“林子雨大数据” 实验3 HBase操作与接口编程
环境搭建
VM虚拟机和Ubuntu系统的安装
在Windows中使用VirtualBox安装Ubuntu虚拟机(2020年7月版本)_厦大数据库实验室博客 (xmu.edu.cn)
Hadoop安装(伪分布式)
Hadoop3.1.3安装教程_单机/伪分布式配置_Hadoop3.1.3/Ubuntu18.04(16.04)_厦大数据库实验室博客 (xmu.edu.cn)
HBase安装(伪分布式)
HBase2.2.2安装和编程实践指南_厦大数据库实验室博客 (xmu.edu.cn)
通过NAT转发使本地主机连接虚拟机
PowerShell SSH 连接 VirtualBox Ubuntu 虚拟机的具体步骤 - 小能日记 - 博客园 (cnblogs.com)
文件传输工具
FlashFXP - Secure FTP Client Software for Windows. Upload, Download, and Synchronize your files.
在VSCODE中使用SSH进行远程开发
在VScode中使用SSH进行远程开发_vscode ssh_Shipmaster_23的博客-CSDN博客
Linux中安装go环境并运行
【golang】linux中安装go环境并运行_linux 运行golang_沉默小管的博客-CSDN博客
理解Hbase
我终于看懂了HBase,太不容易了... - 知乎 (zhihu.com)
第三方软件包
tsuna/gohbase: Pure-Go HBase client (github.com)
hrpc package - github.com/tsuna/gohbase/hrpc - Go Packages
gin框架 · Go语言中文文档 (topgoer.com)
遇到过的问题
go build command fails with "$GOPATH/go.mod exists but should not" · Issue #38896 · golang/go (github.com)
Infinite Getting code actions from ''Go', 'Go', 'Go'' on save · Issue #3105 · microsoft/vscode-go (github.com)
Linux 查看端口占用情况 | 菜鸟教程 (runoob.com)
接口编程
实验过程
创建三个表
对应第2题答案- create 'student','S_No','S_Name','S_Sex','S_Age'
- put 'student','s001','S_No','2015001'
- put 'student','s001','S_Name','zhangsan'
- put 'student','s001','S_Sex','male'
- put 'student','s001','S_Age','23'
- put 'student','s002','S_No','2015002'
- put 'student','s002','S_Name','Mary'
- put 'student','s002','S_Sex','female'
- put 'student','s002','S_Age','22'
- put 'student','s003','S_No','2015003'
- put 'student','s003','S_Name','Lisi'
- put 'student','s003','S_Sex','male'
- put 'student','s003','S_Age','24'
- create 'course','C_No','C_Name','C_Credit'
- put 'course','c001','C_No','123001'
- put 'course','c001','C_Name','Math'
- put 'course','c001','C_Credit','2.0'
- put 'course','c002','C_No','123002'
- put 'course','c002','C_Name','Computer'
- put 'course','c002','C_Credit','5.0'
- put 'course','c003','C_No','123003'
- put 'course','c003','C_Name','English'
- put 'course','c003','C_Credit','3.0'
- create 'SC','SC_Sno','SC_Cno','SC_Score'
- put 'SC','sc001','SC_Sno','2015001'
- put 'SC','sc001','SC_Cno','123001'
- put 'SC','sc001','SC_Score','86'
- put 'SC','sc002','SC_Sno','2015001'
- put 'SC','sc002','SC_Cno','123002'
- put 'SC','sc002','SC_Score','77'
- put 'SC','sc003','SC_Sno','2015002'
- put 'SC','sc003','SC_Cno','123002'
- put 'SC','sc003','SC_Score','77'
- put 'SC','sc004','SC_Sno','2015002'
- put 'SC','sc004','SC_Cno','123003'
- put 'SC','sc004','SC_Score','99'
- put 'SC','sc005','SC_Sno','2015003'
- put 'SC','sc005','SC_Cno','123001'
- put 'SC','sc005','SC_Score','98'
- put 'SC','sc006','SC_Sno','2015003'
- put 'SC','sc006','SC_Cno','123002'
- put 'SC','sc006','SC_Score','95'
复制代码 后端编程
后端在启动时分别与本地HBase建立管理员客户端、普通客户端的连接。管理员客户端管理所有表,普通客户端管理表数据的增删改查。并启动HTTP服务提供一系列API接口。- package variable
- import "github.com/tsuna/gohbase"
- var AdminClient gohbase.AdminClient
- var Client gohbase.Client
复制代码- package main
- import (
- "github.com/gin-gonic/gin"
- "github.com/tsuna/gohbase"
- "wolflong.com/hbase_gin/router"
- "wolflong.com/hbase_gin/variable"
- )
- func init() {
- variable.AdminClient = gohbase.NewAdminClient("127.0.0.1")
- variable.Client = gohbase.NewClient("127.0.0.1")
- }
- func main() {
- r := gin.Default()
- router.Router(r)
- r.Run(":1313")
- }
复制代码 给定一个处理错误的通用方法- package controller
- import "github.com/gin-gonic/gin"
- func checkError(err error, c *gin.Context, handlers ...gin.HandlerFunc) {
- if err != nil {
- c.JSON(500, gin.H{"error": "致命错误", "back": err.Error()})
- panic(err)
- }
- }
复制代码 1.1 列出所有表的相关信息
HBase Shell 对应代码从管理客户端发出请求,获取所有表,遍历表将表的命名空间与表名存储至切片中以json格式返回- type table struct {
- Namespace string `json:"namespace"`
- Qualifier string `json:"qualifier"`
- }
- func ShowTableList(c *gin.Context) {
- var tables []table
- t, err := hrpc.NewListTableNames(context.Background())
- checkError(err, c)
- res, err := variable.AdminClient.ListTableNames(t)
- checkError(err, c)
- for _, v := range res {
- tables = append(tables, table{string(v.GetNamespace()), string(v.GetQualifier())})
- }
- fmt.Println(tables)
- c.JSON(200, tables)
- }
复制代码 测试结果- [
- {
- "namespace": "default",
- "qualifier": "SC"
- },
- {
- "namespace": "default",
- "qualifier": "course"
- },
- {
- "namespace": "default",
- "qualifier": "student"
- },
- {
- "namespace": "default",
- "qualifier": "test"
- }
- ]
复制代码 1.2 打印指定表的所有记录数据
HBase Shell 对应代码
获取请求参数table,从普通客户端发出请求,获取scanner,遍历scanner直到io.EOF。请注意,当查询的表没数据时,第一条拿到的是nil数据,需要进行判断。- func ShowTableRows(c *gin.Context) {
- var Cells [][]*hrpc.Cell
- t, err := hrpc.NewScan(context.Background(), []byte(c.Query("table")))
- checkError(err, c)
- res := variable.Client.Scan(t)
- row, err := res.Next()
- for err != io.EOF && row != nil {
- Cells = append(Cells, row.Cells)
- fmt.Println(row.Cells)
- row, err = res.Next()
- }
- c.JSON(200, Cells)
- }
复制代码 localhost:1313/TableRows?table=course 测试结果。
请注意,Gin框架在转换二进制数据时使用BASE64编码,使得控制字符在网络上正常传输。- [
- [
- {
- "row": "YzAwMQ==",
- "family": "Q19DcmVkaXQ=",
- "timestamp": 1680431640294,
- "cell_type": 4,
- "value": "Mi4w"
- },
- {
- "row": "YzAwMQ==",
- "family": "Q19DcmVkaXQ=",
- "qualifier": "bmV3",
- "timestamp": 1680432352886,
- "cell_type": 4,
- "value": "NS4w"
- },
- {
- "row": "YzAwMQ==",
- "family": "Q19OYW1l",
- "timestamp": 1680431640279,
- "cell_type": 4,
- "value": "TWF0aA=="
- },
- {
- "row": "YzAwMQ==",
- "family": "Q19Obw==",
- "timestamp": 1680431640250,
- "cell_type": 4,
- "value": "MTIzMDAx"
- }
- ],
- [
- {
- "row": "YzAwMg==",
- "family": "Q19DcmVkaXQ=",
- "timestamp": 1680431640328,
- "cell_type": 4,
- "value": "NS4w"
- },
- {
- "row": "YzAwMg==",
- "family": "Q19OYW1l",
- "timestamp": 1680431640318,
- "cell_type": 4,
- "value": "Q29tcHV0ZXI="
- },
- {
- "row": "YzAwMg==",
- "family": "Q19Obw==",
- "timestamp": 1680431640305,
- "cell_type": 4,
- "value": "MTIzMDAy"
- }
- ],
- [
- {
- "row": "YzAwMw==",
- "family": "Q19DcmVkaXQ=",
- "timestamp": 1680431640363,
- "cell_type": 4,
- "value": "My4w"
- },
- {
- "row": "YzAwMw==",
- "family": "Q19OYW1l",
- "timestamp": 1680431640352,
- "cell_type": 4,
- "value": "RW5nbGlzaA=="
- },
- {
- "row": "YzAwMw==",
- "family": "Q19Obw==",
- "timestamp": 1680431640343,
- "cell_type": 4,
- "value": "MTIzMDAz"
- }
- ]
- ]
复制代码 1.3 向已创建好的表添加和删除指定的列族或列
HBase Shell 对应代码- put 'course','c001','C_Credit:new','5.0'
- delete 'course','c001','C_Credit:new'
复制代码 使用普通客户端进行put操作,需要准备一个item数据包含当前操作的列族或列以及对应的值。支持覆盖重写与新增。- func TableInsertRowCol(c *gin.Context) {
- table := c.PostForm("table")
- rowKey := c.PostForm("rowKey")
- colFamily := c.PostForm("colFamily")
- col := c.PostForm("col")
- val := c.PostForm("val")
- var item map[string]map[string][]byte = make(map[string]map[string][]byte)
- item[colFamily] = make(map[string][]byte)
- item[colFamily][col] = []byte(val)
- fmt.Println(item)
- t, err := hrpc.NewPutStr(context.Background(), table, rowKey, item)
- checkError(err, c)
- res, err := variable.Client.Put(t)
- checkError(err, c)
- c.JSON(200, res)
- }
复制代码 测试结果- {
- "Cells": null,
- "Stale": false,
- "Partial": false,
- "Exists": null
- }
复制代码
删除列族或列,不需要val数据。列可以为空字符串,仅删除列族,不为空时则删除指定的列- func TableDeleteRowCol(c *gin.Context) {
- table := c.PostForm("table")
- rowKey := c.PostForm("rowKey")
- colFamily := c.PostForm("colFamily")
- col := c.PostForm("col")
- // val := c.PostForm("val")
- var item map[string]map[string][]byte = make(map[string]map[string][]byte)
- item[colFamily] = make(map[string][]byte)
- item[colFamily][col] = []byte{}
- fmt.Println(item)
- t, err := hrpc.NewPutStr(context.Background(), table, rowKey, item)
- checkError(err, c)
- res, err := variable.Client.Delete(t)
- checkError(err, c)
- c.JSON(200, res)
- }
复制代码 1.4 清空指定表的所有数据
HBase Shell 对应代码先disable表,再删除表。- func TableDelete(c *gin.Context) {
- t := hrpc.NewDisableTable(context.Background(), []byte(c.Query("table")))
- err := variable.AdminClient.DisableTable(t)
- checkError(err, c)
- t2 := hrpc.NewDeleteTable(context.Background(), []byte(c.Query("table")))
- err = variable.AdminClient.DeleteTable(t2)
- checkError(err, c)
- c.JSON(200, gin.H{"result": "删除成功"})
- }
复制代码 1.5 统计表的行数
HBase Shell 对应代码修改1.2的代码- func ShowTableRowsCount(c *gin.Context) {
- var count int
- t, err := hrpc.NewScan(context.Background(), []byte(c.Query("table")))
- checkError(err, c)
- res := variable.Client.Scan(t)
- row, err := res.Next()
- for err != io.EOF && row != nil {
- count++
- row, err = res.Next()
- }
- c.JSON(200, count)
- }
复制代码 localhost:1313/TableRowsCount?table=course 测试结果3.1 创建表
- func TableCreate(c *gin.Context) {
- table := c.PostForm("table")
- fs := c.PostForm("fields")
- var fields []string
- // fmt.Println(table, fs)
- err := json.Unmarshal([]byte(fs), &fields)
- checkError(err, c)
- // 验证是否存在表
- flag := false
- t, err := hrpc.NewListTableNames(context.Background())
- checkError(err, c)
- res, err := variable.AdminClient.ListTableNames(t)
- checkError(err, c)
- for _, v := range res {
- if string(v.GetQualifier()) == table {
- flag = true
- }
- }
- // 如存在删除表
- if flag {
- t := hrpc.NewDisableTable(context.Background(), []byte(table))
- err := variable.AdminClient.DisableTable(t)
- checkError(err, c)
- t2 := hrpc.NewDeleteTable(context.Background(), []byte(table))
- err = variable.AdminClient.DeleteTable(t2)
- checkError(err, c)
- }
- // 插入新表
- var items map[string]map[string]string = make(map[string]map[string]string)
- for _, v := range fields {
- items[v] = make(map[string]string)
- }
- t2 := hrpc.NewCreateTable(context.Background(), []byte(table), items)
- err = variable.AdminClient.CreateTable(t2)
- checkError(err, c)
- c.JSON(200, gin.H{"result": "创建成功"})
- }
复制代码 通过1.1函数接口我们可知test表已经存在,现在我们使用3.1函数接口重新创建该表,并为接下来的3.2函数接口调用做准备。
3.2 新增记录
为了增强健壮性,我们需要判断传入的fields、values参数个数是否一致,否则应当主动报错。- func TableInsertRow(c *gin.Context) {
- table := c.PostForm("table")
- rowKey := c.PostForm("rowKey")
- fs := c.PostForm("fields")
- vs := c.PostForm("values")
- var fields []string
- var values []string
- err := json.Unmarshal([]byte(fs), &fields)
- checkError(err, c)
- err = json.Unmarshal([]byte(vs), &values)
- checkError(err, c)
- if len(fields) != len(values) {
- checkError(fmt.Errorf("数量不一致"), c)
- }
- var item map[string]map[string][]byte = make(map[string]map[string][]byte)
- for i, v := range fields {
- vs := strings.Split(v, ":")
- item[vs[0]] = make(map[string][]byte)
- if len(vs) > 1 {
- item[vs[0]][vs[1]] = []byte(values[i])
- } else {
- item[vs[0]][""] = []byte(values[i])
- }
- }
- fmt.Println(item)
- t, err := hrpc.NewPutStr(context.Background(), table, rowKey, item)
- checkError(err, c)
- res, err := variable.Client.Put(t)
- checkError(err, c)
- c.JSON(200, res)
- }
复制代码 3.3 通过列过滤数据
使用scanner实现,也可以通过过滤器实现。- // TODO USE FILTER
- type item struct {
- Row string `json:"row"`
- Family string `json:"family"`
- Qualifier string `json:"qualifier"`
- Timestamp *uint64 `json:"timestamp"`
- Cell_type *pb.CellType `json:"cell_type"`
- Value string `json:"value"`
- }
- func TableColumnScan(c *gin.Context) {
- table := c.Query("table")
- column := c.Query("column")
- vs := strings.Split(column, ":")
- var items []item
- t, err := hrpc.NewScan(context.Background(), []byte(table))
- checkError(err, c)
- res := variable.Client.Scan(t)
- row, err := res.Next()
- for err != io.EOF && row != nil {
- for _, v := range row.Cells {
- if string(v.Family) != vs[0] {
- continue
- }
- if len(vs) > 1 {
- if string(v.Qualifier) != vs[1] {
- continue
- }
- }
- fmt.Println(row.Cells)
- items = append(items, item{
- Row: string(v.Row),
- Family: string(v.Family),
- Qualifier: string(v.Qualifier),
- Timestamp: v.Timestamp,
- Cell_type: v.CellType,
- Value: string(v.Value),
- })
- }
- row, err = res.Next()
- }
- c.JSON(200, items)
- }
复制代码 再执行一遍1.3添加列的函数,调用接口,执行结果如下。
localhost:1313/TableColumnScan?table=course&column=C_Credit- [
- {
- "row": "c001",
- "family": "C_Credit",
- "qualifier": "",
- "timestamp": 1680431640294,
- "cell_type": 4,
- "value": "2.0"
- },
- {
- "row": "c001",
- "family": "C_Credit",
- "qualifier": "new",
- "timestamp": 1680434951646,
- "cell_type": 4,
- "value": "5.0"
- },
- {
- "row": "c002",
- "family": "C_Credit",
- "qualifier": "",
- "timestamp": 1680431640328,
- "cell_type": 4,
- "value": "5.0"
- },
- {
- "row": "c003",
- "family": "C_Credit",
- "qualifier": "",
- "timestamp": 1680431640363,
- "cell_type": 4,
- "value": "3.0"
- }
- ]
复制代码 localhost:1313/TableColumnScan?table=course&column=C_Credit:new- [
- {
- "row": "c001",
- "family": "C_Credit",
- "qualifier": "new",
- "timestamp": 1680434951646,
- "cell_type": 4,
- "value": "5.0"
- }
- ]
复制代码 3.4 修改行数据
与 1.3 函数代码一致
3.5 删除表指定记录
- package controller
- import (
- "context"
- "github.com/gin-gonic/gin"
- "github.com/tsuna/gohbase/hrpc"
- "wolflong.com/hbase_gin/variable"
- )
- func TableDeleteRow(c *gin.Context) {
- table := c.PostForm("table")
- rowKey := c.PostForm("rowKey")
- t, err := hrpc.NewDelStr(context.Background(), table, rowKey, nil)
- checkError(err, c)
- res, err := variable.Client.Delete(t)
- checkError(err, c)
- c.JSON(200, res)
- }
复制代码- {
- "Cells": null,
- "Stale": false,
- "Partial": false,
- "Exists": null
- }
复制代码 再次调用1.5函数接口,执行结果符合预期。
总结
装环境2小时,代码和文档编写4.5小时,代码编写过程中查阅官方文档和解决问题的时间为3小时。
总共花费6.5个小时,共编写333行代码,56行表数据。
代码编写能力得到了提升。提高了自己对HBase的理解,作为一个典型的NoSQL数据库,其一大优点是可在廉价PC服务器上搭建起大规模结构化存储集群,并提供易使用的HBase Shell操作数据集,水平扩展方便。
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