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@TheRojam
Forked from iammehrabalam/decompress_body.lua
Created February 18, 2020 15:48
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-- Debian packages nginx-extras, lua-zlib required
ngx.ctx.max_chunk_size = tonumber(ngx.var.max_chunk_size)
ngx.ctx.max_body_size = tonumber(ngx.var.max_body_size)
function create_error_response (code, description)
local message = string.format('{"status":400,"statusReason":"Bad Request","code":%d,"exception":"","description":"%s","message":"HTTP 400 Bad Request"}', code, description)
ngx.status = ngx.HTTP_BAD_REQUEST
ngx.header.content_type = "application/json"
ngx.say(message)
ngx.exit(ngx.HTTP_OK)
end
function inflate_chunk (stream, chunk)
return stream(chunk)
end
function inflate_body (data)
local stream = require("zlib").inflate()
local buffer = ""
local chunk = ""
for index = 0, data:len(), ngx.ctx.max_chunk_size do
chunk = string.sub(data, index, index + ngx.ctx.max_chunk_size - 1)
local status, output, eof, bytes_in, bytes_out = pcall(stream, chunk)
if not status then
-- corrupted chunk
ngx.log(ngx.ERR, output)
create_error_response(4001, "Corrupted GZIP body")
end
if bytes_in == 0 and bytes_out == 0 then
-- body is not gzip compressed
create_error_response(4002, "Invalid GZIP body")
end
buffer = buffer .. output
if bytes_out > ngx.ctx.max_body_size then
-- uncompressed body too large
create_error_response(4003, "Uncompressed body too large")
end
end
return buffer
end
local content_encoding = ngx.req.get_headers()["Content-Encoding"]
ngx.log(ngx.ERR, content_encoding)
if content_encoding == "gzip" then
ngx.req.read_body()
local data = ngx.req.get_body_data()
ngx.log(ngx.ERR, data)
if data ~= '' then
ngx.log(ngx.ERR, data)
local new_data = inflate_body(data)
ngx.log(ngx.ERR, new_data)
ngx.req.clear_header("Content-Encoding")
ngx.req.clear_header("Content-Length")
ngx.req.set_body_data(new_data)
end
end
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