Source code for swh.scheduler.api.server
# Copyright (C) 2018-2022 The Software Heritage developers
# See the AUTHORS file at the top-level directory of this distribution
# License: GNU General Public License version 3, or any later version
# See top-level LICENSE file for more information
import logging
import os
from typing import Dict
from swh.core import config
from swh.core.api import JSONFormatter, MsgpackFormatter, RPCServerApp
from swh.core.api import encode_data_server as encode_data
from swh.core.api import error_handler, negotiate
from swh.scheduler import get_scheduler
from swh.scheduler.exc import SchedulerException
from swh.scheduler.interface import SchedulerInterface
from .serializers import DECODERS, ENCODERS
scheduler = None
[docs]
def get_global_scheduler():
global scheduler
if not scheduler:
scheduler = get_scheduler(**app.config["scheduler"])
return scheduler
[docs]
class SchedulerServerApp(RPCServerApp):
extra_type_decoders = DECODERS
extra_type_encoders = ENCODERS
app = SchedulerServerApp(
__name__, backend_class=SchedulerInterface, backend_factory=get_global_scheduler
)
[docs]
@app.errorhandler(SchedulerException)
def argument_error_handler(exception):
return error_handler(exception, encode_data, status_code=400)
[docs]
@app.errorhandler(Exception)
def my_error_handler(exception):
return error_handler(exception, encode_data)
[docs]
def has_no_empty_params(rule):
return len(rule.defaults or ()) >= len(rule.arguments or ())
[docs]
@app.route("/")
def index():
return """<html>
<head><title>Software Heritage scheduler RPC server</title></head>
<body>
<p>You have reached the
<a href="https://www.softwareheritage.org/">Software Heritage</a>
scheduler RPC server.<br />
See its
<a href="https://docs.softwareheritage.org/devel/swh-scheduler/">documentation
and API</a> for more information</p>
</body>
</html>"""
[docs]
@app.route("/site-map")
@negotiate(MsgpackFormatter)
@negotiate(JSONFormatter)
def site_map():
links = []
for rule in app.url_map.iter_rules():
if has_no_empty_params(rule) and hasattr(SchedulerInterface, rule.endpoint):
links.append(
dict(
rule=rule.rule,
description=getattr(SchedulerInterface, rule.endpoint).__doc__,
)
)
# links is now a list of url, endpoint tuples
return links
[docs]
def load_and_check_config(config_path: str, type: str = "postgresql") -> Dict:
"""Check the minimal configuration is set to run the api or raise an
error explanation.
Args:
config_path: Configuration file path to load
type: Configuration type, for 'postgresql' type (the default), more checks are
done.
Raises:
Error if the setup is not as expected
Returns:
configuration as a dict
"""
if not config_path:
raise EnvironmentError("Configuration file must be defined")
if not os.path.exists(config_path):
raise FileNotFoundError(f"Configuration file {config_path} does not exist")
cfg = config.read(config_path)
vcfg = cfg.get("scheduler")
if not vcfg:
raise KeyError("Missing '%scheduler' configuration")
if type == "postgresql":
cls = vcfg.get("cls")
if cls not in ("local", "postgresql"):
raise ValueError(
"The scheduler backend can only be started with a 'postgresql' "
"configuration"
)
db = vcfg.get("db")
if not db:
raise KeyError("Invalid configuration; missing 'db' config entry")
return cfg
api_cfg = None
[docs]
def make_app_from_configfile():
"""Run the WSGI app from the webserver, loading the configuration from
a configuration file.
SWH_CONFIG_FILENAME environment variable defines the
configuration path to load.
"""
global api_cfg
if not api_cfg:
config_path = os.environ.get("SWH_CONFIG_FILENAME")
api_cfg = load_and_check_config(config_path)
app.config.update(api_cfg)
handler = logging.StreamHandler()
app.logger.addHandler(handler)
return app
if __name__ == "__main__":
print('Please use the "swh-scheduler api-server" command')
