What is the difference between putting a property on application yml or bootstrap yml in spring boot

Question

What is the difference between putting a property on application yml or bootstrap yml in spring boot  In logging config case  the application works different

User · Answer

bootstrap yml or bootstrap properties  It s only used needed if you re using Spring Cloud and your application s configuration is stored on a remote configuration server  e g  Spring Cloud Config Server    From the documentation      A Spring Cloud application operates by creating a  bootstrap  context  which is a parent context for the main application  Out of the box it is responsible for loading configuration properties from the external sources  and also decrypting properties in the local external configuration files     Note that the bootstrap yml or bootstrap properties can contain additional configuration  e g  defaults  but generally you only need to put bootstrap config here   Typically it contains two properties    location of the configuration server  spring cloud config uri  name of the application  spring application name    Upon startup  Spring Cloud makes an HTTP call to the config server with the name of the application and retrieves back that application s configuration   application yml or application properties  Contains standard application configuration - typically default configuration since any configuration retrieved during the bootstrap process will override configuration defined here

User · Answer

Just my 2 Cents here     Bootstrap yml or Bootstrap properties is used to fetch the config from Spring Cloud Server   For Example  in My Bootstrap properties file I have the following Config  spring application name Calculation-service spring cloud config uri http   localhost 8888   On starting the application   It tries to fetch the configuration for the service by connecting to http   localhost 8888 and looks at Calculation-service properties present in Spring Cloud Config server  You can validate the same from logs of Calcuation-Service when you start it up  INFO 10988 ---    restartedMain  c c c ConfigServicePropertySourceLocator   Fetching config from server at   http   localhost 8888

User · Answer

Bootstrap yml is the first file loaded when you start spring boot application and application property is loaded when application starts  So  you keep  may be your config server s credentials etc   in bootstrap yml which is required during loading application and then in application properties you keep may be database URL etc

User · Answer

Well  I totally agree with answers already exist on this point    bootstrap yml is used to save parameters that point out where the remote configuration is and Bootstrap Application Context is created with these remote configuration    Actually  it is also able to store normal properties just the same as what application yml do  But pay attention on this tricky thing    If you do place properties in bootstrap yml  they will get lower precedence than almost any other property sources  including application yml  As described here    Let s make it clear  there are two kinds of properties related to bootstrap yml     Properties that are loaded during the bootstrap phase  We use bootstrap yml to find the properties holder  A file system  git repository or something else   and the properties we get in this way are with high precedence  so they cannot be overridden by local configuration  As described here  Properties that are in the bootstrap yml  As explained early  they will get lower precedence  Use them to set defaults maybe a good idea    So the differences between putting a property on application yml or bootstrap yml in spring boot are     Properties for loading configuration files in bootstrap phase can only be placed in bootstrap yml  As for all other kinds of properties  place them in application yml will get higher precedence

User · Answer

I have just asked the Spring Cloud guys and thought I should share the info I have here   bootstrap yml is loaded before application yml   It is typically used for the following    when using Spring Cloud Config Server  you should specify spring application name and spring cloud config server git uri inside bootstrap yml some encryption decryption information   Technically  bootstrap yml is loaded by a parent Spring ApplicationContext  That parent ApplicationContext is loaded before the one that uses application yml

User · Answer

This answer has been very beautifully explained in book  Microservices Interview Questions  For Java Developers  Spring Boot  Spring Cloud  Cloud Native Applications  by Munish Chandel  Version 1 30  25 03 2018       The following content has been taken from this book  and total credit   for this answer goes to the Author of the book i e  Munish   Chandel   application yml  application yml application properties file is specific to Spring Boot applications  Unless you change the location of external properties of an application  spring boot will always load application yml from the following location    src main resources application yml   You can store all the external properties for your application in this file  Common properties that are available in any Spring Boot project can be found at  https   docs spring io spring-boot docs current reference html common-application-properties html You can customize these properties as per your application needs  Sample file is shown below   spring      application          name  foobar     datasource          driverClassName  com mysql jdbc Driver         url  jdbc mysql   localhost test server      port  9000   bootstrap yml  bootstrap yml on the other hand is specific to spring-cloud-config and is loaded before the application yml  bootstrap yml is only needed if you are using Spring Cloud and your microservice configuration is stored on a remote Spring Cloud Config Server   Important points about bootstrap yml   When used with Spring Cloud Config server  you shall specify the application-name and config git location using below properties      spring application name   application-name  spring cloud config server git uri   git-uri-config      When used with microservices  other than cloud config server   we need to specify the application name and location of config server using below properties     spring application name   spring cloud config uri     This properties file can contain other configuration relevant to Spring Cloud environment for e g  eureka server location  encryption decryption related properties    Upon startup  Spring Cloud makes an HTTP S  call to the Spring Cloud Config Server with the name of the application and retrieves back that application   s configuration   application yml contains the default configuration for the microservice and any configuration retrieved  from cloud config server  during the bootstrap process will override configuration defined in application yml

User · Answer

Bootstrap yml is used to fetch config from the server  It can be for a Spring cloud application or for others  Typically it looks like   spring    application      name   app-name    cloud      config        uri    config server http   some-server-where-config-resides    When we start the application it tries to connect to the given server and read the configuration based on spring profile mentioned in run debug configuration    If the server is unreachable application might even be unable to proceed further  However  if configurations matching the profile are present locally the server configs get overridden   Good approach   Maintain a separate profile for local and run the app using different profiles

User · Answer

Another use for bootstrap yml is to load configuration from kubernetes configmap and secret resources  The application must import the spring-cloud-starter-kubernetes dependency   As with the Spring Cloud Config  this has to take place during the bootstrap phrase    From the docs    spring    application      name  cloud-k8s-app   cloud      kubernetes        config          name  default-name         namespace  default-namespace         sources             Spring Cloud Kubernetes looks up a ConfigMap named c1 in namespace default-namespace          - name  c1   So properties stored in the configmap resource with meta name default-name can be referenced just the same as properties in application yml  And the same process applies to secrets    spring    application      name  cloud-k8s-app   cloud      kubernetes        secrets          name  default-name         namespace  default-namespace         sources             Spring Cloud Kubernetes looks up a Secret named s1 in namespace default-namespace          - name  s1

[java] What is the difference between putting a property on application.yml or bootstrap.yml in spring boot?

`bootstrap.yml` or `bootstrap.properties`

`application.yml` or `application.properties`

Examples related to java

Examples related to spring

Examples related to spring-boot

Examples related to spring-cloud