agent-spawner: base64 encode the resalloc ticket DATA in env

Fixes: #144

config/agent-spawner/config.yaml

@@ -9,12 +9,14 @@
 #    # agent immediately marked for removal.  `cmd_terminate` exit status is
 #    # just ignored (we need to remove the agent no matter what).
 #
-#    # Prepare the agent.  Variable $RESALLOC_RESOURCE_DATA (base64 encoded)
-#    # is provided in the script environment.  Other variables like
-#    # RESOURCE_NAME, RESOURCE_POOL_ID, etc. are provided as well.
+#    # Prepare the agent.  Variable $AGENT_SPAWNER_RESOURCE_DATA (base64
+#    # encoded, output from `resalloc ticket-wait`) is provided in the script
+#    # environment.
 #    cmd_prepare: /bin/true
+#
 #    # Prepare the agent for termination.  Upon finishing this command, the
-#    # resalloc resource ticket is closed and the resource deallocated.
+#    # resalloc resource ticket is closed and the resource deallocated (the
+#    # $AGENT_SPAWNER_RESOURCE_DATA env var is provided as well).
 #    cmd_terminate: echo noop
 #
 #    # The following commands are executed synchronously by the agent spawner

resalloc_agent_spawner/worker.py

@@ -2,6 +2,8 @@
 Handle certain tasks by a background daemon process.
 """
 
+import base64
+
 from copr_common.background_worker import BackgroundWorker
 
 from resalloc_agent_spawner.helpers import (
@@ -35,16 +37,18 @@ def handle_ticket(self, ticket_id):
         # We know there's self._redis initialized by parent class so we don't
         # create yet another connection.
         redis_dict = self._redis.hgetall(redis_key)
+        ticket_data = base64.b64encode(redis_dict["data"])
+
         if redis_dict["state"] == "PREPARING":
-            if self.cmd_take(redis_dict["group_id"], redis_dict["data"]):
+            if self.cmd_take(redis_dict["group_id"], ticket_data):
                 self._redis.hset(redis_key, "state", "WORKING")
             else:
                 # failed preparation -> prepare removal
                 self._redis.hset(redis_key, "state", "ENDED")
             return
 
         if redis_dict["state"] == "TERMINATING":
-            self.cmd_terminate(redis_dict["group_id"], redis_dict["data"])
+            self.cmd_terminate(redis_dict["group_id"], ticket_data)
             self._redis.hset(redis_key, "state", "ENDED")
 
     def handle_task(self):