In io.grpc.internal.ManagedChannelImplBuilder <https://github.com/grpc/grpc-java/blob/master/core/src/main/java/io/grpc/internal/ManagedChannelImplBuilder.java#L824> it does a *provider = nameResolverRegistry.getProviderForScheme(targetUri.getScheme());* The NameResolverRegistry has 2 entries when I tried with localhost url: "dns" -> DnsNameResolverProvider and "unix" -> UdsNameResolverProvider.
For *localhost *java.net.URI getScheme will return null so the ManagedChannelImplBuilder will fallback <https://github.com/grpc/grpc-java/blob/master/core/src/main/java/io/grpc/internal/ManagedChannelImplBuilder.java#L831> to the default scheme. The default scheme is taken from the name resolver provider with the highest priority which is *DnsNameResolverProvider *in this case, whose scheme is *dns.* In your case when you run from the command line apparently only the *UdsNameResolverProvider* gets registered but not the *DnsNameResolverProvider, *and produces a socket address type not supported by Netty. Can you run with fine logging enabled so that it prints why a name resolver provider could not be loaded here <https://github.com/grpc/grpc-java/blob/master/api/src/main/java/io/grpc/NameResolverRegistry.java#L137> ? On Wednesday, May 22, 2024 at 9:33:43 PM UTC+5:30 Akash Sinha wrote: > Hello Everyone, > > I am trying to build a JAVA based gRPC client that tries to communicate > with Python based gRPC server. I am getting the following exception when I > run the code from terminal using the JAR file. > > Exception in thread "main" > io.grpc.ManagedChannelRegistry$ProviderNotFoundException: > io.grpc.netty.shaded.io.grpc.netty.NettyChannelProvider: does not support 1 > or more of [class > io.grpc.netty.shaded.io.netty.channel.unix.DomainSocketAddress] > > at > io.grpc.ManagedChannelRegistry.newChannelBuilder(ManagedChannelRegistry.java:204) > > at > io.grpc.ManagedChannelRegistry.newChannelBuilder(ManagedChannelRegistry.java:155) > > at io.grpc.Grpc.newChannelBuilder(Grpc.java:101) > > The error happens while executing the following code: > String target = "localhost:"+port; > > ManagedChannel channel = Grpc.newChannelBuilder(target, > InsecureChannelCredentials.create()).build(); > > However, the code runs fine when running the main class from the IDE. I > have created the fat jar file using maven. Following is my pom.xml file. > > <?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>org.example</groupId> > <artifactId>DummyEnv</artifactId> > <version>1.0-SNAPSHOT</version> > <dependencies> > <dependency> > <groupId>io.grpc</groupId> > <artifactId>grpc-netty-shaded</artifactId> > <version>1.63.0</version> > <scope>runtime</scope> > </dependency> > <dependency> > <groupId>io.grpc</groupId> > <artifactId>grpc-protobuf</artifactId> > <version>1.63.0</version> > </dependency> > <dependency> > <groupId>io.grpc</groupId> > <artifactId>grpc-stub</artifactId> > <version>1.63.0</version> > </dependency> > <dependency> <!-- necessary for Java 9+ --> > <groupId>org.apache.tomcat</groupId> > <artifactId>annotations-api</artifactId> > <version>6.0.53</version> > <scope>provided</scope> > </dependency> > > > </dependencies> > <properties> > <maven.compiler.source>21</maven.compiler.source> > <maven.compiler.target>21</maven.compiler.target> > <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> > </properties> > > <build> > <extensions> > <extension> > <groupId>kr.motd.maven</groupId> > <artifactId>os-maven-plugin</artifactId> > <version>1.7.1</version> > </extension> > </extensions> > <plugins> > <plugin> > <groupId>org.xolstice.maven.plugins</groupId> > <artifactId>protobuf-maven-plugin</artifactId> > <version>0.6.1</version> > <configuration> > <protocArtifact > >com.google.protobuf:protoc:3.25.1:exe:${os.detected.classifier}</ > protocArtifact> > <pluginId>grpc-java</pluginId> > <pluginArtifact > >io.grpc:protoc-gen-grpc-java:1.63.0:exe:${os.detected.classifier}</ > pluginArtifact> > </configuration> > <executions> > <execution> > <goals> > <goal>compile</goal> > <goal>compile-custom</goal> > </goals> > </execution> > </executions> > </plugin> > > <plugin> > <groupId>org.apache.maven.plugins</groupId> > <artifactId>maven-assembly-plugin</artifactId> > <version>3.7.1</version> > <configuration> > <descriptorRefs> > <descriptorRef>jar-with-dependencies</descriptorRef> > </descriptorRefs> > </configuration> > <executions> > <execution> > <id>assemble-all</id> > <phase>package</phase> > <goals> > <goal>single</goal> > </goals> > </execution> > </executions> > </plugin> > </plugins> > </build> > </project> > > Can someone please help me in debugging this issue? > > Thanks :) > > -- You received this message because you are subscribed to the Google Groups "grpc.io" group. To unsubscribe from this group and stop receiving emails from it, send an email to grpc-io+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/grpc-io/120f281f-4dd7-4e50-814f-72bd478e5d70n%40googlegroups.com.
