Load values from external file into pom.xml - postgresql

Question

I am trying to read some parameters in a pom.xml from an external file. I am using properties-maven-plugin, but I don't really mind any other solution to read values from an external file as a variable in pom.
Here is my plugin:
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>properties-maven-plugin</artifactId>
<version>1.0.0</version>
<executions>
<execution>
<goals>
<goal>read-project-properties</goal>
</goals>
<phase>initialize</phase>
<configuration>
<!--<files>
<file>${apps.basedir}/apps/flywayvariables.properties</file>
<file>/home/gokul/git/sampleproject/apps/flywayvariables.properties</file>
</files>-->
<urls>
<url>file:///${apps.basedir}/apps/flywayvariables.properties</url>
</urls>
</configuration>
</execution>
</executions>
</plugin>
Here is where I am trying to use it:
<plugin>
<groupId>org.flywaydb</groupId>
<artifactId>flyway-maven-plugin</artifactId>
<version>7.0.1</version>
<configuration>
<sqlMigrationSeparator>__</sqlMigrationSeparator>
<locations>
<location>filesystem:${apps.basedir}/apps/flyway</location>
</locations>
<url>jdbc:postgresql://localhost:9000/postgres</url>
<user>${dbuser}</user>
<flyway.user>${dbuser}</flyway.user>
<flyway.password>${dbpassword}</flyway.password>
<password>${dbpassword}</password>
</configuration>
<dependencies>
<dependency>
<groupId>org.postgresql</groupId>
<artifactId>postgresql</artifactId>
<version>42.2.16</version>
</dependency>
</dependencies>
<executions>
<execution>
<id>migrate</id>
<goals>
<goal>migrate</goal>
</goals>
<phase>initialize</phase>
</execution>
</executions>
</plugin>
And here is my properties file:
<properties>
<dbuser>postgres</dbuser>
<dbpassword>test1234</dbpassword>
</properties>
When I run mvn -X initialize, I get the following error:
[DEBUG] Configuring mojo org.codehaus.mojo:properties-maven-plugin:1.0.0:read-project-properties from plugin realm ClassRealm[plugin>org.codehaus.mojo:properties-maven-plugin:1.0.0, parent: sun.misc.Launcher$AppClassLoader#5c647e05]
[DEBUG] Configuring mojo 'org.codehaus.mojo:properties-maven-plugin:1.0.0:read-project-properties' with basic configurator -->
[DEBUG] (f) project = MavenProject: com.example.company:sampleapplication # /home/gokul/git/sampleproject/apps/pom.xml
[DEBUG] (f) quiet = false
[DEBUG] (s) urls = [file:////home/gokul/git/sampleproject/apps/flywayvariables.properties]
[DEBUG] -- end configuration --
[DEBUG] Loading properties from URL file:////home/gokul/git/sampleproject/apps/flywayvariables.properties
[INFO]
[INFO] --- flyway-maven-plugin:7.0.1:migrate (migrate) # apps ---
...
...
...
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 5.422 s (Wall Clock)
[INFO] Finished at: 2020-10-13T01:18:40+02:00
[INFO] Final Memory: 33M/1237M
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.flywaydb:flyway-maven-plugin:7.0.1:migrate (migrate) on project apps: org.flywaydb.core.internal.exception.FlywaySqlException:
[ERROR] Unable to obtain connection from database (jdbc:postgresql://localhost:9000/postgres) for user 'null': The server requested password-based authentication, but no password was provided.
[ERROR] ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
[ERROR] SQL State : 08004
[ERROR] Error Code : 0
[ERROR] Message : The server requested password-based authentication, but no password was provided.
I can see that the plugins are executed in the order I would want and yet the property is not loaded. The file path and permissions shouldn't be an issue since I created the properties file with the same user account as I am executing the maven project. No password was provided error changes to authentication failed error when I input the password manually and only keep the $dbuser as a variable. I have tried changing the names of the variables too, in vain. In the properties-maven-plugin configuration, I tried supplying files instead of urls, but it did not make any difference to maven.
Unfortunately none of the solutions in this question helps me.
Tried the following maven goals:
initialize
verify
validate
install
properties:read-project-properties initialize

Answer 1

I am pretty sure you need to write the properties file in the traditional fashion like
dbuser=postgres
dbpassword=test1234

Answer 2

I do not know why the properties plugin does not work, but Flyway itself supports multiple methods for storing these settings outside of the pom. See the Flyway maven documentation for more details.
Below is some snippets from the link:
Configuration Files
Flyway will search for and automatically load the <user-home>/flyway.conf config file if present.
It is also possible to point Flyway at one or more additional config files. This is achieved by supplying the System property flyway.configFiles as follows:
mvn -Dflyway.configFiles=path/to/myAlternativeConfig.conf flyway:migrate
See https://flywaydb.org/documentation/maven/#config-files for more information.
Maven Settings
Alternatively for storing the database user and password, Maven settings.xml files can also be used:
<settings>
<servers>
<server>
<!-- By default Flyway will look for the server with the id 'flyway-db' -->
<!-- This can be customized by configuring the 'serverId' property -->
<id>flyway-db</id>
<username>myUser</username>
<password>mySecretPwd</password>
</server>
</servers>
</settings>