initDecompressor() — netty Function Reference

Source Code

codec-http2/src/main/java/io/netty/handler/codec/http2/DelegatingDecompressorFrameListener.java lines 239–281

    private void initDecompressor(ChannelHandlerContext ctx, int streamId, Http2Headers headers, boolean endOfStream)
            throws Http2Exception {
        final Http2Stream stream = connection.stream(streamId);
        if (stream == null) {
            return;
        }

        Http2Decompressor decompressor = decompressor(stream);
        if (decompressor == null && !endOfStream) {
            // Determine the content encoding.
            CharSequence contentEncoding = headers.get(CONTENT_ENCODING);
            if (contentEncoding == null) {
                contentEncoding = IDENTITY;
            }
            final EmbeddedChannel channel = newContentDecompressor(ctx, contentEncoding);
            if (channel != null) {
                decompressor = new Http2Decompressor(channel, connection, listener);
                stream.setProperty(propertyKey, decompressor);
                // Decode the content and remove or replace the existing headers
                // so that the message looks like a decoded message.
                CharSequence targetContentEncoding = getTargetContentEncoding(contentEncoding);
                if (IDENTITY.contentEqualsIgnoreCase(targetContentEncoding)) {
                    headers.remove(CONTENT_ENCODING);
                } else {
                    headers.set(CONTENT_ENCODING, targetContentEncoding);
                }
            }
        }

        if (decompressor != null) {
            // The content length will be for the compressed data. Since we will decompress the data
            // this content-length will not be correct. Instead of queuing messages or delaying sending
            // header frames just remove the content-length header.
            headers.remove(CONTENT_LENGTH);

            // The first time that we initialize a decompressor, decorate the local flow controller to
            // properly convert consumed bytes.
            if (!flowControllerInitialized) {
                flowControllerInitialized = true;
                connection.local().flowController(new ConsumedBytesConverter(connection.local().flowController()));
            }
        }
    }