example/plugins/lua-api/uncompress.lua

--  Licensed to the Apache Software Foundation (ASF) under one
--  or more contributor license agreements.  See the NOTICE file
--  distributed with this work for additional information
--  regarding copyright ownership.  The ASF licenses this file
--  to you under the Apache License, Version 2.0 (the
--  "License"); you may not use this file except in compliance
--  with the License.  You may obtain a copy of the License at
--
--  http://www.apache.org/licenses/LICENSE-2.0
--
--  Unless required by applicable law or agreed to in writing, software
--  distributed under the License is distributed on an "AS IS" BASIS,
--  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
--  See the License for the specific language governing permissions and
--  limitations under the License.

-- This example depends on "lua-zlib".
-- It uncompresses a gzipped content body and prints it out in debug log.
-- It can be added in remap.config for a remap rule with the lua plugin.

-- Setup Instructions
-- 1) install lua-zlib - v1.2

ts.add_package_cpath("/usr/lib/lua/5.1/?.so")

local zlib = require "zlib"

function upper_transform(data, eos)
  ts.ctx["text"] = ts.ctx["text"] .. data

  if eos == 1 then
    local stream = zlib.inflate()
    local inflated, eof, bytes_in, bytes_out = stream(ts.ctx["text"])
    if (eof == true) then
      ts.debug("==== eof ====")
    end
    ts.debug("==== bytes_in: " .. (bytes_in or ""))
    ts.debug("==== bytes_out:" .. (bytes_out or ""))
    ts.debug("==== uncompressed data begin ===")
    ts.debug(inflated or "no data")
    ts.debug("==== uncompressed data end ===")
  end

  return string.upper(data), eos
end

function do_remap()
  ts.hook(TS_LUA_RESPONSE_TRANSFORM, upper_transform)
  ts.ctx["text"] = ""
  return 0
end