Lua Requires Chilkat v10.1.0+

REST Receive Response in Chunks

See more REST Examples

Demonstrates how to receive a REST HTTP response in chunks. Lua

local chilkat = require("chilkat")

-- This example requires the Chilkat API to have been previously unlocked.
-- See Global Unlock Sample for sample code.

local rest = chilkat.Rest.new()

-- Connect to the web server
local bTls = true
local port = 443
local bAutoReconnect = true
local success = rest:connect("chilkatsoft.com", port, bTls, bAutoReconnect)
if not success then
    print(rest.last_error_text)
    return
end

-- Send the request.
-- This can be *any* kind of request: POST, GET, PUT, etc. using *any* of the Chilkat REST methods that send requests.
-- For this example, we'll just GET a simple XML document that is about 274K in size.

success = rest:send_req_no_body("GET", "/hamlet.xml")
if not success then
    print(rest.last_error_text)
    return
end

-- Get the response header.
local statusCode = rest:read_response_header()
if statusCode < 0 then
    print(rest.last_error_text)
    return
end

print("response status code = " .. statusCode)

local outputFile = "c:/temp/qa_output/hamlet.xml"

local fac = chilkat.FileAccess.new()
success = fac:open_for_write(outputFile)
if statusCode < 0 then
    print(fac.last_error_text)
    return
end

-- Get the response in chunks.
-- (Note: There are more efficient ways to simply download a file from a web server, such as by calling Chilkat's Http.Download method.
-- The purpose of this method is to show how to receive a response chunk-by-chunk.)
local bd = chilkat.BinData.new()
local status = 1
while status == 1 do
    -- Read a minimum of 16000 bytes.
    -- Note: Because of TLS message lengths, or the possibility of the response being either compressed (gzip/deflate) or in the HTTP chunked encoding,
    -- the amount of data received in each call can be greater than the specified min size.
    -- Chilkat will return from the call as soon as it has received an amount equal to or more than the specified size,
    -- except for the very last chunk, which can be less that the min size or even 0 bytes.

    -- The status will be one of three values:
    -- -1 = error
    -- 0 = received the last chunk of the response.
    -- 1 = received a chunk, and more chunks are coming..

    -- The received data is *appended* to the contents of the BinData object.
    status = rest:read_resp_chunk_bd(16000, bd)
    if status >= 0 then
        print("Received chunk: " .. bd.num_bytes .. " bytes")
        fac:file_write_bd(bd, 0, 0)
        bd:clear()
    end
end

fac:file_close()

print("Success.")