Azure App Configuration Kubernetes Provider reference
The following reference outlines the properties supported by the Azure App Configuration Kubernetes Provider v2.0.0
. See release notes for more information on the change.
Properties
An AzureAppConfigurationProvider
resource has the following top-level child properties under the spec
. Either endpoint
or connectionStringReference
has to be specified.
Name | Description | Required | Type |
---|---|---|---|
endpoint | The endpoint of Azure App Configuration, which you would like to retrieve the key-values from. | alternative | string |
connectionStringReference | The name of the Kubernetes Secret that contains Azure App Configuration connection string. | alternative | string |
replicaDiscoveryEnabled | The setting that determines whether replicas of Azure App Configuration are automatically discovered and used for failover. If the property is absent, a default value of true is used. |
false | bool |
target | The destination of the retrieved key-values in Kubernetes. | true | object |
auth | The authentication method to access Azure App Configuration. | false | object |
configuration | The settings for querying and processing key-values in Azure App Configuration. | false | object |
secret | The settings for Key Vault references in Azure App Configuration. | conditional | object |
featureFlag | The settings for feature flags in Azure App Configuration. | false | object |
The spec.target
property has the following child property.
Name | Description | Required | Type |
---|---|---|---|
configMapName | The name of the ConfigMap to be created. | true | string |
configMapData | The setting that specifies how the retrieved data should be populated in the generated ConfigMap. | false | object |
If the spec.target.configMapData
property is not set, the generated ConfigMap is populated with the list of key-values retrieved from Azure App Configuration, which allows the ConfigMap to be consumed as environment variables. Update this property if you wish to consume the ConfigMap as a mounted file. This property has the following child properties.
Name | Description | Required | Type |
---|---|---|---|
type | The setting that indicates how the retrieved data is constructed in the generated ConfigMap. The allowed values include default , json , yaml and properties . |
optional | string |
key | The key name of the retrieved data when the type is set to json , yaml or properties . Set it to the file name if the ConfigMap is set up to be consumed as a mounted file. |
conditional | string |
separator | The delimiter that is used to output the ConfigMap data in hierarchical format when the type is set to json or yaml . The separator is empty by default and the generated ConfigMap contains key-values in their original form. Configure this setting only if the configuration file loader used in your application can't load key-values without converting them to the hierarchical format. |
optional | string |
The spec.auth
property isn't required if the connection string of your App Configuration store is provided by setting the spec.connectionStringReference
property. Otherwise, one of the identities, service principal, workload identity, or managed identity, is used for authentication. The spec.auth
has the following child properties. Only one of them should be specified. If none of them are set, the system-assigned managed identity of the virtual machine scale set is used.
Name | Description | Required | Type |
---|---|---|---|
servicePrincipalReference | The name of the Kubernetes Secret that contains the credentials of a service principal. The secret must be in the same namespace as the Kubernetes provider. | false | string |
workloadIdentity | The settings for using workload identity. | false | object |
managedIdentityClientId | The client ID of user-assigned managed identity of virtual machine scale set. | false | string |
The spec.auth.workloadIdentity
property has the following child property.
Name | Description | Required | Type |
---|---|---|---|
serviceAccountName | The name of the service account associated with the workload identity. | true | string |
The spec.configuration
has the following child properties.
Name | Description | Required | Type |
---|---|---|---|
selectors | The list of selectors for key-value filtering. | false | object array |
trimKeyPrefixes | The list of key prefixes to be trimmed. | false | string array |
refresh | The settings for refreshing key-values from Azure App Configuration. If the property is absent, key-values from Azure App Configuration are not refreshed. | false | object |
If the spec.configuration.selectors
property isn't set, all key-values with no label are downloaded. It contains an array of selector objects, which have the following child properties. Note that the key-values of the last selector take precedence and override any overlapping keys from the previous selectors.
Name | Description | Required | Type |
---|---|---|---|
keyFilter | The key filter for querying key-values. This property and the snapshotName property should not be set at the same time. |
alternative | string |
labelFilter | The label filter for querying key-values. This property and the snapshotName property should not be set at the same time. |
false | string |
snapshotName | The name of a snapshot from which key-values are loaded. This property should not be used in conjunction with other properties. | alternative | string |
The spec.configuration.refresh
property has the following child properties.
Name | Description | Required | Type |
---|---|---|---|
enabled | The setting that determines whether key-values from Azure App Configuration is automatically refreshed. If the property is absent, a default value of false is used. |
false | bool |
monitoring | The key-values monitored for change detection, aka sentinel keys. The key-values from Azure App Configuration are refreshed only if at least one of the monitored key-values is changed. | true | object |
interval | The interval at which the key-values are refreshed from Azure App Configuration. It must be greater than or equal to 1 second. If the property is absent, a default value of 30 seconds is used. | false | duration string |
The spec.configuration.refresh.monitoring.keyValues
is an array of objects, which have the following child properties.
Name | Description | Required | Type |
---|---|---|---|
key | The key of a key-value. | true | string |
label | The label of a key-value. | false | string |
The spec.secret
property has the following child properties. It is required if any Key Vault references are expected to be downloaded. To learn more about the support for Kubernetes built-in types of Secrets, see Types of Secret.
Name | Description | Required | Type |
---|---|---|---|
target | The destination of the retrieved secrets in Kubernetes. | true | object |
auth | The authentication method to access Key Vaults. | false | object |
refresh | The settings for refreshing data from Key Vaults. If the property is absent, data from Key Vaults is not refreshed unless the corresponding Key Vault references are reloaded. | false | object |
The spec.secret.target
property has the following child property.
Name | Description | Required | Type |
---|---|---|---|
secretName | The name of the Kubernetes Secret to be created. | true | string |
If the spec.secret.auth
property isn't set, the system-assigned managed identity is used. It has the following child properties.
Name | Description | Required | Type |
---|---|---|---|
servicePrincipalReference | The name of the Kubernetes Secret that contains the credentials of a service principal used for authentication with Key Vaults that don't have individual authentication methods specified. | false | string |
workloadIdentity | The settings of the workload identity used for authentication with Key Vaults that don't have individual authentication methods specified. It has the same child property as spec.auth.workloadIdentity . |
false | object |
managedIdentityClientId | The client ID of a user-assigned managed identity of virtual machine scale set used for authentication with Key Vaults that don't have individual authentication methods specified. | false | string |
keyVaults | The authentication methods for individual Key Vaults. | false | object array |
The authentication method of each Key Vault can be specified with the following properties. One of managedIdentityClientId
, servicePrincipalReference
or workloadIdentity
must be provided.
Name | Description | Required | Type |
---|---|---|---|
uri | The URI of a Key Vault. | true | string |
servicePrincipalReference | The name of the Kubernetes Secret that contains the credentials of a service principal used for authentication with a Key Vault. | false | string |
workloadIdentity | The settings of the workload identity used for authentication with a Key Vault. It has the same child property as spec.auth.workloadIdentity . |
false | object |
managedIdentityClientId | The client ID of a user-assigned managed identity of virtual machine scale set used for authentication with a Key Vault. | false | string |
The spec.secret.refresh
property has the following child properties.
Name | Description | Required | Type |
---|---|---|---|
enabled | The setting that determines whether data from Key Vaults is automatically refreshed. If the property is absent, a default value of false is used. |
false | bool |
interval | The interval at which the data is refreshed from Key Vault. It must be greater than or equal to 1 minute. The Key Vault refresh is independent of the App Configuration refresh configured via spec.configuration.refresh . |
true | duration string |
The spec.featureFlag
property has the following child properties. It is required if any feature flags are expected to be downloaded.
Name | Description | Required | Type |
---|---|---|---|
selectors | The list of selectors for feature flag filtering. | false | object array |
refresh | The settings for refreshing feature flags from Azure App Configuration. If the property is absent, feature flags from Azure App Configuration are not refreshed. | false | object |
If the spec.featureFlag.selectors
property isn't set, feature flags are not downloaded. It contains an array of selector objects, which have the following child properties. Note that the feature flags of the last selector take precedence and override any overlapping keys from the previous selectors.
Name | Description | Required | Type |
---|---|---|---|
keyFilter | The key filter for querying feature flags. This property and the snapshotName property should not be set at the same time. |
alternative | string |
labelFilter | The label filter for querying feature flags. This property and the snapshotName property should not be set at the same time. |
false | string |
snapshotName | The name of a snapshot from which feature flags are loaded. This property should not be used in conjunction with other properties. | alternative | string |
The spec.featureFlag.refresh
property has the following child properties.
Name | Description | Required | Type |
---|---|---|---|
enabled | The setting that determines whether feature flags from Azure App Configuration are automatically refreshed. If the property is absent, a default value of false is used. |
false | bool |
interval | The interval at which the feature flags are refreshed from Azure App Configuration. It must be greater than or equal to 1 second. If the property is absent, a default value of 30 seconds is used. | false | duration string |
Installation
Use the following helm install
command to install the Azure App Configuration Kubernetes Provider. See helm-values.yaml for the complete list of parameters and their default values. You can override the default values by passing the --set
flag to the command.
helm install azureappconfiguration.kubernetesprovider \
oci://mcr.microsoft.com/azure-app-configuration/helmchart/kubernetes-provider \
--namespace azappconfig-system \
--create-namespace
Autoscaling
By default, autoscaling is disabled. However, if you have multiple AzureAppConfigurationProvider
resources to produce multiple ConfigMaps/Secrets, you can enable horizontal pod autoscaling by setting autoscaling.enabled
to true
.
helm install azureappconfiguration.kubernetesprovider \
oci://mcr.microsoft.com/azure-app-configuration/helmchart/kubernetes-provider \
--namespace azappconfig-system \
--create-namespace
--set autoscaling.enabled=true
Data collection
The software may collect information about you and your use of the software and send it to Microsoft. Microsoft may use this information to provide services and improve our products and services. You may turn off the telemetry by setting the requestTracing.enabled=false
while installing the Azure App Configuration Kubernetes Provider. There are also some features in the software that may enable you and Microsoft to collect data from users of your applications. If you use these features, you must comply with applicable law, including providing appropriate notices to users of your applications together with a copy of Microsoft’s privacy statement. Our privacy statement is located at https://go.microsoft.com/fwlink/?LinkID=824704. You can learn more about data collection and use in the help documentation and our privacy statement. Your use of the software operates as your consent to these practices.
Examples
Authentication
Use system-assigned managed identity of virtual machine scale set
Enable the system-assigned managed identity in the virtual machine scale set used by the Azure Kubernetes Service (AKS) cluster.
Grant the system-assigned managed identity App Configuration Data Reader role in Azure App Configuration.
Deploy the following sample
AzureAppConfigurationProvider
resource to the AKS cluster.apiVersion: azconfig.io/v1 kind: AzureAppConfigurationProvider metadata: name: appconfigurationprovider-sample spec: endpoint: <your-app-configuration-store-endpoint> target: configMapName: configmap-created-by-appconfig-provider
Use user-assigned managed identity of virtual machine scale set
Create a user-assigned managed identity and note down its client ID after creation.
Assign the user-assigned managed identity to the virtual machine scale set used by the Azure Kubernetes Service (AKS) cluster.
Grant the user-assigned managed identity App Configuration Data Reader role in Azure App Configuration.
Set the
spec.auth.managedIdentityClientId
property to the client ID of the user-assigned managed identity in the following sampleAzureAppConfigurationProvider
resource and deploy it to the AKS cluster.apiVersion: azconfig.io/v1 kind: AzureAppConfigurationProvider metadata: name: appconfigurationprovider-sample spec: endpoint: <your-app-configuration-store-endpoint> target: configMapName: configmap-created-by-appconfig-provider auth: managedIdentityClientId: <your-managed-identity-client-id>
Use service principal
Grant the service principal App Configuration Data Reader role in Azure App Configuration.
Create a Kubernetes Secret in the same namespace as the
AzureAppConfigurationProvider
resource and add azure_client_id, azure_client_secret, and azure_tenant_id of the service principal to the Secret.Set the
spec.auth.servicePrincipalReference
property to the name of the Secret in the following sampleAzureAppConfigurationProvider
resource and deploy it to the Kubernetes cluster.apiVersion: azconfig.io/v1 kind: AzureAppConfigurationProvider metadata: name: appconfigurationprovider-sample spec: endpoint: <your-app-configuration-store-endpoint> target: configMapName: configmap-created-by-appconfig-provider auth: servicePrincipalReference: <your-service-principal-secret-name>
Use workload identity
Enable Workload Identity on the Azure Kubernetes Service (AKS) cluster.
Get the OIDC issuer URL of the AKS cluster.
Create a user-assigned managed identity and note down its client ID, tenant ID, name, and resource group.
Grant the user-assigned managed identity App Configuration Data Reader role in Azure App Configuration.
Create a service account by adding a YAML file (e.g., serviceAccount.yaml) with the following content to the directory containing your AKS deployment files. The service account will be created when you apply all your deployment changes to your AKS cluster (e.g., using
kubectl apply
). Replace<your-managed-identity-client-id>
with the client ID and<your-managed-identity-tenant-id>
with the tenant ID of the user-assigned managed identity that has just been created. Replace<your-service-account-name>
with your preferred name.apiVersion: v1 kind: ServiceAccount metadata: name: <your-service-account-name> annotations: azure.workload.identity/client-id: <your-managed-identity-client-id> azure.workload.identity/tenant-id: <your-managed-identity-tenant-id>
Create a federated identity credential for the user-assigned managed identity using the Azure CLI. Replace
<user-assigned-identity-name>
with the name and<resource-group>
with the resource group of the newly created user-assigned managed identity. Replace<aks-oidc-issuer>
with the OIDC issuer URL of the AKS cluster. Replace<your-service-account-name>
with the name of the newly created service account. Replace<federated-identity-credential-name>
with your preferred name for the federated identity credential.az identity federated-credential create --name "<federated-identity-credential-name>" --identity-name "<user-assigned-identity-name>" --resource-group "<resource-group>" --issuer "<aks-oidc-issuer>" --subject system:serviceaccount:default:<your-service-account-name> --audience api://AzureADTokenExchange
Note that the subject of the federated identity credential should follow this format:
system:serviceaccount:<service-account-namespace>:<service-account-name>
.Set the
spec.auth.workloadIdentity.serviceAccountName
property to the name of the service account in the following sampleAzureAppConfigurationProvider
resource. Be sure that theAzureAppConfigurationProvider
resource and the service account are in the same namespace.apiVersion: azconfig.io/v1 kind: AzureAppConfigurationProvider metadata: name: appconfigurationprovider-sample spec: endpoint: <your-app-configuration-store-endpoint> target: configMapName: configmap-created-by-appconfig-provider auth: workloadIdentity: serviceAccountName: <your-service-account-name>
Use connection string
Create a Kubernetes Secret in the same namespace as the
AzureAppConfigurationProvider
resource and add Azure App Configuration connection string with key azure_app_configuration_connection_string in the Secret.Set the
spec.connectionStringReference
property to the name of the Secret in the following sampleAzureAppConfigurationProvider
resource and deploy it to the Kubernetes cluster.apiVersion: azconfig.io/v1 kind: AzureAppConfigurationProvider metadata: name: appconfigurationprovider-sample spec: connectionStringReference: <your-connection-string-secret-name> target: configMapName: configmap-created-by-appconfig-provider
Key-value selection
Use the selectors
property to filter the key-values to be downloaded from Azure App Configuration.
The following sample downloads all key-values with no label.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
In following example, two selectors are used to retrieve two sets of key-values, each with unique labels. It's important to note that the values of the last selector take precedence and override any overlapping keys from the previous selectors.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configuration:
selectors:
- keyFilter: app1*
labelFilter: common
- keyFilter: app1*
labelFilter: development
A snapshot can be used alone or together with other key-value selectors. In the following sample, you load key-values of common configuration from a snapshot and then override some of them with key-values for development.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configuration:
selectors:
- snapshotName: app1_common_configuration
- keyFilter: app1*
labelFilter: development
Key prefix trimming
The following sample uses the trimKeyPrefixes
property to trim two prefixes from key names before adding them to the generated ConfigMap.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configuration:
trimKeyPrefixes: [prefix1, prefix2]
Configuration refresh
When you make changes to your data in Azure App Configuration, you might want those changes to be refreshed automatically in your Kubernetes cluster. It's common to update multiple key-values, but you don't want the cluster to pick up a change midway through the update. To maintain configuration consistency, you can use a key-value to signal the completion of your update. This key-value is known as the sentinel key. The Kubernetes provider can monitor this key-value, and the ConfigMap and Secret will only be regenerated with updated data once a change is detected in the sentinel key.
In the following sample, a key-value named app1_sentinel
is polled every minute, and the configuration is refreshed whenever changes are detected in the sentinel key.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configuration:
selectors:
- keyFilter: app1*
labelFilter: common
refresh:
enabled: true
interval: 1m
monitoring:
keyValues:
- key: app1_sentinel
label: common
Key Vault references
Authentication
In the following sample, one Key Vault is authenticated with a service principal, while all other Key Vaults are authenticated with a user-assigned managed identity.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configuration:
selectors:
- keyFilter: app1*
secret:
target:
secretName: secret-created-by-appconfig-provider
auth:
managedIdentityClientId: <your-user-assigned-managed-identity-client-id>
keyVaults:
- uri: <your-key-vault-uri>
servicePrincipalReference: <name-of-secret-containing-service-principal-credentials>
Types of Secret
Two Kubernetes built-in types of Secrets, Opaque and TLS, are currently supported. Secrets resolved from Key Vault references are saved as the Opaque Secret type by default. If you have a Key Vault reference to a certificate and want to save it as the TLS Secret type, you can add a tag with the following name and value to the Key Vault reference in Azure App Configuration. By doing so, a Secret with the kubernetes.io/tls
type will be generated and named after the key of the Key Vault reference.
Name | Value |
---|---|
.kubernetes.secret.type | kubernetes.io/tls |
Refresh of secrets from Key Vault
Refreshing secrets from Key Vaults usually requires reloading the corresponding Key Vault references from Azure App Configuration. However, with the spec.secret.refresh
property, you can refresh the secrets from Key Vault independently. This is especially useful for ensuring that your workload automatically picks up any updated secrets from Key Vault during secret rotation. Note that to load the latest version of a secret, the Key Vault reference must not be a versioned secret.
The following sample refreshes all non-versioned secrets from Key Vault every hour.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configuration:
selectors:
- keyFilter: app1*
labelFilter: common
secret:
target:
secretName: secret-created-by-appconfig-provider
auth:
managedIdentityClientId: <your-user-assigned-managed-identity-client-id>
refresh:
enabled: true
interval: 1h
Feature Flags
In the following sample, feature flags with keys starting with app1
and labels equivalent to common
are downloaded and refreshed every 10 minutes. Note that to populate feature flags in the generated ConfigMap, the configMapData.type
property must be json
or yaml
.
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
configMapData:
type: json
key: appSettings.json
featureFlag:
selectors:
- keyFilter: app1*
labelFilter: common
refresh:
enabled: true
interval: 10m
ConfigMap Consumption
Applications running in Kubernetes typically consume the ConfigMap either as environment variables or as configuration files. If the configMapData.type
property is absent or is set to default, the ConfigMap is populated with the itemized list of data retrieved from Azure App Configuration, which can be easily consumed as environment variables. If the configMapData.type
property is set to json, yaml or properties, data retrieved from Azure App Configuration is grouped into one item with key name specified by the configMapData.key
property in the generated ConfigMap, which can be consumed as a mounted file.
The following examples show how the data is populated in the generated ConfigMap with different settings of the configMapData.type
property.
Assuming an App Configuration store has these key-values:
key | value |
---|---|
key1 | value1 |
key2 | value2 |
key3 | value3 |
And the configMapData.type
property is absent or set to default
,
apiVersion: azconfig.io/v1
kind: AzureAppConfigurationProvider
metadata:
name: appconfigurationprovider-sample
spec:
endpoint: <your-app-configuration-store-endpoint>
target:
configMapName: configmap-created-by-appconfig-provider
The generated ConfigMap is populated with the following data:
data:
key1: value1
key2: value2
key3: value3