README ¶
helm-s3 is a Helm plugin that provides Amazon S3 protocol support.
This allows you to have private or public Helm chart repositories hosted on Amazon S3. See this guide to get a detailed example use case overview.
The plugin supports both Helm v2 and v3.
[!NOTE] The documentation is available on website.
Table of contents
- Install
- Configuration
- Usage
- Uninstall
- Advanced Features
- Additional Documentation
- Community and Related Projects
- Contributing
- License
Install
The installation itself is simple as:
$ helm plugin install https://github.com/hypnoglow/helm-s3.git
You can install a specific release version:
$ helm plugin install https://github.com/hypnoglow/helm-s3.git --version 0.16.2
To use the plugin, you do not need any special dependencies. The installer will download versioned release with prebuilt binary from github releases. However, if you want to build the plugin from source, or you want to contribute to the plugin, please see these instructions.
Docker Images
The plugin is also distributed as Docker images. Images are pushed to Docker Hub tagged with plugin release version and suffixed with Helm version. The image built from master branch is also available, note that it should be only used for playing and testing, it is strongly discouraged to use that image for production use cases. Refer to https://hub.docker.com/r/hypnoglow/helm-s3 for details and all available tags.
Configuration
AWS Access
To publish charts to buckets and to fetch from private buckets, you need to
provide valid AWS credentials.
You can do this in the same manner as for AWS CLI
tool.
So, if you want to use the plugin and you are already using AWS CLI
- you are
good to go, no additional configuration required. Otherwise, follow the official guide
to set up credentials.
To minimize security issues, remember to configure your IAM user policies properly. As an example, a setup can provide only read access for users, and write access for a CI that builds and pushes charts to your repository.
Example Read Only IAM policy
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"s3:ListBucket",
"s3:GetObject"
],
"Resource": [
"arn:aws:s3:::bucket-name",
"arn:aws:s3:::bucket-name/*"
]
}
]
}
Example Read and Write IAM policy
{
"Version": "2012-10-17",
"Statement": [
{
"Sid": "files",
"Effect": "Allow",
"Action": [
"s3:PutObjectAcl",
"s3:PutObject",
"s3:GetObjectAcl",
"s3:GetObject",
"s3:DeleteObject"
],
"Resource": [
"arn:aws:s3:::bucket-name/repository-name/*",
"arn:aws:s3:::bucket-name/repository-name"
]
},
{
"Sid": "bucket",
"Effect": "Allow",
"Action": "s3:ListBucket",
"Resource": "arn:aws:s3:::bucket-name"
}
]
}
Helm version mode
The plugin is able to detect if you are using Helm v2 or v3 automatically. If,
for some reason, the plugin does not detect Helm version properly, you can set
HELM_S3_MODE
environment variable to value 2
or 3
to force the mode.
Demonstration
# We have Helm version 3:
$ helm version --short
v3.0.2+g19e47ee
# For some reason, the plugin detects Helm version badly:
$ helm s3 version --mode
helm-s3 plugin version: 0.9.2
Helm version mode: v2
# Force the plugin to operate in v3 mode:
$ HELM_S3_MODE=3 helm s3 version --mode
helm-s3 plugin version: 0.9.2
Helm version mode: v3
Usage
Note: example commands below are provided for Helm v3. If you still use Helm v2, see alternatives marked with a tip 💡.
For now let's omit the process of uploading repository index and charts to s3
and assume you already have your repository index.yaml
file on s3 under path
s3://bucket-name/charts/index.yaml
and a chart archive epicservice-0.5.1.tgz
under path s3://bucket-name/charts/epicservice-0.5.1.tgz
.
Add your repository:
$ helm repo add coolcharts s3://bucket-name/charts
Now you can use it as any other Helm chart repository. Try:
$ helm search coolcharts
NAME VERSION DESCRIPTION
coolcharts/epicservice 0.5.1 A Helm chart.
💡 For Helm v2, use helm search coolcharts
.
To install the chart:
$ helm install coolchart/epicservice --version "0.5.1"
Fetching also works:
$ helm pull coolchart/epicservice --version "0.5.1"
💡 For Helm v2, use helm fetch
.
Alternatively:
$ helm pull s3://bucket-name/charts/epicservice-0.5.1.tgz
Init
To create a new repository, use init
:
$ helm s3 init s3://bucket-name/charts
This command generates an empty index.yaml and uploads it to the S3 bucket
under /charts
key.
To work with this repo by its name, first you need to add it using native helm command:
$ helm repo add mynewrepo s3://bucket-name/charts
Push
Now you can push your chart to this repo:
$ helm s3 push ./epicservice-0.7.2.tgz mynewrepo
You may want to push the chart with relative URL, see Relative chart URLs.
On push, both remote and local repo indexes are automatically updated (that
means you don't need to run helm repo update
).
Your pushed chart is available:
$ helm search repo mynewrepo
NAME VERSION DESCRIPTION
mynewrepo/epicservice 0.7.2 A Helm chart.
💡 For Helm v2, use helm search mynewrepo
.
Note that the plugin denies push when the chart with the same version already
exists in the repository. This behavior is intentional. It is useful, for
example, in CI automated pushing: if someone forgets to bump chart version - the
chart would not be overwritten. However, in some cases you want to replace
existing chart version. To do so, add --force
flag to a push command:
$ helm s3 push --force ./epicservice-0.7.2.tgz mynewrepo
To see other available options, use --help
flag:
$ helm s3 push --help
Delete
To delete specific chart version from the repository:
$ helm s3 delete epicservice --version 0.7.2 mynewrepo
As always, both remote and local repo indexes updated automatically.
The chart is deleted from the repo:
$ helm search repo mynewrepo/epicservice
No results found
💡 For Helm v2, use helm search mynewrepo/epicservice
Reindex
If your repository somehow became inconsistent or broken, you can use reindex to recreate the index in accordance with the charts in the repository.
$ helm s3 reindex mynewrepo
You may want to reindex the repo with relative chart URLs, see Relative chart URLs.
Uninstall
$ helm plugin remove s3
Thank you for using the plugin! 👋
Advanced Features
Relative chart URLs
Charts can be push
-ed with --relative
flag so their URLs in the index file
will be relative to your repository root. This can be useful in various
scenarios, e.g. serving charts via HTTP, serving charts from replicated buckets,
etc.
Also, you can run reindex
command with --relative
flag to make all chart
URLs relative in an existing repository.
Serving charts via HTTP
You can enable HTTP access to your S3 bucket and serve charts via HTTP URLs, so your repository users won't have to install this plugin.
To do this, you need your charts to have relative URLs in the index. See Relative chart URLs.
Example of setting up a public repo using Virtual hosting of buckets
-
Create S3 bucket named
example-bucket
in EU (Frankfurt)eu-central-1
region. -
Go to "Permissions", edit Bucket Policy:
{ "Version": "2012-10-17", "Statement": [ { "Effect": "Allow", "Principal": "*", "Action": [ "s3:ListBucket", "s3:GetObject" ], "Resource": [ "arn:aws:s3:::example-bucket", "arn:aws:s3:::example-bucket/*" ] } ] }
-
Initialize repository:
$ helm s3 init s3://example-bucket Initialized empty repository at s3://example-bucket
-
Add repository:
$ helm repo add example-bucket s3://example-bucket "example-bucket" has been added to your repositories
-
Create demo chart:
$ helm create petstore Creating petstore $ helm package petstore --version 1.0.0 Successfully packaged chart and saved it to: petstore-1.0.0.tgz
-
Push chart:
$ helm s3 push ./petstore-1.0.0.tgz --relative Successfully uploaded the chart to the repository.
-
The bucket is public and chart repo is set up. Now users can use the repo without the need to install helm-s3 plugin.
Add HTTP repo:
$ helm repo add example-bucket-http https://example-bucket.s3.eu-central-1.amazonaws.com/ "example-bucket-http" has been added to your repositories
Search and download charts:
$ helm search repo example-bucket-http NAME CHART VERSION APP VERSION DESCRIPTION example-bucket-http/petstore 1.0.0 1.16.0 A Helm chart for Kubernetes $ helm pull example-bucket-http/petstore --version 1.0.0
ACL
In use cases where you share a repo across multiple AWS accounts, you may want
the ability to define object ACLs to allow charts to persist their permissions
across accounts. To do so, add the flag --acl="ACL_POLICY"
. The list of ACLs
can be found here:
$ helm s3 push --acl="bucket-owner-full-control" ./epicservice-0.7.2.tgz mynewrepo
Note that if you do use ACL, you need to add --acl
flag for all commands, even
for 'delete', because the index file is still updated when you remove a chart.
You can also set the default ACL be setting the S3_ACL
environment variable.
Timeout
The default timeout for all commands is 5 minutes. This is an opinionated default to be suitable for MFA use, among other things.
If you don't use MFA, it may be reasonable to lower the timeout for most commands, e.g. to 10 seconds. In contrast, in cases where you want to reindex a big repository with thousands of charts, you definitely want to increase the timeout.
Example:
$ helm s3 push --timeout=10s ./epicservice-0.7.2.tgz mynewrepo
Using alternative S3-compatible vendors
The plugin assumes Amazon S3 by default. However, it can work with any
S3-compatible object storage, like minio,
DreamObjects and others. To
configure the plugin to work alternative S3 backend, just define AWS_ENDPOINT
(and optionally AWS_DISABLE_SSL
if you play with Minio locally):
$ export AWS_ENDPOINT=localhost:9000
$ export AWS_DISABLE_SSL=true
See these integration tests that use local minio docker container for a complete example.
Using S3 bucket ServerSide Encryption
To enable S3 SSE, export environment variable AWS_S3_SSE
and set it to desired
type, e.g. AES256
.
S3 bucket location
The plugin will look for the bucket in the region inferred by the environment.
This can be controlled by exporting one of HELM_S3_REGION
, AWS_REGION
or
AWS_DEFAULT_REGION
, in order of precedence.
Since v0.11.0 the plugin supports dynamic S3 bucket region retrieval, so in most cases you don't need to provide the region. The plugin will detect it automatically and work without issues.
AWS SSO
The plugin supports AWS IAM Identity Center (aka AWS SSO) authentication.
To use AWS SSO, make sure you configured it via AWS CLI:
$ aws configure sso
SSO session name (Recommended): my-sso
SSO start URL [None]: https://my-sso-portal.awsapps.com/start
SSO region [None]: us-east-1
SSO registration scopes [None]: sso:account:access
...
CLI default client Region [None]: us-east-1
CLI default output format [None]:
CLI profile name [...]: YOUR-PROFILE-NAME
Then, set AWS_PROFILE
environment variable to the profile name you used in
the previous step:
$ export AWS_PROFILE=YOUR-PROFILE-NAME
Now you can use the plugin as usual.
Additional Documentation
Additional documentation is available in the docs directory. This currently includes:
- Estimated usage cost calculation
- Best Practices for organizing your repositories.
Community and Related Projects
- Helm | Related Projects and Documentation
- Set up a Helm v3 chart repository in Amazon S3 - AWS Prescriptive Guidance
- Deploy Kubernetes resources and packages using Amazon EKS and a Helm chart repository in Amazon S3 - AWS Prescriptive Guidance
- Chart sources - Flux Helm Operator
- How to create a Helm chart repository using Amazon S3
Contributing
Contributions are welcome. Please see these instructions that will help you to develop the plugin.