Python 3 bindings for the AWS Common Runtime.
- API documentation
- Development guide for contributors to aws-crt-python's source code.
This library is licensed under the Apache 2.0 License.
- Python 3.7+
To install from pip:
python3 -m pip install awscrt
To install from Github:
git clone https://github.com/awslabs/aws-crt-python.git
cd aws-crt-python
git submodule update --init
python3 -m pip install .
To use from your Python application, declare awscrt
as a dependency in your setup.py
file.
aws-crt-python does not use OpenSSL for TLS. On Apple and Windows devices, the OS's default TLS library is used. On Unix devices, s2n-tls is used. But s2n-tls uses libcrypto, the cryptography math library bundled with OpenSSL.
To simplify installation, aws-crt-python has its own copy of libcrypto. This lets you install a wheel from PyPI without having OpenSSL installed. Unix wheels on PyPI come with libcrypto statically compiled in. Code to build libcrypto comes from AWS-LC. AWS-LC's code is included in the PyPI source package, and the git repository includes it as a submodule.
If you need aws-crt-python to use the libcrypto included on your system,
set environment variable AWS_CRT_BUILD_USE_SYSTEM_LIBCRYPTO=1
while building from source:
AWS_CRT_BUILD_USE_SYSTEM_LIBCRYPTO=1 python3 -m pip install --no-binary :all: --verbose awscrt
( --no-binary :all:
ensures you do not use the precompiled wheel from PyPI)
You can ignore all this on Windows and Apple platforms, where aws-crt-python uses the OS's default libraries for TLS and cryptography math.
Please note that on Mac, once a private key is used with a certificate, that certificate-key pair is imported into the Mac Keychain. All subsequent uses of that certificate will use the stored private key and ignore anything passed in programmatically. Beginning in v0.6.2, when a stored private key from the Keychain is used, the following will be logged at the "info" log level:
static: certificate has an existing certificate-key pair that was previously imported into the Keychain. Using key from Keychain instead of the one provided.
You can enable the crash handler by setting the environment variable AWS_CRT_CRASH_HANDLER=1
. This will print the callstack to stderr
in the event of a fatal error.