Lua Requires Chilkat v11.0.0+

Get Size of File on Web Server

See more HTTP Examples

Demonstrates how to send a HEAD request to fetch information about a file on a web server, which hopefully includes the Content-Length in the response header. Lua

local chilkat = require("chilkat")

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

local http = chilkat.Http.new()

local resp = chilkat.HttpResponse.new()
local success = http:http_no_body("HEAD", "https://nodejs.org/dist/v10.16.1/node-v10.16.1-win-x64.zip", resp)
if not success then
    print(http.last_error_text)
    return
end

-- Examine the response header.
print(resp.header)

-- Here is a sample response header:

-- Date: Thu, 01 Aug 2019 12:47:27 GMT
-- Content-Type: application/zip
-- Content-Length: 17457922
-- Connection: keep-alive
-- Set-Cookie: __cfduid=da5b78dcdd8171683c5a578eb9c9f88c81564663647; expires=Fri, 31-Jul-20 12:47:27 GMT; path=/; domain=.nodejs.org; HttpOnly
-- Last-Modified: Wed, 31 Jul 2019 18:21:57 GMT
-- ETag: "5d41dc45-10a6302"
-- Accept-Ranges: bytes
-- Expect-CT: max-age=604800, report-uri="https://report-uri.cloudflare.com/cdn-cgi/beacon/expect-ct"
-- Server: cloudflare
-- CF-RAY: 4ff7ebb32ac4e1e2-ORD

-- Get the Content-Length header.
local contentLengthStr = resp:get_header_field("Content-Length")
-- If the header exists...
if resp.last_method_success then
    print("Content-Length: " .. contentLengthStr)
    -- Your application can convert the contentLengthStr to an integer and then use it....
end