Module: `alb`

Terraform module to create an ALB, default ALB listener(s), and a default ALB target and related security groups.

Usage

For a complete example, see examples/complete.

For automated test of the complete example using bats and Terratest, see test.

provider "aws" {
  region = var.region
}

module "vpc" {
  source  = "cloudposse/vpc/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version = "x.x.x"

  namespace  = var.namespace
  stage      = var.stage
  name       = var.name
  delimiter  = var.delimiter
  attributes = var.attributes

  ipv4_primary_cidr_block = "10.0.0.0/16"
  assign_generated_ipv6_cidr_block = true

  tags = var.tags
}

module "subnets" {
  source  = "cloudposse/dynamic-subnets/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version = "x.x.x"

  namespace  = var.namespace
  stage      = var.stage
  name       = var.name
  attributes = var.attributes
  delimiter  = var.delimiter

  availability_zones   = var.availability_zones
  vpc_id               = module.vpc.vpc_id
  igw_id               = module.vpc.igw_id
  cidr_block           = module.vpc.vpc_cidr_block
  nat_gateway_enabled  = false
  nat_instance_enabled = false

  tags = var.tags
}

module "alb" {
  source = "cloudposse/alb/aws"
  # Cloud Posse recommends pinning every module to a specific version
  # version = "x.x.x"

  namespace  = var.namespace
  stage      = var.stage
  name       = var.name
  attributes = var.attributes
  delimiter  = var.delimiter

  vpc_id                                  = module.vpc.vpc_id
  security_group_ids                      = [module.vpc.vpc_default_security_group_id]
  subnet_ids                              = module.subnets.public_subnet_ids
  internal                                = var.internal
  http_enabled                            = var.http_enabled
  http_redirect                           = var.http_redirect
  access_logs_enabled                     = var.access_logs_enabled
  cross_zone_load_balancing_enabled       = var.cross_zone_load_balancing_enabled
  http2_enabled                           = var.http2_enabled
  idle_timeout                            = var.idle_timeout
  ip_address_type                         = var.ip_address_type
  deletion_protection_enabled             = var.deletion_protection_enabled
  deregistration_delay                    = var.deregistration_delay
  health_check_path                       = var.health_check_path
  health_check_timeout                    = var.health_check_timeout
  health_check_healthy_threshold          = var.health_check_healthy_threshold
  health_check_unhealthy_threshold        = var.health_check_unhealthy_threshold
  health_check_interval                   = var.health_check_interval
  health_check_matcher                    = var.health_check_matcher
  target_group_port                       = var.target_group_port
  target_group_target_type                = var.target_group_target_type
  stickiness                              = var.stickiness

  alb_access_logs_s3_bucket_force_destroy         = var.alb_access_logs_s3_bucket_force_destroy
  alb_access_logs_s3_bucket_force_destroy_enabled = var.alb_access_logs_s3_bucket_force_destroy_enabled

  tags = var.tags
}

Variables

Required Variables

subnet_ids (list(string)) required: A list of subnet IDs to associate with ALB
vpc_id (string) required: VPC ID to associate with ALB

Optional Variables

access_logs_enabled (bool) optional

A boolean flag to enable/disable access_logs

Default value: true

access_logs_prefix (string) optional

The S3 log bucket prefix

Default value: ""

access_logs_s3_bucket_id (string) optional

An external S3 Bucket name to store access logs in. If specified, no logging bucket will be created.

Default value: null

additional_certs (list(string)) optional

A list of additonal certs to add to the https listerner

Default value: [ ]

alb_access_logs_s3_bucket_force_destroy (bool) optional

A boolean that indicates all objects should be deleted from the ALB access logs S3 bucket so that the bucket can be destroyed without error

Default value: false

allow_ssl_requests_only (bool) optional

Set to true to require requests to use Secure Socket Layer (HTTPS/SSL) on the access logs S3 bucket. This will explicitly deny access to HTTP requests

Default value: false

certificate_arn (string) optional

The ARN of the default SSL certificate for HTTPS listener

Default value: ""

client_keep_alive (number) optional

Client keep alive value in seconds. The valid range is 60-604800 seconds. The default is 3600 seconds.

Default value: 3600

cross_zone_load_balancing_enabled (bool) optional

A boolean flag to enable/disable cross zone load balancing

Default value: true

default_target_group_enabled (bool) optional

Whether the default target group should be created or not.

Default value: true

deletion_protection_enabled (bool) optional

A boolean flag to enable/disable deletion protection for ALB

Default value: false

deregistration_delay (number) optional

The amount of time to wait in seconds before changing the state of a deregistering target to unused

Default value: 15

drop_invalid_header_fields (bool) optional

Indicates whether HTTP headers with header fields that are not valid are removed by the load balancer (true) or routed to targets (false).

Default value: false

enable_glacier_transition (bool) optional

(Deprecated, use lifecycle_configuration_rules instead)
Enables the transition to AWS Glacier which can cause unnecessary costs for huge amount of small files

Default value: true

expiration_days (number) optional

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

Default value: 90

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: 60

health_check_healthy_threshold (number) optional

The number of consecutive health checks successes required before considering an unhealthy target healthy

Default value: 2

health_check_interval (number) optional

The duration in seconds in between health checks

Default value: 15

health_check_matcher (string) optional

The HTTP response codes to indicate a healthy check

Default value: "200-399"

health_check_path (string) optional

The destination for the health check request

Default value: "/"

health_check_port (string) optional

The port to use for the healthcheck

Default value: "traffic-port"

health_check_protocol (string) optional

The protocol to use for the healthcheck. If not specified, same as the traffic protocol

Default value: null

health_check_timeout (number) optional

The amount of time to wait in seconds before failing a health check request

Default value: 10

health_check_unhealthy_threshold (number) optional

The number of consecutive health check failures required before considering the target unhealthy

Default value: 2

http2_enabled (bool) optional

A boolean flag to enable/disable HTTP/2

Default value: true

http_enabled (bool) optional

A boolean flag to enable/disable HTTP listener

Default value: true

http_ingress_cidr_blocks (list(string)) optional

List of CIDR blocks to allow in HTTP security group

Default value:

[
  "0.0.0.0/0",
  "::/0"
]

http_ingress_prefix_list_ids (list(string)) optional

List of prefix list IDs for allowing access to HTTP ingress security group

Default value: [ ]

http_port (number) optional

The port for the HTTP listener

Default value: 80

http_redirect (bool) optional

A boolean flag to enable/disable HTTP redirect to HTTPS

Default value: false

https_enabled (bool) optional

A boolean flag to enable/disable HTTPS listener

Default value: false

https_ingress_cidr_blocks (list(string)) optional

List of CIDR blocks to allow in HTTPS security group

Default value:

[
  "0.0.0.0/0",
  "::/0"
]

https_ingress_prefix_list_ids (list(string)) optional

List of prefix list IDs for allowing access to HTTPS ingress security group

Default value: [ ]

https_port (number) optional

The port for the HTTPS listener

Default value: 443

https_ssl_policy (string) optional

The name of the SSL Policy for the listener

Default value: "ELBSecurityPolicy-TLS13-1-2-2021-06"

idle_timeout (number) optional

The time in seconds that the connection is allowed to be idle

Default value: 60

internal (bool) optional

A boolean flag to determine whether the ALB should be internal

Default value: false

ip_address_type (string) optional

The type of IP addresses used by the subnets for your load balancer. The possible values are ipv4 and dualstack.

Default value: "ipv4"

lifecycle_configuration_rules optional

A list of S3 bucket v2 lifecycle rules, as specified in terraform-aws-s3-bucket"
These rules are not affected by the deprecated lifecycle_rule_enabled flag.
NOTE: Unless you also set lifecycle_rule_enabled = false you will also get the default deprecated rules set on your bucket.

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 = any
expiration = any
transition = list(any)

noncurrent_version_expiration = any
noncurrent_version_transition = list(any)
}))

Default value: [ ]

lifecycle_rule_enabled (bool) optional

DEPRECATED: Defaults to false, use lifecycle_configuration_rules instead.
When true, configures lifecycle events on this bucket using individual (now deprecated) variables."

Default value: false

listener_additional_tags (map(string)) optional

The additional tags to apply to all listeners

Default value: { }

listener_http_fixed_response optional

Have the HTTP listener return a fixed response for the default action.

Type:

object({
content_type = string
message_body = string
status_code  = string
})

Default value: null

listener_https_fixed_response optional

Have the HTTPS listener return a fixed response for the default action.

Type:

object({
content_type = string
message_body = string
status_code  = string
})

Default value: null

listener_https_redirect optional

Have the HTTPS listener return a redirect response for the default action.

Type:

object({
host        = optional(string)
path        = optional(string)
port        = optional(string)
protocol    = optional(string)
query       = optional(string)
status_code = string
})

Default value: null

load_balancer_name (string) optional

The name for the default load balancer, uses a module label name if left empty

Default value: ""

load_balancer_name_max_length (number) optional

The max length of characters for the load balancer.

Default value: 32

load_balancing_algorithm_type (string) optional

Determines how the load balancer selects targets when routing requests. Only applicable for Application Load Balancer Target Groups

Default value: "round_robin"

load_balancing_anomaly_mitigation (string) optional

Determines whether to enable target anomaly mitigation. Only supported by the weighted_random load balancing algorithm type. Valid values are 'on' or 'off'.

Default value: "off"

noncurrent_version_expiration_days (number) optional

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

Default value: 90

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: 30

preserve_host_header (bool) optional

Indicates whether the Application Load Balancer should preserve the Host header in the HTTP request and send it to the target without any change.

Default value: false

security_group_enabled (bool) optional

Enables the security group

Default value: true

security_group_ids (list(string)) optional

A list of additional security group IDs to allow access to ALB

Default value: [ ]

slow_start (number) optional

The amount of time (30-900 seconds) until a healthy target receives its full share of requests from the load balancer. 0 to disable.

Default value: null

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: 30

stickiness optional

Target group sticky configuration

Type:

object({
cookie_duration = number
enabled         = bool
})

Default value: null

target_group_additional_tags (map(string)) optional

The additional tags to apply to the target group

Default value: { }

target_group_name (string) optional

The name for the default target group, uses a module label name if left empty

Default value: ""

target_group_name_max_length (number) optional

The max length of characters for the target group.

Default value: 32

target_group_port (number) optional

The port for the default target group

Default value: 80

target_group_protocol (string) optional

The protocol for the default target group HTTP or HTTPS

Default value: "HTTP"

target_group_protocol_version (string) optional

The protocol version for the default target group HTTP1 or HTTP2 or GRPC

Default value: "HTTP1"

target_group_target_type (string) optional

The type (instance, ip or lambda) of targets that can be registered with the target group

Default value: "ip"

xff_header_processing_mode (string) optional

Determines how the load balancer modifies the X-Forwarded-For header in the HTTP request before sending the request to the target. The possible values are append, preserve, and remove. Only valid for Load Balancers of type application. The default is append

Default value: "append"

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

access_logs_bucket_id: The S3 bucket ID for access logs
alb_arn: The ARN of the ALB
alb_arn_suffix: The ARN suffix of the ALB
alb_dns_name: DNS name of ALB
alb_name: The ARN suffix of the ALB
alb_zone_id: The ID of the zone which ALB is provisioned
default_target_group_arn: The default target group ARN
default_target_group_arn_suffix: The default target group ARN suffix
http_listener_arn: The ARN of the HTTP forwarding listener
http_redirect_listener_arn: The ARN of the HTTP to HTTPS redirect listener
https_listener_arn: The ARN of the HTTPS listener
listener_arns: A list of all the listener ARNs
security_group_id: The security group ID of the ALB

Dependencies

Requirements

terraform, version: >= 1.3
aws, version: >= 5.46

Providers

aws, version: >= 5.46

Modules

Name	Version	Source	Description
`access_logs`	0.19.0	`cloudposse/lb-s3-bucket/aws`	n/a
`default_load_balancer_label`	0.25.0	`cloudposse/label/null`	n/a
`default_target_group_label`	0.25.0	`cloudposse/label/null`	n/a
`this`	0.25.0	`cloudposse/label/null`	n/a

Resources

The following resources are used by this module:

aws_lb.default (resource)
aws_lb_listener.http_forward (resource)
aws_lb_listener.http_redirect (resource)
aws_lb_listener.https (resource)
aws_lb_listener_certificate.https_sni (resource)
aws_lb_target_group.default (resource)
aws_security_group.default (resource)
aws_security_group_rule.egress (resource)
aws_security_group_rule.http_ingress (resource)
aws_security_group_rule.https_ingress (resource)

Data Sources

The following data sources are used by this module:

Module: alb

Usage​

Variables​

Required Variables​

Optional Variables​

Context Variables​

Outputs​

Dependencies​

Requirements​

Providers​

Modules​

Resources​

Data Sources​

Module: `alb`

Usage

Variables

Required Variables

Optional Variables

Context Variables

Outputs

Dependencies

Requirements

Providers

Modules

Resources

Data Sources