Module: iam-s3-user
Terraform module to provision a basic IAM user with permissions to access S3 resources, e.g. to give the user read/write/delete access to the objects in an S3 bucket.
Suitable for CI/CD systems (e.g. TravisCI, CircleCI) or systems which are external to AWS that cannot leverage AWS IAM Instance Profiles or AWS OIDC.
By default, IAM users, groups, and roles have no access to AWS resources. IAM policies are the means by which privileges are granted to users, groups, or roles. It is recommended that IAM policies be applied directly to groups and roles but not users. This module intentionally attaches an IAM policy directly to the user and does not use groups
The IAM user name is constructed using terraform-null-label
and some input is required. The simplest input is name
. By default the name will be converted to lower case
and all non-alphanumeric characters except for hyphen will be removed. See the documentation for terraform-null-label
to learn how to override these defaults if desired.
If an AWS Access Key is created, it is stored either in SSM Parameter Store or is provided as a module output, but not both. Using SSM Parameter Store is recommended because module outputs are stored in plaintext in the Terraform state file.
Usage
This example will create an IAM user and allow read access to all objects in the S3 bucket examplebucket
module "s3_user" {
source = "cloudposse/iam-s3-user/aws"
# Cloud Posse recommends pinning every module to a specific version
# version = "x.x.x"
namespace = "eg"
stage = "test"
name = "app"
s3_actions = ["s3:GetObject"]
s3_resources = "arn:aws:s3:::examplebucket/*"
}
Variables
Required Variables
s3_resources
(list(string)
) requiredS3 resources to apply the actions specified in the policy
Optional Variables
create_iam_access_key
(bool
) optionalSet
true
to create an IAM Access Key for the user.
To rotate the key, setfalse
to delete it and then back totrue
to create a new key.
Best practice is to never create a key and instead authenticate with OIDC or some other mechanism
that does not require long-lived bearer tokens.Default value:
true
force_destroy
(bool
) optionalDestroy even if it has non-Terraform-managed IAM access keys, login profiles or MFA devices
Default value:
false
path
(string
) optionalPath in which to create the user
Default value:
"/"
permissions_boundary
(string
) optionalPermissions Boundary ARN to attach to our created user
Default value:
null
s3_actions
(list(string)
) optionalActions to allow in the policy
Default value:
[
"s3:GetObject"
]ssm_base_path
(string
) optionalThe base path for SSM parameters where secrets are stored
Default value:
"/s3_user/"
ssm_enabled
(bool
) optionalSet
true
to store secrets in SSM Parameter Store,
false
to store secrets in Terraform state as outputs.
Since Terraform state would contain the secrets in plaintext,
use of SSM Parameter Store is recommended.Default value:
false
Context Variables
The following variables are defined in the context.tf
file of this module and part of the terraform-null-label pattern.
context.tf
file of this module and part of the terraform-null-label pattern.additional_tag_map
(map(string)
) optionalAdditional key-value pairs to add to each map in
tags_as_list_of_maps
. Not added totags
orid
.
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)
) optionalID element. Additional attributes (e.g.
workers
orcluster
) to add toid
,
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 thedelimiter
and treated as a single ID element.Required: No
Default value:
[ ]
context
(any
) optionalSingle object for setting entire context at once.
See description of individual variables for details.
Leave string and numeric variables asnull
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
) optionalDelimiter 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
) optionalDescribe 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 isany
so the map values can later be enhanced to provide additional options.)
format
is a Terraform format string to be passed to theformat()
function.
labels
is a list of labels, in order, to pass toformat()
function.
Label values will be normalized before being passed toformat()
so they will be
identical to how they appear inid
.
Default is{}
(descriptors
output will be empty).Required: No
Default value:
{ }
enabled
(bool
) optionalSet to false to prevent the module from creating any resources
Required: NoDefault value:
null
environment
(string
) optionalID element. Usually used for region e.g. 'uw2', 'us-west-2', OR role 'prod', 'staging', 'dev', 'UAT'
Required: NoDefault value:
null
id_length_limit
(number
) optionalLimit
id
to this many characters (minimum 6).
Set to0
for unlimited length.
Set tonull
for keep the existing setting, which defaults to0
.
Does not affectid_full
.Required: No
Default value:
null
label_key_case
(string
) optionalControls the letter case of the
tags
keys (label names) for tags generated by this module.
Does not affect keys of tags passed in via thetags
input.
Possible values:lower
,title
,upper
.
Default value:title
.Required: No
Default value:
null
label_order
(list(string)
) optionalThe 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
) optionalControls 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 thetags
input.
Possible values:lower
,title
,upper
andnone
(no transformation).
Set this totitle
and setdelimiter
to""
to yield Pascal Case IDs.
Default value:lower
.Required: No
Default value:
null
labels_as_tags
(set(string)
) optionalSet 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 thetags
output.
Set to[]
to suppress all generated tags.
Notes:
The value of thename
tag, if included, will be theid
, not thename
.
Unlike othernull-label
inputs, the initial setting oflabels_as_tags
cannot be
changed in later chained modules. Attempts to change it will be silently ignored.Required: No
Default value:
[
"default"
]name
(string
) optionalID element. Usually the component or solution name, e.g. 'app' or 'jenkins'.
This is the only ID element not also included as atag
.
The "name" tag is set to the fullid
string. There is no tag with the value of thename
input.Required: No
Default value:
null
namespace
(string
) optionalID element. Usually an abbreviation of your organization name, e.g. 'eg' or 'cp', to help ensure generated IDs are globally unique
Required: NoDefault value:
null
regex_replace_chars
(string
) optionalTerraform 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
) optionalID element. Usually used to indicate role, e.g. 'prod', 'staging', 'source', 'build', 'test', 'deploy', 'release'
Required: NoDefault value:
null
tags
(map(string)
) optionalAdditional 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
) optionalID element (Rarely used, not included by default). A customer identifier, indicating who this instance of a resource is for
Required: NoDefault value:
null
Outputs
access_key_id
Access Key ID
access_key_id_ssm_path
The SSM Path under which the S3 User's access key ID is stored
secret_access_key
Secret Access Key. This will be written to the state file in plain-text
secret_access_key_ssm_path
The SSM Path under which the S3 User's secret access key is stored
user_arn
The ARN assigned by AWS for the user
user_name
Normalized IAM user name
user_unique_id
The user unique ID assigned by AWS
Dependencies
Requirements
terraform
, version:>= 0.13.0
aws
, version:>= 2.0
Providers
aws
, version:>= 2.0
Modules
Name | Version | Source | Description |
---|---|---|---|
s3_user | 1.2.1 | cloudposse/iam-system-user/aws | n/a |
this | 0.25.0 | cloudposse/label/null | n/a |
Resources
The following resources are used by this module:
aws_iam_user_policy.default
(resource)
Data Sources
The following data sources are used by this module:
aws_iam_policy_document.default
(data source)