Lua Requires Chilkat v11.0.0+
Lua
Bidirectional Sockets (TLS or non-TLS, simultaneous reading and writing a connection)
See more Socket/SSL/TLS Examples
This example demonstrates how to simultaneously read/write on a single socket connection.Chilkat Lua Downloads
-- In the following call to loadlib, change the path (./chilkat.dll) to the relative or absolute directory where the chilkat.dll, chilkat.so, or chilkat.dylib is located.
chilkat = assert(package.loadlib("./chilkat.dll", "luaopen_chilkat"))()
print(chilkat._VERSION)
local success = false
-- This example requires the Chilkat API to have been previously unlocked.
-- See Global Unlock Sample for sample code.
local tlsRead = chilkat.newSocket{}
-- We'll just use an HTTPS server for this example...
local bUseTls = true
local maxWaitMs = 5000
success = tlsRead:Connect("www.chilkatsoft.com",443,bUseTls,maxWaitMs)
if success == false then
print(tlsRead:LastErrorText())
end
-- Chilkat classes are thread-safe. This means that only one method call can be active
-- at a time for a given object instance. It would seem that this would prevent the possibility
-- to simultaneously read/write a given connection because it would require two method calls
-- to be simultaneously active: one for reading and one for writing.
--
-- There's a trick to doing it...
--
-- The DupSocket method is provided to get a new object instance that shares the same socket
-- connection. This allows for the coarse-grained object-level thread safety to be maintained,
-- while finer-grained thread-safety mechanisms keep things kosher internally.
-- One object will be used for reading, and the cloned socket is used for writing.
-- It doesn't matter which -- you can use the cloned socket for reading or the original for writing.
-- However.. if you try to read simultneously from both the original and cloned objects at the same
-- time, then one will block until the other finishes. (This is because of the finer-grained thread
-- safety internally.) The same is true if you try to write both socket objects simultaneously.
local tlsWrite = chilkat.newSocket{}
success = tlsRead:DupSocket(tlsWrite)
if success == false then
print(tlsRead:LastErrorText())
end
-- Let's start an async read on the socket. Nothing will be arriving until we actually send the GET
-- request and the server responds. This will read until the end of the HTTP response header.
local task = tlsRead:ReceiveUntilMatchAsync("\r\n\r\n")
task:Run()
-- Now send the request. This should not block because the read is happening on the tlsRead object.
local httpGetReq = "GET / HTTP/1.1\r\nHost: www.chilkatsoft.com\r\n\r\n"
success = tlsWrite:SendString(httpGetReq)
-- Assuming success for the example...
-- Wait for the read task to finish.
-- The true/false returned by Wait applies to the Wait method call, not the task.
maxWaitMs = 5000
success = task:Wait(maxWaitMs)
if !success || (task:StatusInt() ~= 7) || (task:TaskSuccess() ~= true) then
if !success then
-- The task.LastErrorText applies to the Wait method call.
print(task:LastErrorText())
else
-- The ResultErrorText applies to the underlying task method call (i.e. the Connect)
print(task:Status())
print(task:ResultErrorText())
end
end
-- Examine the received HTTP response header:
print("HTTP response header:")
print(task:GetResultString())
-- We should get a response that looks like this:
-- HTTP response header:
-- HTTP/1.1 200 OK
-- Cache-Control: private
-- Content-Length: 7477
-- Content-Type: text/html
-- Server: Microsoft-IIS/8.5
-- Set-Cookie: ASPSESSIONIDSWDSTRTQ=BBNMIKGCHFJNILFFPLDIOGDE; secure; path=/
-- X-Powered-By: ASP.NET
-- X-Powered-By-Plesk: PleskWin
-- Date: Thu, 06 Apr 2017 12:03:30 GMT
-- Forget about the remainder of the HTTP response... The example was only to demonstrate
-- simultaneous reading/writing..
maxWaitMs = 20
tlsRead:Close(maxWaitMs)