Initial attempt at supporting Go 1.8's context in database/sql

named_context.go

@@ -0,0 +1,110 @@
+// +build go1.8
+
+package sqlx
+
+import (
+	"context"
+	"database/sql"
+)
+
+// A union interface of contextPreparer and binder, required to be able to
+// prepare named statements with context (as the bindtype must be determined).
+type namedPreparerContext interface {
+	PreparerContext
+	binder
+}
+
+func prepareNamedContext(ctx context.Context, p namedPreparerContext, query string) (*NamedStmt, error) {
+	bindType := BindType(p.DriverName())
+	q, args, err := compileNamedQuery([]byte(query), bindType)
+	if err != nil {
+		return nil, err
+	}
+	stmt, err := PreparexContext(ctx, p, q)
+	if err != nil {
+		return nil, err
+	}
+	return &NamedStmt{
+		QueryString: q,
+		Params:      args,
+		Stmt:        stmt,
+	}, nil
+}
+
+// ExecContext executes a named statement using the struct passed.
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) ExecContext(ctx context.Context, arg interface{}) (sql.Result, error) {
+	args, err := bindAnyArgs(n.Params, arg, n.Stmt.Mapper)
+	if err != nil {
+		return *new(sql.Result), err
+	}
+	return n.Stmt.ExecContext(ctx, args...)
+}
+
+// QueryContext executes a named statement using the struct argument, returning rows.
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) QueryContext(ctx context.Context, arg interface{}) (*sql.Rows, error) {
+	args, err := bindAnyArgs(n.Params, arg, n.Stmt.Mapper)
+	if err != nil {
+		return nil, err
+	}
+	return n.Stmt.QueryContext(ctx, args...)
+}
+
+// QueryRowContext executes a named statement against the database.  Because sqlx cannot
+// create a *sql.Row with an error condition pre-set for binding errors, sqlx
+// returns a *sqlx.Row instead.
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) QueryRowContext(ctx context.Context, arg interface{}) *Row {
+	args, err := bindAnyArgs(n.Params, arg, n.Stmt.Mapper)
+	if err != nil {
+		return &Row{err: err}
+	}
+	return n.Stmt.QueryRowxContext(ctx, args...)
+}
+
+// MustExecContext execs a NamedStmt, panicing on error
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) MustExecContext(ctx context.Context, arg interface{}) sql.Result {
+	res, err := n.ExecContext(ctx, arg)
+	if err != nil {
+		panic(err)
+	}
+	return res
+}
+
+// QueryxContext using this NamedStmt
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) QueryxContext(ctx context.Context, arg interface{}) (*Rows, error) {
+	r, err := n.QueryContext(ctx, arg)
+	if err != nil {
+		return nil, err
+	}
+	return &Rows{Rows: r, Mapper: n.Stmt.Mapper, unsafe: isUnsafe(n)}, err
+}
+
+// QueryRowxContext this NamedStmt.  Because of limitations with QueryRow, this is
+// an alias for QueryRow.
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) QueryRowxContext(ctx context.Context, arg interface{}) *Row {
+	return n.QueryRowContext(ctx, arg)
+}
+
+// SelectContext using this NamedStmt
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) SelectContext(ctx context.Context, dest interface{}, arg interface{}) error {
+	rows, err := n.QueryxContext(ctx, arg)
+	if err != nil {
+		return err
+	}
+	// if something happens here, we want to make sure the rows are Closed
+	defer rows.Close()
+	return scanAll(rows, dest, false)
+}
+
+// GetContext using this NamedStmt
+// Any named placeholder parameters are replaced with fields from arg.
+func (n *NamedStmt) GetContext(ctx context.Context, dest interface{}, arg interface{}) error {
+	r := n.QueryRowxContext(ctx, arg)
+	return r.scanAny(dest, false)
+}

sqlx_context.go

@@ -0,0 +1,250 @@
+// +build go1.8
+
+package sqlx
+
+import (
+	"context"
+	"database/sql"
+	"fmt"
+	"io/ioutil"
+	"path/filepath"
+	"reflect"
+)
+
+// QueryerContext is an interface used by GetContext and SelectContext
+type QueryerContext interface {
+	QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error)
+	QueryxContext(ctx context.Context, query string, args ...interface{}) (*Rows, error)
+	QueryRowxContext(ctx context.Context, query string, args ...interface{}) *Row
+}
+
+// PreparerContext is an interface used by PreparexContext.
+type PreparerContext interface {
+	PrepareContext(ctx context.Context, query string) (*sql.Stmt, error)
+}
+
+// ExecerContext is an interface used by MustExecContext and LoadFileContext
+type ExecerContext interface {
+	ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error)
+}
+
+// SelectContext executes a query using the provided Queryer, and StructScans
+// each row into dest, which must be a slice.  If the slice elements are
+// scannable, then the result set must have only one column.  Otherwise,
+// StructScan is used. The *sql.Rows are closed automatically.
+// Any placeholder parameters are replaced with supplied args.
+func SelectContext(ctx context.Context, q QueryerContext, dest interface{}, query string, args ...interface{}) error {
+	rows, err := q.QueryxContext(ctx, query, args...)
+	if err != nil {
+		return err
+	}
+	// if something happens here, we want to make sure the rows are Closed
+	defer rows.Close()
+	return scanAll(rows, dest, false)
+}
+
+// PreparexContext prepares a statement.
+//
+// The provided context is used for the preparation of the statement, not for
+// the execution of the statement.
+func PreparexContext(ctx context.Context, p PreparerContext, query string) (*Stmt, error) {
+	s, err := p.PrepareContext(ctx, query)
+	if err != nil {
+		return nil, err
+	}
+	return &Stmt{Stmt: s, unsafe: isUnsafe(p), Mapper: mapperFor(p)}, err
+}
+
+// GetContext does a QueryRow using the provided Queryer, and scans the
+// resulting row to dest.  If dest is scannable, the result must only have one
+// column. Otherwise, StructScan is used.  Get will return sql.ErrNoRows like
+// row.Scan would. Any placeholder parameters are replaced with supplied args.
+// An error is returned if the result set is empty.
+func GetContext(ctx context.Context, q QueryerContext, dest interface{}, query string, args ...interface{}) error {
+	r := q.QueryRowxContext(ctx, query, args...)
+	return r.scanAny(dest, false)
+}
+
+// LoadFileContext exec's every statement in a file (as a single call to Exec).
+// LoadFileContext may return a nil *sql.Result if errors are encountered
+// locating or reading the file at path.  LoadFile reads the entire file into
+// memory, so it is not suitable for loading large data dumps, but can be useful
+// for initializing schemas or loading indexes.
+//
+// FIXME: this does not really work with multi-statement files for mattn/go-sqlite3
+// or the go-mysql-driver/mysql drivers;  pq seems to be an exception here.  Detecting
+// this by requiring something with DriverName() and then attempting to split the
+// queries will be difficult to get right, and its current driver-specific behavior
+// is deemed at least not complex in its incorrectness.
+func LoadFileContext(ctx context.Context, e ExecerContext, path string) (*sql.Result, error) {
+	realpath, err := filepath.Abs(path)
+	if err != nil {
+		return nil, err
+	}
+	contents, err := ioutil.ReadFile(realpath)
+	if err != nil {
+		return nil, err
+	}
+	res, err := e.ExecContext(ctx, string(contents))
+	return &res, err
+}
+
+// MustExecContext execs the query using e and panics if there was an error.
+// Any placeholder parameters are replaced with supplied args.
+func MustExecContext(ctx context.Context, e ExecerContext, query string, args ...interface{}) sql.Result {
+	res, err := e.ExecContext(ctx, query, args...)
+	if err != nil {
+		panic(err)
+	}
+	return res
+}
+
+// PrepareNamedContext returns an sqlx.NamedStmt
+func (db *DB) PrepareNamedContext(ctx context.Context, query string) (*NamedStmt, error) {
+	return prepareNamedContext(ctx, db, query)
+}
+
+// SelectContext using this DB.
+// Any placeholder parameters are replaced with supplied args.
+func (db *DB) SelectContext(ctx context.Context, dest interface{}, query string, args ...interface{}) error {
+	return SelectContext(ctx, db, dest, query, args...)
+}
+
+// PreparexContext returns an sqlx.Stmt instead of a sql.Stmt.
+//
+// The provided context is used for the preparation of the statement, not for
+// the execution of the statement.
+func (db *DB) PreparexContext(ctx context.Context, query string) (*Stmt, error) {
+	return PreparexContext(ctx, db, query)
+}
+
+// QueryxContext queries the database and returns an *sqlx.Rows.
+// Any placeholder parameters are replaced with supplied args.
+func (db *DB) QueryxContext(ctx context.Context, query string, args ...interface{}) (*Rows, error) {
+	r, err := db.DB.QueryContext(ctx, query, args...)
+	if err != nil {
+		return nil, err
+	}
+	return &Rows{Rows: r, unsafe: db.unsafe, Mapper: db.Mapper}, err
+}
+
+// QueryRowxContext queries the database and returns an *sqlx.Row.
+// Any placeholder parameters are replaced with supplied args.
+func (db *DB) QueryRowxContext(ctx context.Context, query string, args ...interface{}) *Row {
+	rows, err := db.DB.QueryContext(ctx, query, args...)
+	return &Row{rows: rows, err: err, unsafe: db.unsafe, Mapper: db.Mapper}
+}
+
+// MustBeginTx starts a transaction, and panics on error.  Returns an *sqlx.Tx instead
+// of an *sql.Tx.
+//
+// The provided context is used until the transaction is committed or rolled
+// back. If the context is canceled, the sql package will roll back the
+// transaction. Tx.Commit will return an error if the context provided to
+// MustBeginContext is canceled.
+func (db *DB) MustBeginTx(ctx context.Context, opts *sql.TxOptions) *Tx {
+	tx, err := db.BeginTxx(ctx, opts)
+	if err != nil {
+		panic(err)
+	}
+	return tx
+}
+
+// BeginTxx begins a transaction and returns an *sqlx.Tx instead of an
+// *sql.Tx.
+//
+// The provided context is used until the transaction is committed or rolled
+// back. If the context is canceled, the sql package will roll back the
+// transaction. Tx.Commit will return an error if the context provided to
+// BeginxContext is canceled.
+func (db *DB) BeginTxx(ctx context.Context, opts *sql.TxOptions) (*Tx, error) {
+	tx, err := db.DB.BeginTx(ctx, opts)
+	if err != nil {
+		return nil, err
+	}
+	return &Tx{Tx: tx, driverName: db.driverName, unsafe: db.unsafe, Mapper: db.Mapper}, err
+}
+
+// StmtxContext returns a version of the prepared statement which runs within a
+// transaction. Provided stmt can be either *sql.Stmt or *sqlx.Stmt.
+func (tx *Tx) StmtxContext(ctx context.Context, stmt interface{}) *Stmt {
+	var s *sql.Stmt
+	switch v := stmt.(type) {
+	case Stmt:
+		s = v.Stmt
+	case *Stmt:
+		s = v.Stmt
+	case sql.Stmt:
+		s = &v
+	case *sql.Stmt:
+		s = v
+	default:
+		panic(fmt.Sprintf("non-statement type %v passed to Stmtx", reflect.ValueOf(stmt).Type()))
+	}
+	return &Stmt{Stmt: tx.StmtContext(ctx, s), Mapper: tx.Mapper}
+}
+
+// NamedStmtContext returns a version of the prepared statement which runs
+// within a transaction.
+func (tx *Tx) NamedStmtContext(ctx context.Context, stmt *NamedStmt) *NamedStmt {
+	return &NamedStmt{
+		QueryString: stmt.QueryString,
+		Params:      stmt.Params,
+		Stmt:        tx.StmtxContext(ctx, stmt.Stmt),
+	}
+}
+
+// SelectContext using the prepared statement.
+// Any placeholder parameters are replaced with supplied args.
+func (s *Stmt) SelectContext(ctx context.Context, dest interface{}, args ...interface{}) error {
+	return SelectContext(ctx, &qStmt{s}, dest, "", args...)
+}
+
+// GetContext using the prepared statement.
+// Any placeholder parameters are replaced with supplied args.
+// An error is returned if the result set is empty.
+func (s *Stmt) GetContext(ctx context.Context, dest interface{}, args ...interface{}) error {
+	return GetContext(ctx, &qStmt{s}, dest, "", args...)
+}
+
+// MustExecContext (panic) using this statement.  Note that the query portion of
+// the error output will be blank, as Stmt does not expose its query.
+// Any placeholder parameters are replaced with supplied args.
+func (s *Stmt) MustExecContext(ctx context.Context, args ...interface{}) sql.Result {
+	return MustExecContext(ctx, &qStmt{s}, "", args...)
+}
+
+// QueryRowxContext using this statement.
+// Any placeholder parameters are replaced with supplied args.
+func (s *Stmt) QueryRowxContext(ctx context.Context, args ...interface{}) *Row {
+	qs := &qStmt{s}
+	return qs.QueryRowxContext(ctx, "", args...)
+}
+
+// QueryxContext using this statement.
+// Any placeholder parameters are replaced with supplied args.
+func (s *Stmt) QueryxContext(ctx context.Context, args ...interface{}) (*Rows, error) {
+	qs := &qStmt{s}
+	return qs.QueryxContext(ctx, "", args...)
+}
+
+func (q *qStmt) QueryContext(ctx context.Context, query string, args ...interface{}) (*sql.Rows, error) {
+	return q.Stmt.QueryContext(ctx, args...)
+}
+
+func (q *qStmt) QueryxContext(ctx context.Context, query string, args ...interface{}) (*Rows, error) {
+	r, err := q.Stmt.QueryContext(ctx, args...)
+	if err != nil {
+		return nil, err
+	}
+	return &Rows{Rows: r, unsafe: q.Stmt.unsafe, Mapper: q.Stmt.Mapper}, err
+}
+
+func (q *qStmt) QueryRowxContext(ctx context.Context, query string, args ...interface{}) *Row {
+	rows, err := q.Stmt.QueryContext(ctx, args...)
+	return &Row{rows: rows, err: err, unsafe: q.Stmt.unsafe, Mapper: q.Stmt.Mapper}
+}
+
+func (q *qStmt) ExecContext(ctx context.Context, query string, args ...interface{}) (sql.Result, error) {
+	return q.Stmt.ExecContext(ctx, args...)
+}