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|
//golangcitest:args -Esqlclosecheck
package testdata
import (
"context"
"database/sql"
"log"
"strings"
)
var (
ctx context.Context
db *sql.DB
age = 27
userID = 43
)
func rowsCorrectDeferBlock() {
rows, err := db.QueryContext(ctx, "SELECT name FROM users WHERE age=?", age)
if err != nil {
log.Fatal(err)
}
defer func() {
err := rows.Close()
if err != nil {
log.Print("problem closing rows")
}
}()
names := make([]string, 0)
for rows.Next() {
var name string
if err := rows.Scan(&name); err != nil {
log.Fatal(err)
}
names = append(names, name)
}
// Check for errors from iterating over rows.
if err := rows.Err(); err != nil {
log.Fatal(err)
}
log.Printf("%s are %d years old", strings.Join(names, ", "), age)
}
func rowsCorrectDefer() {
rows, err := db.QueryContext(ctx, "SELECT name FROM users WHERE age=?", age)
if err != nil {
log.Fatal(err)
}
defer rows.Close()
names := make([]string, 0)
for rows.Next() {
var name string
if err := rows.Scan(&name); err != nil {
log.Fatal(err)
}
names = append(names, name)
}
// Check for errors from iterating over rows.
if err := rows.Err(); err != nil {
log.Fatal(err)
}
log.Printf("%s are %d years old", strings.Join(names, ", "), age)
}
func rowsMissingClose() {
rows, err := db.QueryContext(ctx, "SELECT name FROM users WHERE age=?", age) // want "Rows/Stmt was not closed"
if err != nil {
log.Fatal(err)
}
// defer rows.Close()
names := make([]string, 0)
for rows.Next() {
var name string
if err := rows.Scan(&name); err != nil {
log.Fatal(err)
}
names = append(names, name)
}
// Check for errors from iterating over rows.
if err := rows.Err(); err != nil {
log.Fatal(err)
}
log.Printf("%s are %d years old", strings.Join(names, ", "), age)
}
func rowsNonDeferClose() {
rows, err := db.QueryContext(ctx, "SELECT name FROM users WHERE age=?", age)
if err != nil {
log.Fatal(err)
}
names := make([]string, 0)
for rows.Next() {
var name string
if err := rows.Scan(&name); err != nil {
log.Fatal(err)
}
names = append(names, name)
}
// Check for errors from iterating over rows.
if err := rows.Err(); err != nil {
log.Fatal(err)
}
log.Printf("%s are %d years old", strings.Join(names, ", "), age)
rows.Close() // want "Close should use defer"
}
func rowsPassedAndClosed() {
rows, err := db.QueryContext(ctx, "SELECT name FROM users")
if err != nil {
log.Fatal(err)
}
rowsClosedPassed(rows)
}
func rowsClosedPassed(rows *sql.Rows) {
rows.Close()
}
func rowsPassedAndNotClosed(rows *sql.Rows) {
rows, err := db.QueryContext(ctx, "SELECT name FROM users")
if err != nil {
log.Fatal(err)
}
rowsDontClosedPassed(rows)
}
func rowsDontClosedPassed(*sql.Rows) {
}
func rowsReturn() (*sql.Rows, error) {
rows, err := db.QueryContext(ctx, "SELECT name FROM users WHERE age=?", age)
if err != nil {
log.Fatal(err)
}
return rows, nil
}
func rowsReturnShort() (*sql.Rows, error) {
return db.QueryContext(ctx, "SELECT name FROM users WHERE age=?", age)
}
func stmtCorrectDeferBlock() {
// In normal use, create one Stmt when your process starts.
stmt, err := db.PrepareContext(ctx, "SELECT username FROM users WHERE id = ?")
if err != nil {
log.Fatal(err)
}
defer func() {
err := stmt.Close()
if err != nil {
log.Print("problem closing stmt")
}
}()
// Then reuse it each time you need to issue the query.
var username string
err = stmt.QueryRowContext(ctx, userID).Scan(&username)
switch {
case err == sql.ErrNoRows:
log.Fatalf("no user with id %d", userID)
case err != nil:
log.Fatal(err)
default:
log.Printf("username is %s\n", username)
}
}
func stmtCorrectDefer() {
// In normal use, create one Stmt when your process starts.
stmt, err := db.PrepareContext(ctx, "SELECT username FROM users WHERE id = ?")
if err != nil {
log.Fatal(err)
}
defer stmt.Close()
// Then reuse it each time you need to issue the query.
var username string
err = stmt.QueryRowContext(ctx, userID).Scan(&username)
switch {
case err == sql.ErrNoRows:
log.Fatalf("no user with id %d", userID)
case err != nil:
log.Fatal(err)
default:
log.Printf("username is %s\n", username)
}
}
func stmtMissingClose() {
// In normal use, create one Stmt when your process starts.
stmt, err := db.PrepareContext(ctx, "SELECT username FROM users WHERE id = ?") // want "Rows/Stmt was not closed"
if err != nil {
log.Fatal(err)
}
// defer stmt.Close()
// Then reuse it each time you need to issue the query.
var username string
err = stmt.QueryRowContext(ctx, userID).Scan(&username)
switch {
case err == sql.ErrNoRows:
log.Fatalf("no user with id %d", userID)
case err != nil:
log.Fatal(err)
default:
log.Printf("username is %s\n", username)
}
}
func stmtNonDeferClose() {
// In normal use, create one Stmt when your process starts.
stmt, err := db.PrepareContext(ctx, "SELECT username FROM users WHERE id = ?")
if err != nil {
log.Fatal(err)
}
// Then reuse it each time you need to issue the query.
var username string
err = stmt.QueryRowContext(ctx, userID).Scan(&username)
switch {
case err == sql.ErrNoRows:
log.Fatalf("no user with id %d", userID)
case err != nil:
log.Fatal(err)
default:
log.Printf("username is %s\n", username)
}
stmt.Close() // want "Close should use defer"
}
func stmtReturn() (*sql.Stmt, error) {
stmt, err := db.PrepareContext(ctx, "SELECT username FROM users WHERE id = ?")
if err != nil {
return nil, err
}
return stmt, nil
}
func stmtReturnShort() (*sql.Stmt, error) {
return db.PrepareContext(ctx, "SELECT username FROM users WHERE id = ?")
}
|
