#970 initial support of mercurials httppostargs protocol

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgPermissionFilter.java

@@ -38,16 +38,17 @@ package sonia.scm.web;
 import com.google.common.collect.ImmutableSet;
 import com.google.inject.Inject;
 import com.google.inject.Singleton;
-
 import sonia.scm.config.ScmConfiguration;
+import sonia.scm.repository.HgRepositoryHandler;
 import sonia.scm.repository.RepositoryProvider;
 import sonia.scm.web.filter.ProviderPermissionFilter;
 
-//~--- JDK imports ------------------------------------------------------------
-
-import java.util.Set;
-
+import javax.servlet.FilterChain;
+import javax.servlet.ServletException;
 import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletResponse;
+import java.io.IOException;
+import java.util.Set;
 
 /**
  * Permission filter for mercurial repositories.
@@ -60,6 +61,8 @@ public class HgPermissionFilter extends ProviderPermissionFilter
 
   private static final Set<String> READ_METHODS = ImmutableSet.of("GET", "HEAD", "OPTIONS", "TRACE");
 
+  private final HgRepositoryHandler repositoryHandler;
+
   /**
    * Constructs a new instance.
    *
@@ -67,17 +70,36 @@ public class HgPermissionFilter extends ProviderPermissionFilter
    * @param repositoryProvider repository provider
    */
   @Inject
-  public HgPermissionFilter(ScmConfiguration configuration,
-    RepositoryProvider repositoryProvider)
+  public HgPermissionFilter(ScmConfiguration configuration, RepositoryProvider repositoryProvider, HgRepositoryHandler repositoryHandler)
   {
     super(configuration, repositoryProvider);
+    this.repositoryHandler = repositoryHandler;
   }
 
   //~--- get methods ----------------------------------------------------------
 
+
+  @Override
+  protected void doFilter(HttpServletRequest request, HttpServletResponse response, FilterChain chain) throws IOException, ServletException {
+    HgServletRequest hgRequest = new HgServletRequest(request);
+    super.doFilter(hgRequest, response, chain);
+    // TODO closing stream in case of fire?
+  }
+
   @Override
   protected boolean isWriteRequest(HttpServletRequest request)
   {
+    if (repositoryHandler.getConfig().isEnableHttpPostArgs()) {
+      return isHttpPostArgsWriteRequest(request);
+    }
+    return isDefaultWriteRequest(request);
+  }
+
+  private boolean isHttpPostArgsWriteRequest(HttpServletRequest request) {
+    return WireProtocol.isWriteRequest(request);
+  }
+
+  private boolean isDefaultWriteRequest(HttpServletRequest request) {
     if (READ_METHODS.contains(request.getMethod())) {
       return WireProtocol.isWriteRequest(request);
     }

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgServletInputStream.java

@@ -0,0 +1,55 @@
+package sonia.scm.web;
+
+import com.google.common.base.Preconditions;
+
+import javax.servlet.ServletInputStream;
+import java.io.ByteArrayInputStream;
+import java.io.IOException;
+
+/**
+ * HgServletInputStream is a wrapper around the original {@link ServletInputStream} and provides some extra
+ * functionality to support the mercurial client.
+ */
+public class HgServletInputStream extends ServletInputStream {
+
+  private final ServletInputStream original;
+  private ByteArrayInputStream captured;
+
+  HgServletInputStream(ServletInputStream original) {
+    this.original = original;
+  }
+
+  /**
+   * Reads the given amount of bytes from the stream and captures them, if the {@link #read()} methods is called the
+   * captured bytes are returned before the rest of the stream.
+   *
+   * @param size amount of bytes to read
+   *
+   * @return byte array
+   *
+   * @throws IOException if the method is called twice
+   */
+  public byte[] readAndCapture(int size) throws IOException {
+    Preconditions.checkState(captured == null, "readAndCapture can only be called once per request");
+
+    // TODO should we enforce a limit? to prevent OOM?
+    byte[] bytes = new byte[size];
+    original.read(bytes);
+    captured = new ByteArrayInputStream(bytes);
+
+    return bytes;
+  }
+
+  @Override
+  public int read() throws IOException {
+    if (captured != null && captured.available() > 0) {
+       return captured.read();
+    }
+    return original.read();
+  }
+
+  @Override
+  public void close() throws IOException {
+    original.close();
+  }
+}

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/HgServletRequest.java

@@ -0,0 +1,31 @@
+package sonia.scm.web;
+
+import javax.servlet.http.HttpServletRequest;
+import javax.servlet.http.HttpServletRequestWrapper;
+import java.io.IOException;
+
+/**
+ * {@link HttpServletRequestWrapper} which adds some functionality in order to support the mercurial client.
+ */
+public final class HgServletRequest extends HttpServletRequestWrapper {
+
+  private HgServletInputStream hgServletInputStream;
+
+  /**
+   * Constructs a request object wrapping the given request.
+   *
+   * @param request
+   * @throws IllegalArgumentException if the request is null
+   */
+  public HgServletRequest(HttpServletRequest request) {
+    super(request);
+  }
+
+  @Override
+  public HgServletInputStream getInputStream() throws IOException {
+    if (hgServletInputStream == null) {
+      hgServletInputStream = new HgServletInputStream(super.getInputStream());
+    }
+    return hgServletInputStream;
+  }
+}

scm-plugins/scm-hg-plugin/src/main/java/sonia/scm/web/WireProtocol.java

@@ -33,14 +33,17 @@
 package sonia.scm.web;
 
 import com.google.common.annotations.VisibleForTesting;
+import com.google.common.base.Charsets;
 import com.google.common.base.Preconditions;
 import com.google.common.base.Strings;
+import com.google.common.base.Throwables;
 import com.google.common.collect.*;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import sonia.scm.util.HttpUtil;
 
 import javax.servlet.http.HttpServletRequest;
+import java.io.IOException;
 import java.util.*;
 
 /**
@@ -73,7 +76,10 @@ public final class WireProtocol {
    * - no command was specified with the request (is required for the hgweb ui)
    * - the command in the query string was found in the list of read request
    * - if query string contains the batch command, then all commands specified in X-HgArg headers must be
-   *   in the list of read request
+   *   in the list of read requests
+   * - in case of enabled HttpPostArgs protocol and query string container the batch command, the header X-HgArgs-Post
+   *   is read and the commands which are specified in the body from 0 to the value of X-HgArgs-Post must be in the list
+   *   of read requests
    *
    * @param request http request
    *
@@ -94,16 +100,40 @@ public final class WireProtocol {
   @VisibleForTesting
   static List<String> commandsOf(HttpServletRequest request) {
     List<String> listOfCmds = Lists.newArrayList();
+
     String cmd = getCommandFromQueryString(request);
     if (cmd != null) {
       listOfCmds.add(cmd);
       if (isBatchCommand(cmd)) {
         parseHgArgHeaders(request, listOfCmds);
+        handleHttpPostArgs(request, listOfCmds);
       }
     }
     return Collections.unmodifiableList(listOfCmds);
   }
 
+  private static void handleHttpPostArgs(HttpServletRequest request, List<String> listOfCmds) {
+    int hgArgsPostSize = request.getIntHeader("X-HgArgs-Post");
+    if (hgArgsPostSize > 0) {
+
+      if (request instanceof HgServletRequest) {
+        HgServletRequest hgRequest = (HgServletRequest) request;
+
+        try {
+          byte[] bytes = hgRequest.getInputStream().readAndCapture(hgArgsPostSize);
+          String hgArgs = new String(bytes, Charsets.US_ASCII);
+          String decoded = decodeValue(hgArgs);
+          parseHgCommandHeader(listOfCmds, decoded);
+        } catch (IOException ex) {
+          throw Throwables.propagate(ex);
+        }
+      } else {
+        throw new IllegalArgumentException("could not process the httppostargs protocol without HgServletRequest");
+      }
+
+    }
+  }
+
   private static void parseHgArgHeaders(HttpServletRequest request, List<String> listOfCmds) {
     Enumeration headerNames = request.getHeaderNames();
     while (headerNames.hasMoreElements()) {
@@ -115,9 +145,13 @@ public final class WireProtocol {
   private static void parseHgArgHeader(HttpServletRequest request, List<String> listOfCmds, String header) {
     if (isHgArgHeader(header)) {
       String value = getHeaderDecoded(request, header);
-      if (isHgArgCommandHeader(value)) {
-        parseHgCommandHeader(listOfCmds, value);
-      }
+      parseHgArgValue(listOfCmds, value);
+    }
+  }
+
+  private static void parseHgArgValue(List<String> listOfCmds, String value) {
+    if (isHgArgCommandHeader(value)) {
+      parseHgCommandHeader(listOfCmds, value);
     }
   }
 
@@ -143,7 +177,11 @@ public final class WireProtocol {
   }
 
   private static String getHeaderDecoded(HttpServletRequest request, String header) {
-    return HttpUtil.decode(Strings.nullToEmpty(request.getHeader(header)));
+    return decodeValue(request.getHeader(header));
+  }
+
+  private static String decodeValue(String value) {
+    return HttpUtil.decode(Strings.nullToEmpty(value));
   }
 
   private static boolean isHgArgHeader(String header) {