Doppler

Doppler SecretOps Platform

Sync secrets from the Doppler SecretOps Platform to Kubernetes using the External Secrets Operator.

Authentication

Doppler Service Tokens are recommended as they restrict access to a single config.

NOTE: Doppler Personal Tokens are also supported but require project and config to be set on the SecretStore or ClusterSecretStore.

Create the Doppler Token secret by opening the Doppler dashboard and navigating to the desired Project and Config, then create a new Service Token from the Access tab:

Create the Doppler Token Kubernetes secret with your Service Token value:

HISTIGNORE='*kubectl*' kubectl create secret generic \
    doppler-token-auth-api \
    --from-literal dopplerToken="dp.st.xxxx"

Then to create a generic SecretStore:

apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
  name: doppler-auth-api
spec:
  provider:
    doppler:
      auth:
        secretRef:
          dopplerToken:
            name: doppler-token-auth-api
            key: dopplerToken

NOTE: In case of a ClusterSecretStore, be sure to set namespace in secretRef.dopplerToken.

Use Cases

The Doppler provider allows for a wide range of use cases:

1. Fetch
2. Fetch all
3. Filter
4. JSON secret
5. Name transformer
6. Download

Let's explore each use case using a fictional auth-api Doppler project.

1. Fetch

To sync one or more individual secrets:

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: auth-api-db-url
spec:
  secretStoreRef:
    kind: SecretStore
    name: doppler-auth-api

  target:
    name: auth-api-db-url

  data:
    - secretKey: DB_URL
      remoteRef:
        key: DB_URL

2. Fetch all

To sync every secret from a config:

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: auth-api-all
spec:
  secretStoreRef:
    kind: SecretStore
    name: doppler-auth-api

  target:
    name: auth-api-all

  dataFrom:
    - find:
        name:
          regexp: .*

3. Filter

To filter secrets by path (path prefix), name (regular expression) or a combination of both:

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: auth-api-db
spec:
  secretStoreRef:
    kind: SecretStore
    name: doppler-auth-api

  target:
    name: auth-api-db

  dataFrom:
    - find:
        path: DB_

4. JSON secret

To parse a JSON secret to its key-value pairs:

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: auth-api-sa-json
spec:
  secretStoreRef:
    kind: SecretStore
    name: doppler-auth-api

  target:
    name: auth-api-sa-json

  dataFrom:
    - extract:
        key: SA_JSON

5. Name transformer

Name transformers format keys from Doppler's UPPER_SNAKE_CASE to one of the following alternatives:

• upper-camel
• camel
• lower-snake
• tf-var
• dotnet-env
• lower-kebab

Name transformers require a specifically configured SecretStore:

apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
  name: doppler-auth-api-dotnet-env
spec:
  provider:
    doppler:
      auth:
        secretRef:
          dopplerToken:
            name: doppler-token-auth-api
      nameTransformer: dotnet-env

Then an ExternalSecret referencing the SecretStore:

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: doppler-auth-api-dotnet-env
spec:
  secretStoreRef:
    kind: SecretStore
    name: doppler-auth-api-dotnet-env

  target:
    name: doppler-auth-api-dotnet-env
    creationPolicy: Owner

  dataFrom:
    - find:
        name:
          regexp: .*

6. Download

A single DOPPLER_SECRETS_FILE key is set where the value is the secrets downloaded in one of the following formats:

• json
• dotnet-json
• env
• env-no-quotes
• yaml

Downloading secrets requires a specifically configured SecretStore:

apiVersion: external-secrets.io/v1beta1
kind: SecretStore
metadata:
  name: doppler-auth-api-json-file
spec:
  provider:
    doppler:
      auth:
        secretRef:
          dopplerToken:
            name: doppler-token-auth-api
            key: dopplerToken
      format: json

Then an ExternalSecret referencing the SecretStore:

apiVersion: external-secrets.io/v1beta1
kind: ExternalSecret
metadata:
  name: auth-api-json-file
spec:
  secretStoreRef:
    kind: SecretStore
    name: doppler-auth-api-json-file

  target:
    name: auth-api-json-file

  dataFrom:
    - find:
        path: DOPPLER_SECRETS_FILE