@atercattus This is a known limitation in LuaJIT (and the standard Lua 5.1 interpreter) that the require builtin is currently implemented as a C builtin across which you cannot initiate a yield. A work-around is to put your coroutine operations in a function in your Lua module and let the caller call your function explicitly after require. Attempt to yield across metamethod/C-call boundary. Attempt to yield across metamethod/C-call boundary. The function pcall is actually a C function which. I am aware of the limitation of yielding across C-call boundaries. Run.lua:6 test.lua:5: in main chunk false attempt to yield across metamethod/C-call boundary.

Lua Coro-net Attempt To Yield Across C-call Boundary Without
Lua Coro-net Attempt To Yield Across C-call Boundary Will
Lua Coro-net Attempt To Yield Across C-call Boundary Using

ZeroBrane Studio has already been used to debug various Lua engines -- game frameworks (like Corona, Gideros, Moai, Love2d), home automation devices, wireshark scripts, Adobe Lightroom plugins, and more -- but there have been several Lua environments that I haven't tried it on. One of them is OpenResty/Nginx Lua scripts. OpenResty is a web application server built around nginx, a very fast web server, that provides non-blocking IO with various backends (Redis, Memcached, MySQL, HTTP servers, and others) and supports Lua as its scripting language.

I first tried to use the non-blocking socket API that OpenResty provides, but couldn't get the debugging to work because socket calls that were supposed to be blocking were returning too early, which was breaking the interaction between the debugger in the application and the IDE. Based on advice from Yichun Zhang (agentzh), the maintainer of the OpenResty bundle, I then tried to use the same luasocket library that ZeroBrane Studio is using and got it all working. These are the steps you can follow to try it yourself:

ZeroBrane Studio configuration.

'attempt to yield across C-call boundary' occur while connect, The LuaJIT implementation does not support yielding across the C function call boundary, just like the standard Lua 5.1 interpreter. Your work-around indeed It seems that the require function is implemented as a C function, which cannot be yielded in the middle of the require call. True C coroutine semantics mean you can yield from a coroutine across a C call boundary and resume back to it. Try using LuaJIT instead of the standard Lua interpreter. It uses a fully resumable VM meaning the boundary is not an issue. Try using Lua 5.2. It features yieldable pcall and metamethods which means that it can handle your problem.

1. Get ZeroBrane Studio. These instructions are for Windows, but the debugging should work on Linux and OSX as well.

2. Start ZBS (zbstudio.exe or zbstudio.sh) and start the debugger Project | Start Debugger Server.

OpenResty configuration.

1. I'm using a very basic config (<NGINX>/conf/nginx.conf):

Make sure you replace <ZBS> with the actual path to ZeroBrane Studio location. If you are running on OSX, replace ?.dll with ?.dylib and if you are running on Linux, replace bin/clibs/?.dll with either bin/linux/x86/clibs/?.so or bin/linux/x64/clibs/?.so depending on your platform.

2. Create the file we are going to debug (<NGINX>/lua/content.lua), which may look like this:

Note that start() call takes the IP of the computer running the IDE. It uses 'localhost' by default, but since your nginx instance is running there, you will need to specify the IP address of the computer running the IDE (in my case it is 192.168.1.22).

3. Open this file (<NGINX>/lua/content.lua) file in the IDE and set the project directory to lua folder by going to Project | Project Directory | Set From Current File.

Script debugging.

Now start nginx and go to http://localhost/hellolua. If everything is right, you should see ZeroBrane Studio activated with the green arrow pointing to the second line (similar to what can be seen in the screenshot above). You can now set breakpoints, step through the code, look at the stack and so on.

You can also go to the remote console and run any ngx command there. For example, if you run ngx.say('Message from console') (as shown in the screenshot), you will see this text in the output after the script is done.

If you get 'attempt to yield across C-call boundary' error in Nginx logs when you start debugging, try with a more recent ZeroBrane Studio (0.70+) as it includes several improvements that make debugging to work with recent versions of OpenResty.

OpenResty configuration for remote debugging.

The following steps are only needed if you configure OpenResty/Nginx for remote debugging when Nginx runs on one machine and ZeroBrane Studio runs on another one. When you run both on the same machine, Nginx is using modules included with ZeroBrane Studio as those are referenced by lua_package_path and lua_package_cpath directives.

1. Copy the debugger (mobdebug.lua) and socket files. Go to <ZBS>/lualibs/mobdebug/ and copy mobdebug.lua to <NGINX>/lua/mobdebug.lua; also copy <ZBS>/lualibs/socket.lua to <NGINX>/lua/. After all this is done, the content of lua folder is going to look like this:

2. Copy <ZBS>/bin/clibs/socket/core.dll to <NGINX>/socket/core.dll (core.dylib and core.so files are in the bin folder as well).

You should get a copy of my slick ZeroBrane Studio IDE and follow me on twitterhere.

17.03.2018, 10:03

How can I create custom package for LM?
I need custom websocket connections with TV and other stuff and I want to use this connection inside LUA resident or event scripts.
The main idea is I create a package which works as HTTP server on some local port and it has and ability to create websocket clients inside.
e.g.
event script

Lua coro-net attempt to yield across c-call boundary using

Lua Coro-net Attempt To Yield Across C-call Boundary Without

ws = require('lua.websocket') 
tvConnection, err = ws.connect('ws://my.tv.ip:3000') -- (blocking with t/o) send to local HTTP server
 -- a command to connect if no connection
tvConnection.send('raw data') -- send text or array of bytes to 'ws://my.tv.ip:3000'

resident script 0 sec

Lua Coro-net Attempt To Yield Across C-call Boundary Will

ws = require('lua.websocket')
tvConnection, err = ws.connect('ws://my.tv.ip:3000') -- (blocking with t/o) send to local HTTP server 
 -- a command to connect if no connection
data = tvConnection.receive() -- receive array of data came from 'ws://my.tv.ip:3000'

Could you please create kind of this stuff? Or give me instruction how to build own package, I know C/C++, Golang, JS, Lua

Lua Coro-net Attempt To Yield Across C-call Boundary Using

Thank you in advance!