Debugging a node.js app in windows (no eclipse)

If you don’t want to install eclipse and google dev tools to debug your node.js app you may use node inspector which is a node.js app that resembles google chrome’s dev tools. You start your node app passing the –debug-brk (or –debug if you don’t care about the first lines of code) and then fire up node inspector and debug the app. I actually have node inspector running all the time and I simply refresh the webpage when I reload the application.

Happy debugging…

strcasecmp: identifier not found when porting from linux to windows

Ever tried to port from linux to windows and got the :

error C3861: 'strcasecmp': identifier not found

The easiest workaround is to add a  conditional define (visual studio add the –D _WIN32 or _WIN64 depending your OS) and define the following mappings:

#if defined(_WIN32) || defined(_WIN64)
  #define snprintf _snprintf
  #define vsnprintf _vsnprintf
  #define strcasecmp _stricmp
  #define strncasecmp _strnicmp
#endif

Another common missing identifier is the Uint which can be solved adding:

#define uint=unsigned int

Debugging native node modules loading failure on windows

If you ever need to build a module that requires another library (e.g. openssl, ict, expat etc) you may receive an “Out of memory” error when you require the file. This is unfortunately a generic error on windows but you can fire up visual studio and debug node (attaching to a process) and you can can see there the exact system error number (sys_errno) by adding a breakpoint in deps\uv\src\win\error.c when uv translates the error code (uv_translate_sys_error).

Node.js modules cross platform compilation using gyp

Update: I have made a pull request where you can find the updated tools discussed in this article, located here
Node.js has been using waf (node-waf) to configure and build modules up to version 0.4. From v0.6 and on, the team has moved on to gyp (Generate Your Projects) which seems to be a bit more promising when it comes to cross platform compilation. This post shows how to create a simply gyp file to build your own custom native node.js modules and provides some scripts to automate the project generation process.

Building a simple native nodejs module on windows from command line

Setting up a visual studio project to just build a simple native hello world node module is an overkill and there is a simpler way to do that by using the visual studio command prompt directly. Here you may find the required commands you have to issue, plus a vcbuild.bat file that does the whole thing at once.

Building native modules for nodeJs 0.6+ with visual studio

Since version 0.6 node js supports windows native builds which allows the windows dev to use visual studio to build both nodejs and the modules. In order to make a simple node module in visual studio you will have to link the obj file with the node.lib file that is generated when you compile the nodejs on visual studio. Here is a detailed walkthrough on how to successfully build a native node module in visual studio 2010.