Chirp

Message-passing and actor-based programming for everyone

It is part of Concreteclouds and the C99 implementation of pychirp.

[1] [2]

Read the Docs

[1]	Python/hypothesis based test-suite in external project seecc.

[2]	Coverage enforced by tests (on travis, after 1.0 release)

WORK IN PROGRESS

Features

• Fully automatic connection setup
• TLS support
  • Connections to 127.0.0.1 and ::1 aren't encrypted
  • We support and test with OpenSSL, but we prefer LibreSSL
• Flow control
  • Chirp won't overload peers out-of-the box, if you work with long requests >2.5s adjust the timeout
  • Peer-load is reported so you can implement load-balancing easily
• Easy message routing
• Robust
  • No message can be lost without an error (or it is a bug)
  • Due to retry it takes a very bad network for messages to be lost
• Very thin API
• Minimal code-base, all additional features will be implemented as modules in an upper layer
• Fast
  • Up to 50'000 msg/s on a single-connection (encrypted 35'000 msg/s)
  • Up to 100'000 msg/s in star-topology (encrypted same)
    • Which shows that chirp is highly optimized, but still if the network delay is bigger star-topology is the way to go.

Install

Unix

Build dependencies:

• python3 [3]
• make
• gcc or clang

Documentation build dependencies:

• sphinx
• graphviz

Dependencies:

• libuv
• openssl

Install to prefix /usr/local. (with docs)

cd build
../configure --doc
make
make check
sudo make install

Install to prefix /usr. (without docs)

cd build
../configure --prefix /usr
make
make check
sudo make install

In-source build is also possible.

./configure
make
make check
sudo make install

[3]	Script-headers can be patched to work with python2. It also possible to generate the makefile on a different system (for example in a embedded scenario)

Windows

• Install Visual Studio 2015 if you want to build for python 3
  • Select Git for Windows in Visual Studio Installer or install it
• Install Visual Studio 2008 Express
• Install Windows SDK for Windows Server 2008 and .NET Framework 3.5 (python 2)

Note

To support python 2.7 == Visual Studio 2008, we use c99conv to convert to c89 and we support python 3.5+ == Visual Studio 2015 without c99conv. Any future version of python that uses a newer version of Visual Studio has to added to the build-system explicitly.

python configure
make.cmd

Development

Test dependencies:

• cppcheck
• abi-compliance-checker

Unix

cd build
../configure --dev
make test

In development mode the make file has a help:

make

Please memcheck your code, we haven't automated memcheck, yet:

valgrind --tool=memcheck ./src/[relevant]_etest

Chirp has a mode to debug macros:

../configure --dev
make clean all MACRO_DEBUG=True
gdb src/structures_etest

This requires clang-format to be installed.

Docker

If a tool is not available on your platform or you have a old version of cppcheck (cppcheck is known to behave very different across versions), you can use the docker based tests.

./ci/alpine.sh

Travis will also run this script, so you can also use it to reproduce errors on travis.

You can also run a shell.

./ci/alpine.sh shell

./ci/arch.sh shell

Windows

No development build available.

Check vs test

make check

Not instrumented (release mode), goal: checking compatibility

make test

Instrumented (dev mode), goal: helping developers to find bugs

Syntastic

By default vim will treat *.h files as cpp, but syntastic has no make-checker for cpp, so *.h would not get checked.

let g:syntastic_c_checkers = ['make']
au BufNewFile,BufRead *.h set ft=c

With this setting syntastic will check the following:

• Clang-based build errors
• Line length
• Trailing whitespaces

Clang complete

If you use clang complete, we recommend

let g:clang_auto_select     = 1
let g:clang_snippets        = 1
let g:clang_snippets_engine = 'clang_complete'

License

LGPL 3.0

Contribution

1. Ask first
2. You must sign-over the changes to the Concrete Clouds Project
3. So you usually just want to open change-requests