This is a companion repository for my Confluent Schema Registry & REST Proxy course on Udemy
Happy learning!
- Avro examples
- Kafka Avro Producer & Consumer
- Schema Evolutions
Learn the Confluent Schema Registry & REST Proxy
Home Page: https://www.udemy.com/confluent-schema-registry/?couponCode=GITHUB
This is a companion repository for my Confluent Schema Registry & REST Proxy course on Udemy
Happy learning!
Hello Stéphane,
I was following the instructions in the course and my generated specific class was not being found by the runnable class. I'm not very experienced in maven so I followed all the steps as described in your videos without success. Then I thought it was something on my code but after cloning this repo the same thing happened: the runnable class couldn't find the generated classes.
The way I solved it was by running mvn install
, however this was not obvious for me and I don't really understand why I had to do it if I enabled auto imports in Intellij and ran mvn clean
and mvn package
.
I'm creating this issue so that other people can find a solution when the main class doesn't recognize the generated specific classes from the .avsc
files.
in SchemaEvolutionExamples there is a camel case error and the sample fails
should be final File file = new File("customerV1.avro");
I'm creating an avro class that contains a string and a map as fields.
I can generate the avro class through maven, and i was able to create a registry in localhost:8081
.avsc file:
{
"type":"record",
"name":"AvroClass",
"namespace":"belliPack.avro",
"fields":[
{
"name":"title",
"type":"string"
},
{
"name":"map",
"type": {"type": "map", "values": "double"}
}
]
}
Schema registry returns this:
$ curl -X GET http://localhost:8081/subjects/teste1-value/versions/1
{"subject":"teste1-value","version":1,"id":42,"schema":"{"type":"record","name":"AvroClass","namespace":"belliPack.avro","fields":[{"name":"title","type":"string"},{"name":"map","type":{"type":"map","values":"double"}}]}"}
But when running my Kafka Producer have this error:
Exception in thread "Thread-1" Exception in thread "Thread-3" org.apache.kafka.common.errors.SerializationException: Error serializing Avro message
Caused by: java.net.MalformedURLException: no protocol: 127.0.0.1:8081/subjects/teste1-value/versions
at java.base/java.net.URL.(URL.java:644)
at java.base/java.net.URL.(URL.java:540)
at java.base/java.net.URL.(URL.java:487)
at io.confluent.kafka.schemaregistry.client.rest.RestService.sendHttpRequest(RestService.java:175)
at io.confluent.kafka.schemaregistry.client.rest.RestService.httpRequest(RestService.java:256)
at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:356)
at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:348)
at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:334)
at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.registerAndGetId(CachedSchemaRegistryClient.java:168)
at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.register(CachedSchemaRegistryClient.java:222)
at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.register(CachedSchemaRegistryClient.java:198)
at io.confluent.kafka.serializers.AbstractKafkaAvroSerializer.serializeImpl(AbstractKafkaAvroSerializer.java:70)
at io.confluent.kafka.serializers.KafkaAvroSerializer.serialize(KafkaAvroSerializer.java:53)
at org.apache.kafka.common.serialization.Serializer.serialize(Serializer.java:62)
at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:903)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:865)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:752)
at belliPack.Kafka.Kafka_Producer.sendData(Kafka_Producer.java:32)
at belliPack.OPC.ExtractNodeValues.run(ExtractNodeValues.java:82)
at java.base/java.lang.Thread.run(Thread.java:834)
org.apache.kafka.common.errors.SerializationException: Error serializing Avro message
Caused by: java.net.MalformedURLException: no protocol: 127.0.0.1:8081/subjects/teste1-value/versions
at java.base/java.net.URL.(URL.java:644)
at java.base/java.net.URL.(URL.java:540)
at java.base/java.net.URL.(URL.java:487)
at io.confluent.kafka.schemaregistry.client.rest.RestService.sendHttpRequest(RestService.java:175)
at io.confluent.kafka.schemaregistry.client.rest.RestService.httpRequest(RestService.java:256)
at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:356)
at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:348)
at io.confluent.kafka.schemaregistry.client.rest.RestService.registerSchema(RestService.java:334)
at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.registerAndGetId(CachedSchemaRegistryClient.java:168)
at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.register(CachedSchemaRegistryClient.java:222)
at io.confluent.kafka.schemaregistry.client.CachedSchemaRegistryClient.register(CachedSchemaRegistryClient.java:198)
at io.confluent.kafka.serializers.AbstractKafkaAvroSerializer.serializeImpl(AbstractKafkaAvroSerializer.java:70)
at io.confluent.kafka.serializers.KafkaAvroSerializer.serialize(KafkaAvroSerializer.java:53)
at org.apache.kafka.common.serialization.Serializer.serialize(Serializer.java:62)
at org.apache.kafka.clients.producer.KafkaProducer.doSend(KafkaProducer.java:903)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:865)
at org.apache.kafka.clients.producer.KafkaProducer.send(KafkaProducer.java:752)
at belliPack.Kafka.Kafka_Producer.sendData(Kafka_Producer.java:32)
at belliPack.OPC.ExtractNodeValues.run(ExtractNodeValues.java:82)
at java.base/java.lang.Thread.run(Thread.java:834)
I appreciate any help...
Thanks
This line results into the below exception:
Exception in thread "main" java.lang.NoClassDefFoundError: io/confluent/kafka/schemaregistry/client/rest/exceptions/RestClientException
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.apache.kafka.common.config.ConfigDef.parseType(ConfigDef.java:735)
at org.apache.kafka.common.config.ConfigDef.parseValue(ConfigDef.java:490)
at org.apache.kafka.common.config.ConfigDef.parse(ConfigDef.java:483)
at org.apache.kafka.common.config.AbstractConfig.<init>(AbstractConfig.java:113)
at org.apache.kafka.common.config.AbstractConfig.<init>(AbstractConfig.java:133)
at org.apache.kafka.clients.producer.ProducerConfig.<init>(ProducerConfig.java:553)
at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:289)
at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:316)
at org.apache.kafka.clients.producer.KafkaProducer.<init>(KafkaProducer.java:301)
at com.example.KafkaAvroProducerV1.main(KafkaAvroProducerV1.java:23)
Caused by: java.lang.ClassNotFoundException: io.confluent.kafka.schemaregistry.client.rest.exceptions.RestClientException
at java.net.URLClassLoader.findClass(URLClassLoader.java:387)
at java.lang.ClassLoader.loadClass(ClassLoader.java:418)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:352)
at java.lang.ClassLoader.loadClass(ClassLoader.java:351)
... 12 more
The way to resolve it is to not exclude kafka-schema-registry-client
in the respective pom file.
Hi, in kafka-avro-course/kafka-avro-v2, there are mulptiple versions of library org.xerial.snappy:snappy-java. However, according to Maven's dependency management strategy: "first declaration wins", only org.xerial.snappy:snappy-java:1.1.1.3 can be loaded, and org.xerial.snappy:snappy-java:1.1.2.6 will be shadowed.
In total, there are 4 conflicting API pairs between these two library version.
As shown in the following figure, your project expects to invoke method <org.xerial.snappy.SnappyOutputStream: write([BII)V> in library org.xerial.snappy:snappy-java:1.1.2.6 (along the original dependency path). As it has been shadowed, this method defined in org.xerial.snappy:snappy-java:1.1.1.3 is actually forced to be referenced via the following invocation path (along the actual dependency path):
<com.github.simplesteph.kafka.apps.v2.KafkaAvroJavaConsumerV2Demo: main([Ljava/lang/String;)V> /home/wwww/wangSensor/unzip/kafka-avro-course-master/kafka-avro-v2/target/classes
<org.apache.kafka.clients.consumer.KafkaConsumer: <init>(Ljava/util/Properties;)V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.apache.kafka.clients.consumer.KafkaConsumer: <init>(Ljava/util/Properties;Lorg/apache/kafka/common/serialization/Deserializer;Lorg/apache/kafka/common/serialization/Deserializer;)V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.apache.kafka.clients.consumer.KafkaConsumer: <init>(Lorg/apache/kafka/clients/consumer/ConsumerConfig;Lorg/apache/kafka/common/serialization/Deserializer;Lorg/apache/kafka/common/serialization/Deserializer;)V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.apache.kafka.clients.consumer.KafkaConsumer: close(JZ)V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.apache.kafka.clients.ClientUtils: closeQuietly(Ljava/io/Closeable;Ljava/lang/String;Ljava/util/concurrent/atomic/AtomicReference;)V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.apache.kafka.common.record.KafkaLZ4BlockOutputStream: close()V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.apache.kafka.common.record.KafkaLZ4BlockOutputStream: writeBlock()V> /home/wwww/.m2/repository/org/apache/kafka/kafka-clients/0.11.0.1/kafka-clients-0.11.0.1.jar
<org.xerial.snappy.SnappyOutputStream: write([BII)V>
Although both of these conflicting libraries contain the referenced methods (with the same signature), they have different implementations. This issue will not cause runtime crashes, but it can introduce inconsistent semantic program hehaviors----
Code snippet of <org.xerial.snappy.SnappyOutputStream: write([BII)V> in org.xerial.snappy:snappy-java:1.1.2.6 (shadowed but expected to invoke method):
@Override
public void write(byte[] b, int byteOffset, int byteLength)
throws IOException
{
if (closed) {
throw new IOException("Stream is closed");
}
int cursor = 0;
while (cursor < byteLength) {
int readLen = Math.min(byteLength - cursor, blockSize - inputCursor);
// copy the input data to uncompressed buffer
if (readLen > 0) {
System.arraycopy(b, byteOffset + cursor, inputBuffer, inputCursor, readLen);
inputCursor += readLen;
}
if (inputCursor < blockSize) {
return;
}
compressInput();
cursor += readLen;
}
}
Code snippet of <org.xerial.snappy.SnappyOutputStream: write([BII)V> in org.xerial.snappy:snappy-java:1.1.1.3 (loaded version):
@Override
public void write(byte[] b, int off, int len) throws IOException {
rawWrite(b, off, len);
}
public void rawWrite(Object array, int byteOffset, int byteLength) throws IOException {
if(inputCursor + byteLength < MIN_BLOCK_SIZE) {
// copy the input data to uncompressed buffer
Snappy.arrayCopy(array, byteOffset, byteLength, inputBuffer, inputCursor);
inputCursor += byteLength;
return;
}
compressInput();
for(int readBytes = 0; readBytes < byteLength; ) {
int inputLen = Math.min(blockSize, byteLength - readBytes);
if(!hasSufficientOutputBufferFor(inputLen)) {
dumpOutput();
}
int compressedSize = Snappy.rawCompress(array, byteOffset + readBytes, inputLen, outputBuffer, outputCursor + 4);
writeInt(outputBuffer, outputCursor, compressedSize);
outputCursor += 4 + compressedSize;
readBytes += inputLen;
}
}
The detailed informantion of the remaining 3 conflicting API pairs can be found in the following attachment.
4 conflicting API pairs in project kafka-avro-v2.txt
[INFO] com.github.simplesteph.udemy.kafka:kafka-avro-v2:jar:1.0-SNAPSHOT
[INFO] +- org.apache.avro:avro:jar:1.8.2:compile
[INFO] | +- org.codehaus.jackson:jackson-core-asl:jar:1.9.13:compile
[INFO] | +- org.codehaus.jackson:jackson-mapper-asl:jar:1.9.13:compile
[INFO] | | - (org.codehaus.jackson:jackson-core-asl:jar:1.9.13:compile - omitted for duplicate)
[INFO] | +- com.thoughtworks.paranamer:paranamer:jar:2.7:compile
[INFO] | +- org.xerial.snappy:snappy-java:jar:1.1.1.3:compile
[INFO] | +- org.apache.commons:commons-compress:jar:1.8.1:compile
[INFO] | +- org.tukaani:xz:jar:1.5:compile
[INFO] | - org.slf4j:slf4j-api:jar:1.7.7:compile
[INFO] +- org.apache.kafka:kafka-clients:jar:0.11.0.1:compile
[INFO] | +- net.jpountz.lz4:lz4:jar:1.3.0:compile
[INFO] | +- (org.xerial.snappy:snappy-java:jar:1.1.2.6:compile - omitted for conflict with 1.1.1.3)
[INFO] | - (org.slf4j:slf4j-api:jar:1.7.25:compile - omitted for conflict with 1.7.7)
[INFO] - io.confluent:kafka-avro-serializer:jar:3.3.1:compile
[INFO] +- (org.apache.avro:avro:jar:1.8.2:compile - omitted for duplicate)
[INFO] +- io.confluent:kafka-schema-registry-client:jar:3.3.1:compile
[INFO] | +- (org.apache.avro:avro:jar:1.8.2:compile - omitted for duplicate)
[INFO] | +- com.fasterxml.jackson.core:jackson-databind:jar:2.8.4:compile
[INFO] | | +- com.fasterxml.jackson.core:jackson-annotations:jar:2.8.0:compile
[INFO] | | - com.fasterxml.jackson.core:jackson-core:jar:2.8.4:compile
[INFO] | +- org.slf4j:slf4j-log4j12:jar:1.7.21:compile
[INFO] | | +- (org.slf4j:slf4j-api:jar:1.7.21:compile - omitted for conflict with 1.7.7)
[INFO] | | - log4j:log4j:jar:1.2.17:compile
[INFO] | - (io.confluent:common-utils:jar:3.3.1:compile - omitted for duplicate)
[INFO] +- io.confluent:common-config:jar:3.3.1:compile
[INFO] | +- (io.confluent:common-utils:jar:3.3.1:compile - omitted for duplicate)
[INFO] | - (org.slf4j:slf4j-api:jar:1.7.21:compile - omitted for conflict with 1.7.7)
[INFO] - io.confluent:common-utils:jar:3.3.1:compile
[INFO] +- (org.slf4j:slf4j-api:jar:1.7.21:compile - omitted for conflict with 1.7.7)
[INFO] +- org.apache.zookeeper:zookeeper:jar:3.4.10:compile
[INFO] | +- (org.slf4j:slf4j-api:jar:1.6.1:compile - omitted for conflict with 1.7.7)
[INFO] | +- (org.slf4j:slf4j-log4j12:jar:1.6.1:compile - omitted for conflict with 1.7.21)
[INFO] | +- (log4j:log4j:jar:1.2.16:compile - omitted for conflict with 1.2.17)
[INFO] | +- jline:jline:jar:0.9.94:compile
[INFO] | | - junit:junit:jar:3.8.1:compile
[INFO] | - io.netty:netty:jar:3.10.5.Final:compile
[INFO] - com.101tec:zkclient:jar:0.10:compile
[INFO] +- (org.slf4j:slf4j-api:jar:1.6.1:compile - omitted for conflict with 1.7.7)
[INFO] - (org.apache.zookeeper:zookeeper:jar:3.4.8:compile - omitted for conflict with 3.4.10)
Solution1: Declare version org.xerial.snappy:snappy-java:1.1.2.6 as a direct dependency, to override the version 1.1.1.3 (based on Maven's nearest wins loading strategy).
Solution2: reversing the dependencies (org.apache.avro:avro:jar:1.8.2 and org.apache.kafka:kafka-clients:jar:0.11.0.1) declaration order of these two libraries in pom file.
Thanks.
Best regards,
Coco
Hi Stephaane,
I was just wondering if you could add to this repository the rest-proxy files like the rest-proxy-insomnia,json
Thank you for your work!
While building pom.xml I am getting this error in both v1 and v2
Downloaded: https://repo.maven.apache.org/maven2/joda-time/joda-time/2.7/joda-time-2.7.jar (576 KB at 114.5 KB/sec)
[WARNING] Error injecting: org.apache.avro.mojo.SchemaMojo
com.google.inject.ProvisionException: Unable to provision, see the following errors:
1) Error injecting constructor, java.lang.NoClassDefFoundError: org/codehaus/jackson/JsonParseException
at org.apache.avro.mojo.SchemaMojo.<init>(Unknown Source)
while locating org.apache.avro.mojo.SchemaMojo
1 error
at com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1025)
at com.google.inject.internal.InjectorImpl.getInstance(InjectorImpl.java:1051)
at org.eclipse.sisu.space.AbstractDeferredClass.get(AbstractDeferredClass.java:48)
at com.google.inject.internal.ProviderInternalFactory.provision(ProviderInternalFactory.java:81)
at com.google.inject.internal.InternalFactoryToInitializableAdapter.provision(InternalFactoryToInitializableAdapter.java:53)
at com.google.inject.internal.ProviderInternalFactory$1.call(ProviderInternalFactory.java:65)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:115)
at org.eclipse.sisu.bean.BeanScheduler$Activator.onProvision(BeanScheduler.java:176)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:126)
at com.google.inject.internal.ProvisionListenerStackCallback.provision(ProvisionListenerStackCallback.java:68)
at com.google.inject.internal.ProviderInternalFactory.circularGet(ProviderInternalFactory.java:63)
at com.google.inject.internal.InternalFactoryToInitializableAdapter.get(InternalFactoryToInitializableAdapter.java:45)
at com.google.inject.internal.InjectorImpl$2$1.call(InjectorImpl.java:1016)
at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1092)
at com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1012)
at org.eclipse.sisu.inject.Guice4$1.get(Guice4.java:162)
at org.eclipse.sisu.inject.LazyBeanEntry.getValue(LazyBeanEntry.java:81)
at org.eclipse.sisu.plexus.LazyPlexusBean.getValue(LazyPlexusBean.java:51)
at org.codehaus.plexus.DefaultPlexusContainer.lookup(DefaultPlexusContainer.java:263)
at org.codehaus.plexus.DefaultPlexusContainer.lookup(DefaultPlexusContainer.java:255)
at org.apache.maven.plugin.internal.DefaultMavenPluginManager.getConfiguredMojo(DefaultMavenPluginManager.java:517)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:121)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:207)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:116)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:80)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:307)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:193)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:106)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:863)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:288)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:199)
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:498)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)
at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
Caused by: java.lang.NoClassDefFoundError: org/codehaus/jackson/JsonParseException
at org.apache.avro.mojo.SchemaMojo.<init>(SchemaMojo.java:41)
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:62)
at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
at com.google.inject.internal.DefaultConstructionProxyFactory$1.newInstance(DefaultConstructionProxyFactory.java:86)
at com.google.inject.internal.ConstructorInjector.provision(ConstructorInjector.java:105)
at com.google.inject.internal.ConstructorInjector.access$000(ConstructorInjector.java:32)
at com.google.inject.internal.ConstructorInjector$1.call(ConstructorInjector.java:89)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:115)
at com.google.inject.internal.ProvisionListenerStackCallback$Provision.provision(ProvisionListenerStackCallback.java:133)
at com.google.inject.internal.ProvisionListenerStackCallback.provision(ProvisionListenerStackCallback.java:68)
at com.google.inject.internal.ConstructorInjector.construct(ConstructorInjector.java:87)
at com.google.inject.internal.ConstructorBindingImpl$Factory.get(ConstructorBindingImpl.java:267)
at com.google.inject.internal.InjectorImpl$2$1.call(InjectorImpl.java:1016)
at com.google.inject.internal.InjectorImpl.callInContext(InjectorImpl.java:1103)
at com.google.inject.internal.InjectorImpl$2.get(InjectorImpl.java:1012)
... 43 more
Caused by: java.lang.ClassNotFoundException: org.codehaus.jackson.JsonParseException
at org.codehaus.plexus.classworlds.strategy.SelfFirstStrategy.loadClass(SelfFirstStrategy.java:50)
at org.codehaus.plexus.classworlds.realm.ClassRealm.unsynchronizedLoadClass(ClassRealm.java:271)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:247)
at org.codehaus.plexus.classworlds.realm.ClassRealm.loadClass(ClassRealm.java:239)
... 60 more
To fix the error below :
Could not resolve dependencies for project com.github.simplesteph.udemy.kafka:kafka-avro-v2:jar:1.0-SNAPSHOT: The following artifacts could not be resolved: io.confluent:kafka-avro-serializer:jar:3.1.1, io.confluent:kafka-schema-registry-client:jar:3.1.1, io.confluent:common-config:jar:3.1.1, io.confluent:common-utils:jar:3.1.1: Could not transfer artifact io.confluent:kafka-avro-serializer:jar:3.1.1 from/to maven-default-http-blocker (http://0.0.0.0/): Blocked mirror for repositories: [confluent (http://packages.confluent.io/maven/, default, releases+snapshots)]
Needed to change the confluent repository url with https on all pom.xml :
<!--necessary to resolve confluent dependencies-->
<repositories>
<repository>
<id>confluent</id>
<url>https://packages.confluent.io/maven/</url>
</repository>
</repositories>
In this example you are using that avro file and creat that class automatically.
so in most of the situation we need to create a class with the variables we need and from there only we need to send or receive data?
so for this situation how can i do the same avro serialization?
this class is missing
To fix the error below :
Could not resolve dependencies for project com.github.simplesteph.udemy.kafka:kafka-avro-v2:jar:1.0-SNAPSHOT: The following artifacts could not be resolved: io.confluent:kafka-avro-serializer:jar:3.1.1, io.confluent:kafka-schema-registry-client:jar:3.1.1, io.confluent:common-config:jar:3.1.1, io.confluent:common-utils:jar:3.1.1: Could not transfer artifact io.confluent:kafka-avro-serializer:jar:3.1.1 from/to maven-default-http-blocker (http://0.0.0.0/): Blocked mirror for repositories: [confluent (http://packages.confluent.io/maven/, default, releases+snapshots)]
Needed to change the confluent repository url with https on all pom.xml :
<!--necessary to resolve confluent dependencies-->
<repositories>
<repository>
<id>confluent</id>
<url>https://packages.confluent.io/maven/</url>
</repository>
</repositories>
To fix the error below :
Could not resolve dependencies for project com.github.simplesteph.udemy.kafka:kafka-avro-v2:jar:1.0-SNAPSHOT: The following artifacts could not be resolved: io.confluent:kafka-avro-serializer:jar:3.1.1, io.confluent:kafka-schema-registry-client:jar:3.1.1, io.confluent:common-config:jar:3.1.1, io.confluent:common-utils:jar:3.1.1: Could not transfer artifact io.confluent:kafka-avro-serializer:jar:3.1.1 from/to maven-default-http-blocker (http://0.0.0.0/): Blocked mirror for repositories: [confluent (http://packages.confluent.io/maven/, default, releases+snapshots)]
Needed to change the confluent repository url with https on all pom.xml :
<!--necessary to resolve confluent dependencies-->
<repositories>
<repository>
<id>confluent</id>
<url>https://packages.confluent.io/maven/</url>
</repository>
</repositories>
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