Configure settings for the Config Server for Spring component in Azure Container Apps
Config Server for Spring provides a centralized location to make configuration data available to multiple applications. Use the following guidance to learn how to configure and manage your Config Server for Spring component.
Show
You can view the details of an individual component by name using the show
command.
Before you run the following command, replace placeholders surrounded by <>
with your values.
az containerapp env java-component config-server-for-spring show \
--environment <ENVIRONMENT_NAME> \
--resource-group <RESOURCE_GROUP> \
--name <JAVA_COMPONENT_NAME>
List
You can list all registered Java components using the list
command.
Before you run the following command, replace placeholders surrounded by <>
with your values.
az containerapp env java-component list \
--environment <ENVIRONMENT_NAME> \
--resource-group <RESOURCE_GROUP>
Bind
Use the --bind
parameter of the update
command to create a connection between the Config Server for Spring component and your container app.
Before you run the following command, replace placeholders surrounded by <>
with your values.
az containerapp update \
--name <CONTAINER_APP_NAME> \
--resource-group <RESOURCE_GROUP> \
--bind <JAVA_COMPONENT_NAME>
Unbind
To break the connection between your container app and the Config Server for Spring component, use the --unbind
parameter of the update
command.
Before you run the following command, replace placeholders surrounded by <>
with your values.
az containerapp update \
--name <CONTAINER_APP_NAME> \
--unbind <JAVA_COMPONENT_NAME> \
--resource-group <RESOURCE_GROUP>
Configuration options
The az containerapp update
command uses the --configuration
parameter to control how the Config Server for Spring is configured. You can use multiple parameters at once as long as they're separated by a space. You can find more details in Spring Cloud Config Server docs.
The following table lists the different configuration values available.
Git backend configurations
Name | Description |
---|---|
spring.cloud.config.server.git.uri spring.cloud.config.server.git.repos.{repoName}.uri |
URI of remote repository. |
spring.cloud.config.server.git.username spring.cloud.config.server.git.repos.{repoName}.username |
Username for authentication with remote repository. |
spring.cloud.config.server.git.password spring.cloud.config.server.git.repos.{repoName}.password |
Password for authentication with remote repository. |
spring.cloud.config.server.git.search-paths spring.cloud.config.server.git.repos.{repoName}.search-paths |
Search paths to use within local working copy. By default searches only the root. |
spring.cloud.config.server.git.force-pull spring.cloud.config.server.git.repos.{repoName}.force-pull |
Flag to indicate that the repository should force pull. If true discard any local changes and take from remote repository. |
spring.cloud.config.server.git.default-label spring.cloud.config.server.git.repos.{repoName}.default-label |
The default label used for Git is main. If you do not set spring.cloud.config.server.git.default-label and a branch named main does not exist, the config server will by default also try to checkout a branch named master. If you would like to disable the fallback branch behavior you can set spring.cloud.config.server.git.tryMasterBranch to false. |
spring.cloud.config.server.git.try-master-branch spring.cloud.config.server.git.repos.{repoName}.try-master-branch |
The config server will by default try to checkout a branch named master. |
spring.cloud.config.server.git.skip-ssl-validation spring.cloud.config.server.git.repos.{repoName}.skip-ssl-validation |
The configuration server’s validation of the Git server’s SSL certificate can be disabled by setting the git.skipSslValidation property to true. |
spring.cloud.config.server.git.clone-on-start spring.cloud.config.server.git.repos.{repoName}.clone-on-start |
Flag to indicate that the repository should be cloned on startup (not on demand). Generally leads to slower startup but faster first query. |
spring.cloud.config.server.git.timeout spring.cloud.config.server.git.repos.{repoName}.timeout |
Timeout (in seconds) for obtaining HTTP or SSH connection (if applicable). Default 5 seconds. |
spring.cloud.config.server.git.refresh-rate spring.cloud.config.server.git.repos.{repoName}.refresh-rate |
How often the config server will fetch updated configuration data from your Git backend. |
spring.cloud.config.server.git.private-key spring.cloud.config.server.git.repos.{repoName}.private-key |
Valid SSH private key. Must be set if ignore-local-ssh-settings is true and Git URI is SSH format. |
spring.cloud.config.server.git.host-key spring.cloud.config.server.git.repos.{repoName}.host-key |
Valid SSH host key. Must be set if host-key-algorithm is also set. |
spring.cloud.config.server.git.host-key-algorithm spring.cloud.config.server.git.repos.{repoName}.host-key-algorithm |
One of ssh-dss, ssh-rsa, ssh-ed25519, ecdsa-sha2-nistp256, ecdsa-sha2-nistp384, or ecdsa-sha2-nistp521. Must be set if host-key is also set. |
spring.cloud.config.server.git.strict-host-key-checking spring.cloud.config.server.git.repos.{repoName}.strict-host-key-checking |
true or false. If false, ignore errors with host key. |
spring.cloud.config.server.git.repos.{repoName} |
URI of remote repository. |
spring.cloud.config.server.git.repos.{repoName}.pattern |
The pattern format is a comma-separated list of {application}/{profile} names with wildcards. If {application}/{profile} does not match any of the patterns, it uses the default URI defined under. |
Common configurations
logging related configurations
- logging.level.*
- logging.group.*
- Any other configurations under logging.* namespace should be forbidden, for example, writing log files by using
logging.file
should be forbidden.
spring.cloud.config.server.overrides
- Extra map for a property source to be sent to all clients unconditionally.
spring.cloud.config.override-none
- You can change the priority of all overrides in the client to be more like default values, letting applications supply their own values in environment variables or System properties, by setting the spring.cloud.config.override-none=true flag (the default is false) in the remote repository.
spring.cloud.config.allow-override
- If you enable config first bootstrap, you can allow client applications to override configuration from the config server by placing two properties within the applications configuration coming from the config server.
spring.cloud.config.server.health.
- You can configure the Health Indicator to check more applications along with custom profiles and custom labels
spring.cloud.config.server.accept-empty
- You can set
spring.cloud.config.server.accept-empty
tofalse
so that the server returns an HTTP404
status, if the application is not found. By default, this flag is set totrue
.
- You can set
Encryption and decryption (symmetric)
- encrypt.key
- It is convenient to use a symmetric key since it is a single property value to configure.
- spring.cloud.config.server.encrypt.enabled
- You can set this to
false
, to disable server-side decryption.
- You can set this to
- encrypt.key
Refresh
Services that consume properties need to know about the change before it happens. The default notification method for Config Server for Spring involves manually triggering the refresh event, such as refresh by call https://<YOUR_CONFIG_CLIENT_HOST_NAME>/actuator/refresh
, which may not be feasible if there are many app instances.
Instead, you can automatically refresh values from Config Server by letting the config client poll for changes based on a refresh internal. Use the following steps to automatically refresh values from Config Server.
Register a scheduled task to refresh the context in a given interval, as shown in the following example.
@Configuration @AutoConfigureAfter({RefreshAutoConfiguration.class, RefreshEndpointAutoConfiguration.class}) @EnableScheduling public class ConfigClientAutoRefreshConfiguration implements SchedulingConfigurer { @Value("${spring.cloud.config.refresh-interval:60}") private long refreshInterval; @Value("${spring.cloud.config.auto-refresh:false}") private boolean autoRefresh; private final RefreshEndpoint refreshEndpoint; public ConfigClientAutoRefreshConfiguration(RefreshEndpoint refreshEndpoint) { this.refreshEndpoint = refreshEndpoint; } @Override public void configureTasks(ScheduledTaskRegistrar scheduledTaskRegistrar) { if (autoRefresh) { // set minimal refresh interval to 5 seconds refreshInterval = Math.max(refreshInterval, 5); scheduledTaskRegistrar.addFixedRateTask(refreshEndpoint::refresh, Duration.ofSeconds(refreshInterval)); } } }
Enable
autorefresh
and set the appropriate refresh interval in the application.yml file. In the following example, the client polls for a configuration change every 60 seconds, which is the minimum value you can set for a refresh interval.By default,
autorefresh
is set tofalse
, andrefresh-interval
is set to 60 seconds.spring: cloud: config: auto-refresh: true refresh-interval: 60 management: endpoints: web: exposure: include: - refresh
Add
@RefreshScope
in your code. In the following example, the variableconnectTimeout
is automatically refreshed every 60 seconds.@RestController @RefreshScope public class HelloController { @Value("${timeout:4000}") private String connectTimeout; }
Encryption and decryption with a symmetric key
Server-side decryption
By default, server-side encryption is enabled. Use the following steps to enable decryption in your application.
Add the encrypted property in your .properties file in your git repository.
For example, your file should resemble the following example:
message={cipher}f43e3df3862ab196a4b367624a7d9b581e1c543610da353fbdd2477d60fb282f
Update the Config Server for Spring Java component to use the git repository that has the encrypted property and set the encryption key.
Before you run the following command, replace placeholders surrounded by
<>
with your values.az containerapp env java-component config-server-for-spring update \ --environment <ENVIRONMENT_NAME> \ --resource-group <RESOURCE_GROUP> \ --name <JAVA_COMPONENT_NAME> \ --configuration spring.cloud.config.server.git.uri=<URI> encrypt.key=randomKey
Client-side decryption
You can use client side decryption of properties by following the steps:
Add the encrypted property in your
*.properties*
file in your git repository.Update the Config Server for Spring Java component to use the git repository that has the encrypted property and disable server-side decryption.
Before you run the following command, replace placeholders surrounded by
<>
with your values.az containerapp env java-component config-server-for-spring update \ --environment <ENVIRONMENT_NAME> \ --resource-group <RESOURCE_GROUP> \ --name <JAVA_COMPONENT_NAME> \ --configuration spring.cloud.config.server.git.uri=<URI> spring.cloud.config.server.encrypt.enabled=false
In your client app, add the decryption key
ENCRYPT_KEY=randomKey
as an environment variable.Alternatively, if you include spring-cloud-starter-bootstrap on the
classpath
, or setspring.cloud.bootstrap.enabled=true
as a system property, setencrypt.key
inbootstrap.properties
.Before you run the following command, replace placeholders surrounded by
<>
with your values.az containerapp update \ --name <APP_NAME> \ --resource-group <RESOURCE_GROUP> \ --set-env-vars "ENCRYPT_KEY=randomKey"
encrypt: key: somerandomkey