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from __future__ import absolute_import 

from __future__ import division 

from __future__ import print_function 

from __future__ import unicode_literals 

 

from builtins import str, input, object 

from past.builtins import basestring 

from copy import copy 

from datetime import datetime, date, timedelta 

from dateutil.relativedelta import relativedelta  # for doctest 

from email.mime.text import MIMEText 

from email.mime.multipart import MIMEMultipart 

from email.mime.application import MIMEApplication 

import errno 

from functools import wraps 

import imp 

import inspect 

import json 

import logging 

import os 

import re 

import shutil 

import signal 

import six 

import smtplib 

from tempfile import mkdtemp 

 

from alembic.config import Config 

from alembic import command 

from alembic.migration import MigrationContext 

 

from contextlib import contextmanager 

 

from sqlalchemy import event, exc 

from sqlalchemy.pool import Pool 

 

import numpy as np 

from croniter import croniter 

 

from airflow import settings 

from airflow import configuration 

 

 

class AirflowException(Exception): 

    pass 

 

 

class AirflowSensorTimeout(Exception): 

    pass 

 

 

class TriggerRule(object): 

    ALL_SUCCESS = 'all_success' 

    ALL_FAILED = 'all_failed' 

    ALL_DONE = 'all_done' 

    ONE_SUCCESS = 'one_success' 

    ONE_FAILED = 'one_failed' 

    DUMMY = 'dummy' 

 

 

class State(object): 

    """ 

    Static class with task instance states constants and color method to 

    avoid hardcoding. 

    """ 

    QUEUED = "queued" 

    RUNNING = "running" 

    SUCCESS = "success" 

    SHUTDOWN = "shutdown"  # External request to shut down 

    FAILED = "failed" 

    UP_FOR_RETRY = "up_for_retry" 

    UPSTREAM_FAILED = "upstream_failed" 

    SKIPPED = "skipped" 

 

    state_color = { 

        QUEUED: 'gray', 

        RUNNING: 'lime', 

        SUCCESS: 'green', 

        SHUTDOWN: 'blue', 

        FAILED: 'red', 

        UP_FOR_RETRY: 'gold', 

        UPSTREAM_FAILED: 'orange', 

        SKIPPED: 'pink', 

    } 

 

    @classmethod 

    def color(cls, state): 

        if state in cls.state_color: 

            return cls.state_color[state] 

        else: 

            return 'white' 

 

    @classmethod 

    def runnable(cls): 

        return [ 

            None, cls.FAILED, cls.UP_FOR_RETRY, cls.UPSTREAM_FAILED, 

            cls.SKIPPED] 

 

 

cron_presets = { 

    '@hourly': '0 * * * *', 

    '@daily': '0 0 * * *', 

    '@weekly': '0 0 * * 0', 

    '@monthly': '0 0 1 * *', 

    '@yearly': '0 0 1 1 *', 

} 

 

def provide_session(func): 

    """ 

    Function decorator that provides a session if it isn't provided. 

    If you want to reuse a session or run the function as part of a 

    database transaction, you pass it to the function, if not this wrapper 

    will create one and close it for you. 

    """ 

    @wraps(func) 

    def wrapper(*args, **kwargs): 

        needs_session = False 

        if 'session' not in kwargs: 

            needs_session = True 

            session = settings.Session() 

            kwargs['session'] = session 

        result = func(*args, **kwargs) 

        if needs_session: 

            session.expunge_all() 

            session.commit() 

            session.close() 

        return result 

    return wrapper 

 

 

def pessimistic_connection_handling(): 

    @event.listens_for(Pool, "checkout") 

    def ping_connection(dbapi_connection, connection_record, connection_proxy): 

        ''' 

        Disconnect Handling - Pessimistic, taken from: 

        http://docs.sqlalchemy.org/en/rel_0_9/core/pooling.html 

        ''' 

        cursor = dbapi_connection.cursor() 

        try: 

            cursor.execute("SELECT 1") 

        except: 

            raise exc.DisconnectionError() 

        cursor.close() 

 

@provide_session 

def merge_conn(conn, session=None): 

    from airflow import models 

    C = models.Connection 

    if not session.query(C).filter(C.conn_id == conn.conn_id).first(): 

        session.add(conn) 

        session.commit() 

 

 

def initdb(): 

    session = settings.Session() 

    from airflow import models 

    upgradedb() 

 

    merge_conn( 

        models.Connection( 

            conn_id='airflow_db', conn_type='mysql', 

            host='localhost', login='root', password='', 

            schema='airflow')) 

    merge_conn( 

        models.Connection( 

            conn_id='beeline_default', conn_type='beeline', 

            host='localhost', 

            schema='airflow')) 

    merge_conn( 

        models.Connection( 

            conn_id='local_mysql', conn_type='mysql', 

            host='localhost', login='airflow', password='airflow', 

            schema='airflow')) 

    merge_conn( 

        models.Connection( 

            conn_id='presto_default', conn_type='presto', 

            host='localhost', 

            schema='hive', port=3400)) 

    merge_conn( 

        models.Connection( 

            conn_id='hive_cli_default', conn_type='hive_cli', 

            schema='default',)) 

    merge_conn( 

        models.Connection( 

            conn_id='hiveserver2_default', conn_type='hiveserver2', 

            host='localhost', 

            schema='default', port=10000)) 

    merge_conn( 

        models.Connection( 

            conn_id='metastore_default', conn_type='hive_metastore', 

            host='localhost', 

            port=10001)) 

    merge_conn( 

        models.Connection( 

            conn_id='mysql_default', conn_type='mysql', 

            login='root', 

            host='localhost')) 

    merge_conn( 

        models.Connection( 

            conn_id='postgres_default', conn_type='postgres', 

            login='postgres', 

            schema='airflow', 

            host='localhost')) 

    merge_conn( 

        models.Connection( 

            conn_id='sqlite_default', conn_type='sqlite', 

            host='/tmp/sqlite_default.db')) 

    merge_conn( 

        models.Connection( 

            conn_id='http_default', conn_type='http', 

            host='https://www.google.com/')) 

    merge_conn( 

        models.Connection( 

            conn_id='mssql_default', conn_type='mssql', 

            host='localhost', port=1433)) 

    merge_conn( 

        models.Connection( 

            conn_id='vertica_default', conn_type='vertica', 

            host='localhost', port=5433)) 

    merge_conn( 

        models.Connection( 

            conn_id='webhdfs_default', conn_type='hdfs', 

            host='localhost', port=50070)) 

 

    # Known event types 

    KET = models.KnownEventType 

    if not session.query(KET).filter(KET.know_event_type == 'Holiday').first(): 

        session.add(KET(know_event_type='Holiday')) 

    if not session.query(KET).filter(KET.know_event_type == 'Outage').first(): 

        session.add(KET(know_event_type='Outage')) 

    if not session.query(KET).filter( 

            KET.know_event_type == 'Natural Disaster').first(): 

        session.add(KET(know_event_type='Natural Disaster')) 

    if not session.query(KET).filter( 

            KET.know_event_type == 'Marketing Campaign').first(): 

        session.add(KET(know_event_type='Marketing Campaign')) 

    session.commit() 

 

    models.DagBag(sync_to_db=True) 

 

    Chart = models.Chart 

    chart_label = "Airflow task instance by type" 

    chart = session.query(Chart).filter(Chart.label == chart_label).first() 

    if not chart: 

        chart = Chart( 

            label=chart_label, 

            conn_id='airflow_db', 

            chart_type='bar', 

            x_is_date=False, 

            sql=( 

                "SELECT state, COUNT(1) as number " 

                "FROM task_instance " 

                "WHERE dag_id LIKE 'example%' " 

                "GROUP BY state"), 

        ) 

        session.add(chart) 

 

 

def upgradedb(): 

    logging.info("Creating tables") 

    package_dir = os.path.abspath(os.path.dirname(__file__)) 

    directory = os.path.join(package_dir, 'migrations') 

    config = Config(os.path.join(package_dir, 'alembic.ini')) 

    config.set_main_option('script_location', directory) 

    config.set_main_option('sqlalchemy.url', 

                           configuration.get('core', 'SQL_ALCHEMY_CONN')) 

    command.upgrade(config, 'heads') 

 

 

def resetdb(): 

    ''' 

    Clear out the database 

    ''' 

    from airflow import models 

 

    logging.info("Dropping tables that exist") 

    models.Base.metadata.drop_all(settings.engine) 

    mc = MigrationContext.configure(settings.engine) 

    if mc._version.exists(settings.engine): 

        mc._version.drop(settings.engine) 

    initdb() 

 

 

def validate_key(k, max_length=250): 

    if not isinstance(k, basestring): 

        raise TypeError("The key has to be a string") 

    elif len(k) > max_length: 

        raise AirflowException( 

            "The key has to be less than {0} characters".format(max_length)) 

    elif not re.match(r'^[A-Za-z0-9_\-\.]+$', k): 

        raise AirflowException( 

            "The key ({k}) has to be made of alphanumeric characters, dashes, " 

            "dots and underscores exclusively".format(**locals())) 

    else: 

        return True 

 

 

def date_range( 

        start_date, 

        end_date=None, 

        num=None, 

        delta=None): 

    """ 

    Get a set of dates as a list based on a start, end and delta, delta 

    can be something that can be added to ``datetime.datetime`` 

    or a cron expression as a ``str`` 

 

    :param start_date: anchor date to start the series from 

    :type start_date: datetime.datetime 

    :param end_date: right boundary for the date range 

    :type end_date: datetime.datetime 

    :param num: alternatively to end_date, you can specify the number of 

        number of entries you want in the range. This number can be negative, 

        output will always be sorted regardless 

    :type num: int 

 

    >>> date_range(datetime(2016, 1, 1), datetime(2016, 1, 3), delta=timedelta(1)) 

    [datetime.datetime(2016, 1, 1, 0, 0), datetime.datetime(2016, 1, 2, 0, 0), datetime.datetime(2016, 1, 3, 0, 0)] 

    >>> date_range(datetime(2016, 1, 1), datetime(2016, 1, 3), delta='0 0 * * *') 

    [datetime.datetime(2016, 1, 1, 0, 0), datetime.datetime(2016, 1, 2, 0, 0), datetime.datetime(2016, 1, 3, 0, 0)] 

    >>> date_range(datetime(2016, 1, 1), datetime(2016, 3, 3), delta="0 0 0 * *") 

    [datetime.datetime(2016, 1, 1, 0, 0), datetime.datetime(2016, 2, 1, 0, 0), datetime.datetime(2016, 3, 1, 0, 0)] 

    """ 

    if not delta: 

        return [] 

    if end_date and start_date > end_date: 

        raise Exception("Wait. start_date needs to be before end_date") 

    if end_date and num: 

        raise Exception("Wait. Either specify end_date OR num") 

    if not end_date and not num: 

        end_date = datetime.now() 

 

    delta_iscron = False 

    if isinstance(delta, six.string_types): 

        delta_iscron = True 

        cron = croniter(delta, start_date) 

    else: 

        delta = abs(delta) 

    l = [] 

    if end_date: 

        while start_date <= end_date: 

            l.append(start_date) 

            if delta_iscron: 

                start_date = cron.get_next(datetime) 

            else: 

                start_date += delta 

    else: 

        for i in range(abs(num)): 

            l.append(start_date) 

            if delta_iscron: 

                if num > 0: 

                    start_date = cron.get_next(datetime) 

                else: 

                    start_date = cron.get_prev(datetime) 

            else: 

                if num > 0: 

                    start_date += delta 

                else: 

                    start_date -= delta 

    return sorted(l) 

 

 

def json_ser(obj): 

    """ 

    json serializer that deals with dates 

    usage: json.dumps(object, default=utils.json_ser) 

    """ 

    if isinstance(obj, datetime): 

        obj = obj.isoformat() 

    return obj 

 

 

def alchemy_to_dict(obj): 

    """ 

    Transforms a SQLAlchemy model instance into a dictionary 

    """ 

    if not obj: 

        return None 

    d = {} 

    for c in obj.__table__.columns: 

        value = getattr(obj, c.name) 

        if type(value) == datetime: 

            value = value.isoformat() 

        d[c.name] = value 

    return d 

 

 

def readfile(filepath): 

    f = open(filepath) 

    content = f.read() 

    f.close() 

    return content 

 

 

def apply_defaults(func): 

    """ 

    Function decorator that Looks for an argument named "default_args", and 

    fills the unspecified arguments from it. 

 

    Since python2.* isn't clear about which arguments are missing when 

    calling a function, and that this can be quite confusing with multi-level 

    inheritance and argument defaults, this decorator also alerts with 

    specific information about the missing arguments. 

    """ 

    @wraps(func) 

    def wrapper(*args, **kwargs): 

        if len(args) > 1: 

            raise AirflowException( 

                "Use keyword arguments when initializing operators") 

        dag_args = {} 

        dag_params = {} 

        if 'dag' in kwargs and kwargs['dag']: 

            dag = kwargs['dag'] 

            dag_args = copy(dag.default_args) or {} 

            dag_params = copy(dag.params) or {} 

 

        params = {} 

        if 'params' in kwargs: 

            params = kwargs['params'] 

        dag_params.update(params) 

 

        default_args = {} 

        if 'default_args' in kwargs: 

            default_args = kwargs['default_args'] 

            if 'params' in default_args: 

                dag_params.update(default_args['params']) 

                del default_args['params'] 

 

        dag_args.update(default_args) 

        default_args = dag_args 

        arg_spec = inspect.getargspec(func) 

        num_defaults = len(arg_spec.defaults) if arg_spec.defaults else 0 

        non_optional_args = arg_spec.args[:-num_defaults] 

        if 'self' in non_optional_args: 

            non_optional_args.remove('self') 

        for arg in func.__code__.co_varnames: 

            if arg in default_args and arg not in kwargs: 

                kwargs[arg] = default_args[arg] 

        missing_args = list(set(non_optional_args) - set(kwargs)) 

        if missing_args: 

            msg = "Argument {0} is required".format(missing_args) 

            raise AirflowException(msg) 

 

        kwargs['params'] = dag_params 

 

        result = func(*args, **kwargs) 

        return result 

    return wrapper 

 

 

def ask_yesno(question): 

    yes = set(['yes', 'y']) 

    no = set(['no', 'n']) 

 

    done = False 

    print(question) 

    while not done: 

        choice = input().lower() 

        if choice in yes: 

            return True 

        elif choice in no: 

            return False 

        else: 

            print("Please respond by yes or no.") 

 

 

def send_email(to, subject, html_content, files=None, dryrun=False): 

    """ 

    Send an email with html content 

 

    >>> send_email('test@example.com', 'foo', '<b>Foo</b> bar', ['/dev/null'], dryrun=True) 

    """ 

    SMTP_MAIL_FROM = configuration.get('smtp', 'SMTP_MAIL_FROM') 

 

    if isinstance(to, basestring): 

        if ',' in to: 

            to = to.split(',') 

        elif ';' in to: 

            to = to.split(';') 

        else: 

            to = [to] 

 

    msg = MIMEMultipart('alternative') 

    msg['Subject'] = subject 

    msg['From'] = SMTP_MAIL_FROM 

    msg['To'] = ", ".join(to) 

    mime_text = MIMEText(html_content, 'html') 

    msg.attach(mime_text) 

 

    for fname in files or []: 

        basename = os.path.basename(fname) 

        with open(fname, "rb") as f: 

            msg.attach(MIMEApplication( 

                f.read(), 

                Content_Disposition='attachment; filename="%s"' % basename, 

                Name=basename 

            )) 

 

    send_MIME_email(SMTP_MAIL_FROM, to, msg, dryrun) 

 

 

def send_MIME_email(e_from, e_to, mime_msg, dryrun=False): 

    SMTP_HOST = configuration.get('smtp', 'SMTP_HOST') 

    SMTP_PORT = configuration.getint('smtp', 'SMTP_PORT') 

    SMTP_USER = configuration.get('smtp', 'SMTP_USER') 

    SMTP_PASSWORD = configuration.get('smtp', 'SMTP_PASSWORD') 

    SMTP_STARTTLS = configuration.getboolean('smtp', 'SMTP_STARTTLS') 

 

    if not dryrun: 

        s = smtplib.SMTP(SMTP_HOST, SMTP_PORT) 

        if SMTP_STARTTLS: 

            s.starttls() 

        if SMTP_USER and SMTP_PASSWORD: 

            s.login(SMTP_USER, SMTP_PASSWORD) 

        logging.info("Sent an alert email to " + str(e_to)) 

        s.sendmail(e_from, e_to, mime_msg.as_string()) 

        s.quit() 

 

 

def import_module_attrs(parent_module_globals, module_attrs_dict): 

    ''' 

    Attempts to import a set of modules and specified attributes in the 

    form of a dictionary. The attributes are copied in the parent module's 

    namespace. The function returns a list of attributes names that can be 

    affected to __all__. 

 

    This is used in the context of ``operators`` and ``hooks`` and 

    silence the import errors for when libraries are missing. It makes 

    for a clean package abstracting the underlying modules and only 

    brings functional operators to those namespaces. 

    ''' 

    imported_attrs = [] 

    for mod, attrs in list(module_attrs_dict.items()): 

        try: 

            path = os.path.realpath(parent_module_globals['__file__']) 

            folder = os.path.dirname(path) 

            f, filename, description = imp.find_module(mod, [folder]) 

            module = imp.load_module(mod, f, filename, description) 

            for attr in attrs: 

                parent_module_globals[attr] = getattr(module, attr) 

                imported_attrs += [attr] 

        except Exception as err: 

            logging.debug("Error importing module {mod}: {err}".format( 

                mod=mod, err=err)) 

    return imported_attrs 

 

 

def is_in(obj, l): 

    """ 

    Checks whether an object is one of the item in the list. 

    This is different from ``in`` because ``in`` uses __cmp__ when 

    present. Here we change based on the object itself 

    """ 

    for item in l: 

        if item is obj: 

            return True 

    return False 

 

 

@contextmanager 

def TemporaryDirectory(suffix='', prefix=None, dir=None): 

    name = mkdtemp(suffix=suffix, prefix=prefix, dir=dir) 

    try: 

        yield name 

    finally: 

            try: 

                shutil.rmtree(name) 

            except OSError as e: 

                # ENOENT - no such file or directory 

                if e.errno != errno.ENOENT: 

                    raise e 

 

 

class AirflowTaskTimeout(Exception): 

    pass 

 

 

class timeout(object): 

    """ 

    To be used in a ``with`` block and timeout its content. 

    """ 

    def __init__(self, seconds=1, error_message='Timeout'): 

        self.seconds = seconds 

        self.error_message = error_message 

 

    def handle_timeout(self, signum, frame): 

        logging.error("Process timed out") 

        raise AirflowTaskTimeout(self.error_message) 

 

    def __enter__(self): 

        signal.signal(signal.SIGALRM, self.handle_timeout) 

        signal.alarm(self.seconds) 

 

    def __exit__(self, type, value, traceback): 

        signal.alarm(0) 

 

 

def is_container(obj): 

    """ 

    Test if an object is a container (iterable) but not a string 

    """ 

    return hasattr(obj, '__iter__') and not isinstance(obj, basestring) 

 

 

def as_tuple(obj): 

    """ 

    If obj is a container, returns obj as a tuple. 

    Otherwise, returns a tuple containing obj. 

    """ 

    if is_container(obj): 

        return tuple(obj) 

    else: 

        return tuple([obj]) 

 

 

def round_time(dt, delta, start_date=datetime.min): 

    """ 

    Returns the datetime of the form start_date + i * delta 

    which is closest to dt for any non-negative integer i. 

 

    Note that delta may be a datetime.timedelta or a dateutil.relativedelta 

 

    >>> round_time(datetime(2015, 1, 1, 6), timedelta(days=1)) 

    datetime.datetime(2015, 1, 1, 0, 0) 

    >>> round_time(datetime(2015, 1, 2), relativedelta(months=1)) 

    datetime.datetime(2015, 1, 1, 0, 0) 

    >>> round_time(datetime(2015, 9, 16, 0, 0), timedelta(1), datetime(2015, 9, 14, 0, 0)) 

    datetime.datetime(2015, 9, 16, 0, 0) 

    >>> round_time(datetime(2015, 9, 15, 0, 0), timedelta(1), datetime(2015, 9, 14, 0, 0)) 

    datetime.datetime(2015, 9, 15, 0, 0) 

    >>> round_time(datetime(2015, 9, 14, 0, 0), timedelta(1), datetime(2015, 9, 14, 0, 0)) 

    datetime.datetime(2015, 9, 14, 0, 0) 

    >>> round_time(datetime(2015, 9, 13, 0, 0), timedelta(1), datetime(2015, 9, 14, 0, 0)) 

    datetime.datetime(2015, 9, 14, 0, 0) 

    """ 

 

    if isinstance(delta, six.string_types): 

        # It's cron based, so it's easy 

        cron = croniter(delta, start_date) 

        prev = cron.get_prev(datetime) 

        if prev == start_date: 

            return start_date 

        else: 

            return prev 

 

    # Ignore the microseconds of dt 

    dt -= timedelta(microseconds = dt.microsecond) 

 

    # We are looking for a datetime in the form start_date + i * delta 

    # which is as close as possible to dt. Since delta could be a relative 

    # delta we don't know it's exact length in seconds so we cannot rely on 

    # division to find i. Instead we employ a binary search algorithm, first 

    # finding an upper and lower limit and then disecting the interval until 

    # we have found the closest match. 

 

    # We first search an upper limit for i for which start_date + upper * delta 

    # exceeds dt. 

    upper = 1 

    while start_date + upper*delta < dt: 

        # To speed up finding an upper limit we grow this exponentially by a 

        # factor of 2 

        upper *= 2 

 

    # Since upper is the first value for which start_date + upper * delta 

    # exceeds dt, upper // 2 is below dt and therefore forms a lower limited 

    # for the i we are looking for 

    lower = upper // 2 

 

    # We now continue to intersect the interval between 

    # start_date + lower * delta and start_date + upper * delta 

    # until we find the closest value 

    while True: 

        # Invariant: start + lower * delta < dt <= start + upper * delta 

        # If start_date + (lower + 1)*delta exceeds dt, then either lower or 

        # lower+1 has to be the solution we are searching for 

        if start_date + (lower + 1)*delta >= dt: 

            # Check if start_date + (lower + 1)*delta or 

            # start_date + lower*delta is closer to dt and return the solution 

            if ( 

                    (start_date + (lower + 1) * delta) - dt <= 

                    dt - (start_date + lower * delta)): 

                return start_date + (lower + 1)*delta 

            else: 

                return start_date + lower * delta 

 

        # We intersect the interval and either replace the lower or upper 

        # limit with the candidate 

        candidate = lower + (upper - lower) // 2 

        if start_date + candidate*delta >= dt: 

            upper = candidate 

        else: 

            lower = candidate 

 

    # in the special case when start_date > dt the search for upper will 

    # immediately stop for upper == 1 which results in lower = upper // 2 = 0 

    # and this function returns start_date. 

 

 

def chain(*tasks): 

    """ 

    Given a number of tasks, builds a dependency chain. 

 

    chain(task_1, task_2, task_3, task_4) 

 

    is equivalent to 

 

    task_1.set_downstream(task_2) 

    task_2.set_downstream(task_3) 

    task_3.set_downstream(task_4) 

    """ 

    for up_task, down_task in zip(tasks[:-1], tasks[1:]): 

        up_task.set_downstream(down_task) 

 

 

class AirflowJsonEncoder(json.JSONEncoder): 

    def default(self, obj): 

        # convert dates and numpy objects in a json serializable format 

        if isinstance(obj, datetime): 

            return obj.strftime('%Y-%m-%dT%H:%M:%SZ') 

        elif isinstance(obj, date): 

            return obj.strftime('%Y-%m-%d') 

        elif type(obj) in [np.int_, np.intc, np.intp, np.int8, np.int16, 

                           np.int32, np.int64, np.uint8, np.uint16, 

                           np.uint32, np.uint64]: 

            return int(obj) 

        elif type(obj) in [np.bool_]: 

            return bool(obj) 

        elif type(obj) in [np.float_, np.float16, np.float32, np.float64, 

                           np.complex_, np.complex64, np.complex128]: 

            return float(obj) 

 

        # Let the base class default method raise the TypeError 

        return json.JSONEncoder.default(self, obj)