Add match conditions to alert handlers

CHANGELOG.md

@@ -4,6 +4,42 @@
 
 ### Release Notes
 
+With this release the technical preview alerting service has been refactored.
+Alert handlers now only ever have a single action and belong to a single topic.
+
+The handler defintion has been simplified as a result.
+Here are some example alert handlers using the new structure:
+
+```yaml
+id: my_handler
+kind: pagerDuty
+options:
+  serviceKey: XXX
+```
+
+```yaml
+id: aggregate_by_1m
+kind: aggregate
+options:
+  interval: 1m
+  topic: aggregated
+```
+
+```yaml
+id: publish_to_system
+kind: publish
+options:
+  topics: [ system ]
+```
+
+To define a handler now you must specify which topic the handler belongs to.
+For example to define the above aggregate handler on the system topic use this command:
+
+```sh
+kapacitor define-handler system aggregate_by_1m.yaml
+```
+
+
 ### Features
 
 - [#1159](https://github.com/influxdata/kapacitor/pulls/1159): Go version 1.7.4 -> 1.7.5
@@ -14,6 +50,11 @@
 - [#1162](https://github.com/influxdata/kapacitor/pulls/1162): Add Pushover integration.
 - [#1221](https://github.com/influxdata/kapacitor/pull/1221): Add `working_cardinality` stat to each node type that tracks the number of groups per node.
 - [#1211](https://github.com/influxdata/kapacitor/issues/1211): Add StateDuration node.
+- [#1209](https://github.com/influxdata/kapacitor/issues/1209): BREAKING: Refactor the Alerting service.
+    The change is completely breaking for the technical preview alerting service, a.k.a. the new alert topic handler features.
+    The change boils down to simplifying how you define and interact with topics.
+    Alert handlers now only ever have a single action and belong to a single topic.
+    See the updated API docs.
 
 ### Bugfixes
 

alert.go

@@ -25,6 +25,7 @@ import (
 	"github.com/influxdata/kapacitor/services/snmptrap"
 	"github.com/influxdata/kapacitor/services/telegram"
 	"github.com/influxdata/kapacitor/services/victorops"
+	"github.com/influxdata/kapacitor/tick/ast"
 	"github.com/influxdata/kapacitor/tick/stateful"
 	"github.com/influxdata/kapacitor/vars"
 	"github.com/pkg/errors"
@@ -388,14 +389,14 @@ func newAlertNode(et *ExecutingTask, n *pipeline.AlertNode, l *log.Logger) (an *
 		}
 
 		an.levels[alert.Info] = statefulExpression
-		an.scopePools[alert.Info] = stateful.NewScopePool(stateful.FindReferenceVariables(n.Info.Expression))
+		an.scopePools[alert.Info] = stateful.NewScopePool(ast.FindReferenceVariables(n.Info.Expression))
 		if n.InfoReset != nil {
 			lstatefulExpression, lexpressionCompileError := stateful.NewExpression(n.InfoReset.Expression)
 			if lexpressionCompileError != nil {
 				return nil, fmt.Errorf("Failed to compile stateful expression for infoReset: %s", lexpressionCompileError)
 			}
 			an.levelResets[alert.Info] = lstatefulExpression
-			an.lrScopePools[alert.Info] = stateful.NewScopePool(stateful.FindReferenceVariables(n.InfoReset.Expression))
+			an.lrScopePools[alert.Info] = stateful.NewScopePool(ast.FindReferenceVariables(n.InfoReset.Expression))
 		}
 	}
 
@@ -405,14 +406,14 @@ func newAlertNode(et *ExecutingTask, n *pipeline.AlertNode, l *log.Logger) (an *
 			return nil, fmt.Errorf("Failed to compile stateful expression for warn: %s", expressionCompileError)
 		}
 		an.levels[alert.Warning] = statefulExpression
-		an.scopePools[alert.Warning] = stateful.NewScopePool(stateful.FindReferenceVariables(n.Warn.Expression))
+		an.scopePools[alert.Warning] = stateful.NewScopePool(ast.FindReferenceVariables(n.Warn.Expression))
 		if n.WarnReset != nil {
 			lstatefulExpression, lexpressionCompileError := stateful.NewExpression(n.WarnReset.Expression)
 			if lexpressionCompileError != nil {
 				return nil, fmt.Errorf("Failed to compile stateful expression for warnReset: %s", lexpressionCompileError)
 			}
 			an.levelResets[alert.Warning] = lstatefulExpression
-			an.lrScopePools[alert.Warning] = stateful.NewScopePool(stateful.FindReferenceVariables(n.WarnReset.Expression))
+			an.lrScopePools[alert.Warning] = stateful.NewScopePool(ast.FindReferenceVariables(n.WarnReset.Expression))
 		}
 	}
 
@@ -422,14 +423,14 @@ func newAlertNode(et *ExecutingTask, n *pipeline.AlertNode, l *log.Logger) (an *
 			return nil, fmt.Errorf("Failed to compile stateful expression for crit: %s", expressionCompileError)
 		}
 		an.levels[alert.Critical] = statefulExpression
-		an.scopePools[alert.Critical] = stateful.NewScopePool(stateful.FindReferenceVariables(n.Crit.Expression))
+		an.scopePools[alert.Critical] = stateful.NewScopePool(ast.FindReferenceVariables(n.Crit.Expression))
 		if n.CritReset != nil {
 			lstatefulExpression, lexpressionCompileError := stateful.NewExpression(n.CritReset.Expression)
 			if lexpressionCompileError != nil {
 				return nil, fmt.Errorf("Failed to compile stateful expression for critReset: %s", lexpressionCompileError)
 			}
 			an.levelResets[alert.Critical] = lstatefulExpression
-			an.lrScopePools[alert.Critical] = stateful.NewScopePool(stateful.FindReferenceVariables(n.CritReset.Expression))
+			an.lrScopePools[alert.Critical] = stateful.NewScopePool(ast.FindReferenceVariables(n.CritReset.Expression))
 		}
 	}
 
@@ -464,7 +465,7 @@ func (a *AlertNode) runAlert([]byte) error {
 
 		// Register Handlers on topic
 		for _, h := range a.handlers {
-			a.et.tm.AlertService.RegisterHandler([]string{a.anonTopic}, h)
+			a.et.tm.AlertService.RegisterAnonHandler(a.anonTopic, h)
 		}
 		// Restore anonTopic
 		a.et.tm.AlertService.RestoreTopic(a.anonTopic)
@@ -707,7 +708,7 @@ func (a *AlertNode) runAlert([]byte) error {
 	a.et.tm.AlertService.CloseTopic(a.anonTopic)
 	// Deregister Handlers on topic
 	for _, h := range a.handlers {
-		a.et.tm.AlertService.DeregisterHandler([]string{a.anonTopic}, h)
+		a.et.tm.AlertService.DeregisterAnonHandler(a.anonTopic, h)
 	}
 	return nil
 }
@@ -730,14 +731,20 @@ func (a *AlertNode) restoreEventState(id string) (alert.Level, time.Time) {
 	var anonFound, topicFound bool
 	// Check for previous state on anonTopic
 	if a.hasAnonTopic() {
-		if state, ok := a.et.tm.AlertService.EventState(a.anonTopic, id); ok {
+		if state, ok, err := a.et.tm.AlertService.EventState(a.anonTopic, id); err != nil {
+			a.incrementErrorCount()
+			a.logger.Printf("E! failed to get event state for anonymous topic %s, event %s: %v", a.anonTopic, id, err)
+		} else if ok {
 			anonTopicState = state
 			anonFound = true
 		}
 	}
 	// Check for previous state on topic.
 	if a.hasTopic() {
-		if state, ok := a.et.tm.AlertService.EventState(a.topic, id); ok {
+		if state, ok, err := a.et.tm.AlertService.EventState(a.topic, id); err != nil {
+			a.incrementErrorCount()
+			a.logger.Printf("E! failed to get event state for topic %s, event %s: %v", a.topic, id, err)
+		} else if ok {
 			topicState = state
 			topicFound = true
 		}

alert/DESIGN.md

@@ -73,40 +73,57 @@ Then alert handlers can be configured to subscribe to the events.
 These alert handlers will be configured via the API.
 Use yaml/json to define the alert handlers.
 
+Here are a few examples:
+
 ```yaml
 id: my_handler
+kind: pagerDuty
+options:
+  serviceKey: XXX
+```
+
+```yaml
+id: aggregate_by_1m
+kind: aggregate
+options:
+  interval: 1m
+  topic: aggregated
+```
 
-topics:
-    - cpu
-    - mem
-
-actions:
-    - kind: aggregate
-      options:
-        groupBy: id
-        interval: 1m
-    - kind: throttle
-      options:
-        count: 10
-        every: 5m
-    - kind: publish
-      options:
-        topics: [ throttled_aggreated ]
-    - kind: pagerDuty
-      options:
-         serviceKey: XXX
+```yaml
+id: publish_to_system
+kind: publish
+options:
+  topics: [ system ]
 ```
 
 ```json
 {
     "id": "my_handler",
-    "topics": ["cpu", "mem"],
-    "actions": [
-        {"kind":"aggregate", "options": {"groupBy":"id","internal":"1m"}},
-        {"kind":"throttle", "options": {"count":10,"every":"5m"}},
-        {"kind":"publish", "options": {"topics":["throttled_aggreated"]}},
-        {"kind":"pagerDuty", "options": {"serviceKey":"XXX"}}
-    ]
+    "kind": "pagerDuty",
+    "options": {
+      "serviceKey": "XXX"
+    }
+}
+```
+
+```json
+{
+    "id": "aggregate_by_1m",
+    "kind": "aggregate",
+    "options": {
+      "interval": "1m"
+    }
+}
+```
+
+```json
+{
+    "id": "publish_to_system",
+    "kind": "publish",
+    "options": {
+      "topics": ["system"]
+    }
 }
 ```