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Springboot 之 Filter 实现 Gzip 压缩超大 json 对象

SpringBoot

简介
在项目中，存在传递超大 json 数据的场景 。直接传输超大 json 数据的话，有以下两个弊端
 

  • 占用网络带宽，而有些云产品就是按照带宽来计费的，间接浪费了钱
  • 传输数据大导致网络传输耗时较长 为了避免直接传输超大 json 数据，可以对 json 数据进行 Gzip 压缩后，再进行网络传输 。
  • 请求头添加 Content-Encoding 标识，传输的数据进行过压缩
  • Servlet Filter 拦截请求，对压缩过的数据进行解压
  • HttpServletRequestWrApper 包装，把解压的数据写入请求体
pom.xml 引入依赖4.0.0com.oliverequest-uncompression0.0.1-SNAPSHOTjarrequest-uncompressionhttp://maven.Apache.orgorg.springframework.bootspring-boot-starter-parent2.5.14UTF-888org.springframework.bootspring-boot-starter-testtestorg.projectlomboklombokorg.springframework.bootspring-boot-starter-webcom.alibaba.fastjson2fastjson22.0.14commons-iocommons-io2.9.0创建压缩工具类 
【Springboot 之 Filter 实现 Gzip 压缩超大 json 对象】GzipUtils 类提供压缩解压相关方法
package com.olive.utils;import com.alibaba.fastjson2.JSON;import com.olive.vo.ArticleRequestVO;import lombok.extern.slf4j.Slf4j;import org.apache.commons.io.FileUtils;import JAVA.io.*;import java.util.zip.GZIPInputStream;import java.util.zip.GZIPOutputStream;@Slf4jpublic class GzipUtils {private static final String GZIP_ENCODE_UTF_8 = "UTF-8";* 字符串压缩为GZIP字节数组* @param str* @returnpublic static byte[] compress(String str) {return compress(str, GZIP_ENCODE_UTF_8);* 字符串压缩为GZIP字节数组* @param str* @param encoding* @returnpublic static byte[] compress(String str, String encoding) {if (str == null || str.length() == 0) {return null;ByteArrayOutputStream out = new ByteArrayOutputStream();GZIPOutputStream gzip = null;try {gzip = new GZIPOutputStream(out);gzip.write(str.getBytes(encoding));} catch (IOException e) {log.error("compress>>", e);}finally {if(gzip!=null){try {gzip.close();} catch (IOException e) {return out.toByteArray();* GZIP解压缩* @param bytes* @returnpublic static byte[] uncompress(byte[] bytes) {if (bytes == null || bytes.length == 0) {return null;ByteArrayOutputStream out = new ByteArrayOutputStream();ByteArrayInputStream in = new ByteArrayInputStream(bytes);GZIPInputStream unGzip = null;try {unGzip = new GZIPInputStream(in);byte[] buffer = new byte[256];int n;while ((n = unGzip.read(buffer)) >= 0) {out.write(buffer, 0, n);} catch (IOException e) {log.error("uncompress>>", e);}finally {if(unGzip!=null){try {unGzip.close();} catch (IOException e) {return out.toByteArray();* 解压并返回String* @param bytes* @returnpublic static String uncompressToString(byte[] bytes) throws IOException {return uncompressToString(bytes, GZIP_ENCODE_UTF_8);* @param bytes* @returnpublic static byte[] uncompressToByteArray(byte[] bytes) throws IOException {return uncompressToByteArray(bytes, GZIP_ENCODE_UTF_8);* 解压成字符串* @param bytes 压缩后的字节数组* @param encoding 编码方式* @return 解压后的字符串public static String uncompressToString(byte[] bytes, String encoding) throws IOException {byte[] result = uncompressToByteArray(bytes, encoding);return new String(result);* 解压成字节数组* @param bytes* @param encoding* @returnpublic static byte[] uncompressToByteArray(byte[] bytes, String encoding) throws IOException {if (bytes == null || bytes.length == 0) {return null;ByteArrayOutputStream out = new ByteArrayOutputStream();ByteArrayInputStream in = new ByteArrayInputStream(bytes);GZIPInputStream unGzip = null;try {unGzip = new GZIPInputStream(in);byte[] buffer = new byte[256];int n;while ((n = unGzip.read(buffer)) >= 0) {out.write(buffer, 0, n);return out.toByteArray();} catch (IOException e) {log.error("uncompressToByteArray>>", e);throw new IOException("解压缩失败！");}finally {if(unGzip!=null){unGzip.close();* 将字节流转换成文件* @param filename* @param data* @throws Exceptionpublic static void saveFile(String filename, byte[] data) throws Exception {FileOutputStream fos = null;try {if (data != null) {String filepath = "/" + filename;File file = new File(filepath);if (file.exists()) {file.delete();fos = new FileOutputStream(file);fos.write(data, 0, data.length);fos.flush();System.out.println(file);}catch (Exception e){throw e;}finally {if(fos!=null){fos.close();对Request进行包装
UnZipRequestWrapper 读取输入流，然进行解压；解压完后，再把解压出来的数据封装到输入流中 。
package com.olive.filter;import com.olive.utils.GzipUtils;import lombok.extern.slf4j.Slf4j;import javax.servlet.ReadListener;import javax.servlet.ServletInputStream;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletRequestWrapper;import java.io.*;* Json String 经过压缩后保存为二进制文件 -> 解压缩后还原成 Jso nString转换成byte[]写回body中@Slf4jpublic class UnZipRequestWrapper extends HttpServletRequestWrapper {private final byte[] bytes;public UnZipRequestWrapper(HttpServletRequest request) throws IOException {super(request);try (BufferedInputStream bis = new BufferedInputStream(request.getInputStream());ByteArrayOutputStream baos = new ByteArrayOutputStream()) {final byte[] body;byte[] buffer = new byte[1024];int len;while ((len = bis.read(buffer)) > 0) {baos.write(buffer, 0, len);body = baos.toByteArray();if (body.length == 0) {log.info("Body无内容，无需解压");bytes = body;return;this.bytes = GzipUtils.uncompressToByteArray(body);} catch (IOException ex) {log.error("解压缩步骤发生异常！", ex);throw ex;@Overridepublic ServletInputStream getInputStream() throws IOException {final ByteArrayInputStream byteArrayInputStream = new ByteArrayInputStream(bytes);return new ServletInputStream() {@Overridepublic boolean isFinished() {return false;@Overridepublic boolean isReady() {return false;@Overridepublic void setReadListener(ReadListener readListener) {public int read() throws IOException {return byteArrayInputStream.read();@Overridepublic BufferedReader getReader() throws IOException {return new BufferedReader(new InputStreamReader(this.getInputStream()));


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