Apollo is a reliable configuration management system suitable for microservice configuration management scenarios.
Apollo - A reliable configuration management system
Apollo is a reliable configuration management system. It can centrally manage the configurations of different applications and different clusters. It is suitable for microservice configuration management scenarios.
The server side is developed based on Spring Boot and Spring Cloud, which can simply run without the need to install additional application containers such as Tomcat.
The Java SDK does not rely on any framework and can run in all Java runtime environments. It also has good support for Spring/Spring Boot environments.
The .Net SDK does not rely on any framework and can run in all .Net runtime environments.
Unified management of the configurations of different environments and different clusters
Apollo provides a unified interface to centrally manage the configurations of different environments, different clusters, and different namespaces
The same codebase could have different configurations when deployed in different clusters
With the namespace concept, it is easy to support multiple applications to share the same configurations, while also allowing them to customize the configurations
Multiple languages is provided in user interface(currently Chinese and English)
Configuration changes takes effect in real time (hot release)
After the user modified the configuration and released it in Apollo, the sdk will receive the latest configurations in real time (1 second) and notify the application
Release version management
Every configuration releases are versioned, which is friendly to support configuration rollback
Grayscale release
Support grayscale configuration release, for example, after clicking release, it will only take effect for some application instances. After a period of observation, we could push the configurations to all application instances if there is no problem
Authorization management, release approval and operation audit
Great authorization mechanism is designed for applications and configurations management, and the management of configurations is divided into two operations: editing and publishing, therefore greatly reducing human errors
All operations have audit logs for easy tracking of problems
Client side configuration information monitoring
It's very easy to see which instances are using the configurations and what versions they are using
Rich SDKs available
Provides native sdks of Java and .Net to facilitate application integration
Support Spring Placeholder, Annotation and Spring Boot ConfigurationProperties for easy application use (requires Spring 3.1.1+)
Http APIs are provided, so non-Java and .Net applications can integrate conveniently
Rich third party sdks are also available, e.g. Golang, Python, NodeJS, PHP, C, etc
Open platform API
Apollo itself provides a unified configuration management interface, which supports features such as multi-environment, multi-data center configuration management, permissions, and process governance
However, for the sake of versatility, Apollo will not put too many restrictions on the modification of the configuration, as long as it conforms to the basic format, it can be saved.
In our research, we found that for some users, their configurations may have more complicated formats, such as xml, json, and the format needs to be verified
There are also some users such as DAL, which not only have a specific format, but also need to verify the entered value before saving, such as checking whether the database, username and password match
For this type of application, Apollo allows the application to modify and release configurations through open APIs, which has great authorization and permission control mechanism built in
Simple deployment
As an infrastructure service, the configuration center has very high availability requirements, which forces Apollo to rely on external dependencies as little as possible
Currently, the only external dependency is MySQL, so the deployment is very simple. Apollo can run as long as Java and MySQL are installed
Apollo also provides a packaging script, which can generate all required installation packages with just one click, and supports customization of runtime parameters