Add eventbus to cloudwatch event target

aws/internal/service/cloudwatchevents/finder/finder.go

@@ -1,9 +1,12 @@
 package finder
 
 import (
+	"fmt"
+
 	"github.com/aws/aws-sdk-go/aws"
 	events "github.com/aws/aws-sdk-go/service/cloudwatchevents"
 	tfevents "github.com/terraform-providers/terraform-provider-aws/aws/internal/service/cloudwatchevents"
+	"github.com/terraform-providers/terraform-provider-aws/aws/internal/service/cloudwatchevents/lister"
 )
 
 func Rule(conn *events.CloudWatchEvents, eventBusName, ruleName string) (*events.DescribeRuleOutput, error) {
@@ -26,3 +29,29 @@ func RuleByID(conn *events.CloudWatchEvents, ruleID string) (*events.DescribeRul
 
 	return Rule(conn, busName, ruleName)
 }
+
+func Target(conn *events.CloudWatchEvents, busName, ruleName, targetId string) (*events.Target, error) {
+	var result *events.Target
+	err := lister.ListAllTargetsForRulePages(conn, busName, ruleName, func(page *events.ListTargetsByRuleOutput, lastPage bool) bool {
+		if page == nil {
+			return !lastPage
+		}
+
+		for _, t := range page.Targets {
+			if targetId == aws.StringValue(t.Id) {
+				result = t
+				return false
+			}
+		}
+
+		return !lastPage
+	})
+	if err != nil {
+		return nil, err
+	}
+
+	if result == nil {
+		return nil, fmt.Errorf("CloudWatch Event Target %q (\"%s/%s\") not found", targetId, busName, ruleName)
+	}
+	return result, nil
+}

aws/internal/service/cloudwatchevents/id.go

@@ -27,3 +27,29 @@ func RuleParseID(id string) (string, string, error) {
 
 	return "", "", fmt.Errorf("unexpected format for ID (%q), expected <event-bus-name>"+ruleIDSeparator+"<rule-name> or <rule-name>", id)
 }
+
+// Terraform state IDs for Targets are not parseable, since the separator used ("-") is also a valid
+// character in both the rule name and the target id.
+
+const targetIDSeparator = "-"
+const targetImportIDSeparator = "/"
+
+func TargetCreateID(eventBusName, ruleName, targetID string) string {
+	id := ruleName + targetIDSeparator + targetID
+	if eventBusName != "" && eventBusName != DefaultEventBusName {
+		id = eventBusName + targetIDSeparator + id
+	}
+	return id
+}
+
+func TargetParseImportID(id string) (string, string, string, error) {
+	parts := strings.Split(id, targetImportIDSeparator)
+	if len(parts) == 2 && parts[0] != "" && parts[1] != "" {
+		return DefaultEventBusName, parts[0], parts[1], nil
+	}
+	if len(parts) == 3 && parts[0] != "" && parts[1] != "" && parts[2] != "" {
+		return parts[0], parts[1], parts[2], nil
+	}
+
+	return "", "", "", fmt.Errorf("unexpected format for ID (%q), expected <event-bus-name>"+targetImportIDSeparator+"<rule-name>"+targetImportIDSeparator+"<target-id> or <rule-name>"+targetImportIDSeparator+"<target-id>", id)
+}

aws/internal/service/cloudwatchevents/lister/list.go

@@ -1,3 +1,17 @@
 //go:generate go run ../../../generators/listpages/main.go -function=ListEventBuses,ListRules,ListTargetsByRule github.com/aws/aws-sdk-go/service/cloudwatchevents
 
 package lister
+
+import (
+	"github.com/aws/aws-sdk-go/aws"
+	events "github.com/aws/aws-sdk-go/service/cloudwatchevents"
+)
+
+func ListAllTargetsForRulePages(conn *events.CloudWatchEvents, busName, ruleName string, fn func(*events.ListTargetsByRuleOutput, bool) bool) error {
+	input := &events.ListTargetsByRuleInput{
+		Rule:         aws.String(ruleName),
+		EventBusName: aws.String(busName),
+		Limit:        aws.Int64(100), // Set limit to allowed maximum to prevent API throttling
+	}
+	return ListTargetsByRulePages(conn, input, fn)
+}

aws/resource_aws_cloudwatch_event_rule_test.go

@@ -37,14 +37,14 @@ func testSweepCloudWatchEventRules(region string) error {
 	var sweeperErrs *multierror.Error
 	var count int
 
-	input := &events.ListRulesInput{}
+	rulesInput := &events.ListRulesInput{}
 
-	err = lister.ListRulesPages(conn, input, func(page *events.ListRulesOutput, lastPage bool) bool {
-		if page == nil {
-			return !lastPage
+	err = lister.ListRulesPages(conn, rulesInput, func(rulesPage *events.ListRulesOutput, lastRulesPage bool) bool {
+		if rulesPage == nil {
+			return !lastRulesPage
 		}
 
-		for _, rule := range page.Rules {
+		for _, rule := range rulesPage.Rules {
 			count++
 			name := aws.StringValue(rule.Name)
 
@@ -59,7 +59,7 @@ func testSweepCloudWatchEventRules(region string) error {
 			}
 		}
 
-		return !lastPage
+		return !lastRulesPage
 	})
 
 	if testSweepSkipSweepError(err) {