viget.aws-canary-heartbeat

Terraform module to set up an AWS synthetic canary to conduct heartbeat monitoring of a given endpoint.

Usage

IMPORTANT: We do not pin modules to versions in our examples because of the difficulty of keeping the versions in the documentation in sync with the latest released versions. We highly recommend that in your code you pin the version to the exact version you are using so that your infrastructure remains stable, and update versions in a systematic way so that they do not catch you by surprise.

This module does not set up a notification topic

Simple Monitoring Using Defaults

module "canary" {
  source = "github.com/vigetlabs/terraform-aws-canary-heartbeat.git"

  namespace = "vgt"
  stage     = "example"
  component = "canary"

  attributes = ["monitoring-example"]

  heartbeat_endpoint = "https://www.viget.com"
}

Advanced Monitoring Changing Defaults

module "canary" {
  source = "github.com/vigetlabs/terraform-aws-canary-heartbeat.git"

  namespace = "vgt"
  stage     = "example"
  component = "canary"

  attributes = ["monitoring-example"]

  heartbeat_endpoint        = "https://www.viget.com"
  take_screenshot           = false
  schedule_expression       = "rate(5 minutes)"
  timeout_in_seconds        = 20
  artifacts_expiration_days = 90
}

Cleanup

See DeleteCanary for additional information

Due to AWS and Terraform not always cleaning up all canary resources it may be necessary to locate and manually remove some resources. This module manages the artifacts S3 bucket and IAM roles so terraform destroy will locate and remove them as well as throw the relevant errors for you.

The resources you may need to manually remove will be:

The CloudWatch alarms created for this canary. These alarms have a name of Synthetics-SharpDrop-Alarm-CanaryName
CloudWatch Logs log groups created for the canary. These logs groups have the name /aws/lambda/cwsyn-CanaryName

Before running terraform destroy be sure to take note of the canary_name output.

Requirements

Name	Version
terraform	>= 1.0
aws	>= 4.44.0

Providers

Name	Version
archive	n/a
aws	>= 4.44.0

Resources

Name	Type
aws_iam_policy.logs_policy	resource
aws_iam_policy.metrics_policy	resource
aws_iam_policy.s3_policy	resource
aws_iam_policy.xray_policy	resource
aws_iam_role.this	resource
aws_iam_role_policy_attachment.role_logs	resource
aws_iam_role_policy_attachment.role_metrics	resource
aws_iam_role_policy_attachment.role_s3	resource
aws_iam_role_policy_attachment.role_xray	resource
aws_s3_bucket.artifacts_bucket	resource
aws_s3_bucket_lifecycle_configuration.artifacts_bucket	resource
aws_synthetics_canary.this	resource
archive_file.heartbeat_zip	data source
aws_caller_identity.current	data source
aws_iam_policy_document.assume_role_policy	data source
aws_iam_policy_document.logs_policy	data source
aws_iam_policy_document.metrics_policy	data source
aws_iam_policy_document.s3_policy	data source
aws_iam_policy_document.xray_policy	data source
aws_region.current	data source

Inputs

Name	Description	Type	Default	Required
additional_tag_map	Additional key-value pairs to add to each map in `tags_as_list_of_maps`. Not added to `tags` or `id`. This is for some rare cases where resources want additional configuration of tags and therefore take a list of maps with tag key, value, and additional configuration.	`map(string)`	`{}`	no
artifacts_expiration_days	The number of days to keep artifacts for the canary.	`number`	`30`	no
attributes	ID element. Additional attributes (e.g. `workers` or `cluster`) to add to `id`, in the order they appear in the list. New attributes are appended to the end of the list. The elements of the list are joined by the `delimiter` and treated as a single ID element.	`list(string)`	`[]`	no
component	ID element. Usually the component or solution name, e.g. 'eks', 'rds', 'app'.	`string`	`null`	no
context	Single object for setting entire context at once. See description of individual variables for details. Leave string and numeric variables as `null` to use default value. Individual variable settings (non-null) override settings in context object, except for attributes, tags, and additional_tag_map, which are merged.	`any`	{ "additional_tag_map": {}, "attributes": [], "component": null, "delimiter": null, "descriptor_formats": {}, "enabled": true, "id_length_limit": null, "label_key_case": null, "label_order": [], "label_value_case": null, "labels_as_tags": [ "unset" ], "namespace": null, "regex_replace_chars": null, "tags": {}, "tenant": null }	no
delimiter	Delimiter to be used between ID elements. Defaults to `-` (hyphen). Set to `""` to use no delimiter at all.	`string`	`null`	no
descriptor_formats	Describe additional descriptors to be output in the `descriptors` output map. Map of maps. Keys are names of descriptors. Values are maps of the form `{<br> format = string<br> labels = list(string)<br>}` (Type is `any` so the map values can later be enhanced to provide additional options.) `format` is a Terraform format string to be passed to the `format()` function. `labels` is a list of labels, in order, to pass to `format()` function. Label values will be normalized before being passed to `format()` so they will be identical to how they appear in `id`. Default is `{}` (`descriptors` output will be empty).	`any`	`{}`	no
enabled	Set to false to prevent the module from creating any resources	`bool`	`null`	no
heartbeat_endpoint	The URL for the canary to check if the site is healthy.	`string`	n/a	yes
id_length_limit	Limit `id` to this many characters (minimum 6). Set to `0` for unlimited length. Set to `null` for keep the existing setting, which defaults to `0`. Does not affect `id_full`.	`number`	`null`	no
label_key_case	Controls the letter case of the `tags` keys (label names) for tags generated by this module. Does not affect keys of tags passed in via the `tags` input. Possible values: `lower`, `title`, `upper`. Default value: `title`.	`string`	`null`	no
label_order	The order in which the labels (ID elements) appear in the `id`. Defaults to ["namespace", "stage", "component", "attributes"]. You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present.	`list(string)`	`null`	no
label_value_case	Controls the letter case of ID elements (labels) as included in `id`, set as tag values, and output by this module individually. Does not affect values of tags passed in via the `tags` input. Possible values: `lower`, `title`, `upper` and `none` (no transformation). Set this to `title` and set `delimiter` to `""` to yield Pascal Case IDs. Default value: `lower`.	`string`	`null`	no
labels_as_tags	Set of labels (ID elements) to include as tags in the `tags` output. Default is to include all labels. Tags with empty values will not be included in the `tags` output. Set to `[]` to suppress all generated tags. Notes: The value of the `name` tag, if included, will be the `id`. Unlike other `context` inputs, the initial setting of `labels_as_tags` cannot be changed in later chained modules. Attempts to change it will be silently ignored.	`set(string)`	[ "default" ]	no
namespace	ID element. Usually an abbreviation of the organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique	`string`	`null`	no
regex_replace_chars	Terraform regular expression (regex) string. Characters matching the regex will be removed from the ID elements. If not set, `"/[^a-zA-Z0-9-]/"` is used to remove all characters other than hyphens, letters and digits.	`string`	`null`	no
schedule_expression	The schedule expression for the canary to run see https://registry.terraform.io/providers/hashicorp/aws/latest/docs/resources/synthetics_canary#expression.	`string`	`"rate(15 minutes)"`	no
stage	ID element. Used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'	`string`	`null`	no
tags	Additional tags (e.g. `{'BusinessUnit': 'XYZ'}`). Neither the tag keys nor the tag values will be modified by this module.	`map(string)`	`{}`	no
take_screenshot	Take a screenshot of the response when the canary runs.	`bool`	`true`	no
tenant	ID element _(Rarely used, not included by default)_. A customer identifier, indicating who this instance of a resource is for	`string`	`null`	no
timeout_in_seconds	The timeout in seconds for the canary to run before it must stop.	`number`	`60`	no

Outputs

Name	Description
canary_name	The name of the canary.