X-Git-Url: https://osm.etsi.org/gitweb/?p=osm%2FN2VC.git;a=blobdiff_plain;f=modules%2Flibjuju%2Fjuju%2Futils.py;h=1038ed1ee578c594a1b6161fe9cefc9821f0cee9;hp=1d1b24ecd647089ebb335a706350fa61dc29a52a;hb=b2a07f566be558a8b59b8b5dedfe8da5ae1b0132;hpb=68858c1915122c2dbc8999a5cd3229694abf5f3a;ds=sidebyside

diff --git a/modules/libjuju/juju/utils.py b/modules/libjuju/juju/utils.py
index 1d1b24e..1038ed1 100644
--- a/modules/libjuju/juju/utils.py
+++ b/modules/libjuju/juju/utils.py
@@ -3,6 +3,9 @@ import os
 from collections import defaultdict
 from functools import partial
 from pathlib import Path
+import base64
+from pyasn1.type import univ, char
+from pyasn1.codec.der.encoder import encode
 
 
 async def execute_process(*cmd, log=None, loop=None):
@@ -11,11 +14,11 @@ async def execute_process(*cmd, log=None, loop=None):
 
     '''
     p = await asyncio.create_subprocess_exec(
-            *cmd,
-            stdin=asyncio.subprocess.PIPE,
-            stdout=asyncio.subprocess.PIPE,
-            stderr=asyncio.subprocess.PIPE,
-            loop=loop)
+        *cmd,
+        stdin=asyncio.subprocess.PIPE,
+        stdout=asyncio.subprocess.PIPE,
+        stderr=asyncio.subprocess.PIPE,
+        loop=loop)
     stdout, stderr = await p.communicate()
     if log:
         log.debug("Exec %s -> %d", cmd, p.returncode)
@@ -46,6 +49,7 @@ async def read_ssh_key(loop):
     can be passed on to a model.
 
     '''
+    loop = loop or asyncio.get_event_loop()
     return await loop.run_in_executor(None, _read_ssh_key)
 
 
@@ -71,28 +75,91 @@ class IdQueue:
             await queue.put(value)
 
 
-async def run_with_interrupt(task, event, loop=None):
+async def block_until(*conditions, timeout=None, wait_period=0.5, loop=None):
+    """Return only after all conditions are true.
+
+    """
+    async def _block():
+        while not all(c() for c in conditions):
+            await asyncio.sleep(wait_period, loop=loop)
+    await asyncio.wait_for(_block(), timeout, loop=loop)
+
+
+async def run_with_interrupt(task, *events, loop=None):
     """
-    Awaits a task while allowing it to be interrupted by an `asyncio.Event`.
+    Awaits a task while allowing it to be interrupted by one or more
+    `asyncio.Event`s.
 
-    If the task finishes without the event becoming set, the results of the
-    task will be returned.  If the event becomes set, the task will be
-    cancelled ``None`` will be returned.
+    If the task finishes without the events becoming set, the results of the
+    task will be returned.  If the event become set, the task will be cancelled
+    ``None`` will be returned.
 
     :param task: Task to run
-    :param event: An `asyncio.Event` which, if set, will interrupt `task`
-        and cause it to be cancelled.
+    :param events: One or more `asyncio.Event`s which, if set, will interrupt
+        `task` and cause it to be cancelled.
     :param loop: Optional event loop to use other than the default.
     """
     loop = loop or asyncio.get_event_loop()
-    event_task = loop.create_task(event.wait())
-    done, pending = await asyncio.wait([task, event_task],
+    task = asyncio.ensure_future(task, loop=loop)
+    event_tasks = [loop.create_task(event.wait()) for event in events]
+    done, pending = await asyncio.wait([task] + event_tasks,
                                        loop=loop,
                                        return_when=asyncio.FIRST_COMPLETED)
     for f in pending:
-        f.cancel()
-    result = [f.result() for f in done if f is not event_task]
-    if result:
-        return result[0]
+        f.cancel()  # cancel unfinished tasks
+    for f in done:
+        f.exception()  # prevent "exception was not retrieved" errors
+    if task in done:
+        return task.result()  # may raise exception
     else:
         return None
+
+
+class Addrs(univ.SequenceOf):
+    componentType = char.PrintableString()
+
+
+class RegistrationInfo(univ.Sequence):
+    """
+    ASN.1 representation of:
+
+    type RegistrationInfo struct {
+    User string
+
+        Addrs []string
+
+        SecretKey []byte
+
+        ControllerName string
+    }
+    """
+    pass
+
+
+def generate_user_controller_access_token(username, controller_endpoints, secret_key, controller_name):
+    """" Implement in python what is currently done in GO
+    https://github.com/juju/juju/blob/a5ab92ec9b7f5da3678d9ac603fe52d45af24412/cmd/juju/user/utils.go#L16
+
+    :param username: name of the user to register
+    :param controller_endpoints: juju controller endpoints list in the format <ip>:<port>
+    :param secret_key: base64 encoded string of the secret-key generated by juju
+    :param controller_name: name of the controller to register to.
+    """
+
+    # Secret key is returned as base64 encoded string in:
+    # https://websockets.readthedocs.io/en/stable/_modules/websockets/protocol.html#WebSocketCommonProtocol.recv
+    # Deconding it before marshalling into the ASN.1 message
+    secret_key = base64.b64decode(secret_key)
+    addr = Addrs()
+    for endpoint in controller_endpoints:
+        addr.append(endpoint)
+
+    registration_string = RegistrationInfo()
+    registration_string.setComponentByPosition(0, char.PrintableString(username))
+    registration_string.setComponentByPosition(1, addr)
+    registration_string.setComponentByPosition(2, univ.OctetString(secret_key))
+    registration_string.setComponentByPosition(3, char.PrintableString(controller_name))
+    registration_string = encode(registration_string)
+    remainder = len(registration_string) % 3
+    registration_string += b"\0" * (3 - remainder)
+    return base64.urlsafe_b64encode(registration_string)