Introduce slash command matcher (#4717)

With the Unified Slack app we now have two ways of calling commands.
1. Legacy one when command invoked directly: /escalate
2. Unified one: /grafana escalate
On top of that we have different slach commands for each environment:
/escalate-local, /escalate-dev, etc. It was leading to a weird command
to escalate via Unified App in dev u need to type: /grafana-dev
escalate-develop.

To support both, I introduced a matcher function for SlashCommandRoutes.
It allows to simplify handling of such cases without complex workarounds
in an EventAPIEndpoint.


# What this PR does

## Which issue(s) this PR closes

Related to [issue link here]

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## Checklist

- [x] Unit, integration, and e2e (if applicable) tests updated
- [ ] Documentation added (or `pr:no public docs` PR label added if not
required)
- [ ] Added the relevant release notes label (see labels prefixed w/
`release:`). These labels dictate how your PR will
    show up in the autogenerated release notes.

engine/apps/slack/scenarios/paging.py

@@ -15,6 +15,7 @@ from apps.slack.chatops_proxy_routing import make_private_metadata, make_value
 from apps.slack.constants import DIVIDER, PRIVATE_METADATA_MAX_LENGTH
 from apps.slack.errors import SlackAPIChannelNotFoundError
 from apps.slack.scenarios import scenario_step
+from apps.slack.slash_command import SlashCommand
 from apps.slack.types import (
     Block,
     BlockActionType,
@@ -115,7 +116,13 @@ def get_current_items(
 class StartDirectPaging(scenario_step.ScenarioStep):
     """Handle slash command invocation and show initial dialog."""
 
-    command_name = [settings.SLACK_DIRECT_PAGING_SLASH_COMMAND]
+    @staticmethod
+    def matcher(slash_command: SlashCommand) -> bool:
+        # Check if command is /escalate. It's a legacy command we keep for smooth transition.
+        is_legacy_command = slash_command.command == settings.SLACK_DIRECT_PAGING_SLASH_COMMAND
+        # Check if command is /grafana escalate. It's a new command from unified app.
+        is_unified_app_command = slash_command.is_grafana_command and slash_command.subcommand == "escalate"
+        return is_legacy_command or is_unified_app_command
 
     def process_scenario(
         self,
@@ -995,8 +1002,8 @@ STEPS_ROUTING: ScenarioRoute.RoutingSteps = [
     },
     {
         "payload_type": PayloadType.SLASH_COMMAND,
-        "command_name": StartDirectPaging.command_name,
         "step": StartDirectPaging,
+        "matcher": StartDirectPaging.matcher,
     },
     {
         "payload_type": PayloadType.VIEW_SUBMISSION,

engine/apps/slack/slash_command.py

@@ -22,7 +22,8 @@ class SlashCommand:
     @property
     def subcommand(self):
         """
-        Return first arg as subcommand
+        Return first arg as action subcommand: part of command which defines action
+        Example: /grafana escalate -> escalate
         """
         return self.args[0] if len(self.args) > 0 else None
 
@@ -34,3 +35,7 @@ class SlashCommand:
         command = payload["command"].lstrip("/")
         args = payload["text"].split()
         return SlashCommand(command, args)
+
+    @property
+    def is_grafana_command(self):
+        return self.command in ["grafana", "grafana-dev", "grafana-ops", "grafana-prod"]

engine/apps/slack/tests/test_slash_command.py

@@ -14,6 +14,7 @@ def test_parse():
     assert slash_command.command == "grafana"
     assert slash_command.args == ["escalate"]
     assert slash_command.subcommand == "escalate"
+    assert slash_command.is_grafana_command
 
 
 def test_parse_command_without_subcommand():

engine/apps/slack/types/scenario_routes.py

@@ -1,11 +1,15 @@
 import typing
 
+from apps.slack.slash_command import SlashCommand
+
 from .common import EventType, PayloadType
 
 if typing.TYPE_CHECKING:
     from apps.slack.scenarios.scenario_step import ScenarioStep
     from apps.slack.types import BlockActionType, InteractiveMessageActionType
 
+MatcherType = typing.Callable[[SlashCommand], bool]
+
 
 class ScenarioRoute:
     class _Base(typing.TypedDict):
@@ -32,7 +36,7 @@ class ScenarioRoute:
 
     class SlashCommandScenarioRoute(_Base):
         payload_type: typing.Literal[PayloadType.SLASH_COMMAND]
-        command_name: typing.List[str]
+        matcher: MatcherType
 
     class ViewSubmissionScenarioRoute(_Base):
         payload_type: typing.Literal[PayloadType.VIEW_SUBMISSION]

engine/apps/slack/views.py

@@ -361,7 +361,7 @@ class SlackEventApiEndpointView(APIView):
                     cmd = SlashCommand.parse(payload)
                     # Check both command and subcommand for backward compatibility
                     # So both /grafana escalate and /escalate will work.
-                    if cmd.command in route["command_name"] or cmd.subcommand in route["command_name"]:
+                    if route["matcher"](cmd):
                         Step = route["step"]
                         logger.info("Routing to {}".format(Step))
                         step = Step(slack_team_identity, organization, user)