CODEWITHSUNDEEP
mysqltemplatesgowebstruct
grethinam
grethinam

Reputation: 43

Display mysql table using template in Golang website

I am in the process learning GoLang web development, where I am trying a simple example of display a table in mysql database at Webpage rendered using Golang template. Below is the snippet of my code, which is not working.Table rendering is failing,where range function at template not working

Server.go

package main

import (
    "fmt"
    "net/http"
    _ "github.com/go-sql-driver/mysql"
    "database/sql"
    "os"
    "html/template"
)

type Employee struct {
    fname, sname, dname, email string
}

func helloWorld(w http.ResponseWriter, r *http.Request){
    name, err := os.Hostname()
    checkErr(err)
    fmt.Fprintf(w, "HOSTNAME : %s\n", name)
}

func dbConnect() (db *sql.DB) {
    dbDriver := "mysql"
    dbUser := "root"
    dbPass := "password"
    dbHost := "mysql.go"
    dbPort := "3306"
    dbName := "company"
    db, err := sql.Open(dbDriver, dbUser +":"+ dbPass +"@tcp("+ dbHost +":"+ dbPort +")/"+ dbName +"?charset=utf8")
    checkErr(err)
    return db
}

func dbSelect() []Employee{
    db := dbConnect()
    rows, err := db.Query("select * from employees")
    checkErr(err)

    employee := Employee{}
    employees := []Employee{}

    for rows.Next() {
        var first_name, last_name, department, email string
        err = rows.Scan(&first_name, &last_name, &department, &email)
        checkErr(err)
        employee.fname = first_name
        employee.sname = last_name
        employee.dname = department
        employee.email = email
        employees = append(employees, employee)

    }
    defer db.Close()
    return employees
}

var tmpl = template.Must(template.ParseFiles("layout.html"))
//var tmpl = template.Must(template.ParseGlob("layout.html"))
func dbTableHtml(w http.ResponseWriter, r *http.Request){
    table := dbSelect()
    tmpl.ExecuteTemplate(w, "Index", table)
}

func dbTable(w http.ResponseWriter, r *http.Request){
    table := dbSelect()
    for i := range(table) {
        emp := table[i]
        fmt.Fprintf(w,"YESS|%12s|%12s|%12s|%20s|\n" ,emp.fname ,emp.sname ,emp.dname ,emp.email)
    }
}

func main() {
    http.HandleFunc("/", helloWorld)
    http.HandleFunc("/view", dbTableHtml) 
    http.HandleFunc("/raw", dbTable)
    http.ListenAndServe(":8080", nil)
}

func checkErr(err error) {
    if err != nil {
        panic(err)
    }
}

layout.html

{{ define "Index" }}
<!DOCTYPE html>
<html lang="en-US">
    <head>
        <title>Maithanam Website</title>
        <meta charset="UTF-8" />
    </head>
    <body>
        <h1>Maithanammm website for mysql</h1> 

    {{ $length := len . }}
    <h3>Length {{$length}}</h3> 

    <table border="1">
      <tr>
        <td>FirstName</td>
        <td>SecondName</td>
        <td>Department</td>
        <td>Email</td>
      </tr>
    {{ range . }}
      <tr>
        <td>{{ .fname }}</td>
        <td> {{ .sname }} </td>
        <td>{{ .dname }} </td>
        <td>{{ .email }} </td>
      </tr>
    {{ end }}
    </table>

    </body>
</html>
{{ end }}

WebPage enter image description here

Upvotes: 3

Views: 3857

Answers (1)

mu is too short
mu is too short

Reputation: 434785

You have two problems:

  1. You're not checking for errors when you call ExecuteTemplate.
  2. Your template is using non-exported fields, taking care of your first problem would have told you this.

For the first problem:

err := tmpl.ExecuteTemplate(w, "Index", table)
if err != nil {
    // Do something with the error
}

For the second problem, change your struct to have exported fields:

type Employee struct {
    Fname, Sname, Dname, Email string
}

and then change your template to use the new field names.

Upvotes: 4

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