Environment
Environment variables
The table provides a list of environment variables defined in the Cloud Functions runtime and available to a function. You cannot override these.
| Key | Value |
|---|---|
_HANDLER |
The handler location specified for the function. |
AWS_LAMBDA_RUNTIME_API |
The runtime host and API port. |
LAMBDA_RUNTIME_DIR |
Path to runtime libraries. |
LAMBDA_TASK_ROOT |
Path to folder containing your function's files. |
PATH |
Set of folders containing the executables. |
LD_LIBRARY_PATH |
Set of folders containing the dynamic libraries. |
You can add other environment variables when creating a function version. The limit for maximum environment variable size, including variable names, is 4 KB.
You cannot calculate environment variables. Environment variable values are string constants. You can only calculate these within function code.
You can retrieve environment variables using standard programming language tools.
Certificate for accessing managed databases
The environment has an SSL certificate available for accessing managed databases from your code. The certificate is stored in the /usr/local/share/ca-certificates/yandex-internal-ca.crt file.
User files
User files are stored in two directories:
-
/function/code: The user's working directory. It contains all the code of your function and all the files uploaded as a ZIP archive. You can use a relative path to access it. -
/tmp: directory for temporary files. It is used by the service to optimize repeat function calls that are sequentially processed by one of its instances. When a function instance runs its course, its data in/tmpare deleted. The maximum size of temporary files is limited to 512 MB.When creating a function version, you can allocate some RAM of a function instance for the
tmpdirectory. The specified amount of RAM will thus be mounted as a RAM disk to the/tmpdirectory. A function version must have at least 1 GB of RAM.If you enable Allocate memory for the /tmp directory, preloaded runtime environments start as regular ones.
Dynamic libraries
If your functions require dynamic libraries to run, you can add them to a ZIP archive placing them in the /shared-libs directory at the root of the archive. The directory will be added to the LD_LIBRARY_PATH environment variable.
You must build the dynamic libraries on Ubuntu 18.04 LTS and link them using libc version 2.27.