Metadata-Version: 2.1
Name: cdk-monitoring-constructs
Version: 10.0.0
Summary: cdk-monitoring-constructs
Home-page: https://github.com/cdklabs/cdk-monitoring-constructs
Author: Amazon Web Services<aws-cdk-dev@amazon.com>
License: Apache-2.0
Project-URL: Source, https://github.com/cdklabs/cdk-monitoring-constructs
Classifier: Intended Audience :: Developers
Classifier: Operating System :: OS Independent
Classifier: Programming Language :: JavaScript
Classifier: Programming Language :: Python :: 3 :: Only
Classifier: Programming Language :: Python :: 3.9
Classifier: Programming Language :: Python :: 3.10
Classifier: Programming Language :: Python :: 3.11
Classifier: Typing :: Typed
Classifier: Development Status :: 4 - Beta
Classifier: License :: OSI Approved
Requires-Python: ~=3.9
Description-Content-Type: text/markdown
License-File: LICENSE
License-File: NOTICE
Requires-Dist: aws-cdk-lib<3.0.0,>=2.160.0
Requires-Dist: constructs<11.0.0,>=10.0.5
Requires-Dist: jsii<2.0.0,>=1.128.0
Requires-Dist: publication>=0.0.3
Requires-Dist: typeguard==2.13.3

# CDK Monitoring Constructs

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Easy-to-use CDK constructs for monitoring your AWS infrastructure with [Amazon CloudWatch](https://aws.amazon.com/cloudwatch/).

* Easily add commonly-used alarms using predefined properties
* Generate concise CloudWatch dashboards that indicate your alarms
* Extend the library with your own extensions or custom metrics
* Consume the library in multiple supported languages

## Installation

<details><summary><strong>TypeScript</strong></summary>

> [https://www.npmjs.com/package/cdk-monitoring-constructs](https://www.npmjs.com/package/cdk-monitoring-constructs)

In your `package.json`:

```json
{
  "dependencies": {
    "cdk-monitoring-constructs": "^9.0.0",

    // peer dependencies of cdk-monitoring-constructs
    "aws-cdk-lib": "^2.160.0",
    "constructs": "^10.0.5"

    // ...your other dependencies...
  }
}
```

</details><details><summary><strong>Java</strong></summary>

See [https://mvnrepository.com/artifact/io.github.cdklabs/cdkmonitoringconstructs](https://mvnrepository.com/artifact/io.github.cdklabs/cdkmonitoringconstructs)

</details><details><summary><strong>Python</strong></summary>

See [https://pypi.org/project/cdk-monitoring-constructs/](https://pypi.org/project/cdk-monitoring-constructs/)

</details><details><summary><strong>C#</strong></summary>

See [https://www.nuget.org/packages/Cdklabs.CdkMonitoringConstructs/](https://www.nuget.org/packages/Cdklabs.CdkMonitoringConstructs/)

</details>

## Features

You can browse the documentation at [https://constructs.dev/packages/cdk-monitoring-constructs/](https://constructs.dev/packages/cdk-monitoring-constructs/)

| Item                                                                                                                                                                                                                 | Monitoring                                                                                   | Alarms                                                                                                     | Notes                                                                                                                                                                                                                                                                                           |
| -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| AWS API Gateway (REST API) (`.monitorApiGateway()`)                                                                                                                                                                  | TPS, latency, errors                                                                         | Latency, error count/rate, low/high TPS                                                                    | To see metrics, you have to enable Advanced Monitoring                                                                                                                                                                                                                                          |
| AWS API Gateway V2 (HTTP API) (`.monitorApiGatewayV2HttpApi()`)                                                                                                                                                      | TPS, latency, errors                                                                         | Latency, error count/rate, low/high TPS                                                                    | To see route level metrics, you have to enable Advanced Monitoring                                                                                                                                                                                                                              |
| AWS AppSync (GraphQL API) (`.monitorAppSyncApi()`)                                                                                                                                                                   | TPS, latency, errors                                                                         | Latency, error count/rate, low/high TPS                                                                    |                                                                                                                                                                                                                                                                                                 |
| Amazon Aurora (`.monitorAuroraCluster()`)                                                                                                                                                                            | Query duration, connections, latency, CPU usage, Serverless Database Capacity                | Connections, Serverless Database Capacity and CPU usage                                                    |                                                                                                                                                                                                                                                                                                 |
| AWS Billing (`.monitorBilling()`)                                                                                                                                                                                    | AWS account cost                                                                             | Total cost (anomaly)                                                                                       | [Requires enabling](https://docs.aws.amazon.com/AmazonCloudWatch/latest/monitoring/gs_monitor_estimated_charges_with_cloudwatch.html#gs_turning_on_billing_metrics) the **Receive Billing Alerts** option in AWS Console / Billing Preferences                                                  |
| AWS Certificate Manager (`.monitorCertificate()`)                                                                                                                                                                    | Certificate expiration                                                                       | Days until expiration                                                                                      |                                                                                                                                                                                                                                                                                                 |
| AWS CloudFront (`.monitorCloudFrontDistribution()`)                                                                                                                                                                  | TPS, traffic, latency, errors                                                                | Error rate, low/high TPS                                                                                   |                                                                                                                                                                                                                                                                                                 |
| AWS CloudWatch Logs (`.monitorLog()`)                                                                                                                                                                                | Patterns present in the log group                                                            | Minimum incoming logs                                                                                      |                                                                                                                                                                                                                                                                                                 |
| AWS CloudWatch Synthetics Canary (`.monitorSyntheticsCanary()`)                                                                                                                                                      | Latency, error count/rate                                                                    | Error count/rate, latency                                                                                  |                                                                                                                                                                                                                                                                                                 |
| AWS CodeBuild (`.monitorCodeBuildProject()`)                                                                                                                                                                         | Build counts (total, successful, failed), failed rate, duration                              | Failed build count/rate, duration                                                                          |                                                                                                                                                                                                                                                                                                 |
| AWS DocumentDB (`.monitorDocumentDbCluster()`)                                                                                                                                                                       | CPU, throttling, read/write latency, transactions, cursors                                   | CPU                                                                                                        |                                                                                                                                                                                                                                                                                                 |
| AWS DynamoDB (`.monitorDynamoTable()`)                                                                                                                                                                               | Read and write capacity provisioned / used                                                   | Consumed capacity, throttling, latency, errors                                                             |                                                                                                                                                                                                                                                                                                 |
| AWS DynamoDB Global Secondary Index (`.monitorDynamoTableGlobalSecondaryIndex()`)                                                                                                                                    | Read and write capacity, indexing progress, throttled events                                 |                                                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS EC2 (`.monitorEC2Instances()`)                                                                                                                                                                                   | CPU, disk operations, network                                                                |                                                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS EC2 Auto Scaling Groups (`.monitorAutoScalingGroup()`)                                                                                                                                                           | Group size, instance status                                                                  |                                                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS ECS (`.monitorFargateService()`, `.monitorEc2Service()`, `.monitorSimpleFargateService()`, `monitorSimpleEc2Service()`, `.monitorQueueProcessingFargateService()`, `.monitorQueueProcessingEc2Service()`)        | System resources and task health                                                             | Unhealthy task count, running tasks count, CPU/memory usage, and bytes processed by load balancer (if any) | Use for ecs-patterns load balanced ec2/fargate constructs (NetworkLoadBalancedEc2Service, NetworkLoadBalancedFargateService, ApplicationLoadBalancedEc2Service, ApplicationLoadBalancedFargateService)                                                                                          |
| AWS ElastiCache (`.monitorElastiCacheCluster()`)                                                                                                                                                                     | CPU/memory usage, evictions and connections                                                  | CPU, memory, items count                                                                                   |                                                                                                                                                                                                                                                                                                 |
| AWS Glue (`.monitorGlueJob()`)                                                                                                                                                                                       | Traffic, job status, memory/CPU usage                                                        | Failed/killed task count/rate                                                                              |                                                                                                                                                                                                                                                                                                 |
| AWS Kinesis Data Analytics (`.monitorKinesisDataAnalytics`)                                                                                                                                                          | Up/Downtime, CPU/memory usage, KPU usage, checkpoint metrics, and garbage collection metrics | Downtime, full restart count                                                                               |                                                                                                                                                                                                                                                                                                 |
| AWS Kinesis Data Stream (`.monitorKinesisDataStream()`)                                                                                                                                                              | Put/Get/Incoming Record/s and Throttling                                                     | Throttling, throughput, iterator max age                                                                   |                                                                                                                                                                                                                                                                                                 |
| AWS Kinesis Firehose (`.monitorKinesisFirehose()`)                                                                                                                                                                   | Number of records, requests, latency, throttling                                             | Throttling                                                                                                 |                                                                                                                                                                                                                                                                                                 |
| AWS Lambda (`.monitorLambdaFunction()`)                                                                                                                                                                              | Latency, errors, iterator max age                                                            | Latency, errors, throttles, iterator max age                                                               | Optional Lambda Insights metrics (opt-in) support                                                                                                                                                                                                                                               |
| AWS Load Balancing (`.monitorNetworkLoadBalancer()`, `.monitorFargateApplicationLoadBalancer()`, `.monitorFargateNetworkLoadBalancer()`, `.monitorEc2ApplicationLoadBalancer()`, `.monitorEc2NetworkLoadBalancer()`) | System resources and task health                                                             | Unhealthy task count, running tasks count, (for Fargate/Ec2 apps) CPU/memory usage                         | Use for FargateService or Ec2Service backed by a NetworkLoadBalancer or ApplicationLoadBalancer                                                                                                                                                                                                 |
| AWS OpenSearch/Elasticsearch (`.monitorOpenSearchCluster()`, `.monitorElasticsearchCluster()`)                                                                                                                       | Indexing and search latency, disk/memory/CPU usage                                           | Indexing and search latency, disk/memory/CPU usage, cluster status, KMS keys                               |                                                                                                                                                                                                                                                                                                 |
| AWS OpenSearch Ingestion (`.monitorOpenSearchIngestionPipeline()`)                                                                                                                                                   | Latency, incoming data, DLQ records count                                                    | DLQ records count                                                                                          |                                                                                                                                                                                                                                                                                                 |
| AWS OpenSearch Serverless (`.monitorOpenSearchServerlessCollection()`)                                                                                                                                               | Search latency, errors, ingestion requests/latency                                           | Search latency, errors                                                                                     |                                                                                                                                                                                                                                                                                                 |
| AWS OpenSearch Serverless (`.monitorOpenSearchServerlessIndex()`)                                                                                                                                                    | Documents count                                                                              |                                                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS RDS (`.monitorRdsCluster()`)                                                                                                                                                                                     | Query duration, connections, latency, disk/CPU usage                                         | Connections, disk and CPU usage                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS RDS (`.monitorRdsInstance()`)                                                                                                                                                                                    | Query duration, connections, latency, disk/CPU usage                                         | Connections, disk and CPU usage                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS Redshift (`.monitorRedshiftCluster()`)                                                                                                                                                                           | Query duration, connections, latency, disk/CPU usage                                         | Query duration, connections, disk and CPU usage                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS S3 Bucket (`.monitorS3Bucket()`)                                                                                                                                                                                 | Bucket size and number of objects                                                            |                                                                                                            |                                                                                                                                                                                                                                                                                                 |
| AWS SecretsManager (`.monitorSecretsManager()`)                                                                                                                                                                      | Max secret count, min secret sount, secret count change                                      | Min/max secret count or change in secret count                                                             |                                                                                                                                                                                                                                                                                                 |
| AWS SecretsManager Secret (`.monitorSecretsManagerSecret()`)                                                                                                                                                         | Days since last rotation                                                                     | Days since last change or rotation                                                                         |                                                                                                                                                                                                                                                                                                 |
| AWS SNS Topic (`.monitorSnsTopic()`)                                                                                                                                                                                 | Message count, size, failed notifications                                                    | Failed notifications, min/max published messages                                                           |                                                                                                                                                                                                                                                                                                 |
| AWS SQS Queue (`.monitorSqsQueue()`, `.monitorSqsQueueWithDlq()`)                                                                                                                                                    | Message count, age, size                                                                     | Message count, age, DLQ incoming messages                                                                  |                                                                                                                                                                                                                                                                                                 |
| AWS Step Functions (`.monitorStepFunction()`, `.monitorStepFunctionActivity()`, `monitorStepFunctionLambdaIntegration()`, `.monitorStepFunctionServiceIntegration()`)                                                | Execution count and breakdown per state                                                      | Duration, failed, failed rate, aborted, throttled, timed out executions                                    |                                                                                                                                                                                                                                                                                                 |
| AWS Web Application Firewall (`.monitorWebApplicationFirewallAclV2()`)                                                                                                                                               | Allowed/blocked requests                                                                     | Blocked requests count/rate                                                                                |                                                                                                                                                                                                                                                                                                 |
| FluentBit (`.monitorFluentBit()`)                                                                                                                                                                                    | Num of input records, Output failures & retries, Filter metrics, Storage metrics             |                                                                                                            | FluentBit needs proper configuration with metrics enabled: [Official sample configuration](https://github.com/aws-samples/amazon-ecs-firelens-examples/tree/mainline/examples/fluent-bit/send-fb-internal-metrics-to-cw). This function creates MetricFilters to publish all FluentBit metrics. |
| Custom metrics (`.monitorCustom()`)                                                                                                                                                                                  | Addition of custom metrics into the dashboard (each group is a widget)                       |                                                                                                            | Supports anomaly detection                                                                                                                                                                                                                                                                      |

## Getting started

### Create a facade

*Important note*: **Please, do NOT import anything from the `/dist/lib` package.** This is unsupported and might break any time.

1. Create an instance of `MonitoringFacade`, which is the main entrypoint.
2. Call methods on the facade like `.monitorLambdaFunction()` and chain them together to define your monitors. You can also use methods to add your own widgets, headers of various sizes, and more.

For examples of monitoring different resources, refer to [the unit tests](https://github.com/cdklabs/cdk-monitoring-constructs/tree/main/test/monitoring).

```python
# Example automatically generated from non-compiling source. May contain errors.
# This could be in the same stack as your resources, as a nested stack, or a separate stack as you see fit
class MonitoringStack(DeploymentStack):
    def __init__(self, parent, name, *):
        super().__init__(parent, name)

        monitoring = MonitoringFacade(self, "Monitoring",
            # Defaults are provided for these, but they can be customized as desired
            metric_factory_defaults={...},
            alarm_factory_defaults={...},
            dashboard_factory={...}
        )

        # Monitor your resources
        monitoring.add_large_header("Storage").monitor_dynamo_table().monitor_dynamo_table().monitor_lambda_function().monitor_custom()
```

### Customize actions

Alarms should have actions set up, otherwise they are not very useful.

Example of notifying an SNS topic:

```python
# Example automatically generated from non-compiling source. May contain errors.
# on_alarm_topic: ITopic

monitoring = MonitoringFacade(self, "Monitoring",
    # ...other props
    alarm_factory_defaults={
        # ....other props
        "action": SnsAlarmActionStrategy(on_alarm_topic=on_alarm_topic)
    }
)
```

You can override the default topic for any alarm like this:

```python
# Example automatically generated from non-compiling source. May contain errors.
monitoring.monitor_something(something,
    add_some_alarm={
        "Warning": {
            # ...other props
            "threshold": 42,
            "action_override": SnsAlarmActionStrategy(on_alarm_topic=on_alarm_topic)
        }
    }
)
```

Supported actions can be found [here](https://github.com/cdklabs/cdk-monitoring-constructs/tree/main/lib/common/alarm/action), including SNS and Lambda.

You can also compose multiple actions using `multipleActions`:

```python
# Example automatically generated from non-compiling source. May contain errors.
# on_alarm_topic: ITopic
# on_alarm_function: IFunction

action = multiple_actions(
    notify_sns(on_alarm_topic),
    trigger_lambda(on_alarm_function))
```

### Custom metrics

For simply adding some custom metrics, you can use `.monitorCustom()` and specify your own title and metric groups.
Each metric group will be rendered as a single graph widget, and all widgets will be placed next to each other.
All the widgets will have the same size, which is chosen based on the number of groups to maximize dashboard space usage.

Custom metric monitoring can be created for simple metrics, simple metrics with anomaly detection and search metrics.
The first two also support alarming.

Below we are listing a couple of examples. Let us assume that there are three existing metric variables: `m1`, `m2`, `m3`.
They can either be created by hand (`new Metric({...})`) or (preferably) by using `metricFactory` (that can be obtained from facade).
The advantage of using the shared `metricFactory` is that you do not need to worry about period, etc.

```python
# Example automatically generated from non-compiling source. May contain errors.
# create metrics manually
m1 = Metric()
```

```python
# Example automatically generated from non-compiling source. May contain errors.
metric_factory = monitoring_facade.create_metric_factory()

# create metrics using metric factory
m1 = metric_factory.create_metric()
```

#### Example: metric with anomaly detection

In this case, only one metric is supported.
Multiple metrics cannot be rendered with anomaly detection in a single widget due to a CloudWatch limitation.

```python
monitor_custom({
    "title": "Metric with anomaly detection",
    "metric_groups": [{
        "metric": m1,
        "anomaly_detection_standard_deviation_to_render": 3
    }
    ]
})
```

Adding an alarm:

```python
monitor_custom({
    "title": "Metric with anomaly detection and alarm",
    "metric_groups": [{
        "metric": m1,
        "alarm_friendly_name": "MetricWithAnomalyDetectionAlarm",
        "anomaly_detection_standard_deviation_to_render": 3,
        "add_alarm_on_anomaly": {
            "Warning": {
                "standard_deviation_for_alarm": 4,
                "alarm_when_above_the_band": True,
                "alarm_when_below_the_band": True
            }
        }
    }
    ]
})
```

#### Example: search metrics

```python
monitor_custom({
    "title": "Metric search",
    "metric_groups": [{
        "search_query": "My.Prefix.",
        "dimensions_map": {
            "FirstDimension": "FirstDimensionValue",
            # Allow any value for the given dimension (pardon the weird typing to satisfy DimensionsMap)
            "SecondDimension": undefined
        },
        "statistic": MetricStatistic.SUM
    }
    ]
})
```

Search metrics do not support setting an alarm, which is a CloudWatch limitation.

### Route53 Health Checks

Route53 has [strict requirements](https://docs.aws.amazon.com/Route53/latest/DeveloperGuide/health-checks-types.html) as to which alarms are allowed to be referenced in Health Checks.
You adjust the metric for an alarm so that it can be used in a Route53 Health Checks as follows:

```python
monitoring.monitor_something(something,
    add_some_alarm={
        "Warning": {
            # ...other props
            "metric_adjuster": Route53HealthCheckMetricAdjuster.INSTANCE
        }
    }
)
```

This will ensure the alarm can be used on a Route53 Health Check or otherwise throw an `Error` indicating why the alarm can't be used.
In order to easily find your Route53 Health Check alarms later on, you can apply a custom tag to them as follows:

```python
# Example automatically generated from non-compiling source. May contain errors.
from aws_cdk.aws_route53 import CfnHealthCheck

monitoring.monitor_something(something,
    add_some_alarm={
        "Warning": {
            # ...other props
            "custom_tags": ["route53-health-check"],
            "metric_adjuster": Route53HealthCheckMetricAdjuster.INSTANCE
        }
    }
)

alarms = monitoring.created_alarms_with_tag("route53-health-check")

health_checks = alarms.map(({ alarm }) => {
      const id = getHealthCheckConstructId(alarm);

      return new CfnHealthCheck(scope, id, {
        healthCheckConfig: {
          // ...other props
          type: "CLOUDWATCH_METRIC",
          alarmIdentifier: {
            name: alarm.alarmName,
            region: alarm.stack.region,
          },
        },
      });
    })
```

### Custom monitoring segments

If you want even more flexibility, you can create your own segment.

This is a general procedure on how to do it:

1. Extend the `Monitoring` class
2. Override the `widgets()` method (and/or similar ones)
3. Leverage the metric factory and alarm factory provided by the base class (you can create additional factories, if you will)
4. Add all alarms to `.addAlarm()` so they are visible to the user and being placed on the alarm summary dashboard

Both of these monitoring base classes are dashboard segments, so you can add them to your monitoring by calling `.addSegment()` on the `MonitoringFacade`.

### Modifying or omitting widgets from default dashboard segments

While the dashboard widgets defined in the library are meant to cover most use cases, they might not be what you're looking for.

To modify the widgets:

1. Extend the appropriate `Monitoring` class (e.g., `LambdaFunctionMonitoring` for `monitorLambdaFunction`) and override the relevant methods (e.g., `widgets`):

   ```python
   # Example automatically generated from non-compiling source. May contain errors.
   class MyCustomizedLambdaFunctionMonitoring(LambdaFunctionMonitoring):
       def widgets(self):
           return []
   ```
2. Use the facade's `addSegment` method with your custom class:

   ```python
   # Example automatically generated from non-compiling source. May contain errors.
   # facade: MonitoringFacade

   facade.add_segment(
       MyCustomizedLambdaFunctionMonitoring(facade))
   ```

### Custom dashboards

If you want *even* more flexibility, you can take complete control over dashboard generation by leveraging dynamic dashboarding features. This allows you to create an arbitrary number of dashboards while configuring each of them separately. You can do this in three simple steps:

1. Create a dynamic dashboard factory
2. Create `IDynamicDashboardSegment` implementations
3. Add Dynamic Segments to your `MonitoringFacade`

#### Create a dynamic dashboard factory

The below code sample will generate two dashboards with the following names:

* ExampleDashboards-HostedService
* ExampleDashboards-Infrastructure

```python
# Example automatically generated from non-compiling source. May contain errors.
# create the dynamic dashboard factory.
factory = DynamicDashboardFactory(stack, "DynamicDashboards",
    dashboard_name_prefix="ExampleDashboards",
    dashboard_configs=[{"name": "HostedService"}, {
        "name": "Infrastructure",
        "range": Duration.hours(3),
        "period_override": PeriodOverride.AUTO,
        "rendering_preference": DashboardRenderingPreference.BITMAP_ONLY
    }
    ]
)
```

#### Create `IDynamicDashboardSegment` implementations

For each construct you want monitored, you will need to create an implementation of an `IDynamicDashboardSegment`. The following is a basic reference implementation as an example:

```python
# Example automatically generated from non-compiling source. May contain errors.
export enum DashboardTypes {
  HostedService = "HostedService",
  Infrastructure = "Infrastructure",
}

class ExampleSegment(IDynamicDashboardSegment):
    def widgets_for_dashboard(self, name): switch (name) {
              case DashboardTypes.HostedService:
                return [
                  new TextWidget({
                    markdown:
                      "This shows metrics for your service hosted on AWS Infrastructure",
                  }),
                ];
              case DashboardTypes.Infrastructure:
                return [
                  new TextWidget({
                    markdown:
                      "This shows metrics for the AWS Infrastructure supporting your hosted service",
                  }),
                ];
              default:
                throw new Error("Unexpected dashboard name!");
            }
```

#### Add Dynamic Segments to MonitoringFacade

When you have instances of an `IDynamicDashboardSegment` to use, they can be added to your dashboard like this:

```python
# Example automatically generated from non-compiling source. May contain errors.
monitoring.add_dynamic_segment(ExampleSegment())
```

Now, this widget will be added to both dashboards and will show different content depending on the dashboard. Using the above example code, two dashboards will be generated with the following content:

* Dashboard Name: "ExampleDashboards-HostedService"

  * Content: "This shows metrics for your service hosted on AWS Infrastructure"
* Dashboard Name: "ExampleDashboards-Infrastructure"

  * Content: "This shows metrics for the AWS Infrastructure supporting your hosted service"

### Cross-account cross-Region Dashboards

Facades can be configured for different regions/accounts as a whole:

```python
from cdk_monitoring_constructs import MetricFactoryDefaults
MonitoringFacade(stack, "Monitoring",
    metric_factory_defaults=MetricFactoryDefaults(
        # Different region/account than what you're deploying to
        region="us-west-2",
        account="01234567890"
    )
)
```

Or at a more granular level:

```python
monitoring.monitor_dynamo_table(
    # Table from the same account/region
    table=Table.from_table_name(stack, "ImportedTable", "MyTableName")
).monitor_dynamo_table(
    # Table from another account/region
    table=Table.from_table_arn(stack, "XaXrImportedTable", "arn:aws:dynamodb:us-west-2:01234567890:table/my-other-table"),
    region="us-west-2",
    account="01234567890"
)
```

The order of precedence of the region/account values is:

1. The individual metric factory's props (e.g. via the `monitorDynamoTable` props).
2. The facade's `metricFactoryDefaults` props.
3. The region/account that the stack is deployed to.

Note that while this allows for cross-account cross-Region dashboarding, cross-Region alarming is not supported by CloudWatch.

### Monitoring scopes

You can monitor complete CDK construct scopes using an aspect. It will automatically discover all monitorable resources within the scope recursively and add them to your dashboard.

```python
monitoring.monitor_scope(stack,
    # With optional configuration
    lambda_={
        "props": {
            "add_latency_p50_alarm": {
                "Critical": {"max_latency": Duration.seconds(10)}
            }
        }
    },

    # Some resources that aren't dependent on nodes (e.g. general metrics across instances/account) may be included
    # by default, which can be explicitly disabled.
    billing={"enabled": False},
    ec2={"enabled": False},
    elastic_cache={"enabled": False}
)
```

### Cloning alarms

You can also create alarms by cloning other alarms and applying a modification function.
When given a list of alarms created using `MonitoringFacade`, the facade can apply a
user-supplied function on each, generating new alarms with customizations from the
function.

```python
# Example automatically generated from non-compiling source. May contain errors.
# Clone alarms using a cloning-function
critical_alarms = monitoring.created_alarms_with_disambiguator("Critical")
clones = monitoring.clone_alarms(critical_alarms, (a) => {
      // Define a new alarm that has values inspired by the original alarm
      // Adjust some of those values using arbitrary, user-provided logic
      return {
        ...a.alarmDefinition.addAlarmProps,
        actionsEnabled: false,
        disambiguator: "ClonedCritical",
        alarmDescription: "Cloned alarm of " + a.alarmDescription,
        // Bump the threshold a bit
        threshold: a.alarmDefinition.addAlarmProps.threshold * 1.1,
        // Tighten the number of datapoints a bit
        datapointsToAlarm: a.alarmDefinition.datapointsToAlarm - 1,
        // Keep the same number of evaluation periods
        evaluationPeriods: a.alarmDefinition.evaluationPeriods,
      };
    })
```

This technique is particularly useful when you are using alarms for multiple purposes.
For instance, you may want to ensure regressions that result in an SLA-breach are
automatically rolled back *before* a ticketing action takes effect. This scheme uses
pairs of alarms for each metric: a conservative ticketing alarm and an aggressive
rollback alarm.

Rather that specifying both alarms throughout your application, you can automatically
create the companion alarms by cloning with a scaling function. This library provides a
`ScaleFunction` implementation that can be configured with multiplication factors for
`threshold`, `datapointsToAlarm`, and `evaluationPeriods`; scaling factors between 0.0
and 1.0 will generate more aggressive alarms.

```python
# Clone critical alarms using a tighting scaling function
critical_alarms = monitoring.created_alarms_with_disambiguator("Critical")
rollback_alarms = monitoring.clone_alarms(critical_alarms,
    ScaleAlarms(
        disambiguator="Rollback",
        threshold_multiplier=0.8,
        datapoints_to_alarm_multiplier=0.3,
        evaluation_periods_multiplier=0.5
    ))
```

## Contributing

See [CONTRIBUTING](CONTRIBUTING.md) for more information.

## Security policy

See [SECURITY](SECURITY.md) for more information.

## License

This project is licensed under the Apache-2.0 License.
