go gin gorm连接postgres postgis输出geojson
1. 技术环境
go-gin-gorm
postgres-postgis
go vscode环境安装-智能提示配置
2. 简单实现代码
思路就是:采用原生sql实现查询、更新等,采用gorm的raw来执行sql语句
package mainimport ("fmt""net/http""github.com/gin-gonic/gin""gorm.io/driver/postgres""gorm.io/gorm"
)
// 前提是在postgres中安装好postgis插件
func main() {dsn := "host=localhost user=postgres password=5241 dbname=test port=5432 sslmode=disable TimeZone=Asia/Shanghai"db, _ := gorm.Open(postgres.New(postgres.Config{DSN: dsn,PreferSimpleProtocol: true,}), &gorm.Config{})r := gin.Default()r.GET("/data/:table_name", func(c *gin.Context) {table_name := c.Param("table_name")// 从postgis中利用 ST 函数 获得的结果,以string返回,然后前端进行解析即可var result stringif db.Migrator().HasTable(table_name) {sqls := fmt.Sprintf("select json_build_object('type', 'FeatureCollection', 'name', '%s', 'features', json_agg(ST_ASGeoJSON(t.*)::json)) from %s AS t", table_name, table_name)db.Raw(sqls).Scan(&result)}fmt.Printf("%q", result)c.JSON(http.StatusOK, gin.H{"message": "ok","data": result,})})r.Run(":8080")
}
3. 结果图片