Module: cloudtrail

Terraform module to provision an AWS CloudTrail.

The module accepts an encrypted S3 bucket with versioning to store CloudTrail logs.

The bucket could be from the same AWS account or from a different account.

This is useful if an organization uses a number of separate AWS accounts to isolate the Audit environment from other environments (production, staging, development).

In this case, you create CloudTrail in the production environment (production AWS account), while the S3 bucket to store the CloudTrail logs is created in the Audit AWS account, restricting access to the logs only to the users/groups from the Audit account.

Usage

module "cloudtrail" {
  source = "cloudposse/cloudtrail/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  namespace                     = "eg"
  stage                         = "dev"
  name                          = "cluster"
  enable_log_file_validation    = true
  include_global_service_events = true
  is_multi_region_trail         = false
  enable_logging                = true
  s3_bucket_name                = "my-cloudtrail-logs-bucket"
}

NOTE: To create an S3 bucket for CloudTrail logs, use terraform-aws-cloudtrail-s3-bucket module. It creates an S3 bucket and an IAM policy to allow CloudTrail logs.

module "cloudtrail" {
  source = "cloudposse/cloudtrail/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  namespace                     = "eg"
  stage                         = "dev"
  name                          = "cluster"
  enable_log_file_validation    = true
  include_global_service_events = true
  is_multi_region_trail         = false
  enable_logging                = true
  s3_bucket_name                = module.cloudtrail_s3_bucket.bucket_id
}

module "cloudtrail_s3_bucket" {
  source = "cloudposse/cloudtrail-s3-bucket/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version     = "x.x.x"
  namespace = "eg"
  stage     = "dev"
  name      = "cluster"
}

For a complete example, see examples/complete.

Variables

Required Variables

s3_bucket_name (string) required

S3 bucket name for CloudTrail logs

Optional Variables

advanced_event_selector optional

Specifies an advanced event selector for enabling data event logging. See: https://www.terraform.io/docs/providers/aws/r/cloudtrail.html for details on this variable

Type:

list(object({
name = optional(string)
field_selector = list(object({
  field           = string
  ends_with       = optional(list(string))
  not_ends_with   = optional(list(string))
  equals          = optional(list(string))
  not_equals      = optional(list(string))
  starts_with     = optional(list(string))
  not_starts_with = optional(list(string))
}))
}))

Default value: [ ]

cloud_watch_logs_group_arn (string) optional

Specifies a log group name using an Amazon Resource Name (ARN), that represents the log group to which CloudTrail logs will be delivered

Default value: ""

cloud_watch_logs_role_arn (string) optional

Specifies the role for the CloudWatch Logs endpoint to assume to write to a user’s log group

Default value: ""

enable_log_file_validation (bool) optional

Specifies whether log file integrity validation is enabled. Creates signed digest for validated contents of logs

Default value: true

enable_logging (bool) optional

Enable logging for the trail

Default value: true

event_selector optional

Specifies an event selector for enabling data event logging. See: https://www.terraform.io/docs/providers/aws/r/cloudtrail.html for details on this variable

Type:

list(object({
include_management_events        = bool
read_write_type                  = string
exclude_management_event_sources = optional(set(string))

data_resource = list(object({
  type   = string
  values = list(string)
}))
}))

Default value: [ ]

include_global_service_events (bool) optional

Specifies whether the trail is publishing events from global services such as IAM to the log files

Default value: false

insight_selector optional

Specifies an insight selector for type of insights to log on a trail

Type:

list(object({
insight_type = string
}))

Default value: [ ]

is_multi_region_trail (bool) optional

Specifies whether the trail is created in the current region or in all regions

Default value: true

is_organization_trail (bool) optional

The trail is an AWS Organizations trail

Default value: false

kms_key_arn (string) optional

Specifies the KMS key ARN to use to encrypt the logs delivered by CloudTrail

Default value: ""

s3_key_prefix (string) optional

Prefix for S3 bucket used by Cloudtrail to store logs

Default value: null

sns_topic_name (string) optional

Specifies the name of the Amazon SNS topic defined for notification of log file delivery

Default value: null

Context Variables

The following variables are defined in the context.tf file of this module and part of the terraform-null-label pattern.

additional_tag_map (map(string)) optional

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.

Required: No

Default value: { }

attributes (list(string)) optional

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.

Required: No

Default value: [ ]

context (any) optional

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.

Required: No

Default value:

{
  "additional_tag_map": {},
  "attributes": [],
  "delimiter": null,
  "descriptor_formats": {},
  "enabled": true,
  "environment": null,
  "id_length_limit": null,
  "label_key_case": null,
  "label_order": [],
  "label_value_case": null,
  "labels_as_tags": [
    "unset"
  ],
  "name": null,
  "namespace": null,
  "regex_replace_chars": null,
  "stage": null,
  "tags": {},
  "tenant": null
}

delimiter (string) optional

Delimiter to be used between ID elements.
Defaults to - (hyphen). Set to "" to use no delimiter at all.

Required: No

Default value: null

descriptor_formats (any) optional

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).

Required: No

Default value: { }

enabled (bool) optional

Set to false to prevent the module from creating any resources
Required: No

Default value: null

environment (string) optional

ID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'
Required: No

Default value: null

id_length_limit (number) optional

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.

Required: No

Default value: null

label_key_case (string) optional

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.

Required: No

Default value: null

label_order (list(string)) optional

The order in which the labels (ID elements) appear in the id.
Defaults to ["namespace", "environment", "stage", "name", "attributes"].
You can omit any of the 6 labels ("tenant" is the 6th), but at least one must be present.

Required: No

Default value: null

label_value_case (string) optional

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.

Required: No

Default value: null

labels_as_tags (set(string)) optional

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, not the name.
Unlike other null-label inputs, the initial setting of labels_as_tags cannot be
changed in later chained modules. Attempts to change it will be silently ignored.

Required: No

Default value:

[
  "default"
]

name (string) optional

ID element. Usually the component or solution name, e.g. 'app' or 'jenkins'.
This is the only ID element not also included as a tag.
The "name" tag is set to the full id string. There is no tag with the value of the name input.

Required: No

Default value: null

namespace (string) optional

ID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique
Required: No

Default value: null

regex_replace_chars (string) optional

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.

Required: No

Default value: null

stage (string) optional

ID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'
Required: No

Default value: null

tags (map(string)) optional

Additional tags (e.g. {'BusinessUnit': 'XYZ'}).
Neither the tag keys nor the tag values will be modified by this module.

Required: No

Default value: { }

tenant (string) optional

ID element (Rarely used, not included by default). A customer identifier, indicating who this instance of a resource is for
Required: No

Default value: null

Outputs

cloudtrail_arn

The Amazon Resource Name of the trail

cloudtrail_home_region

The region in which the trail was created

cloudtrail_id

The ID of the trail. (Name for provider < v5, ARN for provider >= v5).

Dependencies

Requirements

• terraform, version: >= 1.3.0
• aws, version: >= 3.0

Providers

• aws, version: >= 3.0

Modules

Name	Version	Source	Description
this	0.25.0	cloudposse/label/null	n/a

Resources

The following resources are used by this module:

• aws_cloudtrail.default (resource)

Data Sources

The following data sources are used by this module: