Migrate Spring Cloud Config Server from Azure Spring Apps to Azure Container Apps

Note

The Basic, Standard, and Enterprise plans will be deprecated starting from mid-March, 2025, with a 3 year retirement period. We recommend transitioning to Azure Container Apps. For more information, see the Azure Spring Apps retirement announcement.

The Standard consumption and dedicated plan will be deprecated starting September 30, 2024, with a complete shutdown after six months. We recommend transitioning to Azure Container Apps. For more information, see Migrate Azure Spring Apps Standard consumption and dedicated plan to Azure Container Apps.

This article applies to: ✅ Basic/Standard ✅ Enterprise

This article describes how to migrate Spring Cloud Config Server to Config Server for Spring in Azure Container Apps. Azure Container Apps manages Config Server for Spring, which has similar functions as Spring Cloud Config Server in Azure Spring Apps.

Prerequisites

• An Azure Spring Apps instance with Configure Server enabled.
• An Azure Container Apps Environment for Config Server and an Azure Container Apps instance.

Provision Config Server

Azure portal

The following steps show you how to provision a Config Server for Spring in your Azure Container Apps:

1. Navigate to your Azure Container Apps environment in the Azure portal.

2. In the menu, select Services > Services.

3. Open the Configure drop-down list, and then select Java component.

4. In the Configure Java component panel, enter the following values:

   Property	Value
   Java component type	Select Config Server for Spring.
   Java component name	Enter configserver.

5. In the Git repositories section, select Add, and then migrate the values from Application Configuration Service to here, as shown in the following table. Choose one repository as the default repository of Config Server for Spring.

   Property	Value
   Type	Select DEFAULT.
   URI	Enter the value of URI of the repository.
   Branch name	Enter the value of label of the repository.
   Search paths	Enter the value of search path of the repository.
   Authentication	Select the authentication type of the repository and enter the corresponding information.

   Leave the rest of the fields with the default values and then select Add.

6. If you have multiple repositories, select Add to migrate other repositories. For Type, select Other, and then migrate other properties as shown in the previous step and the following table:

   Property	Value
   Type	Select DEFAULT.
   Pattern	Enter the Patterns value for the repository in the {application} or {application}/{profile} format.

7. In the Binding section, open the dropdown to select the apps to bind to the Config Server for Spring.

8. Select Next.

9. To set up Config Server, on the Review tab, select Configure, and then follow the instructions in the configuration section.

After successful creation, you can see that the Provisioning State of Config Server for Spring is Succeeded.

Azure CLI

Use the following command to create and configure the Config Server for Spring Java component:

az containerapp env java-component config-server-for-spring create \
    --resource-group <resource-group-name> \
    --name <config-server-name> \
    --environment <azure-container-app-environment-name> \
    --min-replicas 1 \
    --max-replicas 1 \
    --configuration spring.cloud.config.server.git.uri=<URI> spring.cloud.config.server.git.default-label=<label>

All properties are set using the format --configuration <CONFIGURATION_KEY>=<CONFIGURATION_VALUE>. To map existing configurations to the key-value pairs of the Config Server, see the configuration section.

Resource allocation

The container resource allocation for the managed Config Server in Azure Container Apps is fixed to the following values:

• CPU: 0.5 vCPU
• Memory: 1 Gi

To configure the instance count of Config Server for Spring, you need to update the parameters --min-replicas and --max-replicas with the same value. This configuration ensures that the instance count remains fixed. Currently, the system doesn't support autoscaling configurations for dynamic scaling.

Configure Config Server

Map the default Git repository and additional repositories configured in the Spring Cloud Config Server within Azure Spring Apps to the default and other repositories in the Config Server for Spring deployed in Azure Container Apps. The following table shows the mapping relationships for properties:

Property name in Azure Spring Apps	CONFIGURATION_KEY	CONFIGURATION_VALUE
uri	spring.cloud.config.server.git.uri spring.cloud.config.server.git.repos.{repoName}.uri	The uri of the remote repository.
search path	spring.cloud.config.server.git.search-paths spring.cloud.config.server.git.repos.{repoName}.search-paths	Search paths to use within the local working copy. By default, searches only the root.
label	spring.cloud.config.server.git.default-label spring.cloud.config.server.git.repos.{repoName}.default-label	The label used for Git.
name in additional repositories	{repoName} in the following configurations.
Patterns in additional repositories	spring.cloud.config.server.git.repos.{repoName}.pattern
username	spring.cloud.config.server.git.username spring.cloud.config.server.git.repos.{repoName}.username	Enter the username for authentication with remote repository if the authentication type is HTTP Basic.
password	spring.cloud.config.server.git.password spring.cloud.config.server.git.repos.{repoName}.password	Enter the password for authentication with remote repository if the authentication type is HTTP Basic.
private key	spring.cloud.config.server.git.private-key spring.cloud.config.server.git.repos.{repoName}.private-key	Valid SSH private key if the authentication type is SSH.
host key	spring.cloud.config.server.git.host-key spring.cloud.config.server.git.repos.{repoName}.host-key	Valid SSH host key if the authentication type is SSH. Must be set if host-key-algorithm is also set.
host key algorithm	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 if the authentication type is SSH. Must be set if host-key is also set.

For more Config Server properties, see the Configuration options section of Connect to a managed Config Server for Spring in Azure Container Apps.

Deploy the application to Azure Container Apps

After testing the application locally, you can deploy the new image to the Azure Container Apps application.

Azure portal

Use the following steps to deploy:

1. Navigate to your Azure Container Apps application in the Azure portal.
2. In the menu, select Application > Containers.
3. Select Edit and deploy to open the Create and deploy new revision page.
4. In the Container image section, select the image and then select Edit.
5. In the Edit a container section, on the Properties tab, choose the new image of the application.
6. On the Environment variables tab, for Name, specify spring.application.name. Then, for Source, choose Manual entry and specify the config file name where the application consumes the configuration.
7. Select Save to deploy the new revision.

Azure CLI

Use the following command to update the container app that consumes the configuration data:

az containerapp update \
    --resource-group <your-resource-group> \
    --name <container-app-name> \
    --image <new-container-image> \
    --bind <config-server-name> \
    --set-env-vars spring.application.name=<config-file-name>

The --bind <config-server-name> parameter creates the link between your container app and the configuration component. You should add the environment variable by setting --set-env-vars spring.application.name=<config-file-name> to the app container so that the app can consume the configuration from the right config file.

Troubleshoot

You can view logs for the managed Config Server for Spring in Azure Container Apps using Log Analytics. Use the following steps:

1. Navigate to your Azure Container Apps environment in the Azure portal.

2. Select the Monitoring > Logs menu.

3. To view logs, enter a query into the query editor for the ContainerAppSystemLogs_CL table, as shown in the following example:

   ContainerAppSystemLogs_CL
   | where ComponentType_s == "SpringCloudConfig"
   | project Time=TimeGenerated, ComponentName=ComponentName_s, Message=Log_s
   | take 100
   

For more information about querying logs, see Observability of managed Java components in Azure Container Apps.