maven - How to add dependency JAR in java azure functions

Question

Is there a way to add third party jars to Azure functions using JAVA. I would need to have the json-simple jar and jackson-databind jars to be available for the function at run time. Right now, My code throws a runtime exception(ClassNotFound Exception) as the function is not able to reference the jar during runtime because it is unavailable.

I tried using maven-shade-plugin. It does create an executable jar including the external jars but the deployment still takes the original jar.

Please suggest.

Thanks.

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>com.sce.api.learning</groupId>
    <artifactId>myApi</artifactId>
    <version>1.0-SNAPSHOT</version>
    <packaging>jar</packaging>

    <name>Azure Java Functions</name>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <maven.compiler.source>1.8</maven.compiler.source>
        <maven.compiler.target>1.8</maven.compiler.target>
        <functionAppName>mckapi-http-nov2</functionAppName>
    </properties>

    <dependencies>
        <dependency>
            <groupId>com.microsoft.azure</groupId>
            <artifactId>azure-functions-java-core</artifactId>
            <version>1.0.0-beta-1</version>
        </dependency>

        <!-- Adding GSON dependancy -->
        <dependency>
    <groupId>com.google.code.gson</groupId>
    <artifactId>gson</artifactId>
    <version>1.4</version>
</dependency>

<dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.6.3</version>
</dependency>

<dependency>
    <groupId>com.googlecode.json-simple</groupId>
    <artifactId>json-simple</artifactId>
    <version>1.1.1</version>
</dependency>
<dependency>
    <groupId>org.json</groupId>
    <artifactId>json</artifactId>
    <version>20171018</version>
</dependency>

        <!-- Test -->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <pluginManagement>
            <plugins>
                <plugin>
                    <artifactId>maven-resources-plugin</artifactId>
                    <version>3.0.2</version>
                </plugin>
                <plugin>
                    <groupId>com.microsoft.azure</groupId>
                    <artifactId>azure-functions-maven-plugin</artifactId>
                    <version>0.1.4</version>
                </plugin>
            </plugins>
        </pluginManagement>

        <plugins>
            <plugin>
                <groupId>com.microsoft.azure</groupId>
                <artifactId>azure-functions-maven-plugin</artifactId>
                <configuration>
                    <resourceGroup>java-functions-group</resourceGroup>
                    <appName>${functionAppName}</appName>
                    <region>westus2</region>
                    <appSettings>
                        <property>
                            <name>FUNCTIONS_EXTENSION_VERSION</name>
                            <value>beta</value>
                        </property>
                    </appSettings>
                </configuration>
                <executions>
                    <execution>
                        <id>package-functions</id>
                        <goals>
                            <goal>package</goal>
                        </goals>
                    </execution>
                </executions>
            </plugin>
            <plugin>
                <artifactId>maven-resources-plugin</artifactId>
                <executions>
                    <execution>
                        <id>copy-resources</id>
                        <phase>package</phase>
                        <goals>
                            <goal>copy-resources</goal>
                        </goals>
                        <configuration>
                            <overwrite>true</overwrite>
                            <outputDirectory>${project.build.directory}/azure-functions/${functionAppName}
                            </outputDirectory>
                            <resources>
                                <resource>
                                    <directory>${project.basedir}</directory>
                                    <includes>
                                        <include>host.json</include>
                                        <include>local.settings.json</include>
                                        **<include>**/*.jar</include>**<!-- This includes the jar files in the target/lib folder -->
                                    </includes>
                                </resource>
                            </resources>
                        </configuration>
                    </execution>
                </executions>
            </plugin>

            <plugin>
                <groupId>org.apache.maven.plugins</groupId>
                <artifactId>maven-shade-plugin</artifactId>
                <executions>
                    <execution>
                        <phase>package</phase>
                        <goals>
                            <goal>shade</goal>
                        </goals>
                        <configuration>
                        <overwrite>true</overwrite>
                            <outputDirectory>${project.build.directory}/azure-functions/${functionAppName}
                            </outputDirectory>
              <shadedArtifactAttached>false</shadedArtifactAttached>
            </configuration>
                    </execution>
                </executions>
                <configuration>
                    <finalName>${artifactId}-${version}</finalName>
                </configuration>
            </plugin>

        </plugins>

    </build>

</project>

Answer 1

I had the same problem and I figured out how to arrange a solution.

First of all, start from a brand new Maven project following the straightforward guide at this link.

Assume <project_root_path> as the folder where you will create the project.

Once you have generated your maven project, just add this maven-assembly-plugin plugin on your <project_root_path>/pom.xml within <build><plugins>...</plugins></build>:

<plugin>
   <artifactId>maven-assembly-plugin</artifactId>
   <configuration>
      <outputDirectory>${project.build.directory}/azure-functions/${functionAppName}</outputDirectory>
      <appendAssemblyId>false</appendAssemblyId>
      <descriptorRefs>
         <descriptorRef>jar-with-dependencies</descriptorRef>
      </descriptorRefs>
      <archive />
   </configuration>
   <executions>
      <execution>
         <id>make-assembly</id>
         <phase>package</phase>
         <goals>
            <goal>assembly</goal>
         </goals>
      </execution>
   </executions>
</plugin>

Compiling and packaging the Azure Function with command mvn clean compile package will produce a jar on path <project_root_path>/target/<project_name>.jar containing all the external libraries listed under the <dependencies></dependencies> of the pom.xml.

Note 1: if you didn't modify the standard pom.xml, <project_name> will be generated according to <artifactId>_<version>.jar.

Note 2: if you don't use the <appendAssemblyId>false</appendAssemblyId> directive on the above snippet, the <project_name> will be <artifactId>_<version>-<descriptorRef>.jar. Consider this for the following instructions.

So, now you should have your complete <project_root_path>/target/<project_name>.jar, but before using it you have to copy it under <project_root_path>/target/azure-functions/<azure_function_name>/ where <azure_function_name> is the name you gave to your function during the creation progress documented on the above link.

Now you can test it using the Azure Maven plugins:

1. Running the Azure Function on your machine locally: mvn azure-functions:run
2. Deploying the Azure Function on your subscription: mvn azure-functions:deploy

At the end, the key point is moving the jar generated with maven-assembly-plugin into the right place where the Azure Maven plugin will look during the run/deploy process. I wish I could find a more automatic way using standard Maven commands.

Hope this helps.

Ciao IP

Edit (17/11/17)

Adding <outputDirectory>${project.build.directory}/azure-functions/${functionAppName}</outputDirectory> within the <configuration> POM tag and changing <goal> tag to assembly, it makes Maven to automatically copy the final JAR in the Azure Function staging directory. This allows the mvn azure-functions:run and mvn azure-functions:deploy commands to directly use the correct JAR file containing all dependency. No manual actions are requested anymore.

The above POM have been updated accordingly.

Edit (21/11/17)

In case you want to use the Maven Shade Plugin instead of the Maven Assembly Plugin, replace the above XML snippet with this one:

<plugin>
   <groupId>org.apache.maven.plugins</groupId>
   <artifactId>maven-shade-plugin</artifactId>
   <version>3.1.0</version>
   <configuration>
      <shadedArtifactAttached>false</shadedArtifactAttached>
      <outputFile>${project.build.directory}/azure-functions/${functionAppName}/${project.artifactId}-${project.version}.jar</outputFile>
      <filters>
         <filter>
            <artifact>*:*</artifact>
            <excludes>
               <exclude>META-INF/*.SF</exclude>
               <exclude>META-INF/*.DSA</exclude>
               <exclude>META-INF/*.RSA</exclude>
            </excludes>
         </filter>
      </filters>
   </configuration>
   <executions>
      <execution>
         <phase>package</phase>
         <goals>
            <goal>shade</goal>
         </goals>
      </execution>
   </executions>
</plugin>

It will work using the same standard Maven commands mentioned before.