Go - Gin URL shortener service using PostgreSQL

controller.go

package main

import (
  "net/http"
  "strings"
  "github.com/gin-gonic/gin"
)

type ShortenUrlRequestBody struct {
  SrcUrl string `json:"srcUrl"`
}

type ShortenUrlResponseBody struct {
  SrcUrl       string `json:"srcUrl"`
  ShortenedUrl string `json:"shortenedUrl"`
}

func HandleRequest(c *gin.Context) {
  var reqBody ShortenUrlRequestBody
  if err := c.BindJSON(&reqBody); err != nil {
    c.JSON(http.StatusBadRequest, gin.H{"error": "Request is not a valid JSON"})
    return
  }

  srcUrl := reqBody.SrcUrl
  if len(srcUrl) > 250 {
    c.JSON(http.StatusBadRequest, gin.H{"error": "Parameter 'srcUrl' must not be more than 250 characters"})
    return
  }

  if !(strings.HasPrefix(srcUrl, "http://") || strings.HasPrefix(srcUrl, "https://")) {
    c.JSON(http.StatusBadRequest, gin.H{"error": "Parameter 'srcUrl' must start with http:// or https://"})
    return
  }

  shortenedUrl := Shorten(srcUrl)
  if len(shortenedUrl) == 0 {
    c.JSON(http.StatusInternalServerError, gin.H{"error": "Failed to shorten"})
    return
  }

  rspBody := &ShortenUrlResponseBody{
    SrcUrl:       srcUrl,
    ShortenedUrl: shortenedUrl,
  }
  c.JSON(http.StatusOK, rspBody)
}

db.go

package main

import (
  "context"
  "database/sql"
  "os"
  "time"

  "github.com/uptrace/bun"
  "github.com/uptrace/bun/dialect/pgdialect"
  "github.com/uptrace/bun/driver/pgdriver"
)

type ShortenedUrl struct {
  bun.BaseModel `bun:"table:shortenedurls"`
  Id            string    `bun:"id,pk"`
  SrcUrl        string    `bun:"srcurl"`
  Created       time.Time `bun:"created"`
  LastAccessed  time.Time `bun:"lastaccessed"`
}

var sqldb = sql.OpenDB(pgdriver.NewConnector(
  pgdriver.WithNetwork("tcp"),
  pgdriver.WithAddr("localhost:5432"),
  pgdriver.WithUser(os.Getenv("dbUser")),
  pgdriver.WithPassword(os.Getenv("dbUserPass")),
  pgdriver.WithDatabase(os.Getenv("dbName")),
  pgdriver.WithInsecure(true),
))

var db = bun.NewDB(sqldb, pgdialect.New())

func init() {
  sqldb.SetMaxOpenConns(10)
  sqldb.SetMaxIdleConns(10)
}

func Save(id string, srcUrl string) bool {
  ctx := context.Background()
  shortenedUrl := &ShortenedUrl{
    Id:           id,
    SrcUrl:       srcUrl,
    Created:      time.Now(),
    LastAccessed: time.Now(),
  }
  _, err := db.NewInsert().Model(shortenedUrl).Exec(ctx)
  if err != nil {
    return false
  }
  return true
}

main.go

package main

import (
  "github.com/gin-gonic/gin"
)

func main() {
  r := gin.New()
  r.POST("/shorten", HandleRequest)
  r.Run(":3000")
}

service.go

package main

import gonanoid "github.com/matoous/go-nanoid/v2"

var baseUrl = "http://test.short/"

func Shorten(srcUrl string) string {
  id, _ := gonanoid.New(10)
  shortenedUrl := baseUrl + id
  Save(id, srcUrl)
  return shortenedUrl
}