commit f31421576b00f0b167cdbe61217c31c21a41ac02 Author: Michael DeHaan Date: Thu Feb 23 14:17:24 2012 -0500 Genesis. diff --git a/README.md b/README.md new file mode 100644 index 0000000000..60bbc9f813 --- /dev/null +++ b/README.md @@ -0,0 +1,88 @@ +Ansible +======= + +Ansible is a extra-simple Python API for doing 'remote things' over SSH. + +As Func, which I co-wrote, aspired to avoid using SSH and have it's own daemon infrastructure, Ansible aspires to be quite different and more minimal, but still able to grow more modularly over time. + +Principles +========== + +* Dead simple setup +* No server or client daemons, uses existing SSHd +* Only SSH keys are allowed for authentication +* usage of ssh-agent is more or less required +* plugins can be written in ANY language +* as with Func, API usage is an equal citizen to CLI usage + +Requirements +============ + +* python 2.6 -- or a backport of the multiprocessing module +* paramiko + +Inventory file +============== + +The default inventory file (-H) is ~/.ansible_hosts and is a list +of all hostnames to target with ansible, one per line. + +This list is further filtered by the pattern wildcard (-P) to target +specific hosts. + +Comamnd line usage example +========================== + +Run a module by name with arguments + +ansible -p "*.example.com" -m modName -a "arg1 arg2" + +API Example +=========== + +The API is simple and returns basic datastructures. + +import ansible +runner = ansible.Runner(command='inventory', host_list=['xyz.example.com', '...']) +data = runner.run() + +{ + 'xyz.example.com' : [ 'any kind of datastructure is returnable' ], + 'foo.example.com' : None, # failed to connect, + ... +} + +Additional options to runner include the number of forks, hostname +exclusion pattern, library path, and so on. + +Parallelism +=========== + +Specify the number of forks to use, to run things in greater parallelism. + +ansible -f 10 "*.example.com" -m modName -a "arg1 arg2" + +Bundled Modules +=============== + +See the example library for modules, they can be written in any language +and simply return JSON to stdout. The path to your ansible library is +specified with the "-L" flag should you wish to use a different location +than "~/ansible". + +Features not supported from Func (by design) +============================================ + +* Delegation for treeish topologies +* Asynchronous modes for long running tasks -- background tasks on your own + +Future plans +============ + +* Dead-simple declarative configuration management & facts engine, with + probes implementable in any language. + +Author +====== + +* Michael DeHaan | http://michaeldehaan.net/ diff --git a/lib/ansible/__init__.py b/lib/ansible/__init__.py new file mode 100644 index 0000000000..d32d04cd1e --- /dev/null +++ b/lib/ansible/__init__.py @@ -0,0 +1,165 @@ +# core +from optparse import OptionParser +import fnmatch +from multiprocessing import Process, Pipe +from itertools import izip +import os +import json + +# non-core +import paramiko + +DEFAULT_HOST_LIST = '~/.ansible_hosts' +DEFAULT_MODULE_PATH = '~/ansible' +DEFAULT_MODULE_NAME = 'ping' +DEFAULT_PATTERN = '*' +DEFAULT_FORKS = 3 +DEFAULT_MODULE_ARGS = '' + +class Pooler(object): + + # credit: http://stackoverflow.com/questions/3288595/multiprocessing-using-pool-map-on-a-function-defined-in-a-class + + @classmethod + def spawn(cls, f): + def fun(pipe,x): + pipe.send(f(x)) + pipe.close() + return fun + + @classmethod + def parmap(cls, f, X): + pipe=[Pipe() for x in X] + proc=[Process(target=cls.spawn(f),args=(c,x)) for x,(p,c) in izip(X,pipe)] + [p.start() for p in proc] + [p.join() for p in proc] + return [p.recv() for (p,c) in pipe] + +class Cli(object): + + def __init__(self): + pass + + def runner(self): + parser = OptionParser() + parser.add_option("-H", "--host-list", dest="host_list", + help="path to hosts list", default=DEFAULT_HOST_LIST) + parser.add_option("-L", "--library", dest="module_path", + help="path to module library", default=DEFAULT_MODULE_PATH) + parser.add_option("-F", "--forks", dest="forks", + help="level of parallelism", default=DEFAULT_FORKS) + parser.add_option("-n", "--name", dest="module_name", + help="module name to execute", default=DEFAULT_MODULE_NAME) + parser.add_option("-a", "--args", dest="module_args", + help="module arguments", default=DEFAULT_MODULE_ARGS) + parser.add_option("-p", "--pattern", dest="pattern", + help="hostname pattern", default=DEFAULT_PATTERN) + + options, args = parser.parse_args() + host_list = self._host_list(options.host_list) + + return Runner( + module_name=options.module_name, + module_path=options.module_path, + module_args=options.module_args, + host_list=host_list, + forks=options.forks, + pattern=options.pattern, + ) + + def _host_list(self, host_list): + host_list = os.path.expanduser(host_list) + return file(host_list).read().split("\n") + + +class Runner(object): + + def __init__(self, host_list=[], module_path=None, + module_name=None, module_args='', + forks=3, timeout=60, pattern='*'): + + self.host_list = host_list + self.module_path = module_path + self.module_name = module_name + self.forks = forks + self.pattern = pattern + self.module_args = module_args + self.timeout = timeout + + + def _matches(self, host_name): + if host_name == '': + return False + if fnmatch.fnmatch(host_name, self.pattern): + return True + return False + + def _connect(self, host): + ssh = paramiko.SSHClient() + ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy()) + try: + ssh.connect(host, username='root', + allow_agent=True, look_for_keys=True) + return ssh + except: + return None + + def _executor(self, host): + # TODO: try/catch returning none + conn = self._connect(host) + if not conn: + return [ host, None ] + outpath = self._copy_module(conn) + self._exec_command(conn, "chmod +x %s" % outpath) + cmd = self._command(outpath) + result = self._exec_command(conn, cmd) + result = json.loads(result) + return [ host, result ] + + def _command(self, outpath): + cmd = "%s %s" % (outpath, self.module_args) + return cmd + + def _exec_command(self, conn, cmd): + stdin, stdout, stderr = conn.exec_command(cmd) + results = stdout.read() + return results + + def _copy_module(self, conn): + inpath = os.path.expanduser(os.path.join(self.module_path, self.module_name)) + outpath = os.path.join("/var/spool/", "ansible_%s" % self.module_name) + ftp = conn.open_sftp() + ftp.put(inpath, outpath) + ftp.close() + return outpath + + def run(self): + hosts = [ h for h in self.host_list if self._matches(h) ] + def executor(x): + return self._executor(x) + results = Pooler.parmap(executor, hosts) + by_host = dict(results) + return by_host + + +if __name__ == '__main__': + + # comamnd line usage example: + + result = Cli().runner().run() + print json.dumps(result, sort_keys=True, indent=4) + + # API usage example: + + #r = Runner( + # host_list = [ '127.0.0.1' ], + # module_path='~/.ansible', + # module_name='ping', + # module_args='', + # pattern='*', + # forks=3 + #) + #print r.run() + + +