Creates 'greet_guests' example service for the programming guide.

firexapp/tasks/example.py

@@ -1,7 +1,11 @@
 from getpass import getuser
 import time
 
+from firexkit.argument_conversion import SingleArgDecorator
+from firexkit.task import FireXTask
+
 from firexapp.engine.celery import app
+from firexapp.submit.arguments import InputConverter
 
 
 @app.task
@@ -22,6 +26,28 @@ def getusername():
 
 
 # The @app.task() makes this normal python function a FireX Service.
-@app.task()
+@app.task(returns=['greeting'])
 def greet(name=getuser()):
     return 'Hello %s!' % name
+
+
+# Setting bind=True makes the first argument received by the service 'self'. It's most commonly used to invoke
+# (enqueue) other services, but provides much more functionality as outlined here:
+@app.task(bind=True, returns=['guests_greeting'])
+def greet_guests(self: FireXTask, guests):
+    greetings = []
+    for guest in guests:
+        # Create a Celery Signature, see: https://docs.celeryproject.org/en/latest/userguide/canvas.html#signatures
+        greet_signature = greet.s(name=guest)
+        # enqueue_child_and_get_results is useful when you want to block on a service invocation and receive the result
+        # immediately. See the details of other enqueue methods here: ____
+        greet_results = self.enqueue_child_and_get_results(greet_signature)
+        greetings.append(greet_results['greeting'])
+
+    return ' '.join(greetings)
+
+
+@InputConverter.register
+@SingleArgDecorator('guests')
+def to_list(guests):
+    return guests.split(',')

tests/integration_tests/example_flow_tests.py

@@ -23,4 +23,20 @@ def assert_expected_firex_output(self, cmd_output, cmd_err):
         logs_dir = get_log_dir_from_output(cmd_output)
         completion_data = get_completion_report_data(logs_dir)
 
-        assert completion_data['completed']
+        assert completion_data['results']['chain_results']['greeting'] == "Hello John!"
+
+
+class GreetGuestsTest(FlowTestConfiguration):
+
+    def initial_firex_options(self) -> list:
+        return ['submit', '--chain', "greet_guests", "--guests", "John,Mohammad"]
+
+    def assert_expected_return_code(self, ret_value):
+        assert_is_good_run(ret_value)
+
+    def assert_expected_firex_output(self, cmd_output, cmd_err):
+        assert not cmd_err, "no errors expected"
+
+        logs_dir = get_log_dir_from_output(cmd_output)
+        completion_data = get_completion_report_data(logs_dir)
+        assert completion_data['results']['chain_results']['guests_greeting'] == "Hello John! Hello Mohammad!"