Automatically load extensions. (#115)

Author: ncruces

conn.go

@@ -72,6 +72,9 @@ func newConn(filename string, flags OpenFlag) (conn *Conn, err error) {
 	c.arena = c.newArena(1024)
 	c.ctx = context.WithValue(c.ctx, connKey{}, c)
 	c.handle, err = c.openDB(filename, flags)
+	if err == nil {
+		err = initExtensions(c)
+	}
 	if err != nil {
 		return nil, err
 	}

ext/array/array.go

@@ -15,8 +15,8 @@ import (
 // The argument must be bound to a Go slice or array of
 // ints, floats, bools, strings or byte slices,
 // using [sqlite3.BindPointer] or [sqlite3.Pointer].
-func Register(db *sqlite3.Conn) {
-	sqlite3.CreateModule(db, "array", nil,
+func Register(db *sqlite3.Conn) error {
+	return sqlite3.CreateModule(db, "array", nil,
 		func(db *sqlite3.Conn, _, _, _ string, _ ...string) (array, error) {
 			err := db.DeclareVTab(`CREATE TABLE x(value, array HIDDEN)`)
 			return array{}, err

ext/array/array_test.go

@@ -15,10 +15,7 @@ import (
 )
 
 func Example_driver() {
-	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
-		array.Register(c)
-		return nil
-	})
+	db, err := driver.Open(":memory:", array.Register)
 	if err != nil {
 		log.Fatal(err)
 	}
@@ -53,14 +50,14 @@ func Example_driver() {
 }
 
 func Example() {
+	sqlite3.AutoExtension(array.Register)
+
 	db, err := sqlite3.Open(":memory:")
 	if err != nil {
 		log.Fatal(err)
 	}
 	defer db.Close()
 
-	array.Register(db)
-
 	stmt, _, err := db.Prepare(`
 		SELECT name
 		FROM pragma_function_list
@@ -91,10 +88,7 @@ func Example() {
 func Test_cursor_Column(t *testing.T) {
 	t.Parallel()
 
-	db, err := driver.Open(":memory:", func(c *sqlite3.Conn) error {
-		array.Register(c)
-		return nil
-	})
+	db, err := driver.Open(":memory:", array.Register)
 	if err != nil {
 		t.Fatal(err)
 	}
@@ -139,7 +133,10 @@ func Test_array_errors(t *testing.T) {
 	}
 	defer db.Close()
 
-	array.Register(db)
+	err = array.Register(db)
+	if err != nil {
+		t.Fatal(err)
+	}
 
 	err = db.Exec(`SELECT * FROM array()`)
 	if err == nil {

ext/blobio/blob.go

@@ -29,10 +29,11 @@ import (
 // along with the [sqlite3.Blob] handle.
 //
 // https://sqlite.org/c3ref/blob.html
-func Register(db *sqlite3.Conn) {
-	db.CreateFunction("readblob", 6, 0, readblob)
-	db.CreateFunction("writeblob", 6, 0, writeblob)
-	db.CreateFunction("openblob", -1, 0, openblob)
+func Register(db *sqlite3.Conn) error {
+	return errors.Join(
+		db.CreateFunction("readblob", 6, 0, readblob),
+		db.CreateFunction("writeblob", 6, 0, writeblob),
+		db.CreateFunction("openblob", -1, 0, openblob))
 }
 
 // OpenCallback is the type for the openblob callback.

ext/blobio/blob_test.go

@@ -18,10 +18,7 @@ import (
 
 func Example() {
 	// Open the database, registering the extension.
-	db, err := driver.Open("file:/test.db?vfs=memdb", func(conn *sqlite3.Conn) error {
-		blobio.Register(conn)
-		return nil
-	})
+	db, err := driver.Open("file:/test.db?vfs=memdb", blobio.Register)
 
 	if err != nil {
 		log.Fatal(err)
@@ -60,6 +57,11 @@ func Example() {
 	// Hello BLOB!
 }
 
+func init() {
+	sqlite3.AutoExtension(blobio.Register)
+	sqlite3.AutoExtension(array.Register)
+}
+
 func Test_readblob(t *testing.T) {
 	t.Parallel()
 
@@ -69,9 +71,6 @@ func Test_readblob(t *testing.T) {
 	}
 	defer db.Close()
 
-	blobio.Register(db)
-	array.Register(db)
-
 	err = db.Exec(`SELECT readblob()`)
 	if err == nil {
 		t.Fatal("want error")
@@ -129,9 +128,6 @@ func Test_openblob(t *testing.T) {
 	}
 	defer db.Close()
 
-	blobio.Register(db)
-	array.Register(db)
-
 	err = db.Exec(`SELECT openblob()`)
 	if err == nil {
 		t.Fatal("want error")

ext/bloom/bloom.go

@@ -20,8 +20,8 @@ import (
 // Register registers the bloom_filter virtual table:
 //
 //	CREATE VIRTUAL TABLE foo USING bloom_filter(nElements, falseProb, kHashes)
-func Register(db *sqlite3.Conn) {
-	sqlite3.CreateModule(db, "bloom_filter", create, connect)
+func Register(db *sqlite3.Conn) error {
+	return sqlite3.CreateModule(db, "bloom_filter", create, connect)
 }
 
 type bloom struct {

ext/bloom/bloom_test.go

@@ -12,6 +12,10 @@ import (
 	_ "github.com/ncruces/go-sqlite3/internal/testcfg"
 )
 
+func init() {
+	sqlite3.AutoExtension(bloom.Register)
+}
+
 func TestRegister(t *testing.T) {
 	t.Parallel()
 
@@ -21,8 +25,6 @@ func TestRegister(t *testing.T) {
 	}
 	defer db.Close()
 
-	bloom.Register(db)
-
 	err = db.Exec(`
 		CREATE VIRTUAL TABLE sports_cars USING bloom_filter(20);
 		INSERT INTO sports_cars VALUES ('ferrari'), ('lamborghini'), ('alfa romeo')
@@ -90,8 +92,6 @@ func Test_compatible(t *testing.T) {
 	}
 	defer db.Close()
 
-	bloom.Register(db)
-
 	query, _, err := db.Prepare(`SELECT COUNT(*) FROM plants(?)`)
 	if err != nil {
 		t.Fatal(err)

ext/csv/csv.go

@@ -23,13 +23,13 @@ import (
 
 // Register registers the CSV virtual table.
 // If a filename is specified, [os.Open] is used to open the file.
-func Register(db *sqlite3.Conn) {
-	RegisterFS(db, osutil.FS{})
+func Register(db *sqlite3.Conn) error {
+	return RegisterFS(db, osutil.FS{})
 }
 
 // RegisterFS registers the CSV virtual table.
 // If a filename is specified, fsys is used to open the file.
-func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
+func RegisterFS(db *sqlite3.Conn, fsys fs.FS) error {
 	declare := func(db *sqlite3.Conn, _, _, _ string, arg ...string) (_ *table, err error) {
 		var (
 			filename string
@@ -118,7 +118,7 @@ func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
 		return table, nil
 	}
 
-	sqlite3.CreateModule(db, "csv", declare, declare)
+	return sqlite3.CreateModule(db, "csv", declare, declare)
 }
 
 type table struct {

ext/csv/csv_test.go

@@ -18,7 +18,10 @@ func Example() {
 	}
 	defer db.Close()
 
-	csv.Register(db)
+	err = csv.Register(db)
+	if err != nil {
+		log.Fatal(err)
+	}
 
 	err = db.Exec(`
 		CREATE VIRTUAL TABLE eurofxref USING csv(
@@ -51,6 +54,10 @@ func Example() {
 	// On Twosday, 1€ = $1.1342
 }
 
+func init() {
+	sqlite3.AutoExtension(csv.Register)
+}
+
 func TestRegister(t *testing.T) {
 	t.Parallel()
 
@@ -60,8 +67,6 @@ func TestRegister(t *testing.T) {
 	}
 	defer db.Close()
 
-	csv.Register(db)
-
 	const data = `
 # Comment
 "Rob"	"Pike"	rob
@@ -124,8 +129,6 @@ func TestAffinity(t *testing.T) {
 	}
 	defer db.Close()
 
-	csv.Register(db)
-
 	const data = "01\n0.10\ne"
 	err = db.Exec(`
 		CREATE VIRTUAL TABLE temp.nums USING csv(
@@ -168,8 +171,6 @@ func TestRegister_errors(t *testing.T) {
 	}
 	defer db.Close()
 
-	csv.Register(db)
-
 	err = db.Exec(`CREATE VIRTUAL TABLE temp.users USING csv()`)
 	if err == nil {
 		t.Fatal("want error")

ext/fileio/fileio.go

@@ -14,24 +14,26 @@ import (
 
 // Register registers SQL functions readfile, writefile, lsmode,
 // and the table-valued function fsdir.
-func Register(db *sqlite3.Conn) {
-	RegisterFS(db, nil)
+func Register(db *sqlite3.Conn) error {
+	return RegisterFS(db, nil)
 }
 
 // Register registers SQL functions readfile, lsmode,
 // and the table-valued function fsdir;
 // fsys will be used to read files and list directories.
-func RegisterFS(db *sqlite3.Conn, fsys fs.FS) {
-	db.CreateFunction("lsmode", 1, sqlite3.DETERMINISTIC, lsmode)
-	db.CreateFunction("readfile", 1, sqlite3.DIRECTONLY, readfile(fsys))
+func RegisterFS(db *sqlite3.Conn, fsys fs.FS) error {
+	var err error
 	if fsys == nil {
-		db.CreateFunction("writefile", -1, sqlite3.DIRECTONLY, writefile)
+		err = db.CreateFunction("writefile", -1, sqlite3.DIRECTONLY, writefile)
 	}
-	sqlite3.CreateModule(db, "fsdir", nil, func(db *sqlite3.Conn, _, _, _ string, _ ...string) (fsdir, error) {
-		err := db.DeclareVTab(`CREATE TABLE x(name,mode,mtime TIMESTAMP,data,path HIDDEN,dir HIDDEN)`)
-		db.VTabConfig(sqlite3.VTAB_DIRECTONLY)
-		return fsdir{fsys}, err
-	})
+	return errors.Join(err,
+		db.CreateFunction("readfile", 1, sqlite3.DIRECTONLY, readfile(fsys)),
+		db.CreateFunction("lsmode", 1, sqlite3.DETERMINISTIC, lsmode),
+		sqlite3.CreateModule(db, "fsdir", nil, func(db *sqlite3.Conn, _, _, _ string, _ ...string) (fsdir, error) {
+			err := db.DeclareVTab(`CREATE TABLE x(name,mode,mtime TIMESTAMP,data,path HIDDEN,dir HIDDEN)`)
+			db.VTabConfig(sqlite3.VTAB_DIRECTONLY)
+			return fsdir{fsys}, err
+		}))
 }
 
 func lsmode(ctx sqlite3.Context, arg ...sqlite3.Value) {