class Crawler(object):
"""A processing graph that constitutes a crawler."""
SCHEDULES = {
'disabled': None,
'hourly': timedelta(hours=1),
'daily': timedelta(days=1),
'weekly': timedelta(weeks=1),
'monthly': timedelta(weeks=4)
}
def __init__(self, manager, source_file):
self.manager = manager
self.source_file = source_file
with io.open(source_file, encoding='utf-8') as fh:
self.config_yaml = fh.read()
self.config = yaml.safe_load(self.config_yaml)
self.name = os.path.basename(source_file)
self.name = self.config.get('name', self.name)
self.description = self.config.get('description', self.name)
self.category = self.config.get('category', 'scrape')
self.schedule = self.config.get('schedule', 'disabled')
self.init_stage = self.config.get('init', 'init')
self.delta = Crawler.SCHEDULES.get(self.schedule)
self.delay = int(self.config.get('delay', 0))
self.expire = int(self.config.get('expire', settings.EXPIRE)) * 84600
self.stealthy = self.config.get('stealthy', False)
self.queue = Dataset(conn, self.name)
self.aggregator_config = self.config.get('aggregator', {})
self.stages = {}
for name, stage in self.config.get('pipeline', {}).items():
self.stages[name] = CrawlerStage(self, name, stage)
def check_due(self):
"""Check if the last execution of this crawler is older than
the scheduled interval."""
if self.is_running:
return False
if self.delta is None:
return False
last_run = self.last_run
if last_run is None:
return True
now = datetime.utcnow()
if now > last_run + self.delta:
return True
return False
@property
def aggregator_method(self):
if self.aggregator_config:
method = self.aggregator_config.get("method")
if not method:
return
if ':' in method:
package, method = method.rsplit(':', 1)
module = import_module(package)
return getattr(module, method)
def aggregate(self, context):
if self.aggregator_method:
log.info("Running aggregator for %s" % self.name)
params = self.aggregator_config.get("params", {})
self.aggregator_method(context, params)
def flush(self):
"""Delete all run-time data generated by this crawler."""
self.queue.cancel()
Event.delete(self)
Crawl.flush(self)
def flush_events(self):
Event.delete(self)
def cancel(self):
Crawl.abort_all(self)
self.queue.cancel()
@property
def should_timeout(self):
if self.last_run is None:
return False
now = datetime.utcnow()
return self.last_run < now - timedelta(
seconds=settings.CRAWLER_TIMEOUT) # noqa
def timeout(self):
log.warning("Crawler timed out: %s. Aggregator won't be run",
self.name) # noqa
self.cancel()
def run(self, incremental=None, run_id=None):
"""Queue the execution of a particular crawler."""
state = {
'crawler': self.name,
'run_id': run_id or Job.random_id(),
'incremental': settings.INCREMENTAL
}
if incremental is not None:
state['incremental'] = incremental
# Cancel previous runs:
self.cancel()
# Flush out previous events data but keep the counts:
Event.delete_data(self)
Queue.queue(self.init_stage, state, {})
@property
def is_running(self):
"""Is the crawler currently running?"""
for job in self.queue.get_jobs():
if not job.is_done():
return True
return False
@property
def last_run(self):
return Crawl.last_run(self)
@property
def op_count(self):
"""Total operations performed for this crawler"""
return Crawl.op_count(self)
@property
def runs(self):
return Crawl.runs(self)
@property
def latest_runid(self):
return Crawl.latest_runid(self)
@property
def pending(self):
status = self.queue.get_status()
return status.get('pending')
def flush_tags(self):
pipe = conn.pipeline()
count = 0
for key in conn.scan_iter(make_key(self, 'tag', '*')):
pipe.delete(key)
count += 1
pipe.execute()
log.info("Deleted %d tags", count)
def get(self, name):
return self.stages.get(name)
def __str__(self):
return self.name
def __iter__(self):
return iter(self.stages.values())
def __repr__(self):
return '<Crawler(%s)>' % self.name
class Crawler(object):
"""A processing graph that constitutes a crawler."""
SCHEDULES = {
"disabled": None,
"hourly": timedelta(hours=1),
"daily": timedelta(days=1),
"weekly": timedelta(weeks=1),
"monthly": timedelta(weeks=4),
}
def __init__(self, manager, source_file):
self.manager = manager
self.source_file = source_file
with io.open(source_file, encoding="utf-8") as fh:
self.config_yaml = fh.read()
self.config = yaml.safe_load(self.config_yaml)
self.name = os.path.basename(source_file)
# YAML keys with undefined values will be parsed as `None`.
# eg: with the yaml definition `name: `, `config.get("name", "default_value")`
# will evaluate to `None` instead of `default_value`.
# So in order to avoid setting `self.name` to `None`, we use `or` to
# set the default instead of passing it to `config.get()`
self.name = self.config.get("name") or self.name
self.validate_name()
self.description = self.config.get("description") or self.name
self.category = self.config.get("category") or "scrape"
self.init_stage = self.config.get("init") or "init"
self.delay = int(self.config.get("delay") or 0)
self.expire = int(self.config.get("expire") or settings.EXPIRE) * 84600
self.stealthy = self.config.get("stealthy") or False
self.queue = Dataset(conn, self.name)
self.aggregator_config = self.config.get("aggregator") or {}
self.stages = {}
for name, stage in self.config.get("pipeline", {}).items():
self.stages[name] = CrawlerStage(self, name, stage)
def validate_name(self):
if not re.match(r"^[A-Za-z0-9_-]+$", self.name):
raise ValueError("Invalid crawler name: %s. "
"Allowed characters: A-Za-z0-9_-" % self.name)
@property
def aggregator_method(self):
if self.aggregator_config:
method = self.aggregator_config.get("method")
if not method:
return
# method A: via a named Python entry point
func = get_entry_point("memorious.operations", method)
if func is not None:
return func
# method B: direct import from a module
if ":" in method:
package, method = method.rsplit(":", 1)
module = import_module(package)
return getattr(module, method)
raise ValueError("Unknown method: %s", self.method_name)
def aggregate(self, context):
if self.aggregator_method:
log.info("Running aggregator for %s" % self.name)
params = self.aggregator_config.get("params", {})
self.aggregator_method(context, params)
def flush(self):
"""Delete all run-time data generated by this crawler."""
self.queue.cancel()
Crawl.flush(self)
self.flush_tags()
def flush_tags(self):
tags.delete(prefix=make_key(self, "tag"))
def cancel(self):
Crawl.abort_all(self)
self.queue.cancel()
def run(self, incremental=None, run_id=None):
"""Queue the execution of a particular crawler."""
state = {
"crawler": self.name,
"run_id": run_id or Job.random_id(),
"incremental": settings.INCREMENTAL,
"continue_on_error": settings.CONTINUE_ON_ERROR,
}
if incremental is not None:
state["incremental"] = incremental
# Cancel previous runs:
self.cancel()
init_stage = self.get(self.init_stage)
Queue.queue(init_stage, state, {})
@property
def is_running(self):
"""Is the crawler currently running?"""
for job in self.queue.get_jobs():
if not job.is_done():
return True
return False
@property
def last_run(self):
return Crawl.last_run(self)
@property
def op_count(self):
"""Total operations performed for this crawler"""
return Crawl.op_count(self)
@property
def runs(self):
return Crawl.runs(self)
@property
def latest_runid(self):
return Crawl.latest_runid(self)
@property
def pending(self):
status = self.queue.get_status()
return status.get("pending")
def get(self, name):
return self.stages.get(name)
def __str__(self):
return self.name
def __iter__(self):
return iter(self.stages.values())
def __repr__(self):
return "<Crawler(%s)>" % self.name
class Crawler(object):
"""A processing graph that constitutes a crawler."""
SCHEDULES = {
"disabled": None,
"hourly": timedelta(hours=1),
"daily": timedelta(days=1),
"weekly": timedelta(weeks=1),
"monthly": timedelta(weeks=4),
}
def __init__(self, manager, source_file):
self.manager = manager
self.source_file = source_file
with io.open(source_file, encoding="utf-8") as fh:
self.config_yaml = fh.read()
self.config = yaml.safe_load(self.config_yaml)
self.name = os.path.basename(source_file)
self.name = self.config.get("name", self.name)
self.validate_name()
self.description = self.config.get("description", self.name)
self.category = self.config.get("category", "scrape")
self._schedule = self.config.get("schedule", "disabled")
self.init_stage = self.config.get("init", "init")
self.delta = Crawler.SCHEDULES.get(self.schedule)
self.delay = int(self.config.get("delay", 0))
self.expire = int(self.config.get("expire", settings.EXPIRE)) * 84600
self.stealthy = self.config.get("stealthy", False)
self.queue = Dataset(conn, self.name)
self.aggregator_config = self.config.get("aggregator", {})
self.stages = {}
for name, stage in self.config.get("pipeline", {}).items():
self.stages[name] = CrawlerStage(self, name, stage)
def check_due(self):
"""Check if the last execution of this crawler is older than
the scheduled interval."""
if self.is_running:
return False
if self.delta is None:
return False
last_run = self.last_run
if last_run is None:
return True
now = datetime.utcnow()
if now > last_run + self.delta:
return True
return False
def validate_name(self):
if not re.match(r"^[A-Za-z0-9_-]+$", self.name):
raise ValueError("Invalid crawler name: %s. "
"Allowed characters: A-Za-z0-9_-" % self.name)
@property
def schedule(self):
schedule = Crawl.get_schedule(self) or self._schedule
return schedule if schedule in self.SCHEDULES else "disabled"
@property
def aggregator_method(self):
if self.aggregator_config:
method = self.aggregator_config.get("method")
if not method:
return
# method A: via a named Python entry point
func = get_entry_point("memorious.operations", method)
if func is not None:
return func
# method B: direct import from a module
if ":" in method:
package, method = method.rsplit(":", 1)
module = import_module(package)
return getattr(module, method)
raise ValueError("Unknown method: %s", self.method_name)
def aggregate(self, context):
if self.aggregator_method:
log.info("Running aggregator for %s" % self.name)
params = self.aggregator_config.get("params", {})
self.aggregator_method(context, params)
def flush(self):
"""Delete all run-time data generated by this crawler."""
self.queue.cancel()
Event.delete(self)
Crawl.flush(self)
self.flush_tags()
def flush_tags(self):
tags.delete(prefix=make_key(self, "tag"))
def flush_events(self):
Event.delete(self)
def cancel(self):
Crawl.abort_all(self)
self.queue.cancel()
@property
def should_timeout(self):
if self.last_run is None:
return False
now = datetime.utcnow()
return self.last_run < now - timedelta(
seconds=settings.CRAWLER_TIMEOUT) # noqa
def timeout(self):
log.warning("Crawler timed out: %s. Aggregator won't be run",
self.name) # noqa
self.cancel()
def run(self, incremental=None, run_id=None):
"""Queue the execution of a particular crawler."""
state = {
"crawler": self.name,
"run_id": run_id or Job.random_id(),
"incremental": settings.INCREMENTAL,
}
if incremental is not None:
state["incremental"] = incremental
# Cancel previous runs:
self.cancel()
# Flush out previous events data but keep the counts:
Event.delete_data(self)
init_stage = self.get(self.init_stage)
Queue.queue(init_stage, state, {})
@property
def is_running(self):
"""Is the crawler currently running?"""
for job in self.queue.get_jobs():
if not job.is_done():
return True
return False
@property
def last_run(self):
return Crawl.last_run(self)
@property
def op_count(self):
"""Total operations performed for this crawler"""
return Crawl.op_count(self)
@property
def runs(self):
return Crawl.runs(self)
@property
def latest_runid(self):
return Crawl.latest_runid(self)
@property
def pending(self):
status = self.queue.get_status()
return status.get("pending")
def get(self, name):
return self.stages.get(name)
def __str__(self):
return self.name
def __iter__(self):
return iter(self.stages.values())
def __repr__(self):
return "<Crawler(%s)>" % self.name