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https://github.com/external-secrets/kubernetes-external-secrets

Integrate external secret management systems with Kubernetes
https://github.com/external-secrets/kubernetes-external-secrets

aws aws-secrets-manager hashicorp kubernetes kubernetes-external-secrets secrets-management secrets-manager vault

Last synced: about 1 month ago
JSON representation

Integrate external secret management systems with Kubernetes

Host: GitHub
URL: https://github.com/external-secrets/kubernetes-external-secrets
Owner: external-secrets
License: mit
Archived: true
Created: 2018-12-12T18:26:36.000Z (almost 6 years ago)
Default Branch: master
Last Pushed: 2022-05-28T13:05:36.000Z (over 2 years ago)
Last Synced: 2024-09-22T06:32:01.799Z (about 1 month ago)
Topics: aws, aws-secrets-manager, hashicorp, kubernetes, kubernetes-external-secrets, secrets-management, secrets-manager, vault
Language: JavaScript
Homepage:
Size: 3.14 MB
Stars: 2,605
Watchers: 45
Forks: 403
Open Issues: 1
Metadata Files:
- Readme: README.md
- Changelog: CHANGELOG.md
- Contributing: CONTRIBUTING.md
- License: LICENSE
- Code of conduct: CODE_OF_CONDUCT.md
- Security: SECURITY.md

Awesome Lists containing this project

awesome-repositories - external-secrets/kubernetes-external-secrets - Integrate external secret management systems with Kubernetes (JavaScript)
awesome-kubernetes-security - kubernetes-external-secrets - Tool to get External Secrets from Hashicorp Vault and AWS SSM (Open Source Projects)
jimsghstars - external-secrets/kubernetes-external-secrets - Integrate external secret management systems with Kubernetes (JavaScript)

README

# Deprecated

This project has been [deprecated](https://github.com/external-secrets/kubernetes-external-secrets/issues/864).
Please take a look at ESO (External Secrets Operator) instead https://github.com/external-secrets/external-secrets

[![Artifact HUB](https://img.shields.io/endpoint?url=https://artifacthub.io/badge/repository/external-secrets)](https://artifacthub.io/packages/search?repo=external-secrets) [![LGTM Alerts](https://img.shields.io/lgtm/alerts/github/external-secrets/kubernetes-external-secrets)](https://lgtm.com/projects/g/external-secrets/kubernetes-external-secrets)

## History

This project was moved from the [GoDaddy](https://github.com/godaddy) to the [external-secrets](https://github.com/external-secrets) GitHub organization in an effort to consolidate different projects with the same objective. More information [here](https://github.com/external-secrets/kubernetes-external-secrets/issues/554#issuecomment-728984416).

# Kubernetes External Secrets

Kubernetes External Secrets allows you to use external secret
management systems, like [AWS Secrets Manager](https://aws.amazon.com/secrets-manager/) or
[HashiCorp Vault](https://www.vaultproject.io/), to securely add secrets in
Kubernetes. Read more about the design and motivation for Kubernetes
External Secrets on the [GoDaddy Engineering
Blog](https://godaddy.github.io/2019/04/16/kubernetes-external-secrets/).

The community and maintainers of this project and related Kubernetes
secret management projects use the
[`#external-secrets`](https://kubernetes.slack.com/archives/C017BF84G2Y)
channel on the Kubernetes slack for discussion and brainstorming.

## How it works

The project extends the Kubernetes API by adding an `ExternalSecrets` object using [Custom Resource Definition](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/) and a controller to implement the behavior of the object itself.

An `ExternalSecret` declares how to fetch the secret data, while the controller converts all `ExternalSecrets` to `Secrets`.
The conversion is completely transparent to `Pods` that can access `Secrets` normally.

By default `Secrets` are not encrypted at rest and are open to attack, either via the `etcd` server or via backups of `etcd` data.
To mitigate this risk, use an
[external secret management system with a KMS plugin](https://kubernetes.io/docs/tasks/administer-cluster/kms-provider/)
to encrypt `Secrets` stored in `etcd`.

## System architecture

![Architecture](architecture.png)

1. `ExternalSecrets` are added in the cluster (e.g., `kubectl apply -f external-secret-example.yml`)
1. Controller fetches `ExternalSecrets` using the Kubernetes API
1. Controller uses `ExternalSecrets` to fetch secret data from external providers (e.g, AWS Secrets Manager)
1. Controller upserts `Secrets`
1. `Pods` can access `Secrets` normally

## How to use it

### Install with Helm

The official [helm chart](charts/kubernetes-external-secrets) can be used to create the `kubernetes-external-secrets` resources and `Deployment` on a [Kubernetes](http://kubernetes.io) cluster using the [Helm](https://helm.sh) package manager.

```bash
$ helm repo add external-secrets https://external-secrets.github.io/kubernetes-external-secrets/
$ helm install [RELEASE_NAME] external-secrets/kubernetes-external-secrets
```

For more details about configuration see the [helm chart docs](charts/kubernetes-external-secrets/README.md)

### Install with kubectl

If you don't want to install helm on your cluster and just want to use `kubectl` to install `kubernetes-external-secrets`, you could get the `helm` client cli first and then use the following sample command to generate kubernetes manifests:

```bash
$ helm template --include-crds --output-dir ./output_dir external-secrets/kubernetes-external-secrets
```

The generated kubernetes manifests will be in `./output_dir` and can be applied to deploy `kubernetes-external-secrets` to the cluster.

### Secrets Manager access

For `kubernetes-external-secrets` to be able to retrieve your secrets it will need access to your secret backend.

#### AWS based backends

Access to AWS secrets backends (SSM & secrets manager) can be granted in various ways:

1. Granting your nodes explicit access to your secrets using the [node instance role](https://docs.aws.amazon.com/eks/latest/userguide/worker_node_IAM_role.html) (easy for experimentation, not recommended)

2. [IAM roles for service accounts](https://docs.aws.amazon.com/eks/latest/userguide/iam-roles-for-service-accounts.html).

3. Per pod IAM authentication: [kiam](https://github.com/uswitch/kiam) or [kube2iam](https://github.com/jtblin/kube2iam).

4. Directly provide AWS access credentials to the `kubernetes-external-secrets` pod by environmental variables.

Optionally configure custom endpoints using environment variables
- [AWS_SM_ENDPOINT](https://docs.aws.amazon.com/general/latest/gr/asm.html) - Useful to set endpoints for FIPS compliance.
- [AWS_STS_ENDPOINT](https://docs.aws.amazon.com/general/latest/gr/sts.html) - Useful to set endpoints for FIPS compliance or regional latency.
- [AWS_SSM_ENDPOINT](https://docs.aws.amazon.com/general/latest/gr/ssm.html) - Useful to set endpoints for FIPS compliance or custom VPC endpoint.

##### Using AWS access credentials

Set `AWS_ACCESS_KEY_ID` and `AWS_SECRET_ACCESS_KEY` env vars in the `kubernetes-external-secrets` session/pod.
You can use `envVarsFromSecret` in the helm chart to create these env vars from existing k8s secrets.

Additionally, you can specify a `roleArn` which will be assumed before retrieving the secret.
You can limit the range of roles which can be assumed by this particular _namespace_ by using annotations on the namespace resource. The annotation key is configurable (see [above](#aws-based-backends)). The annotation value is evaluated as a regular expression and tries to match the `roleArn`.

```yaml
kind: Namespace
metadata:
name: iam-example
annotations:
# annotation key is configurable
iam.amazonaws.com/permitted: "arn:aws:iam::123456789012:role/.*"
```

### Add a secret

Add your secret data to your backend. For example, AWS Secrets Manager:

```
aws secretsmanager create-secret --name hello-service/password --secret-string "1234"
```

AWS Parameter Store:

```
aws ssm put-parameter --name "/hello-service/password" --type "String" --value "1234"
```

and then create a `hello-service-external-secret.yml` file:

```yml
apiVersion: "kubernetes-client.io/v1"
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: secretsManager
# optional: specify role to assume when retrieving the data
roleArn: arn:aws:iam::123456789012:role/test-role
data:
- key: hello-service/password
name: password
# optional: specify a template with any additional markup you would like added to the downstream Secret resource.
# This template will be deep merged without mutating any existing fields. For example: you cannot override metadata.name.
template:
metadata:
annotations:
cat: cheese
labels:
dog: farfel
```

```yml
apiVersion: "kubernetes-client.io/v1"
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: systemManager
data:
- key: /hello-service/password
name: password
```

The following IAM policy allows a user or role to access parameters matching `prod-*`.

```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": "ssm:GetParameter",
"Resource": "arn:aws:ssm:us-west-2:123456789012:parameter/prod-*"
}
]
}
```

The IAM policy for Secrets Manager is similar ([see docs](https://docs.aws.amazon.com/mediaconnect/latest/ug/iam-policy-examples-asm-secrets.html)):

```json
{
"Version": "2012-10-17",
"Statement": [
{
"Effect": "Allow",
"Action": [
"secretsmanager:GetResourcePolicy",
"secretsmanager:GetSecretValue",
"secretsmanager:DescribeSecret",
"secretsmanager:ListSecretVersionIds"
],
"Resource": [
"arn:aws:secretsmanager:us-west-2:111122223333:secret:aes128-1a2b3c",
"arn:aws:secretsmanager:us-west-2:111122223333:secret:aes192-4D5e6F",
"arn:aws:secretsmanager:us-west-2:111122223333:secret:aes256-7g8H9i"
]
}
]
}
```

Save the file and run:

```sh
kubectl apply -f hello-service-external-secret.yml
```

Wait a few minutes and verify that the associated `Secret` has been created:

```sh
kubectl get secret hello-service -o=yaml
```

The `Secret` created by the controller should look like:

```yml
apiVersion: v1
kind: Secret
metadata:
name: hello-service
annotations:
cat: cheese
labels:
dog: farfel
type: Opaque
data:
password: MTIzNA==
```

### Create secrets of other types than opaque

You can override `ExternalSecret` type using `template`, for example:

```yaml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-docker
spec:
backendType: systemManager
template:
type: kubernetes.io/dockerconfigjson
data:
- key: /hello-service/hello-docker
name: .dockerconfigjson
```

### Templating

Kubernetes External Secrets supports templating in `ExternalSecret` using [lodash.template](https://lodash.com/docs/4.17.15#template).

Template is applied to all `ExternalSecret.template` sections of the manifest.
Data retrieved from secure backend is available via the `data` variable.
Additonal object `yaml` of instance of [js-yaml](https://github.com/nodeca/js-yaml) is available in `lodash` templates.
It can be leveraged for easier YAML content manipulation.

Templating can be used for:

- Generating K8S `Secret` keys:
- upserting plain text via `ExternalSecret.template.stringData`
- upserting base64 encoded content `ExternalSecret.template.data`
- For creating dynamic labels, annotations and other fields available in K8S `Secret` object.

To demonstrate templating functionality let's assume the secure backend, e.g. Hashicorp Vault, contains the following data

kv/extsec/secret1
kv/extsec/secret2

```json
{
"intKey": 11,
"objKey": {
"strKey": "hello world"
}
}
```

```json
{
"arrKey": [1, 2, 3]
}
```

Then, one could create the following `ExternalSecret`

```yaml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: tmpl-ext-sec
spec:
backendType: vault
data:
- key: kv/data/extsec/secret1
name: s1
- key: kv/data/extsec/secret2
name: s2
kvVersion: 2
template:
data:
file.txt: |
<%= Buffer.from(JSON.stringify(JSON.parse(data.s1).objKey)).toString("base64") %>
metadata:
labels:
label1: <%= JSON.parse(data.s1).intKey %>
label2: <%= JSON.parse(data.s1).objKey.strKey.replace(" ", "-") %>
stringData:
file.yaml: |
<%= yaml.dump(JSON.parse(data.s1)) %>
<% let s2 = JSON.parse(data.s2) %><% s2.arrKey.forEach((e, i) => { %>arr_<%= i %>: <%= e %>
<% }) %>`
vaultMountPoint: kubernetes
vaultRole: demo
```

After applying this `ExternalSecret` to the K8S cluster, the operator will generate following `Secret`

```yaml
apiVersion: v1
data:
file.txt: eyJzdHJLZXkiOiJoZWxsbyB3b3JsZCJ9
file.yaml: aW50S2V5OiAxMQpvYmpLZXk6CiAgc3RyS2V5OiBoZWxsbyB3b3JsZAoKYXJyXzA6IDEKYXJyXzE6IDIKYXJyXzI6IDMKYAo=
s1: eyJpbnRLZXkiOjExLCJvYmpLZXkiOnsic3RyS2V5IjoiaGVsbG8gd29ybGQifX0=
s2: eyJhcnJLZXkiOlsxLDIsM119
kind: Secret
metadata:
name: tmpl-ext-sec
labels:
label1: "11"
label2: hello-world
type: Opaque
```

Resulting `Secret` could be inspected to see that result is generated by `lodash` templating engine

```bash
$ kubectl get secret/tmpl-ext-sec -ogo-template='{{ index .data "s1" | base64decode }}'
{"intKey":11,"objKey":{"strKey":"hello world"}}

$ kubectl get secret/tmpl-ext-sec -ogo-template='{{ index .data "s2" | base64decode }}'
{"arrKey":[1,2,3]}

$ kubectl get secret/tmpl-ext-sec -ogo-template='{{ index .data "file.txt" | base64decode }}'
{"strKey":"hello world"}

$ kubectl get secret/tmpl-ext-sec -ogo-template='{{ index .data "file.yaml" | base64decode }}'
intKey: 11
objKey:
strKey: hello world

arr_0: 1
arr_1: 2
arr_2: 3

$ kubectl get secret/tmpl-ext-sec -ogo-template='{{ .metadata.labels }}'
map[label1:11 label2:hello-world]
```

## Scoping access

### Using Namespace annotation

Enforcing naming conventions for backend keys could be done by using namespace annotations.
By default an `ExternalSecret` may access arbitrary keys from the backend e.g.

```yml
data:
- key: /dev/cluster1/core-namespace/hello-service/password
name: password
```

An enforced naming convention helps to keep the structure tidy and limits the access according
to your naming schema.

Configure the schema as a regular expression in the namespace using an annotation.
This allows `ExternalSecrets` in `core-namespace` only access to secrets that start with
`/dev/cluster1/core-namespace/`:

```yaml
kind: Namespace
metadata:
name: core-namespace
annotations:
# annotation key is configurable
externalsecrets.kubernetes-client.io/permitted-key-name: "/dev/cluster1/core-namespace/.*"
```

### Using ExternalSecret controller config

ExternalSecret config allows scoping the access of kubernetes-external-secrets controller.
This allows deployment of multiple kubernetes-external-secrets instances in the same cluster
and each instance can access a set of predefined namespaces.

To enable this option, set the env var in the controller side to a list of namespaces:

```yaml
env:
WATCHED_NAMESPACES: "default,qa,dev"
```

### Using ExternalSecret config

ExternalSecret manifest allows scoping the access of kubernetes-external-secrets controller.
This allows deployment of multiple kubernetes-external-secrets instances at the same cluster
and each instance can access a set of ExternalSecrets.

To enable this option, set the env var in the controller side:
```yaml
env:
INSTANCE_ID: "dev-team-instance"
```

And in ExternalSecret side:
```yaml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: foo
spec:
controllerId: 'dev-team-instance'
[...]
```

**Please note**

Scoping access by ExternalSecret config provides only a logical separation and it doesn't cover the security aspects.
i.e it assumes that the security side is managed by another component like Kubernetes Network policies
or Open Policy Agent.

## Deprecations

A few properties have changed name overtime, we still maintain backwards compatbility with these but they will eventually be removed, and they are not validated using the CRD validation.

| Old | New |
| ---------------------------- | ----------------------------- |
| `secretDescriptor` | `spec` |
| `spec.type` | `spec.template.type` |
| `spec.properties` | `spec.data` |
| `backendType: secretManager` | `backendType: secretsManager` |

## Backends

kubernetes-external-secrets supports AWS Secrets Manager, AWS System Manager, Akeyless, Hashicorp Vault, Azure Key Vault, Google Secret Manager and Alibaba Cloud KMS Secret Manager.

### AWS Secrets Manager

kubernetes-external-secrets supports both JSON objects ("Secret
key/value" in the AWS console) or strings ("Plaintext" in the AWS
console). Using JSON objects is useful when you need to atomically
update multiple values. For example, when rotating a client
certificate and private key.

When writing an ExternalSecret for a JSON object you must specify the
properties to use. For example, if we add our hello-service
credentials as a single JSON object:

```
aws secretsmanager create-secret --region us-west-2 --name hello-service/credentials --secret-string '{"username":"admin","password":"1234"}'
```

We can declare which properties we want from `hello-service/credentials`:

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: secretsManager
# optional: specify role to assume when retrieving the data
roleArn: arn:aws:iam::123456789012:role/test-role
# optional: specify region
region: us-east-1
data:
- key: hello-service/credentials
name: password
property: password
- key: hello-service/credentials
name: username
property: username
- key: hello-service/credentials
name: password_previous
# Version Stage in Secrets Manager
versionStage: AWSPREVIOUS
property: password
- key: hello-service/credentials
name: password_versioned
# Version ID in Secrets Manager
versionId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
property: password
```

alternatively you can use `dataFrom` and get all the values from `hello-service/credentials`:

`dataFrom` by default retrieves the latest (`AWSCURRENT`) version of the backend secret, if you want to get values in bulk of a specific version, you can use `dataFromWithOptions`:

`data`, `dataFrom` and `dataFromWithOptions` can of course be combined, any naming conflicts will use the last defined.
In the below example `data` takes precedence over `dataFromWithOptions` and `dataFrom`.

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: secretsManager
# optional: specify role to assume when retrieving the data
roleArn: arn:aws:iam::123456789012:role/test-role
# optional: specify region
region: us-east-1
dataFrom:
- hello-service/credentials
dataFromWithOptions:
- key: hello-service/credentials
versionId: xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
data:
- key: hello-service/migration-credentials
name: password
property: password
```

### AWS SSM Parameter Store

You can scrape values from SSM Parameter Store individually or by providing a path to fetch all keys inside.

When fetching all keys by path, you can also recursively scrape all the sub paths (child paths) if you need to. The default is not to scrape child paths.

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: systemManager
# optional: specify role to assume when retrieving the data
roleArn: arn:aws:iam::123456789012:role/test-role
# optional: specify region
region: us-east-1
data:
- key: /foo/name
name: fooName
- path: /extra-people/
recursive: false
```

`data` and `dataFrom` retrieve the latest version of the parameter by default. If you want to get values for a specific version, you can append the version number to the key:

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: systemManager
# optional: specify role to assume when retrieving the data
roleArn: arn:aws:iam::123456789012:role/test-role
# optional: specify region
region: us-east-1
dataFrom:
- hello-service/credentials:3
data:
- key: /foo/name
name: fooName:5
```

### Akeyless Vault

kubernetes-external-secrets supports fetching secrets from [Akeyless Vault](https://www.akeyless.io/), .
You will need to set the following environment variables:

```yml
env:
#akeyless rest-v2 endpoint
AKEYLESS_API_ENDPOINT: https://api.akeyless.io
AKEYLESS_ACCESS_ID:
#AKEYLESS_ACCESS_TYPE can be one of the following: aws_iam/azure_ad/gcp/access_key
AKEYLESS_ACCESS_TYPE:
#AKEYLESS_ACCESS_TYPE_PARAM can be one of the following: gcp-audience/azure-obj-id/access-key
#AKEYLESS_ACCESS_TYPE_PARAM:

```

Once you have kubernetes-external-secrets installed, you can create an external secret with YAML like the following:

```yml
apiVersion: 'kubernetes-client.io/v1'
kind: ExternalSecret
metadata:
name: hello-secret
spec:
backendType: akeyless
data:
- key: path/secret-name
name: password

```

### Hashicorp Vault

kubernetes-external-secrets supports fetching secrets from [Hashicorp Vault](https://www.vaultproject.io/), using the [Kubernetes authentication method](https://www.vaultproject.io/docs/auth/kubernetes).

```yml
env:
VAULT_ADDR: https://vault.domain.tld
DEFAULT_VAULT_MOUNT_POINT: "k8s-auth" # optional, default value to be used if not specified in the ExternalSecret
DEFAULT_VAULT_ROLE: "k8s-auth-role" # optional, default value to be used if not specified in the ExternalSecret
```

You will need to set the `VAULT_ADDR` environment variables so that kubernetes-external-secrets knows which endpoint to connect to, then create `ExternalSecret` definitions as follows:

```yml
apiVersion: "kubernetes-client.io/v1"
kind: ExternalSecret
metadata:
name: hello-vault-service
spec:
backendType: vault
# Your authentication mount point, e.g. "kubernetes"
# Overrides cluster DEFAULT_VAULT_MOUNT_POINT
vaultMountPoint: my-kubernetes-vault-mount-point
# The vault role that will be used to fetch the secrets
# This role will need to be bound to kubernetes-external-secret's ServiceAccount; see Vault's documentation:
# https://www.vaultproject.io/docs/auth/kubernetes.html
# Overrides cluster DEFAULT_VAULT_ROLE
vaultRole: my-vault-role
data:
- name: password
# The full path of the secret to read, as in `vault read secret/data/hello-service/credentials`
key: secret/data/hello-service/credentials
property: password
# Vault values are matched individually. If you have several keys in your Vault secret, you will need to add them all separately
- name: api-key
key: secret/data/hello-service/credentials
property: api-key
```

If you use Vault Namespaces (a Vault Enterprise feature) you can set the namespace to interact with via the `VAULT_NAMESPACE` environment variable.

The Vault token obtained by Kubernetes authentication will be renewed as needed. By default the token will be renewed three poller intervals (POLLER_INTERVAL_MILLISECONDS) before the token TTL expires. The default should be acceptable in most cases but the token renew threshold can also be customized by setting the `VAULT_TOKEN_RENEW_THRESHOLD` environment variable. The token renew threshold value is specified in seconds and tokens with remaining TTL less than this number of seconds will be renewed. In order to minimize token renewal load on the Vault server it is suggested that Kubernetes auth tokens issued by Vault have a TTL of at least ten times the poller interval so that they are renewed less frequently. A longer token TTL results in a lower token renewal load on Vault.

If Vault uses a certificate issued by a self-signed CA you will need to provide that certificate:

```sh
# Create secret with CA
kubectl create secret generic vault-ca --from-file=./ca.pem
```

```yml
# values.yaml
env:
VAULT_ADDR: https://vault.domain.tld
NODE_EXTRA_CA_CERTS: "/usr/local/share/ca-certificates/ca.pem"

filesFromSecret:
certificate-authority:
secret: vault-ca
mountPath: /usr/local/share/ca-certificates
```

### Azure Key Vault

kubernetes-external-secrets supports fetching secrets from [Azure Key vault](https://azure.microsoft.com/en-ca/services/key-vault/)

You will need to set these env vars in the deployment of kubernetes-external-secrets:

- `AZURE_TENANT_ID`
- `AZURE_CLIENT_ID`
- `AZURE_CLIENT_SECRET`

The SP configured will require get and list access policies on the `AZURE_KEYVAULT_NAME`.

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-keyvault-service
spec:
backendType: azureKeyVault
keyVaultName: hello-world
data:
- key: hello-service/credentials
name: password
```

### Alibaba Cloud KMS Secret Manager

kubernetes-external-secrets supports fetching secrets from [Alibaba Cloud KMS Secret Manager](https://www.alibabacloud.com/help/doc-detail/152001.htm)

create secret by using the [aliyun-cli](https://github.com/aliyun/aliyun-cli) command below:

```bash
# you need to configure aliyun-cli with a valid RAM user and proper permission
aliyun kms CreateSecret --SecretName my_secret --SecretData P@ssw0rd --VersionId 001
```

You will need to set these env vars in the deployment of kubernetes-external-secrets:

- `ALICLOUD_ACCESS_KEY_ID`
- `ALICLOUD_ACCESS_KEY_SECRET`
- `ALICLOUD_ENDPOINT`

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: alicloudSecretsManager
# optional: specify role to assume using provided access key ID and access key secret when retrieving the data
roleArn: acs:ram::{UID}:role/demo
data:
- key: hello-credentials1
name: password
- key: hello-credentials2
name: username
# Version Stage in Alibaba Cloud KMS Secrets Manager. Optional, default value is ACSCurrent
versionStage: ACSCurrent
```

### GCP Secret Manager

kubernetes-external-secrets supports fetching secrets from [GCP Secret Manager](https://cloud.google.com/solutions/secrets-management)

The external secret will poll for changes to the secret according to the value set for `POLLER_INTERVAL_MILLISECONDS` in env. Depending on the time interval this is set to you may incur additional charges as Google Secret Manager [charges](https://cloud.google.com/secret-manager/pricing) per a set number of API calls.

A service account is required to grant the controller access to pull secrets.

#### Add a secret

Add your secret data to your backend using GCP SDK :

```
echo -n '{"value": "my-secret-value"}' | gcloud secrets create my-gsm-secret-name --replication-policy="automatic" --data-file=-
```

If the secret needs to be updated :

```
echo -n '{"value": "my-secret-value-with-update"}' | gcloud secrets versions add my-gsm-secret-name --data-file=-
```

##### Deploy kubernetes-external-secrets using Workload Identity

Instructions are here: [Enable Workload Identity](https://cloud.google.com/kubernetes-engine/docs/how-to/workload-identity#enable_workload_identity_on_a_new_cluster). To enable workload identity on an existing cluster (which is not covered in that document), first enable it on the cluster like so:

gcloud container clusters update $CLUSTER_NAME --workload-pool=$PROJECT_NAME.svc.id.goog

Next enable workload metadata config on the node pool in which the pod will run:

gcloud beta container node-pools update $POOL --cluster $CLUSTER_NAME --workload-metadata-from-node=GKE_METADATA_SERVER

If enabling it only for a particular pool, make sure to add any relevant tolerations or affinities:

tolerations:
- key: "name"
operator: "Equal"
effect: "NoExecute"
value: "node-pool-taint"
- key: "name"
operator: "Equal"
effect: "NoSchedule"
value: "node-pool-taint"

affinity:
nodeAffinity:
requiredDuringSchedulingIgnoredDuringExecution:
nodeSelectorTerms:
- matchExpressions:
- key: cloud.google.com/gke-nodepool
operator: In
values:
- node-pool

You can add an annotation which is needed for workload identity by passing it in via Helm:

serviceAccount:
annotations:
iam.gke.io/gcp-service-account: my-secrets-sa@$PROJECT.iam.gserviceaccount.com

Create the policy binding:

gcloud iam service-accounts add-iam-policy-binding --role roles/iam.workloadIdentityUser --member "serviceAccount:$CLUSTER_PROJECT.svc.id.goog[$SECRETS_NAMESPACE/kubernetes-external-secrets]" my-secrets-sa@$PROJECT.iam.gserviceaccount.com

Grant GCP service account access to secrets:

gcloud projects add-iam-policy-binding $PROJECT_ID --member=serviceAccount:my-secrets-sa@$PROJECT.iam.gserviceaccount.com --role=roles/secretmanager.secretAccessor

##### Deploy kubernetes-external-secrets using a service account key

Alternatively you can create and mount a kubernetes secret containing google service account credentials and set the `GOOGLE_APPLICATION_CREDENTIALS` env variable.

Create a Kubernetes secret called gcp-creds with a JSON keyfile from a service account with necessary credentials to access the secrets:

apiVersion: v1
kind: Secret
metadata:
name: mysecret
type: Opaque
stringData:
gcp-creds.json: |-
$KEYFILE_CONTENT

Uncomment `GOOGLE_APPLICATION_CREDENTIALS` in the values file as well as the following section:

env:
AWS_REGION: us-west-2
POLLER_INTERVAL_MILLISECONDS: 10000 # Caution, setting this frequency may incur additional charges on some platforms
LOG_LEVEL: info
METRICS_PORT: 3001
VAULT_ADDR: http://127.0.0.1:8200
GOOGLE_APPLICATION_CREDENTIALS: /app/gcp-creds/gcp-creds.json

filesFromSecret:
gcp-creds:
secret: gcp-creds
mountPath: /app/gcp-creds

This will mount the secret at `/app/gcp-creds/gcp-creds.json` and make it available via the `GOOGLE_APPLICATION_CREDENTIALS` environment variable.

#### Usage

Once you have kubernetes-external-secrets installed, you can create an external secret with YAML like the following:

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: gcp-secrets-manager-example # name of the k8s external secret and the k8s secret
spec:
backendType: gcpSecretsManager
projectId: my-gsm-secret-project
data:
- key: my-gsm-secret-name # name of the GCP secret
name: my-kubernetes-secret-name # key name in the k8s secret
version: latest # version of the GCP secret
property: value # name of the field in the GCP secret
```

The field "key" is the name of the secret in Google Secret Manager. The field "name" is the name of the Kubernetes secret this external secret will generate. The metadata "name" field is the name of the external secret in Kubernetes.

To retrieve external secrets, you can use the following command:

kubectl get externalsecrets -n $NAMESPACE

To retrieve the secrets themselves, you can use the regular:

kubectl get secrets -n $NAMESPACE

To retrieve an individual secret's content, use the following where "mysecret" is the key to the secret content under the "data" field:

kubectl get secret my-secret -o 'go-template={{index .data "mysecret"}}' | base64 -D

The secrets will persist even if the helm installation is removed, although they will no longer sync to Google Secret Manager.

### IBM Cloud Secrets Manager

kubernetes-external-secrets supports fetching secrets from [IBM Cloud Secrets Manager](https://cloud.ibm.com/catalog/services/secrets-manager).

Create username_password secret by using the [UI, CLI or API](https://cloud.ibm.com/docs/secrets-manager?topic=secrets-manager-user-credentials).
The CLI option is illustrated below:

```bash
# You need to configure ibm cloud cli with a valid endpoint.
# If you're using plug-in version 0.0.8 or later, export the following variable.
export SECRETS_MANAGER_URL=https://{instanceid}.{region}.secrets-manager.appdomain.cloud

# If you're using plug-in version 0.0.6 or earlier, export the following variable.
export IBM_CLOUD_SECRETS_MANAGER_API_URL=https://{instance_ID}.{region}.secrets-manager.appdomain.cloud

ibmcloud secrets-manager secret-create --secret-type username_password \
--metadata '{"collection_type": "application/vnd.ibm.secrets-manager.secret+json", "collection_total": 1}' \
--resources '[{"name": "example-username-password-secret","description": "Extended description for my secret.","username": "user123","password": "cloudy-rainy-coffee-book"}]'
```

You will need to set these env vars in the deployment of kubernetes-external-secrets:

- `IBM_CLOUD_SECRETS_MANAGER_API_APIKEY`
- `IBM_CLOUD_SECRETS_MANAGER_API_ENDPOINT`
- `IBM_CLOUD_SECRETS_MANAGER_API_AUTH_TYPE`

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: ibmcloud-secrets-manager-example
spec:
backendType: ibmcloudSecretsManager
data:
# The guid id of the secret
- key:
name: username
property: username
secretType: username_password
```

Alternately, you can use `keyByName` on the spec to interpret keys as secret names, instead of IDs.
Using names is slightly less efficient than using IDs, but it makes your ExternalSecrets more robust, as they are not tied to a particular instance of a secret in a particular instance of Secrets Manager:

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: ibmcloud-secrets-manager-example
spec:
backendType: ibmcloudSecretsManager
keyByName: true
data:
# The name of the secret
- key: my-creds
name: username
property: username
secretType: username_password
```

## Binary Secrets

Most backends do not treat binary secrets any differently than text secrets. Since you typically store a binary secret as a base64-encoded string in the backend, you need to explicitly let the ExternalSecret know that the secret is binary, otherwise it will be encoded in base64 again.
You can do that with the `isBinary` field on the key. This is necessary for certificates and other secret binary files.

```yml
apiVersion: kubernetes-client.io/v1
kind: ExternalSecret
metadata:
name: hello-service
spec:
backendType: anySupportedBackend
# ...
data:
- key: hello-service/archives/secrets_zip
name: secrets.zip
isBinary: true # Default: false
# also works with `property`
- key: hello-service/certificates
name: cert.p12
property: cert.p12
isBinary: true
```

AWS Secrets Manager is a notable exception to this. If you create/update a secret using [SecretBinary](https://docs.aws.amazon.com/secretsmanager/latest/apireference/API_CreateSecret.html#API_CreateSecret_RequestSyntax) parameter of the API, then AWS API will return the secret data as `SecretBinary` in the response and ExternalSecret will handle it accordingly. In that case, you do not need to use the `isBinary` field.

Note that `SecretBinary` parameter is not available when using the AWS Secrets Manager console. For any binary secrets (represented by a base64-encoded strings) created/updated via the AWS console, or stored in key-value pairs instead of text strings, you can just use the `isBinary` field explicitly as above.

## Metrics

kubernetes-external-secrets exposes the following metrics over a prometheus endpoint:

| Metric | Type | Description | Example |
| -------------------------------------------------- | ------- | --------------------------------------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------- |
| `kubernetes_external_secrets_sync_calls_count` | Counter | Number of sync operations by backend, secret name and status | `kubernetes_external_secrets_sync_calls_count{name="foo",namespace="example",backend="foo",status="success"} 1` |
| `kubernetes_external_secrets_last_sync_call_state` | Gauge | State of last sync call of external secret, where -1 means the last sync_call was an error and 1 means the last sync_call was a success | `kubernetes_external_secrets_last_sync_call_state{name="foo",namespace="example",backend="foo"} 1` |

## Development

[Minikube](https://kubernetes.io/docs/tasks/tools/install-minikube/) is a tool that makes it easy to run a Kubernetes cluster locally.

Start minikube and the daemon. This creates the `CustomerResourceDefinition`, and starts to process `ExternalSecrets`:

```sh
minikube start

npm run nodemon
```

### Development with localstack

[Localstack](https://github.com/localstack/localstack) mocks AWS services locally so you can test without connecting to AWS.

Run localstack in a separate terminal window

```sh
npm run localstack
```

Start minikube as above

```sh
minikube start
```

Run the daemon with localstack

```sh
npm run local
```

Add secrets using the AWS cli (example)

```sh
AWS_ACCESS_KEY_ID=foobar AWS_SECRET_ACCESS_KEY=foobar aws --region=us-west-2 --endpoint-url=http://localhost:4584 secretsmanager create-secret --name hello-service/password --secret-string "1234"
```

## Related projects

### khcheck-external-secrets

[khcheck-external-secrets](https://github.com/Nick-Triller/khcheck-external-secrets) is a
[kuberhealthy](https://github.com/Comcast/kuberhealthy) check that monitors if the external secrets operator is functional.