lambda-client

Requirements

Python 3.6 or later

To install, you need Python 3.6 or later and PIP.

If you are using Windows, make sure to tick the 'Add Python to environment variables' tickbox under Advanced Options when you install Python, or otherwise add Python to your system PATH.

Then:

pip3 install -r requirements.txt

Configuration

Edit lambda.conf and fill in your private and public IDs:

[SECRET]
PrivateKey = <your private id>
PublicKey = <your public id>

NB: if you change lambda.conf, you must restart the daemon process for the changes to take effect.

Usage

Basic usage

First, run the daemon:

./lambdad.py

Then, in a separate terminal, you can execute lambda-cli.py commands. For example:

./lambda-cli.py getblockchaininfo

To get help, run ./lambda-cli.py --help or ./lambda-cli.py <subcommand> --help.

If you are running Windows and ./lambda-cli.py getblockchainfo creates a console that disappears immediately, run:

python.exe lambda-cli.py getblockchainfo

Accessing JSON fields

With any command that returns a JSON output, you can access fields in the output directly from lambda-cli.py. For example:

./lambda-cli.py getmininginfo puzzle
./lambda-cli.py getblockchaininfo block_ts
./lambda-cli.py getbalances 42

Historic blocks

The getblockchaininfo, getmininginfo, getbalances and getbalance commands return information pertaining to the current block. To retrieve information about previous blocks, use the getblockinfo subcommand. For example:

# Get info about current block
./lambda-cli.py getblockinfo
# Get info about previous blocks (1 and 3)
./lambda-cli.py getblockinfo 1
./lambda-cli.py getblockinfo 1 block_ts
./lambda-cli.py getblockinfo 3 balances 42

blocks/ folder on disk

Your lambdad.py daemon also saves the output of getblockinfo on disk, in the blocks/ folder relative to where ./lambdad.py is called from. (You can change DataDir in lambda.conf if you want to place it somewhere else.) You might find this easier to integrate into your workflow than the JSON-RPC interface (explained below).

Checking your own balance

If you have set-up your PublicKey correctly in lambda.conf, running ./lambda-cli.py getbalance will return your current balance.

If you set a different team's PublicKey, your submissions will still work, but running getbalance will return that team's balance rather than your own.

Submitting solutions to block task and puzzle

Similarly, if you have set-up your PrivateKey, you can use lambda-cli.py to submit solutions to the block task and puzzle:

./lambda-cli.py submit --help
# the actual file names don't matter; file extensions do (to help you catch mistakes)
./lambda-cli.py submit 3 path_to_task.sol path_to_puzzle_sol.desc

NB: paths passed to ./lambda-cli.py submit are interpreted relative to the daemon process, not to the CLI process. To keep things simple, we recommend running both in the same directory.

Note that providing the block number you are submitting for is mandatory. This ensures you always submit to the block you intend and helps prevent mistakes, since submissions are final.

JSON-RPC

You do not have to use lambda-cli.py (although we recommend it). The lambdad.py process exposes a standard JSON-RPC interface on port 8332.

Your favourite programming language likely has a library to interact with JSON-RPC servers, but we cannot provide any support with that. However, here are some examples of how to talk to the JSON-RPC lambdad.py interface via cURL:

curl --data-binary '{"jsonrpc":"2.0","id":"curl","method":"getblockchaininfo","params":[]}' -H 'content-type:text/plain;' http://127.0.0.1:8332/

curl --data-binary '{"jsonrpc":"2.0","id":"curl","method":"getbalance","params":[42]}' -H 'content-type:text/plain;' http://127.0.0.1:8332/

curl --data-binary '{"jsonrpc":"2.0","id":"curl","method":"getblockinfo","params":[1]}' -H 'content-type:text/plain;' http://127.0.0.1:8332/

The return value of the called method is in the result item of the output.

If you end up using some clever JSON-RPC contraption, do let us know in the README.md of your final submission! Happy hacking :-)