refactor(tools): separate gzip functions from tools.utils (#11875)

kong-3.6.0-0.rockspec

@@ -164,6 +164,7 @@ build = {
     ["kong.tools.protobuf"] = "kong/tools/protobuf.lua",
     ["kong.tools.mime_type"] = "kong/tools/mime_type.lua",
     ["kong.tools.request_aware_table"] = "kong/tools/request_aware_table.lua",
+    ["kong.tools.gzip"] = "kong/tools/gzip.lua",
     ["kong.tools.string"] = "kong/tools/string.lua",
     ["kong.tools.table"] = "kong/tools/table.lua",
     ["kong.tools.sha256"] = "kong/tools/sha256.lua",

kong/tools/gzip.lua

@@ -0,0 +1,62 @@
+local buffer = require "string.buffer"
+local zlib = require "ffi-zlib"
+
+
+local inflate_gzip  = zlib.inflateGzip
+local deflate_gzip  = zlib.deflateGzip
+
+
+local _M = {}
+
+
+-- lua-ffi-zlib allocated buffer of length +1,
+-- so use 64KB - 1 instead
+local GZIP_CHUNK_SIZE = 65535
+
+
+local function read_input_buffer(input_buffer)
+  return function(size)
+    local data = input_buffer:get(size)
+    return data ~= "" and data or nil
+  end
+end
+
+
+local function write_output_buffer(output_buffer)
+  return function(data)
+    return output_buffer:put(data)
+  end
+end
+
+
+local function gzip_helper(inflate_or_deflate, input)
+  local input_buffer = buffer.new(0):set(input)
+  local output_buffer = buffer.new()
+  local ok, err = inflate_or_deflate(read_input_buffer(input_buffer),
+                                     write_output_buffer(output_buffer),
+                                     GZIP_CHUNK_SIZE)
+  if not ok then
+    return nil, err
+  end
+
+  return output_buffer:get()
+end
+
+
+--- Gzip compress the content of a string
+-- @tparam string str the uncompressed string
+-- @return gz (string) of the compressed content, or nil, err to if an error occurs
+function _M.deflate_gzip(str)
+  return gzip_helper(deflate_gzip, str)
+end
+
+
+--- Gzip decompress the content of a string
+-- @tparam string gz the Gzip compressed string
+-- @return str (string) of the decompressed content, or nil, err to if an error occurs
+function _M.inflate_gzip(gz)
+  return gzip_helper(inflate_gzip, gz)
+end
+
+
+return _M

kong/tools/utils.lua

@@ -10,12 +10,10 @@
 
 local ffi = require "ffi"
 local uuid = require "resty.jit-uuid"
-local buffer = require "string.buffer"
 local pl_stringx = require "pl.stringx"
 local pl_utils = require "pl.utils"
 local pl_path = require "pl.path"
 local pl_file = require "pl.file"
-local zlib = require "ffi-zlib"
 
 local C             = ffi.C
 local ffi_new       = ffi.new
@@ -35,8 +33,6 @@ local join          = pl_stringx.join
 local split         = pl_stringx.split
 local re_find       = ngx.re.find
 local re_match      = ngx.re.match
-local inflate_gzip  = zlib.inflateGzip
-local deflate_gzip  = zlib.deflateGzip
 local setmetatable  = setmetatable
 
 ffi.cdef[[
@@ -1038,53 +1034,6 @@ do
 end
 
 
-do
-  -- lua-ffi-zlib allocated buffer of length +1,
-  -- so use 64KB - 1 instead
-  local GZIP_CHUNK_SIZE = 65535
-
-  local function read_input_buffer(input_buffer)
-    return function(size)
-      local data = input_buffer:get(size)
-      return data ~= "" and data or nil
-    end
-  end
-
-  local function write_output_buffer(output_buffer)
-    return function(data)
-      return output_buffer:put(data)
-    end
-  end
-
-  local function gzip_helper(inflate_or_deflate, input)
-    local input_buffer = buffer.new(0):set(input)
-    local output_buffer = buffer.new()
-    local ok, err = inflate_or_deflate(read_input_buffer(input_buffer),
-                                       write_output_buffer(output_buffer),
-                                       GZIP_CHUNK_SIZE)
-    if not ok then
-      return nil, err
-    end
-
-    return output_buffer:get()
-  end
-
-  --- Gzip compress the content of a string
-  -- @tparam string str the uncompressed string
-  -- @return gz (string) of the compressed content, or nil, err to if an error occurs
-  function _M.deflate_gzip(str)
-    return gzip_helper(deflate_gzip, str)
-  end
-
-  --- Gzip decompress the content of a string
-  -- @tparam string gz the Gzip compressed string
-  -- @return str (string) of the decompressed content, or nil, err to if an error occurs
-  function _M.inflate_gzip(gz)
-    return gzip_helper(inflate_gzip, gz)
-  end
-end
-
-
 local get_mime_type
 local get_response_type
 local get_error_template
@@ -1432,6 +1381,7 @@ _M.get_updated_monotonic_ms = get_updated_monotonic_ms
 
 do
   local modules = {
+    "kong.tools.gzip",
     "kong.tools.table",
     "kong.tools.sha256",
     "kong.tools.yield",