StreamingFast Python Example

This simple program demonstrates how easy it is to stream full block details using StreamingFast gRPC API:

• Request a token from our authentication API
• Creates a gRPC connection with credentials
• Instantiates a BlockStream client
• Start a stream of blocks
• Prints the blocks received

Requirements

You will need to have Python3 (>= 3.5+) as well as virtualenv and pip >= 15.0+.

We use a virtual environment for this example, all dependencies are listed in the requirements.txt at the root of this project.

Quickstart

First of all, visit https://streamingfast.io/ to get a free API key for your project.

First, clone this repository to your work folder:

git clone https://github.com/streamingfast/example-python.git
cd example-python

Setup the virtual environment and pull all dependencies:

./install_deps.sh

Once your environment is setup properly, simply run the main.py script:

python3 main.py YOUR_API_KEY_HERE

By default it prints light details about the blocks, use the --full flag to print the full block in JSON:

python3 main.py YOUR_API_KEY_HERE --full

Note The default Protobuf to JSON will prints the various bytes type using base64 encoding, this is unfortunate as it makes reading it in the JSON harder. If you find a quick option to print it as hexadecimal, open a PR we will be happy to merge it in.

Further details about StreamingFast capabilities can be found on our Golang client at https://github.com/streamingfast/streamingfast-client#query-language.

Protobuf

The protocol buffers are already generated, the generate_proto.sh is able to regenerate them if needed, it showcases also the command the can be used to generate them back.

The script expects by default that the proto definitions are sibling of this project, looking like:

projects
├── example-python
├── proto
└── proto-ethereum

To re-generate, simply do:

./generate_proto.sh