I am trying to get a value from one stack to another using the below syntax.
stack one-
Outputs:
CompRestAPI:
Description: Rest Api Id
Value: !Ref CompRestAPI
Export:
Name: 'CompRestAPI'
Stack two -
CompRestApiWaf:
Type: AWS::WAFv2::WebACLAssociation
DependsOn: CompApiGatewayStage
Properties:
RestApiId: !ImportValue 'CompRestAPI'
ResourceArn: !Sub 'arn:aws:apigateway:${REGION}:/${RestApiId}/${STAGENAME}-apistage'
WebACLArn: !Ref WafId
I am able to get the values for other resources using 1st syntax, but I am not able to get the value for RestApiId under !Sub
RestApiId: !ImportValue 'CompRestAPI'
ResourceArn: !Sub 'arn:aws:apigateway:${REGION}:/${RestApiId}/apistage'
So is there any way to use !ImportValue under !Sub condition?
I tried it using below code, validation is pass but still showing me an error
Error reason: The ARN isn't valid. A valid ARN begins with arn: and includes other information separated by colons or slashes., field: RESOURCE_ARN, parameter:
CompRestApiWaf:
Type: AWS::WAFv2::WebACLAssociation
DependsOn: CompApiGatewayStage
Properties:
ResourceArn: !Sub 'arn:aws:apigateway:${REGION}:/{!ImportValue CompRestAPI}/stages/apistage'
WebACLArn: !Ref WafId
I am done with it using Fn::join:
SourceArn:
Fn::Join:
- ""
- - 'arn:aws:execute-api:'
- !Ref AWS::Region
- ':'
- !Ref AWS::AccountId
- ':'
- !Ref ApiGatewayRestApiResource
- '/*'
this should work
ResourceArn: !Sub
- 'arn:aws:apigateway:${REGION}:/${CompRestAPI}/stages/apistage'
- CompRestAPI: !ImportValue CompRestAPI
you can expand the second parameter to have multiple keys for multiple imports like so
SecretString: !Sub
- 'postgres://${username}:${password}#${dbhost}:${dbport}/${dbname}'
- username: !Ref 'DBUser'
password: !Ref 'DBPassword'
dbhost: !Ref DbMasterDnsEntry
dbport: !GetAtt AuroraPgCluster.Endpoint.Port
dbname: !Ref 'DBName'
I am trying to create a parameter and would like to combine !Sub and !Import several times.
Parameters:
Environment:
Description: Stackname of Environment
Type: String
Resources:
IAMRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Statement:
- Effect: Allow
Principal:
Service: '*'
Action: ['sts:AssumeRole']
Path: /
Policies:
- PolicyName: S3Files
PolicyDocument:
Statement:
- Sid: 'S3Files'
Effect: Allow
Action:
- 's3:DeleteObjectTagging'
- 's3:GetObjectRetention'
- 's3:ListMultipartUploadParts'
- 's3:PutObject'
- 's3:GetObjectAcl'
- 's3:GetObject'
- 's3:AbortMultipartUpload'
- 's3:PutObjectRetention'
- 's3:GetObjectVersionAcl'
- 's3:GetObjectTagging'
- 's3:PutObjectTagging'
- 's3:DeleteObject'
- 's3:PutObjectAcl'
- 's3:GetObjectVersion'
Resource: !Sub
- '${ARN}/*'
- ARN:
Fn::ImportValue: !Sub ${Environment}:S3:Arn
According to the documentation it should be possible, but unfortunately I always get an error message
Template contains errors.: [/Resources/IAMRole/Type/Policies/0/PolicyDocument/Statement/0/Resource/Fn::Sub/1/ARN] 'null' values are not allowed in templates
How could the UseCase work?
There is a space issue in the Resource section.
Resource: !Sub
- '${ARN}/*'
- ARN:
Fn::ImportValue: !Sub ${Environment}:S3:Arn
It should be
Resource: !Sub
- '${ARN}/*'
- ARN:
Fn::ImportValue: !Sub ${Environment}:S3:Arn
Note: Fn starts under N of ARN instead of A.
Explanation: With the first indentation the line with Fn::ImportValue is considered as an input for !Sub, with the second indentation it becomes the value for ARN: defined the line above it.
Side note: Use 2 spaces or 4 spaces or tabs uniformly throughout the template.
does AWS cloudformation supports creation of Kubernetes pods, services, replica controllers etc or setting up the EKS clusters and worker nodes and using Kubectl to create the resources are the only way?
Not out of the box, but you can if you use a custom resource type backed by a lambda function in CloudFormation.
The AWS EKS quickstart has an example:
AWSTemplateFormatVersion: "2010-09-09"
Description: "deploy an example workload into an existing kubernetes cluster (qs-1p817r5f9)"
Parameters:
KubeConfigPath:
Type: String
KubeConfigKmsContext:
Type: String
Default: "EKSQuickStart"
KubeClusterName:
Type: String
NodeInstanceProfile:
Type: String
QSS3BucketName:
AllowedPattern: ^[0-9a-zA-Z]+([0-9a-zA-Z-]*[0-9a-zA-Z])*$
ConstraintDescription: Quick Start bucket name can include numbers, lowercase
letters, uppercase letters, and hyphens (-). It cannot start or end with a hyphen
(-).
Default: aws-quickstart
Description: S3 bucket name for the Quick Start assets. This string can include
numbers, lowercase letters, uppercase letters, and hyphens (-). It cannot start
or end with a hyphen (-).
Type: String
QSS3KeyPrefix:
AllowedPattern: ^[0-9a-zA-Z-/.]*$
ConstraintDescription: Quick Start key prefix can include numbers, lowercase letters,
uppercase letters, hyphens (-), dots(.) and forward slash (/).
Default: quickstart-amazon-eks/
Description: S3 key prefix for the Quick Start assets. Quick Start key prefix
can include numbers, lowercase letters, uppercase letters, hyphens (-), dots(.) and
forward slash (/).
Type: String
QSS3BucketRegion:
Default: 'us-east-1'
Description: The AWS Region where the Quick Start S3 bucket (QSS3BucketName) is
hosted. When using your own bucket, you must specify this value.
Type: String
LambdaZipsBucketName:
Description: 'OPTIONAL: Bucket Name where the lambda zip files should be placed,
if left blank a bucket will be created.'
Type: String
Default: ''
K8sSubnetIds:
Type: List<AWS::EC2::Subnet::Id>
VPCID:
Type: AWS::EC2::VPC::Id
ControlPlaneSecurityGroup:
Type: AWS::EC2::SecurityGroup::Id
Conditions:
CreateLambdaZipsBucket: !Equals
- !Ref 'LambdaZipsBucketName'
- ''
UsingDefaultBucket: !Equals [!Ref QSS3BucketName, 'aws-quickstart']
Resources:
WorkloadStack:
Type: AWS::CloudFormation::Stack
Properties:
TemplateURL: !Sub
- 'https://${S3Bucket}.s3.${S3Region}.${AWS::URLSuffix}/${QSS3KeyPrefix}templates/example-workload.template.yaml'
- S3Region: !If [UsingDefaultBucket, !Ref 'AWS::Region', !Ref QSS3BucketRegion]
S3Bucket: !If [UsingDefaultBucket, !Sub '${QSS3BucketName}-${AWS::Region}', !Ref QSS3BucketName]
Parameters:
KubeManifestLambdaArn: !GetAtt KubeManifestLambda.Arn
HelmLambdaArn: !GetAtt HelmLambda.Arn
KubeConfigPath: !Ref KubeConfigPath
KubeConfigKmsContext: !Ref KubeConfigKmsContext
KubeClusterName: !Ref KubeClusterName
NodeInstanceProfile: !Ref NodeInstanceProfile
CopyZips:
Type: Custom::CopyZips
Properties:
ServiceToken: !GetAtt 'CopyZipsFunction.Arn'
DestBucket: !Ref LambdaZipsBucketName
SourceBucket: !If [UsingDefaultBucket, !Sub '${QSS3BucketName}-${AWS::Region}', !Ref QSS3BucketName]
Prefix: !Ref 'QSS3KeyPrefix'
Objects:
- functions/packages/Helm/lambda.zip
- functions/packages/DeleteBucketContents/lambda.zip
- functions/packages/KubeManifest/lambda.zip
- functions/packages/LambdaEniCleanup/lambda.zip
VPCLambdaCleanup:
Type: Custom::LambdaCleanup
Properties:
ServiceToken: !GetAtt VPCLambdaCleanupLambdaFunction.Arn
Region: !Ref "AWS::Region"
LambdaFunctionNames:
- !Ref KubeManifestLambda
VPCLambdaCleanupLambdaFunction:
DependsOn: CopyZips
Type: "AWS::Lambda::Function"
Properties:
Handler: lambda_function.lambda_handler
MemorySize: 128
Role: !GetAtt LambdaCleanUpFunctionRole.Arn
Runtime: python3.7
Timeout: 900
Code:
S3Bucket: !Ref LambdaZipsBucketName
S3Key: !Sub '${QSS3KeyPrefix}functions/packages/LambdaEniCleanup/lambda.zip'
HelmLambda:
DependsOn: CopyZips
Type: AWS::Lambda::Function
Properties:
Handler: lambda_function.lambda_handler
MemorySize: 128
Role: !GetAtt ManifestRole.Arn
Runtime: python3.6
Timeout: 900
Code:
S3Bucket: !Ref LambdaZipsBucketName
S3Key: !Sub '${QSS3KeyPrefix}functions/packages/Helm/lambda.zip'
VpcConfig:
SecurityGroupIds: [ !Ref EKSLambdaSecurityGroup ]
SubnetIds: !Ref K8sSubnetIds
KubeManifestLambda:
DependsOn: CopyZips
Type: AWS::Lambda::Function
Properties:
Handler: lambda_function.lambda_handler
MemorySize: 128
Role: !GetAtt ManifestRole.Arn
Runtime: python3.6
Timeout: 900
Code:
S3Bucket: !Ref LambdaZipsBucketName
S3Key: !Sub '${QSS3KeyPrefix}functions/packages/KubeManifest/lambda.zip'
VpcConfig:
SecurityGroupIds: [ !Ref EKSLambdaSecurityGroup ]
SubnetIds: !Ref K8sSubnetIds
DeleteBucketContentsLambda:
DependsOn: CopyZips
Type: AWS::Lambda::Function
Properties:
Handler: lambda_function.lambda_handler
MemorySize: 128
Role: !GetAtt DeleteBucketContentsRole.Arn
Runtime: python3.7
Timeout: 900
Code:
S3Bucket: !Ref LambdaZipsBucketName
S3Key: !Sub '${QSS3KeyPrefix}functions/packages/DeleteBucketContents/lambda.zip'
CopyZipsFunction:
Type: AWS::Lambda::Function
Properties:
Description: Copies objects from a source S3 bucket to a destination
Handler: index.handler
Runtime: python3.7
Role: !GetAtt CopyZipsRole.Arn
Timeout: 900
Code:
ZipFile: |
import json
import logging
import threading
import boto3
import cfnresponse
def copy_objects(source_bucket, dest_bucket, prefix, objects):
s3 = boto3.client('s3')
for o in objects:
key = prefix + o
copy_source = {
'Bucket': source_bucket,
'Key': key
}
print('copy_source: %s' % copy_source)
print('dest_bucket = %s'%dest_bucket)
print('key = %s' %key)
s3.copy_object(CopySource=copy_source, Bucket=dest_bucket,
Key=key)
def delete_objects(bucket, prefix, objects):
s3 = boto3.client('s3')
objects = {'Objects': [{'Key': prefix + o} for o in objects]}
s3.delete_objects(Bucket=bucket, Delete=objects)
def timeout(event, context):
logging.error('Execution is about to time out, sending failure response to CloudFormation')
cfnresponse.send(event, context, cfnresponse.FAILED, {}, physical_resource_id)
def handler(event, context):
physical_resource_id = None
if "PhysicalResourceId" in event.keys():
physical_resource_id = event["PhysicalResourceId"]
# make sure we send a failure to CloudFormation if the function is going to timeout
timer = threading.Timer((context.get_remaining_time_in_millis()
/ 1000.00) - 0.5, timeout, args=[event, context])
timer.start()
print('Received event: %s' % json.dumps(event))
status = cfnresponse.SUCCESS
try:
source_bucket = event['ResourceProperties']['SourceBucket']
dest_bucket = event['ResourceProperties']['DestBucket']
prefix = event['ResourceProperties']['Prefix']
objects = event['ResourceProperties']['Objects']
if event['RequestType'] == 'Delete':
delete_objects(dest_bucket, prefix, objects)
else:
copy_objects(source_bucket, dest_bucket, prefix, objects)
except Exception as e:
logging.error('Exception: %s' % e, exc_info=True)
status = cfnresponse.FAILED
finally:
timer.cancel()
cfnresponse.send(event, context, status, {}, physical_resource_id)
LambdaZipsBucket:
Type: AWS::S3::Bucket
Condition: CreateLambdaZipsBucket
LambdaCleanUpFunctionRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Statement:
- Action: ['sts:AssumeRole']
Effect: Allow
Principal:
Service: [lambda.amazonaws.com]
Version: '2012-10-17'
Path: /
Policies:
- PolicyName: LambdaRole
PolicyDocument:
Version: '2012-10-17'
Statement:
- Action:
- 'logs:CreateLogGroup'
- 'logs:CreateLogStream'
- 'logs:PutLogEvents'
Effect: Allow
Resource: !Sub "arn:${AWS::Partition}:logs:*:*:*"
- Action:
- 'ec2:*'
Effect: Allow
Resource: "*"
DeleteBucketContentsRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Principal:
Service: lambda.amazonaws.com
Action: sts:AssumeRole
ManagedPolicyArns:
- !Sub 'arn:${AWS::Partition}:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole'
Policies:
- PolicyName: deletebucketcontents
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action: s3:*
Resource:
- !Sub 'arn:${AWS::Partition}:s3:::${LambdaZipsBucketName}/*'
- !Sub 'arn:${AWS::Partition}:s3:::${LambdaZipsBucketName}'
CopyZipsRole:
Type: AWS::IAM::Role
Properties:
AssumeRolePolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Principal:
Service: lambda.amazonaws.com
Action: sts:AssumeRole
ManagedPolicyArns:
- !Su 'arn:${AWS::Partition}:iam::aws:policy/service-role/AWSLambdaBasicExecutionRole'
Policies:
- PolicyName: lambda-copier
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action: s3:GetObject
Resource: !Sub
- 'arn:${AWS::Partition}:s3:::${S3Bucket}/${QSS3KeyPrefix}*'
- S3Bucket: !If [UsingDefaultBucket, !Sub '${QSS3BucketName}-${AWS::Region}', !Ref QSS3BucketName]
- Effect: Allow
Action:
- s3:PutObject
- s3:DeleteObject
Resource: !Sub 'arn:${AWS::Partition}:s3:::${LambdaZipsBucketName}/${QSS3KeyPrefix}*'
ManifestRole:
Type: "AWS::IAM::Role"
Properties:
AssumeRolePolicyDocument:
Version: 2012-10-17
Statement:
- Effect: Allow
Principal:
Service: lambda.amazonaws.com
Action: sts:AssumeRole
Policies:
- PolicyName: eksStackPolicy
PolicyDocument:
Version: '2012-10-17'
Statement:
- Effect: Allow
Action: s3:GetObject
Resource: !Sub
- "arn:${AWS::Partition}:s3:::${BucketName}/*"
- S3Bucket: !If [UsingDefaultBucket, !Sub '${QSS3BucketName}-${AWS::Region}', !Ref QSS3BucketName]
- Effect: Allow
Action:
- logs:CreateLogGroup
- logs:CreateLogStream
- logs:PutLogEvents
- ec2:CreateNetworkInterface
- ec2:DescribeNetworkInterfaces
- ec2:DeleteNetworkInterface
Resource:
- "*"
- Action: "kms:decrypt"
Effect: Allow
Resource: "*"
- Action: "s3:GetObject"
Effect: Allow
Resource: "*"
EKSLambdaSecurityGroup:
Type: AWS::EC2::SecurityGroup
Properties:
GroupDescription: Security group for lambda to communicate with cluster API
VpcId: !Ref VPCID
ClusterControlPlaneSecurityGroupIngress:
Type: AWS::EC2::SecurityGroupIngress
Properties:
Description: Allow lambda to communicate with the cluster API Server
GroupId: !Ref ControlPlaneSecurityGroup
SourceSecurityGroupId: !Ref EKSLambdaSecurityGroup
IpProtocol: tcp
ToPort: 443
FromPort: 443
It works by creating a lambda function customer resource KubeManifestLambda and HelmLambda that has kubectl and helm installed respectively, both configured with a role that allows them to access the EKS k8s cluster.
Then these custom resources can be used to deploy k8s manifests and helm charts with custom values, like in this example.
KubeManifestExample:
Type: "Custom::KubeManifest"
Version: '1.0'
Properties:
# The lambda function that executes the manifest against the cluster. This is created in one of the parent stacks
ServiceToken: !Ref KubeManifestLambdaArn
# S3 path to the encrypted config file eg. s3://my-bucket/kube/config.encrypted
KubeConfigPath: !Ref KubeConfigPath
# context for KMS to use when decrypting the file
KubeConfigKmsContext: !Ref KubeConfigKmsContext
# Kubernetes manifest
Manifest:
apiVersion: v1
kind: ConfigMap
metadata:
# If name is not specified it will be automatically generated,
# and can be retrieved with !GetAtt LogicalID.name
#
# name: test
#
# if namespace is not specified, "default" namespace will be used
namespace: kube-system
data:
# examples of consuming outputs of the HelmExample resource below's output. Creates an implicit dependency, so
# this resource will only launch once the HelmExample resource has completed successfully
ServiceCatalogReleaseName: !Ref HelmExample
ServiceCatalogKubernetesServiceName: !GetAtt HelmExample.Service0
This even lets you reference other Cloud formation resources such as RDS instances that are created as part of a workload.
You can use CloudFormation to create EKS cluster and worker nodes but you have to use kubectl for any operation on cluster like creating service, pods, deployments etc.....you can’t use CloudFormation for that
If you use CDK, you can use cluster.add_helm_chart() or HelmChart class. It will create a lambda behind the scenes.
Or you can create a lambda directly with https://docs.aws.amazon.com/cdk/api/v2/python/aws_cdk.lambda_layer_kubectl/README.html
Based on the environment, I am trying to set the URL for a variable: It staging my URL should be https://staging.DNHostedZoneName , if prod - it should just be https://DNSHostedZoneName:
Here's my condition:
Conditions:
IsEnvProd: Fn::Equals [ !Ref Env, 'prod' ]
IsEnvStage: Fn::Equals [ !Ref Env, 'stage' ]
Here's where its been evaluated:
Environment:
- Name: NODE_ENV
Value: !Ref NodeEnv
- Fn::If:
- IsEnvStage
- Name: CORE_URL
Value:
Fn::Join:
- ""
- - "https://"
- "staging"
- "."
- !Ref DnsHostedZoneName
- Name: NCVCORE_URL
Value:
Fn::Join:
- ""
- - "https://"
- !Ref DnsHostedZoneName
I am getting the following error:
Template format error: Conditions can only be boolean operations on parameters and other conditions
Without the full template, it is difficult to try to recreate the issue, but here your snippets refactored with a possible error removed.
Adjusted the conditionals to use all shorthand.
Conditions:
IsEnvProd: !Equals [!Ref "Env", "prod"]
IsEnvStage: !Equals [!Ref "Env", "stage"]
There was an additional space in the YAML so that has been removed, and reformatted.
Environment:
- Name: "NODE_ENV"
Value: !Ref "NodeEnv"
- !If
- "IsEnvStage"
- Name: "CORE_URL"
Value: !Sub "https://staging.${DnsHostedZoneName}"
- Name: "NCVCORE_URL"
Value: !Sub "https://${DnsHostedZoneName}"
Usually the conditions defined are used as an attribute to an aws resource and you specify the name of the condition as a value. You can try https://krunal4amity.github.io - it is an online cloudformation template generator. It takes away a lot of such dreadful work.
You can try to orchestrate creation of specific resources using AWS::NoValue
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/pseudo-parameter-reference.html
Below is taken from variables creation for LambdaFunction
Conditions:
IsProd: !Equals [!Ref Env, "production"]
Environment:
Variables:
USER: !If [IsProd, !GetAtt ...., Ref: AWS::NoValue]
I'm trying to get Cloudtrail on the road and want to set up a Cloudtrail s3bucket. but the Policy does not complete. Here is my code:
CloudtrailBucket:
Type: AWS::S3::Bucket
DeletionPolicy: Delete
Description: Stores all Trails for this account
Properties:
AccessControl: BucketOwnerFullControl
BucketName: !Sub "${AWS::AccountId}-invoice-cloudtrail"
LifecycleConfiguration:
Rules:
- Id: GlacierRule
Prefix: glacier
Status: Enabled
ExpirationInDays: '365'
Transitions:
- TransitionInDays: '1'
StorageClass: Glacier
BucketEncryption:
ServerSideEncryptionConfiguration:
- ServerSideEncryptionByDefault:
SSEAlgorithm: AES256
Tags:
- Key: Name
Value: !Sub '${EnvironmentName} ${Project}-CloudtrailBucket'
VersioningConfiguration:
Status: Suspended
and this is the Policy I want to use:
CloudtrailBucketPolicy:
Type: AWS::S3::BucketPolicy
Properties:
Bucket: !Ref CloudtrailBucket
PolicyDocument:
Statement:
- Sid: AWSCloudTrailAclCheck
Effect: Allow
Principal:
Service: cloudtrail.amazonaws.com
Action:
- s3:GetBucket*
Resource:
- !Sub "arn:aws:s3:::${AWS::AccountId}-invoice-cloudtrail/*"
- Sid: AWSCloudTrailWrite
Effect: Allow
Principal:
Service: cloudtrail.amazonaws.com
Action: s3:PutObject
Resource:
- !Sub "arn:aws:s3:::${AWS::AccountId}-invoice-cloudtrail/*"
Condition:
StringEquals:
s3:x-amz-acl: bucket-owner-full-control
I really dont know what might wrong. the error message is the following:
Action does not apply to any resource(s) in statement (Service: Amazon S3; Status Code: 400; Error Code: MalformedPolicy; Request ID: 7A458D04A5765AC6; S3 Extended Request ID: EYn2is5Oph1+pnZ0u+zEH067fWwD0fyq1+MRGRxJ1qT3WK+e1LFjhhE9fTLOFiBnhSzbItfdrz0=)
I believe you have to change your policy to match the following:
CloudtrailBucketPolicy:
Type: 'AWS::S3::BucketPolicy'
Properties:
Bucket: !Ref CloudtrailBucket
PolicyDocument:
Statement:
- Sid: AWSCloudTrailAclCheck
Effect: Allow
Principal:
Service: cloudtrail.amazonaws.com
Action:
- s3:GetBucketAcl
Resource:
- !Sub "arn:aws:s3:::${AWS::AccountId}-invoice-cloudtrail"
- Sid: AWSCloudTrailWrite
Effect: Allow
Principal:
Service: cloudtrail.amazonaws.com
Action: s3:PutObject
Resource:
- !Sub "arn:aws:s3:::${AWS::AccountId}-invoice-cloudtrail/*"
Condition:
StringEquals:
s3:x-amz-acl: bucket-owner-full-control
The reasoning is that s3:GetBucket* expands to s3:GetBucketAcl, s3:GetBucketCORS, etc (all here), all of these expecting a bucket as resource, and you have provided many objects on your original policy.
So I've changed the resource (removed /*) and also cleaned the policy a bit, since CloudTrail should required only s3:GetBucketAcl.