def fetch_callback(self, cluster: int, item: int, inst: int):
"""PMDA fetch callback"""
if cluster == Consts.Control.Cluster:
if item == Consts.Control.Register:
json_val = ScriptEncoder(dump_state_data=False).encode(
self.get_ctx_state(pmdaGetContext(), 'register', default={}, delete=True))
return [json_val, 1]
elif item == Consts.Control.Deregister:
json_val = json.dumps(self.get_ctx_state(pmdaGetContext(), 'deregister', default={}, delete=True))
return [json_val, 1]
elif item == Consts.Control.Start:
json_val = json.dumps(self.get_ctx_state(pmdaGetContext(), 'start', default={}, delete=True))
return [json_val, 1]
elif item == Consts.Control.Stop:
json_val = json.dumps(self.get_ctx_state(pmdaGetContext(), 'stop', default={}, delete=True))
return [json_val, 1]
elif cluster == Consts.Info.Cluster:
if item == Consts.Info.Scripts:
id_or_name = self.script_indom.inst_name_lookup(inst)
if id_or_name is None:
return [c_api.PM_ERR_INST, 0]
cluster = self.find_cluster_by_name(id_or_name)
if cluster:
return [cluster.script.code, 1]
return [c_api.PM_ERR_INST, 0]
elif item == Consts.Info.ScriptsJson:
scripts = [cluster.script for cluster in self.clusters.values()]
return [ScriptEncoder(dump_state_data=False).encode(scripts), 1]
elif item == Consts.Info.Tracepoints:
return [self.tracepoints_csv, 1]
elif cluster in self.clusters:
return self.clusters[cluster].fetch_callback(item, inst)
return [c_api.PM_ERR_PMID, 0]
def set_ctx_state(self, key: str, value: Any, ctx=None):
"""set per-context state"""
if ctx is None:
ctx = pmdaGetContext()
if ctx not in self.ctxtab:
self.ctxtab[ctx] = {}
self.ctxtab[ctx][key] = value
def store_callback(self, cluster: int, item: int, inst: int, val: str):
"""PMDA store callback"""
if cluster == Consts.Control.Cluster:
if not self.config.dynamic_scripts.enabled:
self.logger.error("dynamic scripts are disabled in configuration")
return c_api.PM_ERR_PERMISSION
if self.config.dynamic_scripts.auth_enabled:
username = self.get_ctx_state(pmdaGetContext(), 'username')
if username is None:
self.logger.info("permission denied for unauthenticated user")
return c_api.PM_ERR_PERMISSION
elif username not in self.config.dynamic_scripts.allowed_users:
self.logger.info(f"permission denied for user {username}")
return c_api.PM_ERR_PERMISSION
if item == Consts.Control.Register:
script = Script(val)
script.username = self.get_ctx_state(pmdaGetContext(), 'username')
return self.register_script(script)
elif item == Consts.Control.Deregister:
success = True
for script_id in val.split(','):
if not self.deregister_script(script_id):
success = False
if success:
self.set_ctx_state(pmdaGetContext(), 'deregister', {"success": "true"})
return 0
else:
self.set_ctx_state(pmdaGetContext(), 'deregister', {"error": "one or more scripts were not found"})
return c_api.PM_ERR_BADSTORE
elif item == Consts.Control.Start:
cluster = self.find_cluster_by_name(val)
if not cluster:
self.set_ctx_state(pmdaGetContext(), 'start', {"error": "script not found"})
return c_api.PM_ERR_BADSTORE
self.bpftrace_service.start_script(cluster.script.script_id)
self.set_ctx_state(pmdaGetContext(), 'start', {"success": "true"})
return 0
elif item == Consts.Control.Stop:
cluster = self.find_cluster_by_name(val)
if not cluster:
self.set_ctx_state(pmdaGetContext(), 'stop', {"error": "script not found"})
return c_api.PM_ERR_BADSTORE
self.bpftrace_service.stop_script(cluster.script.script_id)
self.set_ctx_state(pmdaGetContext(), 'stop', {"success": "true"})
return 0
return c_api.PM_ERR_PMID
def register_script(self, script: Script, update_ctx=True):
"""register a new bpftrace script"""
script = self.bpftrace_service.register_script(script)
if update_ctx:
self.set_ctx_state(pmdaGetContext(), 'register', script)
if script.state.status == Status.Error:
return c_api.PM_ERR_BADSTORE
cluster = BPFtraceCluster(self, self.logger, self.bpftrace_service, script)
cluster.register_metrics()
self.clusters[cluster.cluster_id] = cluster
self.refresh_script_indom()
return 0
def get_ctx_state(self,
key: str,
ctx=None,
default=None,
delete=False) -> Any:
"""get per-context state"""
if ctx is None:
ctx = pmdaGetContext()
if ctx not in self.ctxtab or key not in self.ctxtab[ctx]:
return default
value = self.ctxtab[ctx].get(key, default)
if delete:
del self.ctxtab[ctx][key]
return value