JavaScript SDK

Contact us about the availability of the JavaScript SDK.

JavaScript instrumentation

The Antithesis platform can automatically instrument JavaScript code by performing a source transformation after you’ve sent it to us. No changes to your source code or build system are required. Our instrumentor assumes by default that you are using NodeJS as your runtime – contact us if you’d like to use a different runtime. We do not support instrumenting JavaScript code that runs in a browser.

NodeJS

Place directories, files, or symlinks to the code you want instrumented or cataloged in the directory /opt/antithesis/catalog/ within your container image. Antithesis will follow all symlinks while resolving the path to the cataloging directory.

However, it will follow only one symlink deep into each item placed within /opt/antithesis/catalog/. That is, you should not symlink to a symlink.

Example cataloging directory:

> ln -s /usr/share/my_app /opt/antithesis/catalog 

> ls -lAh /opt/antithesis/catalog
lrwxrwxrwx  1 me users 4 Apr  8 17:32 /opt/antithesis/catalog -> /usr/share/my_app

> ls -lAh /opt/antithesis/catalog/
-rwxr-xr-x  1 me users  20K Apr  8 17:33 dotnet_file.dll
lrwxrwxrwx  1 me users 27 Apr  8 17:52 more_files -> /opt/my_project/java_files 
-rwxr-xr-x  1 me users  10K Apr  8 17:33 python_script.py

> ls -lA /opt/antithesis/catalog/more_files/
-rw-r--r--  1 me users  16K Apr  8 17:51 main.jar
lrwxrwxrwx  1 me users  16K Apr  8 17:51 my_other.jar -> /some/other/place.jar

Based on the example above, the following files would be instrumented:

• dotnet_file.dll
• python_script.py
• main.jar

Ignored files:

• my_other.jar - this will be ignored as we already encountered one symlink when traversing down from opt/antithesis/catalog/more_files.

When instrumenting Javascript, the instrumentor will search for directories containing node_modules and recursively instrument all of the code within said directories; however, it will by default exclude everything in node_modules and some standard configuration files that happen to be implemented as JavaScript (for instance eslint.config.js). It follows that vendored dependencies will be instrumented by default.

For dependency management, Antithesis supports require by default, but can be configured to support import – email us at support@antithesis.com and we’ll flip the setting for your account.

JS-target languages

Antithesis can instrument projects in JavaScript-target languages such as TypeScript if you provide us with transpiled JavaScript code. Transpilation must happen before you send us the code (as part of your build process), rather than at service startup.

Symbolization

Antithesis will automatically gather the symbol information from your code. You do not need to separately provide us with symbol files.

Help

Contact us if you need help with this.