A Serverless plugin to easily add CloudWatch alarms to functions
npm i serverless-plugin-aws-alerts --save-dev OR yarn add --dev serverless-plugin-aws-alerts# serverless.yml plugins: - serverless-plugin-aws-alerts custom: alerts: stages: - production topics: alarm: topic: ${self:service}-${opt:stage}-alerts-alarm notifications: - protocol: email endpoint: name@domain.com # Change this to your email address alarms: - functionErrors - functionThrottlesservice: your-service provider: name: aws runtime: nodejs12.x plugins: - serverless-plugin-aws-alerts custom: alerts: stages: # Optionally - select which stages to deploy alarms to - production - staging dashboards: true nameTemplate: $[functionName]-$[metricName]-Alarm # Optionally - naming template for alarms, can be overwritten in definitions prefixTemplate: $[stackName] # Optionally - override the alarm name prefix topics: ok: ${self:service}-${opt:stage}-alerts-ok alarm: ${self:service}-${opt:stage}-alerts-alarm insufficientData: ${self:service}-${opt:stage}-alerts-insufficientData definitions: # these defaults are merged with your definitions functionErrors: period: 300 # override period customAlarm: actionsEnabled: false # Indicates whether actions should be executed during any changes to the alarm state. The default is TRUE description: 'My custom alarm' namespace: 'AWS/Lambda' nameTemplate: $[functionName]-Duration-IMPORTANT-Alarm # Optionally - naming template for the alarms, overwrites globally defined one prefixTemplate: $[stackName] # Optionally - override the alarm name prefix, overwrites globally defined one metric: duration threshold: 200 statistic: Average period: 300 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanOrEqualToThreshold alarms: - functionThrottles - functionErrors - functionInvocations - functionDuration functions: foo: handler: foo.handler alarms: # merged with function alarms - customAlarm - name: fooAlarm # creates new alarm or overwrites some properties of the alarm (with the same name) from definitions namespace: 'AWS/Lambda' actionsEnabled: false metric: errors # define custom metrics here threshold: 1 statistic: Minimum period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanOrEqualToThresholdYou can create alarms using CloudWatch AnomalyDetection to alarm when data is outside a number of standard deviations of normal, rather than at a static threshold. When using anomaly detection alarms the threshold property specifies the "Anomaly Detection Threshold" seen in the AWS console.
Default alarms can also be updated to be anomaly detection alarms by adding the type: anomalyDetection property.
functions: foo: handler: foo.handler alarms: - name: fooAlarm type: anomalyDetection namespace: 'AWS/Lambda' metric: Invocations threshold: 2 statistic: Sum period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: LessThanLowerOrGreaterThanUpperThreshold bar: handler: bar.handler alarms: - name: functionErrors threshold: 2 type: anomalyDetection comparisonOperator: LessThanLowerOrGreaterThanUpperThreshold - name: functionInvocations threshold: 2 type: anomalyDetection comparisonOperator: LessThanLowerOrGreaterThanUpperThresholdYou can define several topics for alarms. For example you want to have topics for critical alarms reaching your pagerduty, and different topics for noncritical alarms, which just send you emails.
In each alarm definition you have to specify which topics you want to use. In following example you get an email for each function error, pagerduty gets alarm only if there are more than 20 errors in 60s
custom: alerts: topics: critical: ok: topic: ${self:service}-${opt:stage}-critical-alerts-ok notifications: - protocol: https endpoint: https://events.pagerduty.com/integration/.../enqueue alarm: topic: ${self:service}-${opt:stage}-critical-alerts-alarm notifications: - protocol: https endpoint: https://events.pagerduty.com/integration/.../enqueue nonCritical: alarm: topic: ${self:service}-${opt:stage}-nonCritical-alerts-alarm notifications: - protocol: email endpoint: alarms@email.com definitions: # these defaults are merged with your definitions criticalFunctionErrors: namespace: 'AWS/Lambda' metric: Errors threshold: 20 statistic: Sum period: 60 evaluationPeriods: 10 comparisonOperator: GreaterThanOrEqualToThreshold okActions: - critical alarmActions: - critical nonCriticalFunctionErrors: namespace: 'AWS/Lambda' metric: Errors threshold: 1 statistic: Sum period: 60 evaluationPeriods: 10 comparisonOperator: GreaterThanOrEqualToThreshold alarmActions: - nonCritical alarms: - criticalFunctionErrors - nonCriticalFunctionErrors If topic name is specified, plugin assumes that topic does not exist and will create it. To use existing topics, specify ARNs or use CloudFormation (e.g. Fn::ImportValue, Fn::Join and Ref) to refer to existing topics.
custom: alerts: topics: alarm: topic: arn:aws:sns:${self:region}:${self::accountId}:monitoring-${opt:stage}custom: alerts: topics: alarm: topic: Fn::ImportValue: ServiceMonitoring:monitoring-${opt:stage, 'dev'} ok: topic: Fn::Join: - ':' - - arn:aws:sns - Ref: AWS::Region - Ref: AWS::AccountId - example-ok-topic insufficientData: topic: Ref: ExampleInsufficientdataTopic resources: Resources: ExampleInsufficientdataTopic: Type: AWS::SNS::Topic Properties: DisplayName: example-insufficientdata-topic Subscription: - Endpoint: me@example.com Protocol: EMAILYou can configure subscriptions to your SNS topics within your serverless.yml. For each subscription, you'll need to specify a protocol and an endpoint.
The following example will send email notifications to me@example.com for all messages to the Alarm topic:
custom: alerts: topics: alarm: topic: ${self:service}-${opt:stage}-alerts-alarm notifications: - protocol: email endpoint: me@example.comYou can configure notifications to send to webhook URLs, to SMS devices, to other Lambda functions, and more. Check out the AWS docs here for configuration options.
You can monitor a log group for a function for a specific pattern. Do this by adding the pattern key. You can learn about custom patterns at: http://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/FilterAndPatternSyntax.html
The following would create a custom metric log filter based alarm named barExceptions. Any function that included this alarm would have its logs scanned for the pattern exception Bar and if found would trigger an alarm.
custom: alerts: definitions: barExceptions: metric: barExceptions threshold: 0 statistic: Minimum period: 60 evaluationPeriods: 1 comparisonOperator: GreaterThanThreshold pattern: 'exception Bar' bunyanErrors: metric: bunyanErrors threshold: 0 statistic: Sum period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanThreshold pattern: '{$.level > 40}'Note: For custom log metrics, namespace property will automatically be set to stack name (e.g.
fooservice-dev).
You can define custom naming template for the alarms. nameTemplate property under alerts configures naming template for all the alarms, while placing nameTemplate under alarm definition configures (overwrites) it for that specific alarm only. Naming template provides interpolation capabilities, where supported placeholders are:
$[functionName]- function name (e.g.helloWorld)$[functionId]- function logical id (e.g.HelloWorldLambdaFunction)$[metricName]- metric name (e.g.Duration)$[metricId]- metric id (e.g.BunyanErrorsHelloWorldLambdaFunctionfor the log based alarms,$[metricName]otherwise)
Note: All the alarm names are prefixed with stack name (e.g.
fooservice-dev).
The plugin provides some default definitions that you can simply drop into your application. For example:
alerts: alarms: - functionErrors - functionThrottles - functionInvocations - functionDurationIf these definitions do not quite suit i.e. the threshold is too high, you can override a setting without creating a completely new definition.
alerts: definitions: # these defaults are merged with your definitions functionErrors: period: 300 # override period treatMissingData: notBreaching # override treatMissingDataThe default definitions are below.
definitions: functionInvocations: namespace: 'AWS/Lambda' metric: Invocations threshold: 100 statistic: Sum period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanOrEqualToThreshold treatMissingData: missing functionErrors: namespace: 'AWS/Lambda' metric: Errors threshold: 1 statistic: Sum period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanOrEqualToThreshold treatMissingData: missing functionDuration: namespace: 'AWS/Lambda' metric: Duration threshold: 500 statistic: Average period: 60 evaluationPeriods: 1 comparisonOperator: GreaterThanOrEqualToThreshold treatMissingData: missing functionThrottles: namespace: 'AWS/Lambda' metric: Throttles threshold: 1 statistic: Sum period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanOrEqualToThreshold treatMissingData: missingDefault alarms can be disabled on a per-function basis:
custom: alerts: alarms: - functionThrottles - functionErrors - functionInvocations - functionDuration functions: bar: handler: bar.handler alarms: - name: functionInvocations enabled: false The plugin allows users to provide custom dimensions for the alarm. Dimensions are provided in a list of key/value pairs {Name: foo, Value:bar} The plugin will always apply dimension of {Name: FunctionName, Value: ((FunctionName))}, except if the parameter omitDefaultDimension: true is passed. For example:
alarms: # merged with function alarms - name: fooAlarm namespace: 'AWS/Lambda' metric: errors # define custom metrics here threshold: 1 statistic: Minimum period: 60 evaluationPeriods: 1 comparisonOperator: GreaterThanThreshold omitDefaultDimension: true dimensions: - Name: foo Value: bar'Dimensions': [ { 'Name': 'foo', 'Value': 'bar' }, ]Statistic not only supports SampleCount, Average, Sum, Minimum or Maximum as defined in CloudFormation here, but also percentiles. This is possible by leveraging ExtendedStatistic under the hood. This plugin will automatically choose the correct key for you. See an example below:
definitions: functionDuration: namespace: 'AWS/Lambda' metric: Duration threshold: 100 statistic: 'p95' period: 60 evaluationPeriods: 1 datapointsToAlarm: 1 comparisonOperator: GreaterThanThreshold treatMissingData: missing evaluateLowSampleCountPercentile: ignoreIf your Serverless CloudFormation stack is growing too large and you're running out of resources, you can configure the plugin to deploy a separate stack for the CloudWatch resources. The default behaviour is to create a stack with a "-alerts" suffix in the stack name.
custom: alerts: externalStack: true You can customize the name suffix:
custom: alerts: externalStack: nameSuffix: Alerts The separate stack will be automatically deployed after you've deployed your main Serverless stack. It will also be automatically removed if you remove your main stack.
You can also enable the external stack on the command line with sls deploy --alerts-external-stack which is equivalent to adding externalStack: true to the configuration.
The plugin can create dashboards automatically for basic metrics.
Default setup for a single dashboard:
dashboards: trueCreate a vertical dashboard:
dashboards: verticalCreate dashboards only in specified stages:
dashboards: stages: - production - staging templates: - defaultMIT © A Cloud Guru