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Module: vpc-flow-logs-s3-bucket

Terraform module to create AWS VPC Flow logs backed by S3.

Introduction​

The module will create:

  • S3 bucket with server side encryption
  • KMS key to encrypt flow logs files in the bucket
  • Optional VPC Flow Log backed by the S3 bucket (this can be disabled, e.g. in multi-account environments if you want to create an S3 bucket in one account and VPC Flow Logs in different accounts)

Usage​

For a complete example, see examples/complete.

For automated tests of the complete example using bats and Terratest (which tests and deploys the example on Datadog), see test.

  module "vpc" {
    source  = "cloudposse/vpc/aws"
    version = "0.18.0"

    namespace  = "eg"
    stage      = "test"
    name       = "flowlogs"
    cidr_block = "172.16.0.0/16"
  }

  module "flow_logs" {
    source  = "cloudposse/vpc-flow-logs-s3-bucket/aws"
    version = "0.8.0"

    namespace  = "eg"
    stage      = "test"
    name       = "flowlogs"

    vpc_id = module.vpc.vpc_id
  }

Variables​

Required Variables​

Optional Variables​

access_log_bucket_name (string) optional

Name of the S3 bucket where S3 access log will be sent to


Default value: ""

access_log_bucket_prefix (string) optional

Prefix to prepend to the current S3 bucket name, where S3 access logs will be sent to


Default value: "logs/"

acl (string) optional

The canned ACL to apply. We recommend log-delivery-write for compatibility with AWS services


Default value: "log-delivery-write"

allow_ssl_requests_only (bool) optional

Set to true to require requests to use Secure Socket Layer (HTTPS/SSL). This will explicitly deny access to HTTP requests


Default value: true

bucket_key_enabled (bool) optional

Set this to true to use Amazon S3 Bucket Keys for SSE-KMS, which may reduce the number of AWS KMS requests.
For more information, see: https://docs.aws.amazon.com/AmazonS3/latest/userguide/bucket-key.html



Default value: true

bucket_name (string) optional

Bucket name. If not provided, the bucket will be created with a name generated from the context.



Default value: ""

bucket_notifications_enabled (bool) optional

Send notifications for the object created events. Used for 3rd-party log collection from a bucket


Default value: false

bucket_notifications_prefix (string) optional

Prefix filter. Used to manage object notifications


Default value: ""

bucket_notifications_type (string) optional

Type of the notification configuration. Only SQS is supported.


Default value: "SQS"

expiration_days (number) optional

(Deprecated, use lifecycle_configuration_rules instead)
Number of days after which to expunge the objects


Default value: null

flow_log_enabled (bool) optional

Enable/disable the Flow Log creation. Useful in multi-account environments where the bucket is in one account, but VPC Flow Logs are in different accounts


Default value: true

force_destroy (bool) optional

A boolean that indicates all objects should be deleted from the bucket so that the bucket can be destroyed without error. These objects are not recoverable


Default value: false

glacier_transition_days (number) optional

(Deprecated, use lifecycle_configuration_rules instead)
Number of days after which to move the data to the Glacier Flexible Retrieval storage tier


Default value: null

kms_key_arn (string) optional

ARN (or alias) of KMS that will be used for s3 bucket encryption.


Default value: ""

kms_policy_source_json (string) optional

Additional IAM policy document that can optionally be merged with default created KMS policy


Default value: ""

lifecycle_configuration_rules optional

A list of lifecycle V2 rules


Type:

list(object({
enabled = bool
id      = string

abort_incomplete_multipart_upload_days = number

# `filter_and` is the `and` configuration block inside the `filter` configuration.
# This is the only place you should specify a prefix.
filter_and = optional(object({
  object_size_greater_than = optional(number) # integer >= 0
  object_size_less_than    = optional(number) # integer >= 1
  prefix                   = optional(string)
  tags                     = optional(map(string))
}))
expiration = optional(object({
  date                         = optional(string) # string, RFC3339 time format, GMT
  days                         = optional(number) # integer > 0
  expired_object_delete_marker = optional(bool)
}))
noncurrent_version_expiration = optional(object({
  newer_noncurrent_versions = optional(number) # integer > 0
  noncurrent_days           = optional(number) # integer >= 0
}))
transition = optional(list(object({
  date          = optional(string) # string, RFC3339 time format, GMT
  days          = optional(number) # integer >= 0
  storage_class = string           # string/enum, one of GLACIER, STANDARD_IA, ONEZONE_IA, INTELLIGENT_TIERING, DEEP_ARCHIVE, GLACIER_IR.
})), [])
noncurrent_version_transition = optional(list(object({
  newer_noncurrent_versions = optional(number) # integer >= 0
  noncurrent_days           = optional(number) # integer >= 0
  storage_class             = string           # string/enum, one of GLACIER, STANDARD_IA, ONEZONE_IA, INTELLIGENT_TIERING, DEEP_ARCHIVE, GLACIER_IR.
})), [])
}))

Default value: [ ]

lifecycle_prefix (string) optional

(Deprecated, use lifecycle_configuration_rules instead)
Prefix filter. Used to manage object lifecycle events


Default value: null

lifecycle_rule_enabled (bool) optional

DEPRECATED: Use lifecycle_configuration_rules instead.
When true, configures lifecycle events on this bucket using individual (now deprecated) variables.
When false, lifecycle events are not configured using individual (now deprecated) variables, but lifecycle_configuration_rules still apply.
When null, lifecycle events are configured using individual (now deprecated) variables only if lifecycle_configuration_rules is empty.



Default value: null

lifecycle_tags (map(string)) optional

(Deprecated, use lifecycle_configuration_rules instead)
Tags filter. Used to manage object lifecycle events


Default value: null

log_format (string) optional

The fields to include in the flow log record, in the order in which they should appear.


Default value: null

noncurrent_version_expiration_days (number) optional

(Deprecated, use lifecycle_configuration_rules instead)
Specifies when non-current object versions expire (in days)


Default value: null

noncurrent_version_transition_days (number) optional

(Deprecated, use lifecycle_configuration_rules instead)
Specifies (in days) when noncurrent object versions transition to Glacier Flexible Retrieval


Default value: null

object_lock_configuration optional

A configuration for S3 object locking.



Type:

object({
mode  = string # Valid values are GOVERNANCE and COMPLIANCE.
days  = number
years = number
})

Default value: null

s3_object_ownership (string) optional

Specifies the S3 object ownership control.
Valid values are ObjectWriter, BucketOwnerPreferred, and BucketOwnerEnforced."
Default of BucketOwnerPreferred is for backwards compatibility.
Recommended setting is BucketOwnerEnforced, which will be used if you pass in null.



Default value: "BucketOwnerPreferred"

standard_transition_days (number) optional

(Deprecated, use lifecycle_configuration_rules instead)
Number of days to persist in the standard storage tier before moving to the infrequent access tier


Default value: null

traffic_type (string) optional

The type of traffic to capture. Valid values: ACCEPT, REJECT, ALL


Default value: "ALL"

versioning_enabled (bool) optional

Enable object versioning, keeping multiple variants of an object in the same bucket


Default value: false

vpc_id (string) optional

VPC ID to create flow logs for


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​

bucket_arn

Bucket ARN

bucket_domain_name

FQDN of bucket

bucket_id

Bucket Name (aka ID)

bucket_notifications_sqs_queue_arn

Notifications SQS queue ARN

bucket_prefix

Bucket prefix configured for lifecycle rules

flow_log_arn

Flow Log ARN

flow_log_id

Flow Log ID

kms_alias_arn

KMS Alias ARN

kms_alias_name

KMS Alias name

kms_key_arn

KMS Key ARN

kms_key_id

KMS Key ID

Dependencies​

Requirements​

  • terraform, version: >= 1.3.0
  • aws, version: >= 4.9.0

Providers​

  • aws, version: >= 4.9.0

Modules​

NameVersionSourceDescription
bucket_name0.25.0cloudposse/label/nulln/a
kms_key0.12.2cloudposse/kms-key/awsn/a
s3_log_storage_bucket2.0.0cloudposse/s3-log-storage/awsn/a
this0.25.0cloudposse/label/nulln/a

Resources​

The following resources are used by this module:

Data Sources​

The following data sources are used by this module: