Make Timescale listener available using --timescale command line argu…

…ment instead of having to register it in your locusfile.

examples/cmd_line_examples.sh

@@ -3,7 +3,7 @@
 locust -f locustfile_that_imports_locust_plugins.py --help
 # use --help for more info
 
-locust -f locustfile_that_imports_locust_plugins.py -u 1 -t 60 --headless --check-rps 5 --check-fail-ratio 0.05 --check-avg-response-time 50
+locust -f locustfile_that_imports_locust_plugins.py -t 60 --headless --check-rps 5 --check-fail-ratio 0.05 --check-avg-response-time 50
 # Set locust's exit code to failed (2) if any of the following criteria are not met at the end of the run:
 # * At least 5 requests/s
 # * At most 5% errors
@@ -12,3 +12,6 @@ locust -f locustfile_that_imports_locust_plugins.py -u 1 -t 60 --headless --chec
 locust -f locustfile_that_imports_locust_plugins.py -u 5 -t 60 --headless -i 10
 # Stop locust after 10 task iterations (this is an upper bound, so you can be sure no more than 10 of iterations will be done)
 # Note that in a distributed run the parameter needs to be set on the workers, it is (currently) not distributed from master to worker.
+
+locust -f locustfile_that_imports_locust_plugins.py --headless --timescale
+# Log results to a Timescale database, see https://github.com/SvenskaSpel/locust-plugins/blob/master/locust_plugins/timescale/

locust_plugins/__init__.py

@@ -2,6 +2,7 @@
 
 from .wait_time import constant_ips, constant_total_ips
 from .debug import run_single_user
+from .listeners import Timescale
 import locust
 from locust import TaskSet
 from locust.user.task import DefaultTaskSet
@@ -62,7 +63,7 @@ def add_checks_arguments(parser: configargparse.ArgumentParser):
     run_info.add_argument(
         "--grafana-url",
         type=str,
-        help="URL to Grafana dashboard (used by TimescaleListener)",
+        help="URL to Grafana dashboard (used by Timescale listener)",
         env_var="LOCUST_GRAFANA_URL",
         default="http://localhost:3000/d/qjIIww4Zz?",
     )
@@ -76,6 +77,13 @@ def add_checks_arguments(parser: configargparse.ArgumentParser):
     other = parser.add_argument_group(
         "locust-plugins - Extras",
     )
+    other.add_argument(
+        "--timescale",
+        action="store_true",
+        help="Log to a Timescale database, see https://github.com/SvenskaSpel/locust-plugins/blob/master/locust_plugins/timescale/",
+        env_var="LOCUST_TIMESCALE",
+        default=False,
+    )
     # fix for https://github.com/locustio/locust/issues/1085
     other.add_argument(
         "-i",
@@ -94,6 +102,12 @@ def add_checks_arguments(parser: configargparse.ArgumentParser):
     )
 
 
+@events.init.add_listener
+def on_locust_init(environment, **_kwargs):
+    if environment.parsed_options.timescale:
+        listeners.Timescale(env=environment)
+
+
 @events.test_start.add_listener
 def set_up_iteration_limit(environment: Environment, **_kwargs):
     options = environment.parsed_options