Liquibase failed to start because no changelog could be found at ‘classpath:/db/changelog/db.changelog-master.yaml’.

The error message “liquibase failed to start because no changelog could be found at ‘classpath:/db/changelog/db.changelog-master.yaml'” occurs when Liquibase is unable to locate the specified changelog file.

Liquibase is a database schema migration tool that requires a changelog file to track and manage changes to your database schema over time. The changelog file specifies the changes to be applied to the database and their order of execution.

Reasons for the error:

1. The specified changelog file path is incorrect.
2. The changelog file is not present in the specified location.
3. The classpath resource is not accessible or misconfigured.

Solution:

Here are a few steps you can take to resolve the issue:

1. Double-check the path of the changelog file specified in the Liquibase configuration. Make sure it matches the actual location.
2. Verify that the specified changelog file exists in the specified location. Correct any typos in the file name or directory structure if necessary.
3. Check the classpath configuration and ensure that it includes the location of the changelog file. In most cases, the classpath should be set to include the source folder where the changelog file resides.

Example:

Let’s say your project structure is as follows:

  project
  ├── src
  │   ├── main/java
  │   └── resources
  │       └── db
  │           └── changelog
  │               └── db.changelog-master.yaml
  └── pom.xml
  

In this case, to correctly specify the changelog file path in Liquibase configuration, you should use ‘classpath:/db/changelog/db.changelog-master.yaml’, assuming you are configuring Liquibase programmatically or through a configuration file like ‘liquibase.properties’.