MS Graph (3.0) Java ClientCredentials Error (java.lang.BootstrapMethodError: java.lang.NoClassDefFoundError: reactor/netty/tcp/ProxyProvider$TypeSpec)

Application Type : Java Spring Boot Daemon application using Client Credentials Flow.

I was earlier using microsoft-graph 2.10.0 for fetching data from Microsoft graph. However with the recent microsoft-graph 3.0.0, I wanted to update the project.

Following the upgrade and auth details, i have used the below to get the GraphServiceClient using ClientCredentials azure-identity:

String proxyUrl = "xxxxx";
int proxyPort = 8080;

ProxyOptions proxyOptions = new ProxyOptions(ProxyOptions.Type.HTTP,new InetSocketAddress(proxyUrl, proxyPort));
// proxyOptions.setCredentials(proxyUser, proxyPassword);

final ClientSecretCredential clientSecretCredential = new ClientSecretCredentialBuilder()
.clientId(this.clientId).clientSecret(this.clientSecret).tenantId(this.tenantId)
.httpClient(HttpClient.createDefault(new HttpClientOptions().setProxyOptions(proxyOptions))).build();

final TokenCredentialAuthProvider authProvider = new TokenCredentialAuthProvider(this.scopes, clientSecretCredential);

final GraphServiceClient graphClient = GraphServiceClient.builder().authenticationProvider(authProvider)
                .buildClient();

pom.xml

<dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
        </dependency>       
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-devtools</artifactId>
            <scope>runtime</scope>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-mail</artifactId>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-thymeleaf</artifactId>
        </dependency>

        <!-- exclude logback , add log4j2 -->
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
            <exclusions>
                <exclusion>
                    <groupId>org.springframework.boot</groupId>
                    <artifactId>spring-boot-starter-logging</artifactId>
                </exclusion>
            </exclusions>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-log4j2</artifactId>
        </dependency>

        <!-- Microsoft Graph -->
        <dependency>
            <groupId>com.microsoft.graph</groupId>
            <artifactId>microsoft-graph</artifactId>
            <version>3.0.0</version>
        </dependency>   

        <!-- For SMTP Email -->
        <dependency>
            <groupId>javax.mail</groupId>
            <artifactId>mail</artifactId>
            <version>1.4.7</version>
        </dependency>
        <dependency>
            <groupId>javax.activation</groupId>
            <artifactId>activation</artifactId>
            <version>1.1.1</version>
            <scope>runtime</scope>
        </dependency>

        <!-- SQL -->
        <dependency>
            <groupId>com.microsoft.sqlserver</groupId>
            <artifactId>mssql-jdbc</artifactId>
            <scope>runtime</scope>
        </dependency>
        
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-configuration-processor</artifactId>
            <optional>true</optional>
        </dependency>   
    </dependencies>

Note : Using 2.10.0 i used to pass the Proxy using JVM arguments, however the same did not work using 3.0.0 hence ended up using the proxyOptions following link.

Issue : Receiving the below error while fetching any data, the error is seen while setting the httpClient in the above code.

2021-03-22T16:04:18,295 ERROR [restartedMain] o.s.b.SpringApplication: Application run failed
java.lang.BootstrapMethodError: java.lang.NoClassDefFoundError: reactor/netty/tcp/ProxyProvider$TypeSpec
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.lambda$build$7(NettyAsyncHttpClientBuilder.java:142)
    at reactor.netty.http.client.HttpClient.tcpConfiguration(HttpClient.java:1343)
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.build(NettyAsyncHttpClientBuilder.java:122)
    at com.azure.core.http.netty.NettyAsyncHttpClientProvider.createInstance(NettyAsyncHttpClientProvider.java:32)
    at com.azure.core.implementation.http.HttpClientProviders.createInstance(HttpClientProviders.java:48)
    at com.azure.core.http.HttpClient.createDefault(HttpClient.java:50)
    at com.app.intune.config.GraphClient.getGraphServiceClient(GraphClient.java:48)
    at com.app.intune.util.UserUtil.getUsersWithRegisteredDevicesAndSave(UserUtil.java:140)
    at com.app.intune.IntuneApplication.run(IntuneApplication.java:61)
    at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:804)
    at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:788)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:333)
    at com.app.intune.IntuneApplication.main(IntuneApplication.java:56)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
Caused by: java.lang.NoClassDefFoundError: reactor/netty/tcp/ProxyProvider$TypeSpec
    ... 18 more
Caused by: java.lang.ClassNotFoundException: reactor.netty.tcp.ProxyProvider$TypeSpec
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 18 more

Any help on the above will be greatly appreciated.

Update 1: Seems the Spring Boot Dependency was managing okhttp3.version. After updating the property to below, the error was resolved.

<properties>
    <java.version>1.8</java.version>
    <okhttp3.version>4.9.1</okhttp3.version>        
</properties>

However now there is new error:

java.lang.NoClassDefFoundError: reactor/netty/channel/BootstrapHandlers
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.lambda$build$4(NettyAsyncHttpClientBuilder.java:139)
    at reactor.netty.tcp.TcpClient.bootstrap(TcpClient.java:144)
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.lambda$build$7(NettyAsyncHttpClientBuilder.java:138)
    at reactor.netty.http.client.HttpClient.tcpConfiguration(HttpClient.java:1343)
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.build(NettyAsyncHttpClientBuilder.java:122)
    at com.app.intune.config.GraphClient.getGraphServiceClient(GraphClient.java:43)
    at com.app.intune.util.UserUtil.getUsersWithRegisteredDevicesAndSave(UserUtil.java:140)
    at com.app.intune.IntuneApplication.run(IntuneApplication.java:57)
    at org.springframework.boot.SpringApplication.callRunner(SpringApplication.java:804)
    at org.springframework.boot.SpringApplication.callRunners(SpringApplication.java:788)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:333)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1309)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1298)
    at com.app.intune.IntuneApplication.main(IntuneApplication.java:52)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:497)
    at org.springframework.boot.devtools.restart.RestartLauncher.run(RestartLauncher.java:49)
Caused by: java.lang.ClassNotFoundException: reactor.netty.channel.BootstrapHandlers
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 19 more

Answer

For anyone facing the issue, below is a solution: Project Details:
Spring Boot 2.4.4
microsoft-graph 3.0.0

Create GraphClient using below:

final ClientSecretCredential clientSecretCredential = new ClientSecretCredentialBuilder()
    .clientId(<clientId>)
    .clientSecret(<clientSecret>)
    .tenantId(<tenantId>)
    .httpClient(new NettyAsyncHttpClientBuilder().proxy(
        new ProxyOptions(ProxyOptions.Type.HTTP, new InetSocketAddress("<proxyHost>", <proxyPort>))
        .setCredentials("<proxyUser>","<proxyPassword>"))
        .build())
    .build();
    
final TokenCredentialAuthProvider tokenCredentialAuthProvider = new TokenCredentialAuthProvider(this.scopes, clientSecretCredential);
    
final GraphServiceClient graphClient = GraphServiceClient.builder().authenticationProvider(tokenCredentialAuthProvider).buildClient();

You might get additional errors as :

Exception in thread "main" java.lang.NoClassDefFoundError: reactor/netty/channel/BootstrapHandlers
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.lambda$build$4(NettyAsyncHttpClientBuilder.java:139)
    at reactor.netty.tcp.TcpClient.bootstrap(TcpClient.java:187)
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.lambda$build$7(NettyAsyncHttpClientBuilder.java:138)
    at reactor.netty.http.client.HttpClient.tcpConfiguration(HttpClient.java:1466)
    at com.azure.core.http.netty.NettyAsyncHttpClientBuilder.build(NettyAsyncHttpClientBuilder.java:122)
    at com.app.graph_test.App.main(App.java:43)
Caused by: java.lang.ClassNotFoundException: reactor.netty.channel.BootstrapHandlers
    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
    ... 6 more

The above issues occurs as microsoft-graph : 3.0.0 has below dependency tree:

microsoft-graph : 3.0.0
 - microsoft-graph-core : 2.0.0     
 -   azure-identity :1.2.3
 -     azure-core-http-netty : 1.8.0
 -       reactor-netty : 0.9.15.RELEASE

Spring boot 2.4.4 has managed dependency, hence it includes the below versions :

reactor-core : 3.4.4  
reactor-netty : 1.0.5  

The new version of reactor-netty doesnt work for microsoft-graph 3.0. Hence manually override it by adding the below in pom.xml.

<dependency>
<groupId>io.projectreactor.netty</groupId>
<artifactId>reactor-netty</artifactId>
<version>0.9.15.RELEASE</version>
</dependency>

Post this there should be no errors.