Define CloudWatch Alarm Payload structure

events/sns.go

@@ -30,3 +30,59 @@ type SNSEntity struct {
 	UnsubscribeURL    string                 `json:"UnsubscribeUrl"`
 	Subject           string                 `json:"Subject"`
 }
+
+type CloudWatchAlarmSNSPayload struct {
+	AlarmName        string                 `json:"AlarmName"`
+	AlarmDescription string                 `json:"AlarmDescription"`
+	AWSAccountID     string                 `json:"AWSAccountId"`
+	NewStateValue    string                 `json:"NewStateValue"`
+	NewStateReason   string                 `json:"NewStateReason"`
+	StateChangeTime  string                 `json:"StateChangeTime"`
+	Region           string                 `json:"Region"`
+	AlarmARN         string                 `json:"AlarmArn"`
+	OldStateValue    string                 `json:"OldStateValue"`
+	Trigger          CloudWatchAlarmTrigger `json:"Trigger"`
+}
+
+type CloudWatchAlarmTrigger struct {
+	Period                           int64                       `json:"Period"`
+	EvaluationPeriods                int64                       `json:"EvaluationPeriods"`
+	ComparisonOperator               string                      `json:"ComparisonOperator"`
+	Threshold                        float64                     `json:"Threshold"`
+	TreatMissingData                 string                      `json:"TreatMissingData"`
+	EvaluateLowSampleCountPercentile string                      `json:"EvaluateLowSampleCountPercentile"`
+	Metrics                          []CloudWatchMetricDataQuery `json:"Metrics,omitempty"`
+	MetricName                       string                      `json:"MetricName,omitempty"`
+	Namespace                        string                      `json:"Namespace,omitempty"`
+	StatisticType                    string                      `json:"StatisticType,omitempty"`
+	Statistic                        string                      `json:"Statistic,omitempty"`
+	Unit                             string                      `json:"Unit,omitempty"`
+	Dimensions                       []CloudWatchDimension       `json:"Dimensions,omitempty"`
+}
+
+type CloudWatchMetricDataQuery struct {
+	Expression string               `json:"Expression,omitempty"`
+	ID         string               `json:"Id"`
+	Label      string               `json:"Label,omitempty"`
+	MetricStat CloudWatchMetricStat `json:"MetricStat,omitempty"`
+	Period     int64                `json:"Period,omitempty"`
+	ReturnData bool                 `json:"ReturnData,omitempty"`
+}
+
+type CloudWatchMetricStat struct {
+	Metric CloudWatchMetric `json:"Metric"`
+	Period int64            `json:"Period"`
+	Stat   string           `json:"Stat"`
+	Unit   string           `json:"Unit,omitempty"`
+}
+
+type CloudWatchMetric struct {
+	Dimensions []CloudWatchDimension `json:"Dimensions,omitempty"`
+	MetricName string                `json:"MetricName,omitempty"`
+	Namespace  string                `json:"Namespace,omitempty"`
+}
+
+type CloudWatchDimension struct {
+	Name  string `json:"name"`
+	Value string `json:"value"`
+}

events/sns_test.go

@@ -33,3 +33,32 @@ func TestSnsEventMarshaling(t *testing.T) {
 func TestSnsMarshalingMalformedJson(t *testing.T) {
 	test.TestMalformedJson(t, SNSEvent{})
 }
+
+func TestCloudWatchAlarmSNSPayloadMarshaling(t *testing.T) {
+	// 1. read JSON from file
+	inputJson := test.ReadJSONFromFile(t, "./testdata/cloudwatch-alarm-sns-payload-single-metric.json")
+
+	// 2. de-serialize into Go object
+	var inputEvent SNSEvent
+	if err := json.Unmarshal(inputJson, &inputEvent); err != nil {
+		t.Errorf("could not unmarshal event. details: %v", err)
+	}
+
+	// 3.retrieve message from the Go object
+	var message = inputEvent.Records[0].SNS.Message
+
+	// 4. de-serialize message into Go object
+	var inputCloudWatchPayload CloudWatchAlarmSNSPayload
+	if err := json.Unmarshal([]byte(message), &inputCloudWatchPayload); err != nil {
+		t.Errorf("could not unmarshal event. details: %v", err)
+	}
+
+	// 5. serialize message to JSON
+	outputJson, err := json.Marshal(inputCloudWatchPayload)
+	if err != nil {
+		t.Errorf("could not marshal event. details: %v", err)
+	}
+
+	// 4. check result
+	assert.JSONEq(t, string(message), string(outputJson))
+}

events/testdata/cloudwatch-alarm-sns-payload-multiple-metrics.json

@@ -0,0 +1,22 @@
+{
+    "Records": [
+        {
+            "EventSource": "aws:sns",
+            "EventVersion": "1.0",
+            "EventSubscriptionArn": "arn:aws:sns:EXAMPLE",
+            "Sns": {
+                "Type": "Notification",
+                "MessageId": "95df01b4-ee98-5cb9-9903-4c221d41eb5e",
+                "TopicArn": "arn:aws:sns:EXAMPLE",
+                "Subject": "TestInvoke",
+                "Message": "{\"AlarmName\":\"EXAMPLE\",\"AlarmDescription\":\"EXAMPLE\",\"AWSAccountId\":\"EXAMPLE\",\"NewStateValue\":\"ALARM\",\"NewStateReason\":\"Threshold Crossed: 1 out of the last 1 datapoints [1234.0 (06/03/15 17:43:27)] was greater than the threshold (0.0) (minimum 1 datapoint for OK -> ALARM transition).\",\"StateChangeTime\":\"2015-06-03T17:43:27.123+0000\",\"Region\":\"EXAMPLE\",\"AlarmArn\":\"arn:aws:cloudwatch:REGION:ACCOUNT_NUMBER:alarm:EXAMPLE\",\"OldStateValue\":\"INSUFFICIENT_DATA\",\"Trigger\":{\"Period\":60,\"EvaluationPeriods\":1,\"ComparisonOperator\":\"GreaterThanThreshold\",\"Threshold\":0.0,\"TreatMissingData\":\"- TreatMissingData:                    missing\",\"EvaluateLowSampleCountPercentile\":\"\",\"Metrics\":[{\"Expression\":\"m1*1\",\"Id\":\"e1\",\"Label\":\"Expression1\",\"ReturnData\":true},{\"Id\":\"m1\",\"MetricStat\":{\"Metric\":{\"Dimensions\":[{\"value\":\"TestInstance\",\"name\":\"InstanceId\"}],\"MetricName\":\"NetworkOut\",\"Namespace\":\"AWS/EC2\"},\"Period\":60,\"Stat\":\"Average\"},\"ReturnData\":false}]}}",
+                "Timestamp": "2015-06-03T17:43:27.123Z",
+                "SignatureVersion": "1",
+                "Signature": "EXAMPLE",
+                "SigningCertUrl": "EXAMPLE",
+                "UnsubscribeUrl": "EXAMPLE",
+                "MessageAttributes": {}
+            }
+        }
+    ]
+}

events/testdata/cloudwatch-alarm-sns-payload-single-metric.json

@@ -0,0 +1,22 @@
+{
+    "Records": [
+        {
+            "EventSource": "aws:sns",
+            "EventVersion": "1.0",
+            "EventSubscriptionArn": "arn:aws:sns:EXAMPLE",
+            "Sns": {
+                "Type": "Notification",
+                "MessageId": "95df01b4-ee98-5cb9-9903-4c221d41eb5e",
+                "TopicArn": "arn:aws:sns:EXAMPLE",
+                "Subject": "TestInvoke",
+                "Message": "{\"AlarmName\": \"EXAMPLE\",\"AlarmDescription\": \"EXAMPLE\",\"AWSAccountId\": \"123456789012\",\"NewStateValue\": \"ALARM\",\"NewStateReason\": \"Threshold Crossed: 1 out of the last 1 datapoints [1234.0 (06/03/15 17:43:27)] was greater than the threshold (0.0) (minimum 1 datapoint for OK -> ALARM transition).\",\"StateChangeTime\": \"2015-06-03T17:43:27.123+0000\",\"Region\": \"EXAMPLE\",\"AlarmArn\": \"arn:aws:cloudwatch:REGION:ACCOUNT_NUMBER:alarm:EXAMPLE\",\"OldStateValue\": \"INSUFFICIENT_DATA\",\"Trigger\": {\"MetricName\": \"NetworkOut\",\"Namespace\": \"AWS/EC2\",\"StatisticType\": \"Statistic\",\"Statistic\": \"AVERAGE\",\"Unit\": \"Bytes\",\"Dimensions\": [{\"value\": \"TestInstance\",\"name\": \"InstanceId\"}],\"Period\": 60,\"EvaluationPeriods\": 1,\"ComparisonOperator\": \"GreaterThanThreshold\",\"Threshold\": 0.0,\"TreatMissingData\": \"- TreatMissingData:                    missing\",\"EvaluateLowSampleCountPercentile\": \"\"}}",
+                "Timestamp": "2015-06-03T17:43:27.123Z",
+                "SignatureVersion": "1",
+                "Signature": "EXAMPLE",
+                "SigningCertUrl": "EXAMPLE",
+                "UnsubscribeUrl": "EXAMPLE",
+                "MessageAttributes": {}
+            }
+        }
+    ]
+}

go.mod

@@ -3,6 +3,6 @@ module github.com/aws/aws-lambda-go
 go 1.12
 
 require (
-	github.com/stretchr/testify v1.4.0
+	github.com/stretchr/testify v1.5.1
 	github.com/urfave/cli/v2 v2.1.1
 )

go.sum

@@ -1,8 +1,14 @@
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
+github.com/aws/aws-sdk-go v1.31.12 h1:SxRRGyhlCagI0DYkhOg+FgdXGXzRTE3vEX/gsgFaiKQ=
+github.com/aws/aws-sdk-go v1.31.12/go.mod h1:5zCpMtNQVjRREroY7sYe8lOMRSxkhG6MZveU8YkpAk0=
 github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d h1:U+s90UTSYgptZMwQh2aRr3LuazLJIa+Pg3Kc1ylSYVY=
 github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
 github.com/davecgh/go-spew v1.1.0 h1:ZDRjVQ15GmhC3fiQ8ni8+OwkZQO4DARzQgrnXU1Liz8=
 github.com/davecgh/go-spew v1.1.0/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/go-sql-driver/mysql v1.5.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
+github.com/jmespath/go-jmespath v0.3.0 h1:OS12ieG61fsCg5+qLJ+SsW9NicxNkg3b25OyT2yCeUc=
+github.com/jmespath/go-jmespath v0.3.0/go.mod h1:9QtRXoHjLGCJ5IBSaohpXITPlowMeeYCZ7fLUTSywik=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
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 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/russross/blackfriday/v2 v2.0.1 h1:lPqVAte+HuHNfhJ/0LC98ESWRz8afy9tM/0RK8m9o+Q=
@@ -13,8 +19,14 @@ github.com/stretchr/objx v0.1.0 h1:4G4v2dO3VZwixGIRoQ5Lfboy6nUhCyYzaqnIAPPhYs4=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/testify v1.4.0 h1:2E4SXV/wtOkTonXsotYi4li6zVWxYlZuYNCXe9XRJyk=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
+github.com/stretchr/testify v1.5.1 h1:nOGnQDM7FYENwehXlg/kFVnos3rEvtKTjRvOWSzb6H4=
+github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
 github.com/urfave/cli/v2 v2.1.1 h1:Qt8FeAtxE/vfdrLmR3rxR6JRE0RoVmbXu8+6kZtYU4k=
 github.com/urfave/cli/v2 v2.1.1/go.mod h1:SE9GqnLQmjVa0iPEY0f1w3ygNIYcIJ0OKPMoW2caLfQ=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20200202094626-16171245cfb2/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
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