bootstrap.yml not loading for Spring Boot 2

Question

I'm having a similar problem to this thread (which has not been resolved).

I have a Spring Boot 2 App and have a bootstrap.yml file. There is a property "spring.data.cassandra.keyspace-name" which isn't being picked up. I only have a single bootstrap.yml under src/main/resources.

Important note: If I rename bootstrap.yml to application.yml, everything works perfectly.

This looks like a genuine bug. Can somebody confirm is they are facing this issue as well? Or am I doing something wrong?

The contents of the bootstrap.yml is as below:

spring:
    profiles: default 
    # Pretty-print JSON responses
    jackson:
        serialization:
            indent-output: true
    data:
      cassandra:
        contact-points: localhost
        keyspace-name: samplekeyspace

My pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

<groupId>org.sample.org</groupId>
<artifactId>sample-data</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>

<name>cart-data</name>
<description>Demo project for Spring Boot</description>

<parent>
    <groupId>org.springframework.boot</groupId>
    <artifactId>spring-boot-starter-parent</artifactId>
    <version>2.0.5.RELEASE</version>
    <relativePath/> <!-- lookup parent from repository -->
</parent>

<properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
    <java.version>1.10</java.version>
</properties>

<dependencies>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-actuator</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-data-cassandra-reactive</artifactId>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-webflux</artifactId>
    </dependency>

    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-devtools</artifactId>
        <scope>runtime</scope>
    </dependency>
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <optional>true</optional>
    </dependency>
    <dependency>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-test</artifactId>
        <scope>test</scope>
    </dependency>
    <dependency>
        <groupId>io.projectreactor</groupId>
        <artifactId>reactor-test</artifactId>
        <scope>test</scope>
    </dependency>
</dependencies>

<build>
    <plugins>
        <plugin>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-maven-plugin</artifactId>
        </plugin>
    </plugins>
</build>

The error I am getting is:

Caused by: java.lang.IllegalArgumentException: Could not resolve placeholder 'spring.data.cassandra.keyspace-name' in value "${spring.data.cassandra.keyspace-name}"
    at org.springframework.util.PropertyPlaceholderHelper.parseStringValue(PropertyPlaceholderHelper.java:172) ~[spring-core-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.util.PropertyPlaceholderHelper.replacePlaceholders(PropertyPlaceholderHelper.java:124) ~[spring-core-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.core.env.AbstractPropertyResolver.doResolvePlaceholders(AbstractPropertyResolver.java:237) ~[spring-core-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.core.env.AbstractPropertyResolver.resolveRequiredPlaceholders(AbstractPropertyResolver.java:211) ~[spring-core-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.context.support.PropertySourcesPlaceholderConfigurer.lambda$processProperties$0(PropertySourcesPlaceholderConfigurer.java:175) ~[spring-context-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveEmbeddedValue(AbstractBeanFactory.java:839) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1083) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1062) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:583) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:91) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:372) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1341) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:572) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:495) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:317) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:315) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.0.8.RELEASE.jar:5.0.8.RELEASE]

Answer 1

The bootstrap.yml (or .properties) file is only used, if you use any of the Spring Cloud Starter modules. This is used to specify the spring cloud config server location for bootstrapping a minimal application context that will gather the application properties from the config server and then create a child context with these properties to start the real application. If you do not make use of the Spring Cloud config capabilities, the way to go is to use the application.yml or .properties files for your application.