Merge lp:~xavpaice/landscape-client-charm/add_tags into lp:landscape-client-charm

[Xav Paice]

Add list of Juju units as tags to client config, and a tags relation for consumption by https://launchpad.net/charm-launchpad-tagger

[lp:~xavpaice/landscape-client-charm/add_tags]

74. By Xav Paice on 2021-08-24

Add Juju availabilty zone to tags

75. By Xav Paice on 2021-08-25

Add tags relation

[Stephan Pampel (stephanpampel)]

Added a comment

[Stephan Pampel (stephanpampel)]

Created an updated implementation: https://code.launchpad.net/~stephanpampel/landscape-client-charm/landscape-client-charm/+merge/411409

Unmerged revisions

75. By Xav Paice on 2021-08-25

Add tags relation

74. By Xav Paice on 2021-08-24

Add Juju availabilty zone to tags

73. By Xav Paice on 2021-08-24

Add list of Juju units as tags to client config

=== modified file 'hooks/common.py'
--- hooks/common.py	2021-02-18 02:37:59 +0000
+++ hooks/common.py	2021-08-25 21:10:55 +0000
@@ -64,8 +64,13 @@
         return check_output(["juju-log", message])
 
     def _run_juju_tool(self, command):
-        """Run specified Juju tool and parse json output."""
-        output = check_output([command, "--format", "json"])
+        """Run specified Juju tool and parse json output.
+
+        @param json: boolean, whether to return output formatted in json.
+        @param switches: list, additional arguments to the command to be run
+        """
+        cmd = [command, "--format", "json"]
+        output = check_output(cmd)
         return json.loads(output) if output else {}
 
 
 
=== modified file 'hooks/hooks.py'
--- hooks/hooks.py	2019-04-04 16:07:48 +0000
+++ hooks/hooks.py	2021-08-25 21:10:55 +0000
@@ -1,4 +1,5 @@
 import apt_pkg
+import re
 import sys
 import socket
 import os
@@ -11,6 +12,7 @@
 from subprocess import CalledProcessError
 
 from charmhelpers import fetch
+from charmhelpers.core.unitdata import kv
 from charmhelpers.core import hookenv
 
 from common import (
@@ -21,6 +23,7 @@
 from install import install
 
 CERT_FILE = "/etc/ssl/certs/landscape_server_ca.crt"
+JUJU_AGENT_DIR = "/var/lib/juju/agents"
 
 JUJU_BROKER = JujuBroker()
 LANDSCAPE_BROKER = LandscapeBroker()
@@ -38,6 +41,32 @@
                        landscape_broker=landscape_broker)
 
 
[e-mail]("tags-relation-changed")
+def tags_relation(juju_broker=JUJU_BROKER, hookenv=hookenv):
+    """Run hook to populate tags relation data."""
+    tags_list = get_tags(hookenv.config())
+
+    for relation in hookenv.relation_ids("tags"):
+        hookenv.relation_set(relation_id=relation,
+                             tags=",".join(tags_list),
+                             computer_title=socket.gethostname()
+                             )
+
+
[e-mail]("update-status")
+def update_status():
+    """Update status hook."""
+
+    kvstore = kv()
+    stored_tags = set(kvstore.get("tags"))
+    current_tags = set(get_tags(hookenv.config()))
+    if stored_tags == current_tags:
+        # Assumption that we have already set relation data to match stored tags
+        return
+    config_changed()
+    tags_relation()
+
+
 @hooks.hook("config-changed")
 def config_changed(relation_data=None, hookenv=hookenv, fetch=fetch,
                    landscape_broker=LANDSCAPE_BROKER):
@@ -61,8 +90,16 @@
                 set_config[key] = value.strip()
             else:
                 set_config[key] = value
+    # Add tags for Juju units installed on this machine
+    tags_list = get_tags(set_config)
 
+    kvstore = kv()
+    kvstore.set(key="tags", value=tags_list)
+    kvstore.flush()
+    set_config["tags"] = ",".join(tags_list)
+    tags_relation()
     relation_data.update(set_config)
+
     if service_config.get("disable-unattended-upgrades"):
         Cnf = apt_pkg.Configuration()
         apt_dir = '/etc/apt/apt.conf.d'
@@ -72,13 +109,34 @@
             hookenv.log("Disabling unattended upgrades")
             with open(apt_dir + '/99landscapeoverride', 'w') as override_file:
                 override_file.write(disable_upgrades)
+
     if relation_data.get("ssl-public-key", "").startswith("base64:"):
         _write_certificate(relation_data["ssl-public-key"][7:], CERT_FILE)
         relation_data["ssl-public-key"] = CERT_FILE
+
     if "account-name" in relation_data:
         return landscape_broker.update_client_config(relation_data)
 
 
+def get_tags(config):
+    """Return a list of tags to use for this unit."""
+    tags_list = [tag.strip() for tag in config.get("tags").split(",")]
+    tags_list.extend(juju_application_tags())
+    zone = os.getenv("JUJU_AVAILABILITY_ZONE")
+    if zone:
+        tags_list.append(zone)
+    return tags_list
+
+
+def juju_application_tags():
+    """Return a list of tags to add for each Juju application."""
+    agent_dirs = os.listdir(JUJU_AGENT_DIR)
+    regex = re.compile(r"^unit-(\w+-*\w*)-\d+")
+    app_tags = [regex.match(agent)[1] for agent in
+                agent_dirs if regex.match(agent)]
+    return app_tags
+
+
 @hooks.hook("upgrade-charm")
 def upgrade_charm(landscape_broker=LANDSCAPE_BROKER):
     """Idempotently upgrades state from older charms."""
 
=== added symlink 'hooks/update-status'
=== target is 'hooks'
=== modified file 'metadata.yaml'
--- metadata.yaml	2020-02-19 17:40:49 +0000
+++ metadata.yaml	2021-08-25 21:10:55 +0000
@@ -22,3 +22,7 @@
   ceph-client:
     interface: ceph-client
     scope: container
+provides:
+  tags:
+    interface: landscape-tags
+