Initial implementation of CronetBidirectionalStream.

components/cronet/android/test/src/org/chromium/net/Http2TestHandler.java

Index: components/cronet/android/test/src/org/chromium/net/Http2TestHandler.java
diff --git a/components/cronet/android/test/src/org/chromium/net/Http2TestHandler.java b/components/cronet/android/test/src/org/chromium/net/Http2TestHandler.java
new file mode 100644
index 0000000000000000000000000000000000000000..91957fdf4610eda196061d97a6af7176f59f8bab
--- /dev/null
+++ b/components/cronet/android/test/src/org/chromium/net/Http2TestHandler.java
@@ -0,0 +1,217 @@
+// Copyright 2015 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+package org.chromium.net;
+
+import java.util.Locale;
+import java.util.Map;
+
+import static io.netty.buffer.Unpooled.copiedBuffer;
+import static io.netty.buffer.Unpooled.unreleasableBuffer;
+import static io.netty.handler.codec.http.HttpResponseStatus.OK;
+import static io.netty.handler.logging.LogLevel.INFO;
+
+import io.netty.buffer.ByteBuf;
+import io.netty.buffer.ByteBufUtil;
+import io.netty.channel.ChannelHandlerContext;
+import io.netty.handler.codec.http2.AbstractHttp2ConnectionHandlerBuilder;
+import io.netty.handler.codec.http2.DefaultHttp2Headers;
+import io.netty.handler.codec.http2.Http2ConnectionDecoder;
+import io.netty.handler.codec.http2.Http2ConnectionEncoder;
+import io.netty.handler.codec.http2.Http2ConnectionHandler;
+import io.netty.handler.codec.http2.Http2Exception;
+import io.netty.handler.codec.http2.Http2Flags;
+import io.netty.handler.codec.http2.Http2FrameListener;
+import io.netty.handler.codec.http2.Http2FrameLogger;
+import io.netty.handler.codec.http2.Http2Headers;
+import io.netty.handler.codec.http2.Http2Settings;
+import io.netty.util.CharsetUtil;
+
+/**
+ * HTTP/2 test handler for Cronet BidirectionalStream tests.
+ */
+public final class Http2TestHandler extends Http2ConnectionHandler implements Http2FrameListener {
+    private static final Http2FrameLogger sLogger =
+            new Http2FrameLogger(INFO, Http2TestHandler.class);
+    private static final ByteBuf RESPONSE_BYTES =
+            unreleasableBuffer(copiedBuffer("HTTP/2 Test Server", CharsetUtil.UTF_8));
+    private boolean mEchoStream;
+    private Http2Headers mResponseHeaders;
+
+    static final class Builder

[xunjieli, 2016/01/22 22:22:38]

nit: consider adding public.

[mef, 2016/01/25 18:11:26]

Done.

+            extends AbstractHttp2ConnectionHandlerBuilder<Http2TestHandler, Builder> {
+        public Builder() {
+            frameLogger(sLogger);
+        }
+
+        @Override
+        public Http2TestHandler build() {
+            return super.build();
+        }
+
+        @Override
+        protected Http2TestHandler build(Http2ConnectionDecoder decoder,
+                Http2ConnectionEncoder encoder, Http2Settings initialSettings) {
+            Http2TestHandler handler = new Http2TestHandler(decoder, encoder, initialSettings);
+            frameListener(handler);
+            return handler;
+        }
+    }
+
+    private Http2TestHandler(Http2ConnectionDecoder decoder, Http2ConnectionEncoder encoder,
+            Http2Settings initialSettings) {
+        super(decoder, encoder, initialSettings);
+    }
+
+    @Override
+    public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {
+        super.exceptionCaught(ctx, cause);
+        cause.printStackTrace();

[kapishnikov, 2016/01/22 23:19:34]

It should be better to log the exception.

[mef, 2016/01/25 18:11:26]

Actually, for test usage it is probably better to re-throw, so it crashes and
burns.

[kapishnikov, 2016/01/25 19:47:09]

I agree. I was referring that we should use |sLogger| instead of
cause.printStackTrace().

[mef, 2016/01/25 22:31:39]

Hrm, |sLogger| is Http2FrameLogger, not a general logger.

[kapishnikov, 2016/01/26 00:00:25]

I think the exception will be logged anyways but
instead of 
cause.printStackTrace();
we can call:
android.util.Log.e("Http2TestHandler", "An exception was caught", cause);

[mef, 2016/01/26 15:42:16]

Done.

+        ctx.close();
+    }
+
+    private static Http2Headers responseHeadersFromRequestHeaders(Http2Headers requestHeaders) {

[kapishnikov, 2016/01/22 23:19:34]

Should we rename this method to something like
createEchoResponseHeadersFromRequestHeaders? Otherwise, it is not clear what the
method is doing without looking inside.

[mef, 2016/01/25 18:11:26]

Done.

+        // Make response headers by echoing request headers.
+        Http2Headers responseHeaders = new DefaultHttp2Headers().status(OK.codeAsText());
+        for (Map.Entry<CharSequence, CharSequence> header : requestHeaders) {
+            if (!header.getKey().toString().startsWith(":")) {
+                responseHeaders.add("echo-" + header.getKey(), header.getValue());
+            }
+        }
+
+        responseHeaders.add("echo-method", requestHeaders.get(":method").toString());
+        return responseHeaders;
+    }
+
+    private static String getEchoAllHeadersResponse(Http2Headers headers) {
+        StringBuilder response = new StringBuilder();
+        for (Map.Entry<CharSequence, CharSequence> header : headers) {
+            response.append(header.getKey() + ": " + header.getValue() + "\r\n");
+        }
+        return response.toString();
+    }
+
+    private static String getEchoHeaderResponse(Http2Headers headers) {
+        String[] split_path = headers.path().toString().split("\\?");
+        if (split_path.length <= 1) return "Header name not found.";
+
+        String header_name = split_path[1].toLowerCase(Locale.US);
+        if (headers.get(header_name) == null) return "Header not found:" + header_name;
+
+        return headers.get(header_name).toString();
+    }
+
+    private void doSendResponse(ChannelHandlerContext ctx, int streamId, ByteBuf payload) {
+        // Send a frame for the response status
+        encoder().writeHeaders(ctx, streamId, mResponseHeaders, 0, false, ctx.newPromise());
+        encoder().writeData(ctx, streamId, payload, 0, true, ctx.newPromise());
+        ctx.flush();
+    }
+
+    private void doEchoStream(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
+            int padding, boolean endOfStream) {
+        mEchoStream = true;
+        // Send a frame for the response headers.
+        encoder().writeHeaders(ctx, streamId, mResponseHeaders, 0, endOfStream, ctx.newPromise());
+        ctx.flush();
+    }
+
+    private void doEchoTrailers(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
+            int padding, boolean endOfStream) {
+        Http2Headers responseHeaders = new DefaultHttp2Headers().status(OK.codeAsText());
+        encoder().writeHeaders(ctx, streamId, responseHeaders, 0, false, ctx.newPromise());
+        encoder().writeData(ctx, streamId, RESPONSE_BYTES.duplicate(), 0, false, ctx.newPromise());
+        Http2Headers responseTrailers = mResponseHeaders.add("trailer", "value1", "Value2");
+        encoder().writeHeaders(ctx, streamId, responseTrailers, 0, true, ctx.newPromise());
+        ctx.flush();
+    }
+
+    @Override
+    public int onDataRead(ChannelHandlerContext ctx, int streamId, ByteBuf data, int padding,
+            boolean endOfStream) throws Http2Exception {
+        int processed = data.readableBytes() + padding;
+        if (mEchoStream) {
+            encoder().writeData(ctx, streamId, data.retain(), 0, endOfStream, ctx.newPromise());

[kapishnikov, 2016/01/22 23:19:33]

Do we need to retain data here? And if we do, should release it?

[mef, 2016/01/25 18:11:25]

IIUIC according to http://netty.io/wiki/reference-counted-objects.html outbound
messages are released by Netty.

+            ctx.flush();
+        } else if (endOfStream) {
+            doSendResponse(ctx, streamId, data.retain());

[kapishnikov, 2016/01/22 23:19:34]

In what scenario/tests this 'else-if' statement is going to be executed?

[mef, 2016/01/25 18:11:26]

If it is NOT echo-stream, then response is sent when end-of-stream flag is set
on request.

+        }
+        return processed;
+    }
+
+    @Override
+    public void onHeadersRead(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
+            int padding, boolean endOfStream) throws Http2Exception {
+        mResponseHeaders = responseHeadersFromRequestHeaders(headers);
+        String path = headers.path().toString();
+        if (path.startsWith("/echostream")) {
+            doEchoStream(ctx, streamId, headers, padding, endOfStream);
+        } else if (path.startsWith("/echotrailers")) {
+            doEchoTrailers(ctx, streamId, headers, padding, endOfStream);
+        } else if (endOfStream) {
+            mResponseHeaders = new DefaultHttp2Headers().status(OK.codeAsText());
+            ByteBuf content = ctx.alloc().buffer();
+            try {
+                if (path.startsWith("/echoallheaders")) {

[kapishnikov, 2016/01/22 23:19:33]

We should externalize all path constants like "echoallheaders" and reference
them from here and Http2TestServer.java, so they are always in sync.

[mef, 2016/01/25 18:11:26]

Done.

+                    ByteBufUtil.writeAscii(content, getEchoAllHeadersResponse(headers));
+                } else if (path.startsWith("/echoheader")) {
+                    ByteBufUtil.writeAscii(content, getEchoHeaderResponse(headers));
+                } else if (path.startsWith("/echomethod")) {
+                    ByteBufUtil.writeAscii(content, headers.method());
+                } else {
+                    content.writeBytes(RESPONSE_BYTES.duplicate());
+                    ByteBufUtil.writeAscii(content, " - via HTTP/2");
+                }
+            } catch (Exception e) {
+                ByteBufUtil.writeAscii(content, "Exception: " + e.toString());
+            }
+
+            doSendResponse(ctx, streamId, content);
+        }

[kapishnikov, 2016/01/22 23:19:34]

Should we add an error response if none of the conditions are true; I assume
otherwise, the test will wait till the timeout?

[mef, 2016/01/25 18:11:25]

It would just echo last received data buffer.

+    }
+
+    @Override
+    public void onHeadersRead(ChannelHandlerContext ctx, int streamId, Http2Headers headers,
+            int streamDependency, short weight, boolean exclusive, int padding, boolean endOfStream)
+            throws Http2Exception {
+        onHeadersRead(ctx, streamId, headers, padding, endOfStream);
+    }
+
+    @Override
+    public void onPriorityRead(ChannelHandlerContext ctx, int streamId, int streamDependency,
+            short weight, boolean exclusive) throws Http2Exception {}
+
+    @Override
+    public void onRstStreamRead(ChannelHandlerContext ctx, int streamId, long errorCode)
+            throws Http2Exception {}
+
+    @Override
+    public void onSettingsAckRead(ChannelHandlerContext ctx) throws Http2Exception {}
+
+    @Override
+    public void onSettingsRead(ChannelHandlerContext ctx, Http2Settings settings)
+            throws Http2Exception {}
+
+    @Override
+    public void onPingRead(ChannelHandlerContext ctx, ByteBuf data) throws Http2Exception {}
+
+    @Override
+    public void onPingAckRead(ChannelHandlerContext ctx, ByteBuf data) throws Http2Exception {}
+
+    @Override
+    public void onPushPromiseRead(ChannelHandlerContext ctx, int streamId, int promisedStreamId,
+            Http2Headers headers, int padding) throws Http2Exception {}
+
+    @Override
+    public void onGoAwayRead(ChannelHandlerContext ctx, int lastStreamId, long errorCode,
+            ByteBuf debugData) throws Http2Exception {}
+
+    @Override
+    public void onWindowUpdateRead(ChannelHandlerContext ctx, int streamId, int windowSizeIncrement)
+            throws Http2Exception {}
+
+    @Override
+    public void onUnknownFrame(ChannelHandlerContext ctx, byte frameType, int streamId,
+            Http2Flags flags, ByteBuf payload) throws Http2Exception {}
+}