confd Maven Plugin

Examples

Basic usage: prepare + generate in a single step

Let’s say that you have 2 files to generate, file01.properties and datasource.xml, in the target/generated-configuration directory, you can use the following configuration.

By convention, maven-confd-plugin templates and dictionaries are located in src/main/confd/templates and src/main/confd/dictionaries

<build>
    <plugins>
        <plugin>
            <groupId>com.github.nodevops</groupId>
            <artifactId>confd-maven-plugin</artifactId>
            <version>0.1.0-SNAPSHOT</version>
            <executions>
                <execution>
                    <id>prepare</id>
                    <goals>
                        <goal>prepare</goal>
                    </goals>
                    <configuration>
                    <templates>
                        <template>
                            <src>src/main/confd/templates/template01.tmpl</src>
                            <dest>target/generated-configuration/file01.properties</dest>
                            <keys>
                                <value>/web</value>
                            </keys>
                        </template>
                        <template>
                            <src>src/main/confd/templates/template02.tmpl</src>
                            <dest>target/generated-configuration/datasource.xml.tmpl</dest>
                            <keys>
                                <value>/web</value>
                            </keys>
                        </template>
                    </templates>
                    </configuration>
                </execution>
                <execution>
                    <id>generate</id>
                    <goals>
                        <goal>process</goal>
                    </goals>
                    <configuration>
                        <processor>
                            <name>local-confd-processor</name>
                            <properties>
                                <property>
                                    <name>binary.path</name>
                                    <value>/usr/local/bin/confd</value>
                                </property>
                            </properties>
                        </processor>
                        <dictionary>src/main/confd/dictionaries/env01.dict</dictionary>
                    </configuration>
                </execution>
            </executions>
        </plugin>
    </plugins>
</build>

This example does not really match a real case usage though, because you usally don’t deploy on your local dev environment, do you?

Typical use case : local development + delivery package

A full example of this setup can be found in the spring-boot sample in our sample usages project.

Local Development

We want to be able to generate our config file for the local dev environment, and use it, so:

we rely on the common/shared configuration (i.e. not associated to a specific profile) that calls the prepare goal of the plugin. The prepare goal will generate a confd toml configuration file that would target a final generated file in the target/generated-configuration directory
we activate a run-local profile that triggers the generate goal that will process the template according to our local dictionary stored in src/main/confd/dictionary/local.dict
because we want the build to be independent of the dev environment, we use the java-processor that doesn’t rely on the confd binary
the run-local profile also specifies to springboot where it can find its config file (through the springboot plugin)

Get ready for the delivery

We want to generate a configuration artifact that will carry the templates and the ready to use confd toml files

we rely on the common/shared configuration, that only calls the prepare goal
we use a dedicated delivery profile that overrides the final destination of the target file (that will be stored in the toml config file)
the same delivery profile uses the assembly plugin to generate a zip file that can be unzipped as-is in the /etc/confd directory on the destination server(s). This is the default directory structure expected by the confd binary

pom.xml extract

...
<build>
    <plugins>
    ...
    <plugin>
        <groupId>com.github.nodevops</groupId>
        <artifactId>confd-maven-plugin</artifactId>
        <executions>
            <execution>
                <!-- common step shared by all profiles that prepare the config file for further usage /-->
                <id>prepare</id>
                <goals>
                    <goal>prepare</goal>
                </goals>
                <configuration>
                    <forceDestToLocalFileSystemType>true</forceDestToLocalFileSystemType>
                    <templates>
                        <template>
                            <id>application.yml</id>
                            <src>src/main/confd/templates/application.yml.tmpl</src>
                            <dest>${project.basedir}/target/generated-configuration/application.yml</dest>
                            <keys>
                                <value>/your/namespace</value>
                                <value>/runtime</value>
                            </keys>
                        </template>
                    </templates>
                </configuration>
            </execution>
        </executions>
    </plugin>
    ...
    </plugins>
</build>
...
<profiles>
    <profile>
        <id>run-local</id>
        <activation>
            <activeByDefault>true</activeByDefault>
        </activation>
        <build>
            <plugins>
                <plugin>
                    <groupId>com.github.nodevops</groupId>
                    <artifactId>confd-maven-plugin</artifactId>
                    <executions>
                        <execution>
                            <!-- we want to generate the config files because we need it to run now /-->
                            <id>generate</id>
                            <goals>
                                <goal>process</goal>
                            </goals>
                            <configuration>
                                <processor>
                                    <name>java-processor</name>
                                </processor>
                                <dictionary>src/main/confd/dictionaries/local.dict</dictionary>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>
                <plugin>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-maven-plugin</artifactId>
                    <configuration>
                        <arguments>
                            <argument>--spring.config.location=file:target/generated-configuration/application.yml
                            </argument>
                        </arguments>
                    </configuration>
                </plugin>
            </plugins>
        </build>
    </profile>
    <profile>
        <id>delivery</id>
        <build>
            <plugins>
                <plugin>
                    <groupId>com.github.nodevops</groupId>
                    <artifactId>confd-maven-plugin</artifactId>
                    <executions>
                        <execution>
                            <!-- mandatory: use the same id to get the benefit of the merge of the values with the global configuration -->
                            <id>prepare</id>
                            <goals>
                                <goal>prepare</goal>
                            </goals>
                            <configuration>
                                <forceDestToLocalFileSystemType>false</forceDestToLocalFileSystemType>
                                <templates>
                                    <template>
                                        <id>application.yml</id>
                                        <!-- we only need to override the dest value, as long as we keep the templates in the same order as in the global config -->
                                        <dest>/usr/local/appli/config/application.yml</dest>
                                    </template>
                                </templates>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>
                <plugin>
                    <groupId>org.apache.maven.plugins</groupId>
                    <artifactId>maven-assembly-plugin</artifactId>
                    <executions>
                        <execution>
                            <id>confd</id>
                            <goals>
                                <goal>single</goal>
                            </goals>
                            <phase>package</phase>
                            <configuration>
                                <descriptors>
                                    <descriptor>src/main/assembly/confd.xml</descriptor>
                                </descriptors>
                            </configuration>
                        </execution>
                    </executions>
                </plugin>
            </plugins>
        </build>
    </profile>
</profiles>