Spring Cloud Client Read Multipart config file from config Server

from: https://stackoverflow.com/questions/43956072/how-to-read-multiple-config-file-from-spring-cloud-config-server

一个Client需要从Config Server读取多个配置的解决方案。

通常是 ,虽然也会有些问题(见第二个answer,但主体这样就能应对大多数场景了。但经过测试,很多common的property,是不需要加profile信息的,这样可能并不需要完全对name和profile做排列组合,但这也会使得所有的env用同一份配置),加载顺序为从前到后,后面的覆盖前面的

spring.cloud.config.name=a,b,c
spring.cloud.config.profile=dev,mq,cache

How to read multiple config file from Spring Cloud Config Server

Spring cloud config server supports reading property files with name ${spring.application.name}.properties. However I have 2 properties files in my application.

a.properties
b.properties

Can I get the config server to read both these properties files?

4 Answers

Rename your properties files in git or file system where your config server is looking at.

a.properties -> <your_application_name>.properties
a.properties -> <your_application_name>-<profile-name>.properties

For example, if your application name is test and you are running your application on dev profile, below two properties will be used together.

test.properties
test-dev.properties

Also you can specify additional profiles in bootstrap.properties of your config client to retrieve more properties files like below. For example,

spring:
  profiles: dev
  cloud:
    config:
      uri: http://yourconfigserver.com:8888
      profile: dev,dev-db,dev-mq

If you specify like above, below all files will be used together.

test.properties
test-dev.properties
test-dev-db.prpoerties
test-dev-mq.properties

you can also do spring.application.name=a,b , But Its better to use spring.cloud.config.name instead of spring.application.name, since other libraries/ features might depend on it

  • What if you have multiple services and you want to share same generic property files? (jdbc.properties, server.properties, etc)

Note that the provided answer assumes your property files address different execution profiles. If they dont, i.e., your properties are split into different files for some other reason, e.g., maintenance purposes, divided by business/functional domain, or any other reason that suits your needs, then, by defining a profile for each such file, you are just “abusing” the profile feature, for achieving your goal (multiple property files per app).

You could then ask “OK, so what is the problem with that?”. The problem is that you restrain yourself from various possibilities that you would otherwise have. If you actually want to customize your application configuration by profile you will have to create pseudo, sub, profiles for that since the file name is already a profile. Example:

Your application configuration could be customized by different profiles, which you use inside your springboot application (e.g. in @Profile() annotation), let them be dev, uat, prod. You can boot your application setting different profiles as active, e.g. ‘dev’ vs ‘uat’, and get the group of properties that you desire. For your a.properties b.properties and c.properties file, if different file names were supported, you would have a-dev.properties b-dev.properties and c-dev.properties files vs a-uat.properties b-uat.properties and c-uat.properties files for ‘dev’ and ‘uat’ profile.

Nevertheless, with the provided solution, you already have defined 3 profiles for each file: appname-a.properties appname-b.properties, and appname-c.properties: a, b, and c. Now imagine you have to create a different profile for each… profile(! it already shows something goes wrong here)! you would end up with a lot of profile permutations (which would get worse as files increase): The files would be appname-a-dev.properties, appname-b-dev.properties, app-c-dev.properties vs appname-a-uat.properties, appname-b-uat.properties, app-c-uat.properties, but the profiles would have been increased from [‘dev’, ‘ uat’] to [‘a-dev’, ‘b-dev’, ‘c-dev’, ‘a-uat’, ‘b-uat’, ‘c-uat’] !!!

Even worse, how are you going to cope with all these profiles inside your code and more specifically your @Profile() annotations? Will you clutter the code space with “artificial” profiles just because you want to add one or two more different property files? It should have been sufficient to define your dev or uat profiles, where applicable, and define somewhere else the applicable property file names (which could then be further supported by profile, without any other configuration action), just as it happens in the externalized properties configuration for individual springboot apps

For argument completeness, I will just add here that if you want to switch to .yml property files one day, with the provided profile-based naming solution, you also loose the ability to define different “yaml document sections per profile” inside the same .yml file (Yes, in .yml you can have one property file yet define multiple logical yml documents inside, which its usually done for customizing the properties for different profiles, while having all related properties in one place). You loose the ability because you have already used the profile in the file name (appname-profile.yml)

I have issued a pull request with a minor fix for spring-cloud-config-server 1.4.x, which allows defining additionally supported file names (appart from “application[-profile]” and “{appname}[-profile]”, that are currently supported) by providing a spring.cloud.congif.server.searchNames environment property – analogous to spring.config.name for springboot apps. I hope it gets reviewed and accepted.

  • Very pertinent comment. An example of situation that asks for multiple property files (rather than abusing the profile mechanism) would be: you’re using CQRS for Customer. There’s the CustomerCommand app that reads customer-command-xxx.properties, where xxx represents the active profile or profiles. There’s the CustomerQuery app that reads customer-query-xxx.properties. In addition, you want them both to read customer-common-xxx.properties with the properties they share, such as database and message broker connection parameters.

I came across the same requirement lately with a little more constraint that I am not allowed to play around the environment profiles. So I wasn’t allowed to do as the accepted answer. I’m sharing how I did it as an alternative to those who might have same case as me.

In my application, I have properties such as:

appxyz-data-soures.properties
appxyz-data-soures-staging.properties
appxyz-data-soures-production.properties
appxyz-interfaces.properties
appxyz-interfaces-staging.properties
appxyz-interfaces-production.properties
appxyz-feature.properties
appxyz-feature-staging.properties
appxyz-feature-production.properties

application.properties // for my use, contains local properties only
bootstrap.properties // for my use, contains management properties only

In my application, I have these particular properties set that allow me to achieve what I needed. But note I have the rest of needed config as well (enable cloud config, actuator refresh, eureka service discovery and so on) – just highlighting these for emphasis:

spring.application.name=appxyz
spring.cloud.config.name=appxyz-data-soures,appxyz-interfaces,appxyz-feature

You can observe that I didn’t want to play around my application name but instead I used it as prefix for my config property files.

In my configuration server I configured in application.yml to capture pattern: 'appxyz-*':

spring:
  cloud:
    config:
      server:
        git:
          uri: <git repo default>
          repos:
            appxyz:
              pattern: 'appxyz-*'
              uri: <another git repo if you have 1 repo per app>
              private-key: ${git.appxyz.pk}
          strict-host-key-checking: false
          ignore-local-ssh-settings: true
          private-key: ${git.default.pk}

In my Git repository I have the following. No application.properties and bootstrap because I didn’t want those to be published and overridden/refreshed externally but you can do if you want.

appxyz-data-soures.properties
appxyz-data-soures-staging.properties
appxyz-data-soures-production.properties
appxyz-interfaces.properties
appxyz-interfaces-staging.properties
appxyz-interfaces-production.properties
appxyz-feature.properties
appxyz-feature-staging.properties
appxyz-feature-production.properties

It will be the pattern matching pattern: 'appxyz-*' that will capture and return the matching files from my git repository. The profile will also apply and fetch the correct property file accordingly. The prioritization of value is also preserved.

Furthermore, if you wish to add more file in your application (say appxyz-circuit-breaker.properties), we only need to do:

  1. Add the name pattern in the spring.cloud.config.name=...,appxyz-circuit-breaker
  2. The add the copies of the file locally and also externally (in the git repo.

No need to add/modify more or restart your configuration server later on. For new application, it’s like a one time registration thing to add an entry under the repos of application.yml.

Hope it helps in one way or another!

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