cardano-shell

|Coverage Status|

|"master" Build status|

This is the cardano-shell project. This project uses Github issues for tracking the project progress.

About

This "node shell" is a thin layer of functionality surrounding the node. It's a thin layer which brings all the other modules working together and makes sure that they have the required resources (configuration, exception handling, monitoring, logging, ...).

|cardano-shell|

From the top level, the "node shell" contains some of the following:

• startup initialization
• configuration loading
• process monitoring

Some of it responsibilities are the cross-cutting concerns like:

• logging
• monitoring
• configuration
• exception handling
• launcher (it's related to startup, but we need to simplify it if possible)

|cardano-shell-responsibilities|

For example, we can see some of the modules cardano-shell integrates with:

• network layer
• blockchain layer
• ledger layer
• logging layer
• monitoring layer
• wallet (backend) layer

|cardano-shell-integration|

Any module that requires a substantial amount of logging or monitoring, should provide such resources iself. For example, 1 thread per module should be enough from the point of view of cardano-shell. If, for example, network module requires 5 threads, it should provide such resources itself.

For serving the module functionality, we can use withAsync for top-level calls which is resource/exception safe. The option left for discussion is whether we should have a need for a restart on a module/process.

For more info about the architecture, please take a look at here <ARCHITECTURE.md>. For more info about the launcher, please take a look at here <LAUNCHER.md>.

Example

For example, we can get a chain generator to try to integrate with logging output and cardano-shell should be a piece of code that glues them together, providing a very simple (random) chain generation and it's output. We need to remove a lot of things that are there in the old version. For example, the Servant API.

People

Core seems to be split into:

• blockchain
• ledger

Currently, the (relevant) team structure seems to be:

• networking - Duncan
• core - Eric
• logging & monitoring - Alexander

Building

You can build the project using Stack or Nix.

Stack

::

   stack build --fast

.. _stack--nix:

Stack + Nix

::

stack build --fast --nix

Or enable the option for nix building in your local configuration for Stack.

.. _cabal--nix:

Cabal + Nix

There is an option of using just Cabal + Nix as well - use a small
utility script (watch out, it's a dot before the ``cabal``!) and work as
you would usually if you develop with cabal:

::

   ./cabal new-build

Adding new dependencies can be easy with, for example:

::

   cabal2nix https://github.com/input-output-hk/cardano-prelude --revision "2d6624af423d0a5c7ced6f3ae465eaaeb4ec739e" > cardano-prelude.nix

Tools
-----

You can install multiple tools that can help you, there are configs for
these tools in the project repo:

::

   stack install hindent
   stack install stylish-haskell
   stack install hsimport
   stack install hdevtools

.. |Coverage Status| image:: https://coveralls.io/repos/github/input-output-hk/cardano-shell/badge.svg?branch=HEAD
   :target: https://coveralls.io/github/input-output-hk/cardano-shell?branch=HEAD
.. |"master" Build status| image:: https://badge.buildkite.com/5e4cd5ff2fd87975136914d037c409618deb4d8ed6579f8635.svg?branch=master
   :target: https://buildkite.com/input-output-hk/cardano-shell
.. |cardano-shell| image:: https://user-images.githubusercontent.com/6264437/47286557-70baf200-d5ef-11e8-8fe7-8584a9d6ae44.jpg
.. |cardano-shell-responsibilities| image:: https://user-images.githubusercontent.com/6264437/47286789-736a1700-d5f0-11e8-9056-514101b237f0.jpg
.. |cardano-shell-integration| image:: https://user-images.githubusercontent.com/6264437/47286815-88df4100-d5f0-11e8-92a7-c807b6d3b47a.jpg

Coverage
~~~~~~~~

You can generate a coverage report for the entire project like so:

::

   nix-build -A cardanoShellHaskellPackages.projectCoverageReport --arg config "{ haskellNix = { coverage = true; }; }"

or for each package like this:

::

   nix-build -A cardanoShellHaskellPackages.cardano-shell.coverageReport --arg config "{ haskellNix = { coverage = true; }; }"
   nix-build -A cardanoShellHaskellPackages.cardano-launcher.coverageReport --arg config "{ haskellNix = { coverage = true; }; }"

The CI is currently configured to upload a project coverage report to
a coverage web service. It does this using the script provided by:

::

   $(nix-build -A uploadCoverallsScript --arg config "{ haskellNix = { coverage = true; }; }")/bin/uploadCoveralls.sh