client/common_lib/test.py

# Shell class for a test, inherited by all individual tests
#
# Methods:
#       __init__        initialise
#       initialize      run once for each job
#       setup           run once for each new version of the test installed
#       run             run the test (wrapped by job.run_test())
#
# Data:
#       job             backreference to the job this test instance is part of
#       outputdir       eg. results/<job>/<testname.tag>
#       resultsdir      eg. results/<job>/<testname.tag>/results
#       profdir         eg. results/<job>/<testname.tag>/profiling
#       debugdir        eg. results/<job>/<testname.tag>/debug
#       bindir          eg. tests/<test>
#       src             eg. tests/<test>/src
#       tmpdir          eg. tmp/<tempname>_<testname.tag>

import fcntl, os, re, sys, shutil, tarfile, tempfile, time, traceback
import warnings, logging, glob, resource

from autotest_lib.client.common_lib import error
from autotest_lib.client.bin import utils


class base_test:
    preserve_srcdir = False
    network_destabilizing = False

    def __init__(self, job, bindir, outputdir):
        self.job = job
        self.pkgmgr = job.pkgmgr
        self.autodir = job.autodir
        self.outputdir = outputdir
        self.tagged_testname = os.path.basename(self.outputdir)
        self.resultsdir = os.path.join(self.outputdir, 'results')
        os.mkdir(self.resultsdir)
        self.profdir = os.path.join(self.outputdir, 'profiling')
        os.mkdir(self.profdir)
        self.debugdir = os.path.join(self.outputdir, 'debug')
        os.mkdir(self.debugdir)
        self.configure_crash_handler()
        self.bindir = bindir
        if hasattr(job, 'libdir'):
            self.libdir = job.libdir
        self.srcdir = os.path.join(self.bindir, 'src')
        self.tmpdir = tempfile.mkdtemp("_" + self.tagged_testname,
                                       dir=job.tmpdir)
        self._keyvals = []
        self._new_keyval = False
        self.failed_constraints = []
        self.iteration = 0
        self.before_iteration_hooks = []
        self.after_iteration_hooks = []


    def configure_crash_handler(self):
        """
        Configure the crash handler by:
         * Setting up core size to unlimited
         * Putting an appropriate crash handler on /proc/sys/kernel/core_pattern
         * Create files that the crash handler will use to figure which tests
           are active at a given moment

        The crash handler will pick up the core file and write it to
        self.debugdir, and perform analysis on it to generate a report. The
        program also outputs some results to syslog.

        If multiple tests are running, an attempt to verify if we still have
        the old PID on the system process table to determine whether it is a
        parent of the current test execution. If we can't determine it, the
        core file and the report file will be copied to all test debug dirs.
        """
        self.pattern_file = '/proc/sys/kernel/core_pattern'
        try:
            # Enable core dumps
            resource.setrlimit(resource.RLIMIT_CORE, (-1, -1))
            # Trying to backup core pattern and register our script
            self.core_pattern_backup = open(self.pattern_file, 'r').read()
            pattern_file = open(self.pattern_file, 'w')
            tools_dir = os.path.join(self.autodir, 'tools')
            crash_handler_path = os.path.join(tools_dir, 'crash_handler.py')
            pattern_file.write('|' + crash_handler_path + ' %p %t %u %s %h %e')
            # Writing the files that the crash handler is going to use
            self.debugdir_tmp_file = ('/tmp/autotest_results_dir.%s' %
                                      os.getpid())
            utils.open_write_close(self.debugdir_tmp_file, self.debugdir + "\n")
        except Exception, e:
            self.crash_handling_enabled = False
            logging.error('Crash handling system disabled: %s' % e)
        else:
            self.crash_handling_enabled = True
            logging.debug('Crash handling system enabled.')


    def crash_handler_report(self):
        """
        If core dumps are found on the debugdir after the execution of the
        test, let the user know.
        """
        if self.crash_handling_enabled:
            core_dirs = glob.glob('%s/crash.*' % self.debugdir)
            if core_dirs:
                logging.warning('Programs crashed during test execution:')
                for dir in core_dirs:
                    logging.warning('Please verify %s for more info', dir)
            # Remove the debugdir info file
            os.unlink(self.debugdir_tmp_file)
            # Restore the core pattern backup
            try:
                utils.open_write_close(self.pattern_file,
                                       self.core_pattern_backup)
            except EnvironmentError:
                pass


    def assert_(self, expr, msg='Assertion failed.'):
        if not expr:
            raise error.TestError(msg)


    def write_test_keyval(self, attr_dict):
        utils.write_keyval(self.outputdir, attr_dict)


    @staticmethod
    def _append_type_to_keys(dictionary, typename):
        new_dict = {}
        for key, value in dictionary.iteritems():
            new_key = "%s{%s}" % (key, typename)
            new_dict[new_key] = value
        return new_dict


    def write_perf_keyval(self, perf_dict):
        self.write_iteration_keyval({}, perf_dict)


    def write_attr_keyval(self, attr_dict):
        self.write_iteration_keyval(attr_dict, {})


    def write_iteration_keyval(self, attr_dict, perf_dict):
        # append the dictionaries before they have the {perf} and {attr} added
        self._keyvals.append({'attr':attr_dict, 'perf':perf_dict})
        self._new_keyval = True

        if attr_dict:
            attr_dict = self._append_type_to_keys(attr_dict, "attr")
            utils.write_keyval(self.resultsdir, attr_dict, type_tag="attr")

        if perf_dict:
            perf_dict = self._append_type_to_keys(perf_dict, "perf")
            utils.write_keyval(self.resultsdir, perf_dict, type_tag="perf")

        keyval_path = os.path.join(self.resultsdir, "keyval")
        print >> open(keyval_path, "a"), ""


    def analyze_perf_constraints(self, constraints):
        if not self._new_keyval:
            return

        # create a dict from the keyvals suitable as an environment for eval
        keyval_env = self._keyvals[-1]['perf'].copy()
        keyval_env['__builtins__'] = None
        self._new_keyval = False
        failures = []

        # evaluate each constraint using the current keyvals
        for constraint in constraints:
            logging.info('___________________ constraint = %s', constraint)
            logging.info('___________________ keyvals = %s', keyval_env)

            try:
                if not eval(constraint, keyval_env):
                    failures.append('%s: constraint was not met' % constraint)
            except:
                failures.append('could not evaluate constraint: %s'
                                % constraint)

        # keep track of the errors for each iteration
        self.failed_constraints.append(failures)


    def process_failed_constraints(self):
        msg = ''
        for i, failures in enumerate(self.failed_constraints):
            if failures:
                msg += 'iteration %d:%s  ' % (i, ','.join(failures))

        if msg:
            raise error.TestFail(msg)


    def register_before_iteration_hook(self, iteration_hook):
        """
        This is how we expect test writers to register a before_iteration_hook.
        This adds the method to the list of hooks which are executed
        before each iteration.

        @param iteration_hook: Method to run before each iteration. A valid
                               hook accepts a single argument which is the
                               test object.
        """
        self.before_iteration_hooks.append(iteration_hook)


    def register_after_iteration_hook(self, iteration_hook):
        """
        This is how we expect test writers to register an after_iteration_hook.
        This adds the method to the list of hooks which are executed
        after each iteration.

        @param iteration_hook: Method to run after each iteration. A valid
                               hook accepts a single argument which is the
                               test object.
        """
        self.after_iteration_hooks.append(iteration_hook)


    def initialize(self):
        pass


    def setup(self):
        pass


    def warmup(self, *args, **dargs):
        pass


    def drop_caches_between_iterations(self):
        if self.job.drop_caches_between_iterations:
            print "Dropping caches between iterations"
            utils.drop_caches()


    def _call_run_once(self, constraints, profile_only,
                       postprocess_profiled_run, args, dargs):
        self.drop_caches_between_iterations()

        # execute iteration hooks
        for hook in self.before_iteration_hooks:
            hook(self)

        if profile_only:
            if not self.job.profilers.present():
                self.job.record('WARN', None, None, 'No profilers have been '
                                'added but profile_only is set - nothing '
                                'will be run')
            self.run_once_profiling(postprocess_profiled_run, *args, **dargs)
        else:
            self.run_once(*args, **dargs)

        for hook in self.after_iteration_hooks:
            hook(self)

        self.postprocess_iteration()
        self.analyze_perf_constraints(constraints)


    def execute(self, iterations=None, test_length=None, profile_only=False,
                _get_time=time.time, postprocess_profiled_run=None,
                constraints=(), *args, **dargs):
        """
        This is the basic execute method for the tests inherited from base_test.
        If you want to implement a benchmark test, it's better to implement
        the run_once function, to cope with the profiling infrastructure. For
        other tests, you can just override the default implementation.

        @param test_length: The minimum test length in seconds. We'll run the
            run_once function for a number of times large enough to cover the
            minimum test length.

        @param iterations: A number of iterations that we'll run the run_once
            function. This parameter is incompatible with test_length and will
            be silently ignored if you specify both.

        @param profile_only: If true run X iterations with profilers enabled.
            Otherwise run X iterations and one with profiling if profiles are
            enabled.

        @param _get_time: [time.time] Used for unit test time injection.

        @param postprocess_profiled_run: Run the postprocessing for the
            profiled run.
        """

        # For our special class of tests, the benchmarks, we don't want
        # profilers to run during the test iterations. Let's reserve only
        # the last iteration for profiling, if needed. So let's stop
        # all profilers if they are present and active.
        profilers = self.job.profilers
        if profilers.active():
            profilers.stop(self)
        # If the user called this test in an odd way (specified both iterations
        # and test_length), let's warn them.
        if iterations and test_length:
            logging.info('Iterations parameter ignored (timed execution).')
        if test_length:
            test_start = _get_time()
            time_elapsed = 0
            timed_counter = 0
            logging.info('Test started. Minimum test length: %d s',
                               test_length)
            while time_elapsed < test_length:
                timed_counter = timed_counter + 1
                if time_elapsed == 0:
                    logging.info('Executing iteration %d', timed_counter)
                elif time_elapsed > 0:
                    logging.info(
                            'Executing iteration %d, time_elapsed %d s',
                            timed_counter, time_elapsed)
                self._call_run_once(constraints, profile_only,
                                    postprocess_profiled_run, args, dargs)
                test_iteration_finish = _get_time()
                time_elapsed = test_iteration_finish - test_start
            logging.info('Test finished after %d iterations',
                               timed_counter)
            logging.info('Time elapsed: %d s', time_elapsed)
        else:
            if iterations is None:
                iterations = 1
            logging.info('Test started. Number of iterations: %d', iterations)
            for self.iteration in xrange(1, iterations+1):
                logging.info('Executing iteration %d of %d', self.iteration,
                                                             iterations)
                self._call_run_once(constraints, profile_only,
                                    postprocess_profiled_run, args, dargs)
            logging.info('Test finished after %d iterations.', iterations)

        if not profile_only:
            self.iteration += 1
            self.run_once_profiling(postprocess_profiled_run, *args, **dargs)

        # Do any postprocessing, normally extracting performance keyvals, etc
        self.postprocess()
        self.process_failed_constraints()


    def run_once_profiling(self, postprocess_profiled_run, *args, **dargs):
        profilers = self.job.profilers
        # Do a profiling run if necessary
        if profilers.present():
            self.drop_caches_between_iterations()
            profilers.start(self)
            print 'Profilers present. Profiling run started'
            try:
                self.run_once(*args, **dargs)

                # Priority to the run_once() argument over the attribute.
                postprocess_attribute = getattr(self,
                                                'postprocess_profiled_run',
                                                False)

                if (postprocess_profiled_run or
                    (postprocess_profiled_run is None and
                     postprocess_attribute)):
                    self.postprocess_iteration()

            finally:
                profilers.stop(self)
                profilers.report(self)


    def postprocess(self):
        pass


    def postprocess_iteration(self):
        pass


    def cleanup(self):
        pass


    def _exec(self, args, dargs):
        self.job.logging.tee_redirect_debug_dir(self.debugdir,
                                                log_name=self.tagged_testname)
        try:
            if self.network_destabilizing:
                self.job.disable_warnings("NETWORK")

            # write out the test attributes into a keyval
            dargs   = dargs.copy()
            run_cleanup = dargs.pop('run_cleanup', self.job.run_test_cleanup)
            keyvals = dargs.pop('test_attributes', {}).copy()
            keyvals['version'] = self.version
            for i, arg in enumerate(args):
                keyvals['param-%d' % i] = repr(arg)
            for name, arg in dargs.iteritems():
                keyvals['param-%s' % name] = repr(arg)
            self.write_test_keyval(keyvals)

            _validate_args(args, dargs, self.initialize, self.setup,
                           self.execute, self.cleanup)

            try:
                # Initialize:
                _cherry_pick_call(self.initialize, *args, **dargs)

                lockfile = open(os.path.join(self.job.tmpdir, '.testlock'), 'w')
                try:
                    fcntl.flock(lockfile, fcntl.LOCK_EX)
                    # Setup: (compile and install the test, if needed)
                    p_args, p_dargs = _cherry_pick_args(self.setup,args,dargs)
                    utils.update_version(self.srcdir, self.preserve_srcdir,
                                         self.version, self.setup,
                                         *p_args, **p_dargs)
                finally:
                    fcntl.flock(lockfile, fcntl.LOCK_UN)
                    lockfile.close()

                # Execute:
                os.chdir(self.outputdir)

                # call self.warmup cherry picking the arguments it accepts and
                # translate exceptions if needed
                _call_test_function(_cherry_pick_call, self.warmup,
                                    *args, **dargs)

                if hasattr(self, 'run_once'):
                    p_args, p_dargs = _cherry_pick_args(self.run_once,
                                                        args, dargs)
                    # pull in any non-* and non-** args from self.execute
                    for param in _get_nonstar_args(self.execute):
                        if param in dargs:
                            p_dargs[param] = dargs[param]
                else:
                    p_args, p_dargs = _cherry_pick_args(self.execute,
                                                        args, dargs)

                _call_test_function(self.execute, *p_args, **p_dargs)
            except Exception:
                # Save the exception while we run our cleanup() before
                # reraising it.
                exc_info = sys.exc_info()
                try:
                    try:
                        if run_cleanup:
                            _cherry_pick_call(self.cleanup, *args, **dargs)
                    except Exception:
                        print 'Ignoring exception during cleanup() phase:'
                        traceback.print_exc()
                        print 'Now raising the earlier %s error' % exc_info[0]
                    self.crash_handler_report()
                finally:
                    self.job.logging.restore()
                    try:
                        raise exc_info[0], exc_info[1], exc_info[2]
                    finally:
                        # http://docs.python.org/library/sys.html#sys.exc_info
                        # Be nice and prevent a circular reference.
                        del exc_info
            else:
                try:
                    if run_cleanup:
                        _cherry_pick_call(self.cleanup, *args, **dargs)
                    self.crash_handler_report()
                finally:
                    self.job.logging.restore()
        except error.AutotestError:
            if self.network_destabilizing:
                self.job.enable_warnings("NETWORK")
            # Pass already-categorized errors on up.
            raise
        except Exception, e:
            if self.network_destabilizing:
                self.job.enable_warnings("NETWORK")
            # Anything else is an ERROR in our own code, not execute().
            raise error.UnhandledTestError(e)
        else:
            if self.network_destabilizing:
                self.job.enable_warnings("NETWORK")


def _get_nonstar_args(func):
    """Extract all the (normal) function parameter names.

    Given a function, returns a tuple of parameter names, specifically
    excluding the * and ** parameters, if the function accepts them.

    @param func: A callable that we want to chose arguments for.

    @return: A tuple of parameters accepted by the function.
    """
    return func.func_code.co_varnames[:func.func_code.co_argcount]


def _cherry_pick_args(func, args, dargs):
    """Sanitize positional and keyword arguments before calling a function.

    Given a callable (func), an argument tuple and a dictionary of keyword
    arguments, pick only those arguments which the function is prepared to
    accept and return a new argument tuple and keyword argument dictionary.

    Args:
      func: A callable that we want to choose arguments for.
      args: A tuple of positional arguments to consider passing to func.
      dargs: A dictionary of keyword arguments to consider passing to func.
    Returns:
      A tuple of: (args tuple, keyword arguments dictionary)
    """
    # Cherry pick args:
    if func.func_code.co_flags & 0x04:
        # func accepts *args, so return the entire args.
        p_args = args
    else:
        p_args = ()

    # Cherry pick dargs:
    if func.func_code.co_flags & 0x08:
        # func accepts **dargs, so return the entire dargs.
        p_dargs = dargs
    else:
        # Only return the keyword arguments that func accepts.
        p_dargs = {}
        for param in _get_nonstar_args(func):
            if param in dargs:
                p_dargs[param] = dargs[param]

    return p_args, p_dargs


def _cherry_pick_call(func, *args, **dargs):
    """Cherry picks arguments from args/dargs based on what "func" accepts
    and calls the function with the picked arguments."""
    p_args, p_dargs = _cherry_pick_args(func, args, dargs)
    return func(*p_args, **p_dargs)


def _validate_args(args, dargs, *funcs):
    """Verify that arguments are appropriate for at least one callable.

    Given a list of callables as additional parameters, verify that
    the proposed keyword arguments in dargs will each be accepted by at least
    one of the callables.

    NOTE: args is currently not supported and must be empty.

    Args:
      args: A tuple of proposed positional arguments.
      dargs: A dictionary of proposed keyword arguments.
      *funcs: Callables to be searched for acceptance of args and dargs.
    Raises:
      error.AutotestError: if an arg won't be accepted by any of *funcs.
    """
    all_co_flags = 0
    all_varnames = ()
    for func in funcs:
        all_co_flags |= func.func_code.co_flags
        all_varnames += func.func_code.co_varnames[:func.func_code.co_argcount]

    # Check if given args belongs to at least one of the methods below.
    if len(args) > 0:
        # Current implementation doesn't allow the use of args.
        raise error.TestError('Unnamed arguments not accepted. Please '
                              'call job.run_test with named args only')

    # Check if given dargs belongs to at least one of the methods below.
    if len(dargs) > 0:
        if not all_co_flags & 0x08:
            # no func accepts *dargs, so:
            for param in dargs:
                if not param in all_varnames:
                    raise error.AutotestError('Unknown parameter: %s' % param)


def _installtest(job, url):
    (group, name) = job.pkgmgr.get_package_name(url, 'test')

    # Bail if the test is already installed
    group_dir = os.path.join(job.testdir, "download", group)
    if os.path.exists(os.path.join(group_dir, name)):
        return (group, name)

    # If the group directory is missing create it and add
    # an empty  __init__.py so that sub-directories are
    # considered for import.
    if not os.path.exists(group_dir):
        os.mkdir(group_dir)
        f = file(os.path.join(group_dir, '__init__.py'), 'w+')
        f.close()

    print name + ": installing test url=" + url
    tarball = os.path.basename(url)
    tarball_path = os.path.join(group_dir, tarball)
    test_dir = os.path.join(group_dir, name)
    job.pkgmgr.fetch_pkg(tarball, tarball_path,
                         repo_url = os.path.dirname(url))

    # Create the directory for the test
    if not os.path.exists(test_dir):
        os.mkdir(os.path.join(group_dir, name))

    job.pkgmgr.untar_pkg(tarball_path, test_dir)

    os.remove(tarball_path)

    # For this 'sub-object' to be importable via the name
    # 'group.name' we need to provide an __init__.py,
    # so link the main entry point to this.
    os.symlink(name + '.py', os.path.join(group_dir, name,
                            '__init__.py'))

    # The test is now installed.
    return (group, name)


def _call_test_function(func, *args, **dargs):
    """Calls a test function and translates exceptions so that errors
    inside test code are considered test failures."""
    try:
        return func(*args, **dargs)
    except error.AutotestError:
        # Pass already-categorized errors on up as is.
        raise
    except Exception, e:
        # Other exceptions must be treated as a FAIL when
        # raised during the test functions
        raise error.UnhandledTestFail(e)


def runtest(job, url, tag, args, dargs,
            local_namespace={}, global_namespace={},
            before_test_hook=None, after_test_hook=None,
            before_iteration_hook=None, after_iteration_hook=None):
    local_namespace = local_namespace.copy()
    global_namespace = global_namespace.copy()

    # if this is not a plain test name then download and install the
    # specified test
    if url.endswith('.tar.bz2'):
        (group, testname) = _installtest(job, url)
        bindir = os.path.join(job.testdir, 'download', group, testname)
        site_bindir = None
    else:
        # if the test is local, it can be found in either testdir
        # or site_testdir. tests in site_testdir override tests
        # defined in testdir
        (group, testname) = ('', url)
        bindir = os.path.join(job.testdir, group, testname)
        if hasattr(job, 'site_testdir'):
            site_bindir = os.path.join(job.site_testdir,
                                       group, testname)
        else:
            site_bindir = None

        # The job object here can be that of a server side job or a client
        # side job. 'install_pkg' method won't be present for server side
        # jobs, so do the fetch only if that method is present in the job
        # obj.
        if hasattr(job, 'install_pkg'):
            try:
                job.install_pkg(testname, 'test', bindir)
            except error.PackageInstallError, e:
                # continue as a fall back mechanism and see if the test code
                # already exists on the machine
                pass

    outputdir = os.path.join(job.resultdir, testname)
    if tag:
        outputdir += '.' + tag

    # if we can find the test in site_bindir, use this version
    if site_bindir and os.path.exists(site_bindir):
        bindir = site_bindir
        testdir = job.site_testdir
    elif os.path.exists(bindir):
        testdir = job.testdir
    else:
        raise error.TestError(testname + ': test does not exist')

    local_namespace['job'] = job
    local_namespace['bindir'] = bindir
    local_namespace['outputdir'] = outputdir

    if group:
        sys.path.insert(0, os.path.join(testdir, 'download'))
        group += '.'
    else:
        sys.path.insert(0, os.path.join(testdir, testname))

    try:
        exec ("import %s%s" % (group, testname),
              local_namespace, global_namespace)
        exec ("mytest = %s%s.%s(job, bindir, outputdir)" %
              (group, testname, testname),
              local_namespace, global_namespace)
    finally:
        sys.path.pop(0)

    pwd = os.getcwd()
    os.chdir(outputdir)

    try:
        mytest = global_namespace['mytest']
        if before_test_hook:
            before_test_hook(mytest)

        # we use the register iteration hooks methods to register the passed
        # in hooks
        if before_iteration_hook:
            mytest.register_before_iteration_hook(before_iteration_hook)
        if after_iteration_hook:
            mytest.register_after_iteration_hook(after_iteration_hook)
        mytest._exec(args, dargs)
    finally:
        os.chdir(pwd)
        if after_test_hook:
            after_test_hook(mytest)
        shutil.rmtree(mytest.tmpdir, ignore_errors=True)