kafka ApiVersionsRequest 源码

kafka ApiVersionsRequest 代码

文件路径：/clients/src/main/java/org/apache/kafka/common/requests/ApiVersionsRequest.java

/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements. See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License. You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.kafka.common.requests;

import java.util.regex.Pattern;
import org.apache.kafka.common.message.ApiVersionsRequestData;
import org.apache.kafka.common.message.ApiVersionsResponseData;
import org.apache.kafka.common.message.ApiVersionsResponseData.ApiVersionCollection;
import org.apache.kafka.common.protocol.ApiKeys;
import org.apache.kafka.common.protocol.ByteBufferAccessor;
import org.apache.kafka.common.protocol.Errors;
import org.apache.kafka.common.utils.AppInfoParser;

import java.nio.ByteBuffer;

public class ApiVersionsRequest extends AbstractRequest {

    public static class Builder extends AbstractRequest.Builder<ApiVersionsRequest> {
        private static final String DEFAULT_CLIENT_SOFTWARE_NAME = "apache-kafka-java";

        private static final ApiVersionsRequestData DATA = new ApiVersionsRequestData()
            .setClientSoftwareName(DEFAULT_CLIENT_SOFTWARE_NAME)
            .setClientSoftwareVersion(AppInfoParser.getVersion());

        public Builder() {
            super(ApiKeys.API_VERSIONS);
        }

        public Builder(short version) {
            super(ApiKeys.API_VERSIONS, version);
        }

        @Override
        public ApiVersionsRequest build(short version) {
            return new ApiVersionsRequest(DATA, version);
        }

        @Override
        public String toString() {
            return DATA.toString();
        }
    }

    private static final Pattern SOFTWARE_NAME_VERSION_PATTERN = Pattern.compile("[a-zA-Z0-9](?:[a-zA-Z0-9\\-.]*[a-zA-Z0-9])?");

    private final Short unsupportedRequestVersion;

    private final ApiVersionsRequestData data;

    public ApiVersionsRequest(ApiVersionsRequestData data, short version) {
        this(data, version, null);
    }

    public ApiVersionsRequest(ApiVersionsRequestData data, short version, Short unsupportedRequestVersion) {
        super(ApiKeys.API_VERSIONS, version);
        this.data = data;

        // Unlike other request types, the broker handles ApiVersion requests with higher versions than
        // supported. It does so by treating the request as if it were v0 and returns a response using
        // the v0 response schema. The reason for this is that the client does not yet know what versions
        // a broker supports when this request is sent, so instead of assuming the lowest supported version,
        // it can use the most recent version and only fallback to the old version when necessary.
        this.unsupportedRequestVersion = unsupportedRequestVersion;
    }

    public boolean hasUnsupportedRequestVersion() {
        return unsupportedRequestVersion != null;
    }

    public boolean isValid() {
        if (version() >= 3) {
            return SOFTWARE_NAME_VERSION_PATTERN.matcher(data.clientSoftwareName()).matches() &&
                SOFTWARE_NAME_VERSION_PATTERN.matcher(data.clientSoftwareVersion()).matches();
        } else {
            return true;
        }
    }

    @Override
    public ApiVersionsRequestData data() {
        return data;
    }

    @Override
    public ApiVersionsResponse getErrorResponse(int throttleTimeMs, Throwable e) {
        ApiVersionsResponseData data = new ApiVersionsResponseData()
            .setErrorCode(Errors.forException(e).code());

        if (version() >= 1) {
            data.setThrottleTimeMs(throttleTimeMs);
        }

        // Starting from Apache Kafka 2.4 (KIP-511), ApiKeys field is populated with the supported
        // versions of the ApiVersionsRequest when an UNSUPPORTED_VERSION error is returned.
        if (Errors.forException(e) == Errors.UNSUPPORTED_VERSION) {
            ApiVersionCollection apiKeys = new ApiVersionCollection();
            apiKeys.add(ApiVersionsResponse.toApiVersion(ApiKeys.API_VERSIONS));
            data.setApiKeys(apiKeys);
        }

        return new ApiVersionsResponse(data);
    }

    public static ApiVersionsRequest parse(ByteBuffer buffer, short version) {
        return new ApiVersionsRequest(new ApiVersionsRequestData(new ByteBufferAccessor(buffer), version), version);
    }

}

相关信息

kafka 源码目录

相关文章

kafka AbstractControlRequest 源码

kafka AbstractRequest 源码

kafka AbstractRequestResponse 源码

kafka AbstractResponse 源码

kafka AddOffsetsToTxnRequest 源码

kafka AddOffsetsToTxnResponse 源码

kafka AddPartitionsToTxnRequest 源码

kafka AddPartitionsToTxnResponse 源码

kafka AllocateProducerIdsRequest 源码

kafka AllocateProducerIdsResponse 源码