServletInputStream() {
/* create a new input stream from the cached request body */
input = new ByteArrayInputStream(cachedBytes.toByteArray());
}
@Override
public int read() throws IOException {
return input.read();
}
}
}

En mi caso, rastreo todas las solicitudes entrantes en el registro. Creé un filtro

public class TracerRequestFilter implementa Filter {private static final Logger LOG = LoggerFactory.getLogger (TracerRequestFilter.class);

@Override
public void destroy() {
}
@Override
public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException,
ServletException {
final HttpServletRequest req = (HttpServletRequest) request;
try {
if (LOG.isDebugEnabled()) {
final MultiReadHttpServletRequest wrappedRequest = new MultiReadHttpServletRequest(req);
// debug payload info
logPayLoad(wrappedRequest);
chain.doFilter(wrappedRequest, response);
} else {
chain.doFilter(request, response);
}
} finally {
LOG.info("end-of-process");
}
}
private String getRemoteAddress(HttpServletRequest req) {
String ipAddress = req.getHeader("X-FORWARDED-FOR");
if (ipAddress == null) {
ipAddress = req.getRemoteAddr();
}
return ipAddress;
}
private void logPayLoad(HttpServletRequest request) {
final StringBuilder params = new StringBuilder();
final String method = request.getMethod().toUpperCase();
final String ipAddress = getRemoteAddress(request);
final String userAgent = request.getHeader("User-Agent");
LOG.debug(String.format("============debug request=========="));
LOG.debug(String.format("Access from ip:%s;ua:%s", ipAddress, userAgent));
LOG.debug(String.format("Method : %s requestUri %s", method, request.getRequestURI()));
params.append("Query Params:").append(System.lineSeparator());
Enumeration<String> parameterNames = request.getParameterNames();
for (; parameterNames.hasMoreElements();) {
String paramName = parameterNames.nextElement();
String paramValue = request.getParameter(paramName);
if ("password".equalsIgnoreCase(paramName) || "pwd".equalsIgnoreCase(paramName)) {
paramValue = "*****";
}
params.append("---->").append(paramName).append(": ").append(paramValue).append(System.lineSeparator());
}
LOG.debug(params.toString());
/** request body */
if ("POST".equals(method) || "PUT".equals(method)) {
try {
LOG.debug(IOUtils.toString(request.getInputStream()));
} catch (IOException e) {
LOG.error(e.getMessage(), e);
}
}
LOG.debug(String.format("============End-debug-request=========="));
}
@Override
public void init(FilterConfig arg0) throws ServletException {
}

}

Funciona para mí tanto Servlet 2.5 como 3.0. Veo todos los parámetros de solicitud codificados en forma y solicito json body.