lambda

This component is responsible for provisioning Lambda functions.

Usage

Stack Level: Regional

Stack configuration for defaults:

components:
  terraform:
    lambda-defaults:
      metadata:
        type: abstract
      settings:
        spacelift:
          workspace_enabled: true
      vars:
        enabled: true

Sample App Yaml Entry:

import:
  - catalog/lambda/defaults

components:
  terraform:
    lambda/hello-world-py:
      metadata:
        component: lambda
        inherits:
          - lambda/defaults
      vars:
        name: hello-world-py
        function_name: main
        description: Hello Lambda from Python!
        handler: lambda.lambda_handler # in go this is the compiled binary, python it's filename.function
        memory_size: 256
        # https://docs.aws.amazon.com/lambda/latest/dg/lambda-runtimes.html
        runtime: python3.9
        package_type: Zip # `Zip` or `Image`
        policy_json: |
          {
            "Version": "2012-10-17",
            "Statement": [
              {
                "Sid": "ListAllBuckets",
                "Effect": "Allow",
                "Action": "s3:ListAllMyBuckets",
                "Resource": "*"
              }
            ]
          }
        iam_policy:
          statements:
            - sid: AllowSQSWorkerWriteAccess
              effect: Allow
              actions:
                - sqs:SendMessage
                - sqs:SendMessageBatch
              resources:
                - arn:aws:sqs:*:111111111111:worker-queue
        # Filename example
        filename: lambdas/hello-world-python/output.zip # generated by zip variable.
        zip:
          enabled: true
          input_dir: hello-world-python
          output: hello-world-python/output.zip

        # S3 Source Example
        # s3_bucket_name: lambda-source # lambda main.tf calculates the rest of the bucket_name
        # s3_key: hello-world-go.zip

Notifications:

SQS

sqs_notifications:
  my-service-a:
    sqs_component:
      component: sqs-queue/my-service-a
  my-service-b:
    sqs_arn: arn:aws:sqs:us-west-2:111111111111:my-service-b

S3

s3_notifications:
  my-service-a:
    bucket_component:
      component: s3-bucket/my-service-a
    events: ["s3:ObjectCreated:*"]
  my-service-b:
    bucket_name: my-service-b
    events: ["s3:ObjectCreated:*", "s3:ObjectRemoved:*"]

Cron (CloudWatch Event)

cloudwatch_event_rules:
  schedule-a:
    schedule_expression: "rate(5 minutes)"
  schedule-b:
    schedule_expression: "cron(0 20 * * ? *)"

Variables

Required Variables

region (string) required

AWS Region

Optional Variables

architectures (list(string)) optional

Instruction set architecture for your Lambda function. Valid values are ["x86_64"] and ["arm64"].
Default is ["x86_64"]. Removing this attribute, function's architecture stay the same.

Default value: null

cicd_s3_key_format (string) optional

The format of the S3 key to store the latest version/sha of the Lambda function. This is used with cicd_ssm_param_name. Defaults to 'stage/{stage}/lambda/{function_name}/%s.zip'

Default value: null

cicd_ssm_param_name (string) optional

The name of the SSM parameter to store the latest version/sha of the Lambda function. This is used with cicd_s3_key_format

Default value: null

cloudwatch_event_rules optional

Creates EventBridge (CloudWatch Events) rules for invoking the Lambda Function along with the required permissions.

Type:

map(object({
description         = optional(string)
event_bus_name      = optional(string)
event_pattern       = optional(string)
is_enabled          = optional(bool)
name_prefix         = optional(string)
role_arn            = optional(string)
schedule_expression = optional(string)
}))

Default value: { }

cloudwatch_lambda_insights_enabled (bool) optional

Enable CloudWatch Lambda Insights for the Lambda Function.

Default value: false

cloudwatch_logs_kms_key_arn (string) optional

The ARN of the KMS Key to use when encrypting log data.

Default value: null

cloudwatch_logs_retention_in_days (number) optional

Specifies the number of days you want to retain log events in the specified log group. Possible values are:
1, 3, 5, 7, 14, 30, 60, 90, 120, 150, 180, 365, 400, 545, 731, 1827, 3653, and 0. If you select 0, the events in the
log group are always retained and never expire.

Default value: null

custom_iam_policy_arns (set(string)) optional

ARNs of IAM policies to be attached to the Lambda role

Default value: [ ]

dead_letter_config_target_arn (string) optional

ARN of an SNS topic or SQS queue to notify when an invocation fails. If this option is used, the function's IAM role
must be granted suitable access to write to the target object, which means allowing either the sns:Publish or
sqs:SendMessage action on this ARN, depending on which service is targeted."

Default value: null

description (string) optional

Description of what the Lambda Function does.

Default value: null

filename (string) optional

The path to the function's deployment package within the local filesystem. Works well with the zip variable. If defined, The s3_-prefixed options and image_uri cannot be used.

Default value: null

function_name (string) optional

Unique name for the Lambda Function.

Default value: null

function_url_enabled (bool) optional

Create a aws_lambda_function_url resource to expose the Lambda function

Default value: false

handler (string) optional

The function entrypoint in your code.

Default value: null

iam_policy optional

IAM policy to attach to the Lambda role, specified as a Terraform object. This can be used with or instead of var.policy_json.

Type:

object({
policy_id = optional(string, null)
version   = optional(string, null)
statements = list(object({
  sid           = optional(string, null)
  effect        = optional(string, null)
  actions       = optional(list(string), null)
  not_actions   = optional(list(string), null)
  resources     = optional(list(string), null)
  not_resources = optional(list(string), null)
  conditions = optional(list(object({
    test     = string
    variable = string
    values   = list(string)
  })), [])
  principals = optional(list(object({
    type        = string
    identifiers = list(string)
  })), [])
  not_principals = optional(list(object({
    type        = string
    identifiers = list(string)
  })), [])
}))
})

Default value: null

iam_policy_description (string) optional

Description of the IAM policy for the Lambda IAM role

Default value: "Minimum SSM read permissions for Lambda IAM Role"

image_config (any) optional

The Lambda OCI image configurations
block with three (optional) arguments:

• entry_point - The ENTRYPOINT for the docker image (type list(string)).
  
• command - The CMD for the docker image (type list(string)).
  
• working_directory - The working directory for the docker image (type string).
  

Default value: { }

image_uri (string) optional

The ECR image URI containing the function's deployment package. Conflicts with filename, s3_bucket_name, s3_key, and s3_object_version.

Default value: null

kms_key_arn (string) optional

Amazon Resource Name (ARN) of the AWS Key Management Service (KMS) key that is used to encrypt environment variables.
If this configuration is not provided when environment variables are in use, AWS Lambda uses a default service key.
If this configuration is provided when environment variables are not in use, the AWS Lambda API does not save this
configuration and Terraform will show a perpetual difference of adding the key. To fix the perpetual difference,
remove this configuration.

Default value: ""

lambda_at_edge_enabled (bool) optional

Enable Lambda@Edge for your Node.js or Python functions. The required trust relationship and publishing of function versions will be configured in this module.

Default value: false

lambda_environment optional

Environment (e.g. ENV variables) configuration for the Lambda function enable you to dynamically pass settings to your function code and libraries.

Type:

object({
variables = map(string)
})

Default value: null

layers (list(string)) optional

List of Lambda Layer Version ARNs (maximum of 5) to attach to the Lambda Function.

Default value: [ ]

memory_size (number) optional

Amount of memory in MB the Lambda Function can use at runtime.

Default value: 128

package_type (string) optional

The Lambda deployment package type. Valid values are Zip and Image.

Default value: "Zip"

permissions_boundary (string) optional

ARN of the policy that is used to set the permissions boundary for the role

Default value: ""

policy_json (string) optional

IAM policy to attach to the Lambda role, specified as JSON. This can be used with or instead of var.iam_policy.

Default value: null

publish (bool) optional

Whether to publish creation/change as new Lambda Function Version.

Default value: false

reserved_concurrent_executions (number) optional

The amount of reserved concurrent executions for this lambda function. A value of 0 disables lambda from being triggered and -1 removes any concurrency limitations.

Default value: -1

runtime (string) optional

The runtime environment for the Lambda function you are uploading.

Default value: null

s3_bucket_component optional

The bucket component to use for the S3 bucket containing the function's deployment package. Conflicts with s3_bucket_name, filename and image_uri.

Type:

object({
component   = string
tenant      = optional(string)
stage       = optional(string)
environment = optional(string)
})

Default value: null

s3_bucket_name (string) optional

The name suffix of the S3 bucket containing the function's deployment package. Conflicts with filename and image_uri.
This bucket must reside in the same AWS region where you are creating the Lambda function.

Default value: null

s3_key (string) optional

The S3 key of an object containing the function's deployment package. Conflicts with filename and image_uri.

Default value: null

s3_notifications optional

A map of S3 bucket notifications to trigger the Lambda function

Type:

map(object({
bucket_name = optional(string)
bucket_component = optional(object({
  component   = string
  environment = optional(string)
  tenant      = optional(string)
  stage       = optional(string)
}))
events         = optional(list(string))
filter_prefix  = optional(string)
filter_suffix  = optional(string)
source_account = optional(string)
}))

Default value: { }

s3_object_version (string) optional

The object version containing the function's deployment package. Conflicts with filename and image_uri.

Default value: null

source_code_hash (string) optional

Used to trigger updates. Must be set to a base64-encoded SHA256 hash of the package file specified with either
filename or s3_key. The usual way to set this is filebase64sha256('file.zip') where 'file.zip' is the local filename
of the lambda function source archive.

Default value: ""

sqs_notifications optional

A map of SQS queue notifications to trigger the Lambda function

Type:

map(object({
sqs_arn = optional(string)
sqs_component = optional(object({
  component   = string
  environment = optional(string)
  tenant      = optional(string)
  stage       = optional(string)
}))
batch_size          = optional(number)
source_account      = optional(string)
on_failure_arn      = optional(string)
maximum_concurrency = optional(number)
}))

Default value: { }

ssm_parameter_names (list(string)) optional

List of AWS Systems Manager Parameter Store parameter names. The IAM role of this Lambda function will be enhanced
with read permissions for those parameters. Parameters must start with a forward slash and can be encrypted with the
default KMS key.

Default value: null

timeout (number) optional

The amount of time the Lambda Function has to run in seconds.

Default value: 3

tracing_config_mode (string) optional

Tracing config mode of the Lambda function. Can be either PassThrough or Active.

Default value: null

vpc_config optional

Provide this to allow your function to access your VPC (if both 'subnet_ids' and 'security_group_ids' are empty then
vpc_config is considered to be empty or unset, see https://docs.aws.amazon.com/lambda/latest/dg/vpc.html for details).

Type:

object({
security_group_ids = list(string)
subnet_ids         = list(string)
})

Default value: null

zip optional

Zip Configuration for local file deployments

Type:

object({
enabled   = optional(bool, false)
output    = optional(string, "output.zip")
input_dir = optional(string, null)
})

Default value:

{
  "enabled": false,
  "output": "output.zip"
}

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

arn

ARN of the lambda function

function_name

Lambda function name

invoke_arn

Invoke ARN of the lambda function

qualified_arn

ARN identifying your Lambda Function Version (if versioning is enabled via publish = true)

role_arn

Lambda IAM role ARN

role_name

Lambda IAM role name

Dependencies

Requirements

• terraform, version: >= 1.3.0
• archive, version: >= 2.3.0
• aws, version: >= 4.9.0
• random, version: >= 3.0.0

Providers

• archive, version: >= 2.3.0
• aws, version: >= 4.9.0
• random, version: >= 3.0.0

Modules

Name	Version	Source	Description
cloudwatch_event_rules_label	0.25.0	cloudposse/label/null	n/a
iam_policy	2.0.2	cloudposse/iam-policy/aws	n/a
iam_roles	latest	../account-map/modules/iam-roles	n/a
lambda	0.6.1	cloudposse/lambda-function/aws	n/a
s3_bucket	1.8.0	cloudposse/stack-config/yaml//modules/remote-state	n/a
s3_bucket_notifications_component	1.8.0	cloudposse/stack-config/yaml//modules/remote-state	n/a
sqs_iam_policy	2.0.2	cloudposse/iam-policy/aws	n/a
sqs_queue	1.8.0	cloudposse/stack-config/yaml//modules/remote-state	n/a
this	0.25.0	cloudposse/label/null	n/a

Resources

The following resources are used by this module:

• aws_cloudwatch_event_rule.event_rules (resource)
• aws_cloudwatch_event_target.sns (resource)
• aws_iam_role_policy_attachment.default (resource)
• aws_iam_role_policy_attachment.sqs_default (resource)
• aws_lambda_event_source_mapping.event_source_mapping (resource)
• aws_lambda_function_url.lambda_url (resource)
• aws_lambda_permission.allow_cloudwatch_to_call_lambda (resource)
• aws_lambda_permission.s3_notification (resource)
• aws_s3_bucket_notification.s3_notifications (resource)
• random_pet.zip_recreator (resource)

Data Sources

The following data sources are used by this module:

• archive_file.lambdazip (data source)
• aws_ssm_parameter.cicd_ssm_param (data source)

References

• cloudposse/terraform-aws-components - Cloud Posse's upstream component