url_shortiner/db.go
Arnas Udovic cf76bc052e abcex v3
2024-09-20 11:17:32 +03:00

145 lines
2.6 KiB
Go

package main
import (
"database/sql"
"fmt"
abcex "g.arns.lt/zordsdavini/abcex/v3"
_ "github.com/mattn/go-sqlite3"
)
var migrations = []string{}
func connectDB() (*sql.DB, error) {
db, err := sql.Open("sqlite3", "./main.db")
if err != nil {
return db, err
}
err = checkPreinstall(db)
if err != nil {
return db, err
}
return db, nil
}
func checkPreinstall(db *sql.DB) error {
sqlStmt := `
CREATE TABLE IF NOT EXISTS Urls (id INTEGER NOT NULL PRIMARY KEY, url TEXT NOT NULL, short_url TEXT NULL);
CREATE UNIQUE INDEX IF NOT EXISTS url_idx ON Urls (short_url);
CREATE TABLE IF NOT EXISTS Stats (id INTEGER NOT NULL PRIMARY KEY, name TEXT NOT NULL, count INT, comment TEXT);
CREATE UNIQUE INDEX IF NOT EXISTS stats_idx ON Stats (name);
INSERT OR IGNORE INTO Stats (name, count) VALUES ('last_migration', 0);
`
_, err := db.Exec(sqlStmt)
if err != nil {
return err
}
err = runMigrations(db)
if err != nil {
return err
}
return nil
}
func runMigrations(db *sql.DB) error {
lastMigration, err := getStatsCounter(db, "last_migration")
if err != nil {
return err
}
for i := lastMigration; i < len(migrations); i++ {
sqlStmt := migrations[i]
_, err := db.Exec(sqlStmt)
if err != nil {
return err
}
db.Exec("UPDATE Stats SET count=count+1 WHERE name='last_migration';")
}
return nil
}
func getStatsCounter(db *sql.DB, name string) (int, error) {
stmt, err := db.Prepare("SELECT count FROM Stats WHERE name = ?")
if err != nil {
return 0, err
}
defer stmt.Close()
var count int
err = stmt.QueryRow(name).Scan(&count)
if err != nil {
return 0, nil
}
return count, nil
}
func getStatsComment(db *sql.DB, name string) (string, error) {
stmt, err := db.Prepare("SELECT comment FROM Stats WHERE name = ?")
if err != nil {
return "", err
}
defer stmt.Close()
var comment string
err = stmt.QueryRow(name).Scan(&comment)
if err != nil {
return "", nil
}
return comment, nil
}
func getShortUrl(db *sql.DB, url string) string {
if len(url) == 0 {
return ""
}
fmt.Println(url)
res, err := db.Exec(
"INSERT INTO Urls (url) VALUES (?);",
url,
)
if err != nil {
return ""
}
lid, err := res.LastInsertId()
if err != nil {
return ""
}
shortUrl := abcex.Encode(lid)
fmt.Println(lid, shortUrl)
db.Exec(
"UPDATE Urls SET short_url=? WHERE id=?",
shortUrl,
lid,
)
return shortUrl
}
func getRedirectUrl(db *sql.DB, shortUrl string) string {
stmt, err := db.Prepare("SELECT url FROM Urls WHERE short_url = ?")
if err != nil {
return ""
}
defer stmt.Close()
var url string
err = stmt.QueryRow(shortUrl).Scan(&url)
if err != nil {
return ""
}
return url
}