Package: mirakuru
mirakuruMirakuru is a process orchestration tool designed for functional and integration tests.Maybe you want to be able to start a database before you start your program
or maybe you just need to set additional services up for your tests.
This is where you should consider usingmirakuruto add superpowers to your program or tests.UsageIn a project that relies on multiple processes there might be a need to guard code
with tests that verify interprocess communication. So one needs to set up all of
required databases, auxiliary and application services to verify their cooperation.
Synchronising (or orchestrating) test procedure with tested processes might be a hell.If so, thenmirakuruis what you need.Mirakurustarts your process and waits for the clear indication that it’s running.
Library provides seven executors to fit different cases:SimpleExecutor- starts a process and does not wait for anything.
It is useful to stop or kill a process and its subprocesses.
Base class for all the rest of executors.Executor- base class for executors verifying if a process has started.OutputExecutor- waits for a specified output to be printed by a process.TCPExecutor- waits for the ability to connect through TCP with a process.UnixSocketExecutor- waits for the ability to connect through Unix socket
with a processHTTPExecutor- waits for a successful HEAD request (and TCP before).PidExecutor- waits for a specified .pid file to exist.SimpleExecutorThe simplest executor implementation.
It simply starts the process passed to constructor, and reports it as running.frommirakuruimportSimpleExecutorprocess=SimpleExecutor('my_special_process')process.start()# Here you can do your stuff, e.g. communicate with the started processprocess.stop()OutputExecutorOutputExecutor is the executor that starts the process,
but does not report it as started, unless it receives specified marker/banner in
process output.frommirakuruimportOutputExecutorprocess=OutputExecutor('my_special_process',banner='processed!')process.start()# Here you can do your stuff, e.g. communicate with the started processprocess.stop()What happens during start here, is that the executor constantly checks output
produced by started process, and looks for the banner part occurring within the
output.
Once the output is identified, as in exampleprocessed!is found in output.
It is considered as started, and executor releases your script from wait to work.TCPExecutorIs the executor that should be used to start
processes that are using TCP connection. This executor tries to connect with
the process on given host:port to see if it started accepting connections. Once it
does, it reports the process as started and a code returns to normal execution.frommirakuruimportTCPExecutorprocess=TCPExecutor('my_special_process',host='localhost',port=1234)process.start()# Here you can do your stuff, e.g. communicate with the started processprocess.stop()HTTPExecutorIs executor that will be used to start web applications for example.
To start it, you apart from command, you need to pass a URL.
This URL will be used to make a (by default) HEAD request. Once successful,
the executor will be considered started, and a code will return to normal execution.frommirakuruimportHTTPExecutorprocess=HTTPExecutor('my_special_process',url='http://localhost:6543/status')process.start()# Here you can do your stuff, e.g. communicate with the started processprocess.stop()This executor, however, apart from HEAD request, also inherits TCPExecutor,
so it’ll try to connect to process over TCP first, to determine,
if it can try to make a HEAD request already.By default HTTPExecutor waits until its subprocess responds with 2XX HTTP status code.
If you consider other codes as valid you need to specify them in ‘status’ argument.frommirakuruimportHTTPExecutorprocess=HTTPExecutor('my_special_process',url='http://localhost:6543/status',status='(200|404)')process.start()The “status” argument can be a single code integer like 200, 404, 500 or a regular expression string -
‘^(2|4)00$’, ‘2dd’, ‘d{3}’, etc.There’s also a possibility to change the request method used to perform request to the server.
By default it’s HEAD, but GET, POST or other are also possible.frommirakuruimportHTTPExecutorprocess=HTTPExecutor('my_special_process',url='http://localhost:6543/status',status='(200|404)',method='GET')process.start()PidExecutorIs an executor that starts the given
process, and then waits for a given file to be found before it gives back control.
An example use for this class is writing integration tests for processes that
notify their running by creating a .pid file.frommirakuruimportPidExecutorprocess=PidExecutor('my_special_process',filename='/var/msp/my_special_process.pid')process.start()# Here you can do your stuff, e.g. communicate with the started processprocess.stop()frommirakuruimportHTTPExecutorfromhttplibimportHTTPConnection,OKdeftest_it_works():# The ``./http_server`` here launches some HTTP server on the 6543 port,# but naturally it is not immediate and takes a non-deterministic time:executor=HTTPExecutor("./http_server",url="http://127.0.0.1:6543/")# Start the server and wait for it to run (blocking):executor.start()# Here the server should be running!conn=HTTPConnection("127.0.0.1",6543)conn.request("GET","/")assertconn.getresponse().statusisOKexecutor.stop()A command by which executor spawns a process can be defined by either string or list.# command as stringTCPExecutor('python -m smtpd -n -c DebuggingServer localhost:1025',host='localhost',port=1025)# command as listTCPExecutor(['python','-m','smtpd','-n','-c','DebuggingServer','localhost:1025'],host='localhost',port=1025)Use as a Context managerStartingMirakuru executors can also work as a context managers.frommirakuruimportHTTPExecutorwithHTTPExecutor('my_special_process',url='http://localhost:6543/status')asprocess:# Here you can do your stuff, e.g. communicate with the started processassertprocess.running()isTrueassertprocess.running()isFalseDefined process starts upon entering context, and exit upon exiting it.StoppingMirakuru also allows to stop process for given context.
To do this, simply use built-in stopped context manager.frommirakuruimportHTTPExecutorprocess=HTTPExecutor('my_special_process',url='http://localhost:6543/status').start()# Here you can do your stuff, e.g. communicate with the started processwithprocess.stopped():# Here you will not be able to communicate with the process as it is killed hereassertprocess.running()isFalseassertprocess.running()isTrueDefined process stops upon entering context, and starts upon exiting it.Methods chainingMirakuru encourages methods chaining so you can inline some operations, e.g.:frommirakuruimportSimpleExecutorcommand_stdout=SimpleExecutor('my_special_process').start().stop().outputContributing and reporting bugsSource code is available at:ClearcodeHQ/mirakuru.
Issue tracker is located atGitHub Issues.
ProjectsPyPI page.Windows supportFrankly, there’s none, Python’s support differs a bit in required places
and the team has no experience in developing for Windows.
However we’d welcome contributions that will allow the windows support.See:#392#336Also, With the introduction ofWSLthe need for raw Windows support might not be that urgant… If you’ve got any thoughts or are willing to contribute,
please start with the issues listed above.ReleaseInstall pipenv and –dev dependencies first, Then run:pipenv run tbump [NEW_VERSION]