terraform-aws-s3-terraform-backend


Updated February 14, 2023

Terraform module to deploy the resources to use S3 for remote Terraform state storage. A DynamoDB table is created to enable state locking.

Architecture diagram

WARNING: There is an assumption in this module that you’ll be deploying the state backend to an AWS account that you’re then also going to deploy infrastructure to and you’re likely logged in with an administrator account. No permissions or IAM roles are configured for accessing the state bucket other than via administrator access. If you are consolidating your Terraform state across projects into a single AWS account then you’d probably want to use per-project IAM roles for accessing and modifying state.

Usage

The following example creates the backend:

module "backend" {
  source    = "sr2c/s3-terraform-backend/aws"
  # version   = "x.x.x"
  namespace = "eg"
  name      = "backend"
  stage     = "dev"
}

Requirements

NameVersion
terraform>= 1.3.5
aws>= 4.0.0

Providers

NameVersion
aws4.54.0

Modules

NameSourceVersion
thiscloudposse/label/null0.25.0

Resources

NameType
aws_dynamodb_table.state_tableresource
aws_s3_bucket.state_bucketresource
aws_s3_bucket_server_side_encryption_configuration.state_bucketresource
aws_s3_bucket_versioning.state_bucketresource

Inputs

NameDescriptionTypeDefaultRequired
additional_tag_mapAdditional 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
attributesID 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
contextSingle 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”: [],
“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
}
no
delimiterDelimiter to be used between ID elements.
Defaults to - (hyphen). Set to "" to use no delimiter at all.
stringnullno
descriptor_formatsDescribe 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
dynamodb_read_capacityDynamoDB read capacity unitsnumber5no
dynamodb_write_capacityDynamoDB write capacity unitsnumber5no
enabledSet to false to prevent the module from creating any resourcesboolnullno
environmentID element. Usually used for region e.g. ‘uw2’, ‘us-west-2’, OR role ‘prod’, ‘staging’, ‘dev’, ‘UAT’stringnullno
id_length_limitLimit 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.
numbernullno
label_key_caseControls 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.
stringnullno
label_orderThe 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.
list(string)nullno
label_value_caseControls 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.
stringnullno
labels_as_tagsSet 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.
set(string)
[
“default”
]
no
nameID 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.
stringnullno
namespaceID element. Usually an abbreviation of your organization name, e.g. ’eg’ or ‘cp’, to help ensure generated IDs are globally uniquestringnullno
regex_replace_charsTerraform 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.
stringnullno
s3_versioning_mfa_deleteA boolean that indicates that versions of S3 objects can only be deleted with MFA. (Terraform cannot apply changes
of this value; https://github.com/terraform-providers/terraform-provider-aws/issues/629)
boolfalseno
stageID element. Usually used to indicate role, e.g. ‘prod’, ‘staging’, ‘source’, ‘build’, ’test’, ‘deploy’, ‘release’stringnullno
tagsAdditional tags (e.g. {'BusinessUnit': 'XYZ'}).
Neither the tag keys nor the tag values will be modified by this module.
map(string){}no
tenantID element _(Rarely used, not included by default)_. A customer identifier, indicating who this instance of a resource is forstringnullno

Outputs

No outputs.

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