# limitations under the License.
# ==================================================================================
"""
-This framework for Python Xapps provides classes that Xapp writers should
-instantiate and/or subclass depending on their needs.
+This framework for Python Xapps provides classes that Xapp writers
+should instantiate and/or subclass depending on their needs.
"""
import json
# environment variable with path to configuration file
CONFIG_FILE_ENV = "CONFIG_FILE"
-# Private base class; not for direct client use
-
class _BaseXapp:
"""
- This base class initializes RMR by starting a thread that checks for
- incoming messages, and provisions an SDL object.
-
- If environment variable CONFIG_FILE_ENV is defined, and that value is a
- path to an existing file, a watcher is defined to monitor modifications
- (writes) to that file using the Linux kernel's inotify feature, and the
- configuration-change handler function is invoked. The watcher can be
- polled by calling method config_check().
+ This class initializes RMR, starts a thread that checks for incoming
+ messages, provisions an SDL object and optionally creates a
+ config-file watcher. This private base class should not be
+ instantiated by clients directly, but it defines many public methods
+ that may be used by clients.
+
+ If environment variable CONFIG_FILE is defined, and that variable
+ contains a path to an existing file, a watcher is defined to monitor
+ modifications (writes) to that file using the Linux kernel's inotify
+ feature. The watcher must be polled by calling method
+ config_check().
Parameters
----------
- rmr_port: int
- port to listen on
-
- rmr_wait_for_ready: bool (optional)
- If this is True, then init waits until rmr is ready to send, which
- includes having a valid routing file. This can be set to
- False if the client only wants to *receive only*.
-
- use_fake_sdl: bool (optional)
- if this is True, it uses the dbaas "fake dict backend" instead
- of Redis or other backends. Set this to true when developing
- an xapp or during unit testing to eliminate the need for DBAAS.
-
- post_init: function (optional)
- Runs this user-provided function after the base xapp is
- initialized; its signature should be post_init(self)
+ rmr_port: int (optional, default is 4562)
+ Port on which the RMR library listens for incoming messages.
+
+ rmr_wait_for_ready: bool (optional, default is True)
+ If this is True, then init waits until RMR is ready to send,
+ which includes having a valid routing file. This can be set
+ to False if the client wants to *receive only*.
+
+ use_fake_sdl: bool (optional, default is False)
+ if this is True, it uses the DBaaS "fake dict backend" instead
+ of Redis or other backends. Set this to True when developing
+ an xapp or during unit testing to eliminate the need for DBaaS.
+
+ post_init: function (optional, default is None)
+ Runs this user-provided function at the end of the init method;
+ its signature should be post_init(self)
"""
def __init__(self, rmr_port=4562, rmr_wait_for_ready=True, use_fake_sdl=False, post_init=None):
# Convenience (pass-thru) function for invoking SDL.
- def sdl_set(self, ns, key, value, usemsgpack=True):
+ def sdl_set(self, namespace, key, value, usemsgpack=True):
"""
Stores a key-value pair to SDL, optionally serializing the value
to bytes using msgpack.
Parameters
----------
- ns: string
+ namespace: string
SDL namespace
key: string
SDL key
that is serializable by msgpack.
If usemsgpack is False, the value must be bytes.
"""
- self._sdl.set(ns, key, value, usemsgpack)
+ self._sdl.set(namespace, key, value, usemsgpack)
- def sdl_get(self, ns, key, usemsgpack=True):
+ def sdl_get(self, namespace, key, usemsgpack=True):
"""
Gets the value for the specified namespace and key from SDL,
optionally deserializing stored bytes using msgpack.
Parameters
----------
- ns: string
+ namespace: string
SDL namespace
key: string
SDL key
See the usemsgpack parameter for an explanation of the returned value type.
Answers None if the key is not found.
"""
- return self._sdl.get(ns, key, usemsgpack)
+ return self._sdl.get(namespace, key, usemsgpack)
- def sdl_find_and_get(self, ns, prefix, usemsgpack=True):
+ def sdl_find_and_get(self, namespace, prefix, usemsgpack=True):
"""
Gets all key-value pairs in the specified namespace
with keys that start with the specified prefix,
Parameters
----------
- ns: string
+ nnamespaces: string
SDL namespace
prefix: string
the key prefix
but is either a Python object or raw bytes as discussed above.
Answers an empty dictionary if no keys matched the prefix.
"""
- return self._sdl.find_and_get(ns, prefix, usemsgpack)
+ return self._sdl.find_and_get(namespace, prefix, usemsgpack)
- def sdl_delete(self, ns, key):
+ def sdl_delete(self, namespace, key):
"""
Deletes the key-value pair with the specified key in the specified namespace.
Parameters
----------
- ns: string
+ namespace: string
SDL namespace
key: string
SDL key
"""
- self._sdl.delete(ns, key)
+ self._sdl.delete(namespace, key)
# Health
class RMRXapp(_BaseXapp):
"""
- Represents an Xapp that reacts only to RMR messages; i.e., when
- messages are received, the Xapp does something. When run is called,
- the xapp framework waits for RMR messages, and calls the appropriate
- client-registered consume callback on each.
-
- If environment variable CONFIG_FILE_ENV is defined, and that value is a
- path to an existing file, the configuration-change handler is invoked at
- startup and on each configuration-file write event. If no handler is
- supplied, this class defines a default handler that logs each invocation.
+ Represents an Xapp that reacts only to RMR messages; i.e., the Xapp
+ only performs an action when a message is received. Clients should
+ invoke the run method, which has a loop that waits for RMR messages
+ and calls the appropriate client-registered consume callback on each.
+
+ If environment variable CONFIG_FILE is defined, and that variable
+ contains a path to an existing file, this class polls a watcher
+ defined on that file to detect file-write events, and invokes a
+ configuration-change handler on each event. The handler is also
+ invoked at startup. If no handler function is supplied to the
+ constructor, this class defines a default handler that only logs a
+ message.
Parameters
----------
default_handler: function
- A function with the signature (summary, sbuf) to be called
- when a message type is received for which no other handler is registered.
+ A function with the signature (summary, sbuf) to be called when a
+ message type is received for which no other handler is registered.
default_handler argument summary: dict
The RMR message summary, a dict of key-value pairs
default_handler argument sbuf: ctypes c_void_p
# the user can override this and register their own handler
# if they wish since the "last registered callback wins".
def handle_healthcheck(self, summary, sbuf):
- ok = self.healthcheck()
- payload = b"OK\n" if ok else b"ERROR [RMR or SDL is unhealthy]\n"
+ healthy = self.healthcheck()
+ payload = b"OK\n" if healthy else b"ERROR [RMR or SDL is unhealthy]\n"
self.rmr_rts(sbuf, new_payload=payload, new_mtype=RIC_HEALTH_CHECK_RESP)
self.rmr_free(sbuf)
Code Review / ric-plt / xapp-frame-py.git / commitdiff