1、mac 上安装luigi
pip install luigi
pip install boto3 (luigi依赖 boto3）
2、基本概念
class Streams(luigi.Task):
"""
Faked version right now, just generates bogus data.
"""
date = luigi.DateParameter()
def run(self):
"""
Generates bogus data and writes it into the :py:meth:`~.Streams.output` target.
"""
with self.output().open('w') as output:
for _ in range(1000):
output.write('{} {} {}\n'.format(
random.randint(0, 999),
random.randint(0, 999),
random.randint(0, 999)))
def output(self):
"""
Returns the target output for this task.
In this case, a successful execution of this task will create a file in the local file system.
:return: the target output for this task.
:rtype: object (:py:class:`luigi.target.Target`)
"""
return luigi.LocalTarget(self.date.strftime('data/streams_%Y_%m_%d_faked.tsv'))
class AggregateArtists(luigi.Task):
"""
This task runs over the target data returned by :py:meth:`~/.Streams.output` and
writes the result into its :py:meth:`~.AggregateArtists.output` target (local file).
"""
date_interval = luigi.DateIntervalParameter()
def output(self):
"""
Returns the target output for this task.
In this case, a successful execution of this task will create a file on the local filesystem.
:return: the target output for this task.
:rtype: object (:py:class:`luigi.target.Target`)
"""
return luigi.LocalTarget("data/artist_streams_{}.tsv".format(self.date_interval))
def requires(self):
"""
This task's dependencies:
* :py:class:`~.Streams`
:return: list of object (:py:class:`luigi.task.Task`)
"""
return [Streams(date) for date in self.date_interval]
def run(self):
artist_count = defaultdict(int)
for t in self.input():
with t.open('r') as in_file:
for line in in_file:
_, artist, track = line.strip().split()
artist_count[artist] += 1
with self.output().open('w') as out_file:
for artist, count in six.iteritems(artist_count):
out_file.write('{}\t{}\n'.format(artist, count))
run()是这个task要执行的内容
requires()是这个task所依赖的任务，这里依赖一系列的Stream
output()是这个task的输出
input()这个是所依赖的task产生的输出
二、使用central planner
先用
luigid --background --pidfile <PATH_TO_PIDFILE> --logdir <PATH_TO_LOGDIR> --state-path <PATH_TO_STATEFILE>
打开liguid server
然后运行任务，比如：
luigi --module top_artists2 Top10Artists --date-interval 2012-06
注意，要去掉 --local-scheduler
然后可以用 localhost:8082来访问现在的任务
如果A -> B，A依赖B，那么B的output可以在A里面直接用input()来使用，如果B的output是若干文件的话，那么在A中的input()也是若干文件，可以用for循环来读取