I've been working on an API for authentication, and while trying to deploy it on a server I stumbled upon this odd bug. The code works perfectly fine on my laptop, but as soon as I try to deploy it, this error occurs:
PANIC: runtime error: invalid memory address or nil pointer dereference
goroutine 21 [running]:
github.com/urfave/negroni.(*Recovery).ServeHTTP.func1(0x7f5771b811e8, 0xc4200980e8, 0xc42009a870, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/recovery.go:159 +0xef
panic(0x84ad60, 0xcc4f30)
/usr/local/go/src/runtime/panic.go:502 +0x229
database/sql.(*Rows).close(0x0, 0x0, 0x0, 0x0, 0x0)
/usr/local/go/src/database/sql/sql.go:2907 +0x6b
database/sql.(*Rows).Close(0x0, 0x0, 0x0)
/usr/local/go/src/database/sql/sql.go:2903 +0x33
panic(0x8408e0, 0xc42008ab70)
/usr/local/go/src/runtime/panic.go:502 +0x229
github.com/lars250698/iotmap/api/models.PassQuery(0xc420096d38, 0x4, 0xc4201129a0, 0x0)
/home/linux/go/src/github.com/lars250698/iotmap/api/models/user.go:35 +0x236
github.com/lars250698/iotmap/api/controllers.Auth(0x7f5771b811e8, 0xc4200980e8, 0xc420138b00)
/home/linux/go/src/github.com/lars250698/iotmap/api/controllers/auth.go:28 +0x151
net/http.HandlerFunc.ServeHTTP(0x8d1d60, 0x7f5771b811e8, 0xc4200980e8, 0xc420138b00)
/usr/local/go/src/net/http/server.go:1947 +0x44
github.com/gorilla/mux.(*Router).ServeHTTP(0xc42013e850, 0x7f5771b811e8, 0xc4200980e8, 0xc420138b00)
/home/linux/go/src/github.com/gorilla/mux/mux.go:162 +0xed
github.com/gorilla/handlers.(*cors).ServeHTTP(0xc42014a480, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/gorilla/handlers/cors.go:52 +0xa3b
github.com/urfave/negroni.Wrap.func1(0x7f5771b811e8, 0xc4200980e8, 0xc420138800, 0xc420112980)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:46 +0x4d
github.com/urfave/negroni.HandlerFunc.ServeHTTP(0xc420112800, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800, 0xc420112980)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:29 +0x4e
github.com/urfave/negroni.middleware.ServeHTTP(0x9019c0, 0xc420112800, 0xc420112880, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0xa5
github.com/urfave/negroni.(middleware).ServeHTTP-fm(0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0x60
github.com/urfave/negroni.(*Static).ServeHTTP(0xc42008ff20, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800, 0xc420112960)
/home/linux/go/src/github.com/urfave/negroni/static.go:34 +0x8c
github.com/urfave/negroni.middleware.ServeHTTP(0x900e00, 0xc42008ff20, 0xc420112860, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0xa5
github.com/urfave/negroni.(middleware).ServeHTTP-fm(0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0x60
github.com/urfave/negroni.(*Logger).ServeHTTP(0xc42008f9b0, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800, 0xc420112940)
/home/linux/go/src/github.com/urfave/negroni/logger.go:62 +0x8e
github.com/urfave/negroni.middleware.ServeHTTP(0x900da0, 0xc42008f9b0, 0xc420112840, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0xa5
github.com/urfave/negroni.(middleware).ServeHTTP-fm(0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0x60
github.com/urfave/negroni.(*Recovery).ServeHTTP(0xc42009a870, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800, 0xc420112920)
/home/linux/go/src/github.com/urfave/negroni/recovery.go:193 +0x8c
github.com/urfave/negroni.middleware.ServeHTTP(0x900de0, 0xc42009a870, 0xc420112820, 0x7f5771b811e8, 0xc4200980e8, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:38 +0xa5
github.com/urfave/negroni.(*Negroni).ServeHTTP(0xc42008ff80, 0x904660, 0xc42012e1c0, 0xc420138800)
/home/linux/go/src/github.com/urfave/negroni/negroni.go:96 +0xf2
net/http.serverHandler.ServeHTTP(0xc420091040, 0x904660, 0xc42012e1c0, 0xc420138800)
/usr/local/go/src/net/http/server.go:2694 +0xbc
net/http.(*conn).serve(0xc4200a74a0, 0x9049a0, 0xc42009c500)
/usr/local/go/src/net/http/server.go:1830 +0x651
created by net/http.(*Server).Serve
/usr/local/go/src/net/http/server.go:2795 +0x27b
My code:
package models
import (
"database/sql"
_ "github.com/mattn/go-sqlite3"
)
type User struct {
Id int `json:"id"`
User string `json:"user"`
Admin bool `json:"admin"`
}
func PrepareSqlite() (db *sql.DB, err error) {
db, err = sql.Open("sqlite3","./auth.db")
if err != nil {
panic(err)
return
}
defer db.Close()
// My other Laptop fails here
statement, _ := db.Prepare("CREATE TABLE IF NOT EXISTS users (id INTEGER PRIMARY KEY, username TEXT, passw TEXT, admin INTEGER)")
statement.Exec()
return db, nil
}
func PassQuery(username string) (pass string) {
db, err := PrepareSqlite()
if err != nil {
panic(err)
return
}
// Server fails here
rows, err := db.Query("SELECT passw FROM users WHERE username=\"" + username + "\"")
defer rows.Close()
if err != nil {
panic(err)
return
}
for rows.Next() {
rows.Scan(&pass)
}
return pass
}
Anyone got any idea why this might happen? My machine is running Arch, the server is on Debian. I've already tried using several other gosqlite-drivers. On yet another machine, a similar error occurs, but the stacktrace shows that it occurs in the PrepareSqlite() method when calling db.Prepare(...). By this point I have no idea what this might be.
Edit: I've tried removing defer rows.Close(), which gave me the Error "Database is closed". After that, I've tried opening the database directly in the PassQuery() method, which gave me the first error once again. I suspect it might be something with opening the database, but I'm not sure what.
