“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

func Router(r *gin.Engine) {
	r.GET("/", controller.HelloWorld)
	r.GET("/TableList", controller.ShowTableList)              // 1.1
	r.GET("/TableRows", controller.ShowTableRows)              // 1.2
	r.POST("/TableInsertRowCol", controller.TableInsertRowCol) // 1.3
	r.POST("/TableDeleteRowCol", controller.TableDeleteRowCol) // 1.3
	r.GET("/TableTruncate", controller.TableTruncate)          // 1.4
	r.GET("/TableRowsCount", controller.ShowTableRowsCount)    // 1.5
	r.POST("/TableCreate", controller.TableCreate)             // 3.1
	r.POST("/TableInsertRow", controller.TableInsertRow)       // 3.2
	r.GET("/TableColumnScan", controller.TableColumnScan)      // 3.3
	r.POST("/TableModifyData", controller.TableInsertRowCol)   // 3.4 same as 1.3
	r.POST("/TableDeleteRow", controller.TableDeleteRow)       // 3.5
}

实验过程

启动服务

ssh xiaoneng@127.0.0.1 -p 10022

cd /usr/local/hadoop
./sbin/start-dfs.sh

cd /usr/local/hbase
bin/start-hbase.sh

cd /usr/local/hbase
bin/hbase shell

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'

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

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")
}

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)
	}
}

1.1 列出所有表的相关信息

HBase Shell 对应代码

list

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)
}

测试结果

[
    {
        "namespace": "default",
        "qualifier": "SC"
    },
    {
        "namespace": "default",
        "qualifier": "course"
    },
    {
        "namespace": "default",
        "qualifier": "student"
    },
    {
        "namespace": "default",
        "qualifier": "test"
    }
]

1.2 打印指定表的所有记录数据

HBase Shell 对应代码

scan "course"

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)
}

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"
        }
    ]
]

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'

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)
}

测试结果

{
    "Cells": null,
    "Stale": false,
    "Partial": false,
    "Exists": null
}

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.NewDelStr(context.Background(), table, rowKey, item)
	checkError(err, c)
	res, err := variable.Client.Delete(t)
	checkError(err, c)
	c.JSON(200, res)
}

1.4 清空指定表的所有数据

HBase Shell 对应代码

truncate 'course'

没找到清空所有数据的hrpc函数，只能先拿到scanner再执行rowKey的每条删除。

如果是delete表操作需要先disable表，再删除表。

func TableTruncate(c *gin.Context) {
	table := c.Query("table")
	// ^ 下方注释代码是 Table Delete
	// 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)
	t2, err := hrpc.NewScan(context.Background(), []byte(table))
	checkError(err, c)
	res := variable.Client.Scan(t2)
	row, err := res.Next()
	for err != io.EOF && row != nil {
		t, err := hrpc.NewDelStr(context.Background(), table, string(row.Cells[0].Row), nil)
		checkError(err, c)
		_, err = variable.Client.Delete(t)
		checkError(err, c)
		row, err = res.Next()
	}
	c.JSON(200, gin.H{"result": "删除成功"})
}

1.5 统计表的行数

HBase Shell 对应代码

count 'course'

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)
}

localhost:1313/TableRowsCount?table=course 测试结果

3

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"})
}

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。

{
    "result": "创建成功"
}

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)
}

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)
}

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"
    }
]

localhost:1313/TableColumnScan?table=course&column=C_Credit:new

[
    {
        "row": "c001",
        "family": "C_Credit",
        "qualifier": "new",
        "timestamp": 1680434951646,
        "cell_type": 4,
        "value": "5.0"
    }
]

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)
}

{
    "Cells": null,
    "Stale": false,
    "Partial": false,
    "Exists": null
}

再次调用1.5函数接口，执行结果符合预期。

2

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。