Compression

Supported Algorithms

Please take a look at https://github.com/linkedin/rest.li/blob/master/r2/src/main/java/com/linkedin/r2/filter/compression/EncodingType.java to see which algorithms are currently supported.

NOTE

There is no hand-shake protocol between the server and the client to make sure that the server supports a particular compression algorithm. If the client sends a request compressed using an algorithm that the server is not configured with then the client request will fail as the server will not be able to decompress it

Using Guice

Server Configuration

Please take a look at: https://github.com/linkedin/rest.li/blob/master/examples/guice-server/server/src/main/java/com/example/fortune/inject/FortunesGuiceServletConfig.java to see how the server has to be configured.

In particular

FilterChain filterChain = FilterChains.create(
    new ServerCompressionFilter(new EncodingType[] { EncodingType.SNAPPY }),
    new SimpleLoggingFilter());

This instantiates a Rest.li server that supports SNAPPY compression. To support SNAPPY and GZIP for example, you would have to instantiate your server as follows:

FilterChain filterChain = FilterChains.create(
    new ServerCompressionFilter(new EncodingType[] { EncodingType.SNAPPY, EncodingType.GZIP }),
    new SimpleLoggingFilter());

When we say that a server supports a particular algorithm for compression, it means that the server can compress and decompress using that algorithm. When to compress and decompress is governed by the client request.

Client Configuration

Please take a look at: https://github.com/linkedin/rest.li/blob/master/examples/guice-server/client/src/main/java/com/example/fortune/RestLiFortunesClient.java to see how the client has to be configured.

In particular

    final HttpClientFactory http = new HttpClientFactory(FilterChains.create(
        new ClientCompressionFilter(EncodingType.IDENTITY, new EncodingType[]{ EncodingType.SNAPPY}, "*")
    ));

This snippet instructs Rest.li to use IDENTITY (a.k.a no compression) for requests to the server. In other words, the HTTP "Content-Encoding" header will be set to "identity". Thus, the first argument dictates the value of the "Content-Encoding" header.

The second argument dictates the value of the "Accept-Encoding" header. In the snippet above, each request to the server will have "Accept-Encoding" set to "snappy". Why every request? Because the third argument is set to "". "" means that each and every request to the server will have an "Accept-Encoding" header present. The third argument is a String of comma separated values, where the values can be "*", a method name, or a family.

• "*": add the "Accept-Encoding" header to all outgoing requests.
• a method name: add the "Accept-Encoding" header only for requests for the particular method. E.g. "get" would add it for get requests, "get, batch_get" would add it for get and batch_get requests etc.
• a family: add the "Accept-Encoding" header only for requests for a method that matches the family. A family is specified as method:. E.g. "action:" would add it for all actions, "finder:*" would add it for all finder requests etc.

The above three can be mixed. For example, to have compression on get, batch_get and all finders, the third argument would be "get, batch_get, finder:*"

Using Spring

Server Configuration

Client Configuration