qb: update, delete and performance improvements

qb/delete.go

@@ -0,0 +1,93 @@
+package qb
+
+// DELETE reference:
+// http://docs.datastax.com/en/dse/5.1/cql/cql/cql_reference/cql_commands/cqlDelete.html
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+	"time"
+)
+
+type DeleteBuilder struct {
+	table   string
+	columns columns
+	using   using
+	where   where
+	_if     _if
+	exists  bool
+}
+
+// Delete returns a new DeleteBuilder with the given table name.
+func Delete(table string) *DeleteBuilder {
+	return &DeleteBuilder{
+		table: table,
+	}
+}
+
+func (b *DeleteBuilder) ToCql() (stmt string, names []string, err error) {
+	if b.table == "" {
+		err = errors.New("delete statements must specify a table")
+		return
+	}
+	if len(b.where) == 0 {
+		err = fmt.Errorf("delete statements must have at least one WHERE clause")
+		return
+	}
+
+	cql := bytes.Buffer{}
+
+	cql.WriteString("DELETE ")
+	if len(b.columns) > 0 {
+		b.columns.writeCql(&cql)
+		cql.WriteByte(' ')
+	}
+	cql.WriteString("FROM ")
+	cql.WriteString(b.table)
+	cql.WriteByte(' ')
+
+	b.using.writeCql(&cql)
+
+	names = append(names, b.where.writeCql(&cql)...)
+	names = append(names, b._if.writeCql(&cql)...)
+
+	if b.exists {
+		cql.WriteString("IF EXISTS ")
+	}
+
+	stmt = cql.String()
+	return
+}
+
+// From sets the table to be deleted from.
+func (b *DeleteBuilder) From(table string) *DeleteBuilder {
+	b.table = table
+	return b
+}
+
+// Columns adds delete columns to the query.
+func (b *DeleteBuilder) Columns(columns ...string) *DeleteBuilder {
+	b.columns = append(b.columns, columns...)
+	return b
+}
+
+func (b *DeleteBuilder) Timestamp(t time.Time) *DeleteBuilder {
+	b.using.timestamp = t
+	return b
+}
+
+func (b *DeleteBuilder) Where(e ...expr) *DeleteBuilder {
+	b.where = append(b.where, e...)
+	return b
+}
+
+func (b *DeleteBuilder) If(e ...expr) *DeleteBuilder {
+	b._if = append(b._if, e...)
+	return b
+}
+
+func (b *DeleteBuilder) Existing() *DeleteBuilder {
+	b.exists = true
+	return b
+}

qb/delete_test.go

@@ -0,0 +1,100 @@
+package qb
+
+import (
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestDeleteBuilder(t *testing.T) {
+	m := mockExpr{
+		cql:   "expr",
+		names: []string{"expr"},
+	}
+
+	table := []struct {
+		B *DeleteBuilder
+		N []string
+		S string
+	}{
+		// Basic test for delete
+		{
+			B: Delete("cycling.cyclist_name").Where(m),
+			S: "DELETE FROM cycling.cyclist_name WHERE expr ",
+			N: []string{"expr"},
+		},
+		// Change table name
+		{
+			B: Delete("cycling.cyclist_name").Where(m).From("Foobar"),
+			S: "DELETE FROM Foobar WHERE expr ",
+			N: []string{"expr"},
+		},
+		// Add column
+		{
+			B: Delete("cycling.cyclist_name").Where(m).Columns("stars"),
+			S: "DELETE stars FROM cycling.cyclist_name WHERE expr ",
+			N: []string{"expr"},
+		},
+		// Add WHERE
+		{
+			B: Delete("cycling.cyclist_name").Where(m).Where(mockExpr{
+				cql:   "expr_1",
+				names: []string{"expr_1"},
+			}, mockExpr{
+				cql:   "expr_2",
+				names: []string{"expr_2"},
+			}),
+			S: "DELETE FROM cycling.cyclist_name WHERE expr AND expr_1 AND expr_2 ",
+			N: []string{"expr", "expr_1", "expr_2"},
+		},
+		// Add IF
+		{
+			B: Delete("cycling.cyclist_name").Where(m).If(mockExpr{
+				cql:   "expr_1",
+				names: []string{"expr_1"},
+			}, mockExpr{
+				cql:   "expr_2",
+				names: []string{"expr_2"},
+			}),
+			S: "DELETE FROM cycling.cyclist_name WHERE expr IF expr_1 AND expr_2 ",
+			N: []string{"expr", "expr_1", "expr_2"},
+		},
+		// Add TIMESTAMP
+		{
+			B: Delete("cycling.cyclist_name").Where(m).Timestamp(time.Unix(0, 0).Add(time.Microsecond * 123456789)),
+			S: "DELETE FROM cycling.cyclist_name USING TIMESTAMP 123456789 WHERE expr ",
+			N: []string{"expr"},
+		},
+		// Add IF EXISTS
+		{
+			B: Delete("cycling.cyclist_name").Where(m).Existing(),
+			S: "DELETE FROM cycling.cyclist_name WHERE expr IF EXISTS ",
+			N: []string{"expr"},
+		},
+	}
+
+	for _, test := range table {
+		stmt, names, err := test.B.ToCql()
+		if err != nil {
+			t.Error("unexpected error", err)
+		}
+		if diff := cmp.Diff(test.S, stmt); diff != "" {
+			t.Error(diff)
+		}
+		if diff := cmp.Diff(test.N, names); diff != "" {
+			t.Error(diff)
+		}
+	}
+}
+
+func BenchmarkDeleteBuilder(b *testing.B) {
+	m := mockExpr{
+		cql:   "expr",
+		names: []string{"expr"},
+	}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Delete("cycling.cyclist_name").Columns("id", "user_uuid", "firstname", "stars").Where(m)
+	}
+}

qb/expr.go

@@ -13,12 +13,24 @@ type expr interface {
 	WriteCql(cql *bytes.Buffer) (names []string)
 }
 
+type columns []string
+
+func (cols columns) writeCql(cql *bytes.Buffer) (names []string) {
+	for i, c := range cols {
+		cql.WriteString(c)
+		if i < len(cols)-1 {
+			cql.WriteByte(',')
+		}
+	}
+	return
+}
+
 type using struct {
 	timestamp time.Time
 	ttl       time.Duration
 }
 
-func (u using) WriteCql(cql *bytes.Buffer) (names []string) {
+func (u using) writeCql(cql *bytes.Buffer) (names []string) {
 	var v []string
 	if !u.timestamp.IsZero() {
 		v = append(v, fmt.Sprint("TIMESTAMP ", u.timestamp.UnixNano()/1000))
@@ -29,8 +41,41 @@ func (u using) WriteCql(cql *bytes.Buffer) (names []string) {
 	if len(v) > 0 {
 		cql.WriteString("USING ")
 		cql.WriteString(strings.Join(v, ","))
-		cql.WriteString(" ")
+		cql.WriteByte(' ')
 	}
 
 	return
 }
+
+type where []expr
+
+func (w where) writeCql(cql *bytes.Buffer) (names []string) {
+	if len(w) == 0 {
+		return
+	}
+
+	cql.WriteString("WHERE ")
+	return writeCql(w, cql)
+}
+
+type _if []expr
+
+func (w _if) writeCql(cql *bytes.Buffer) (names []string) {
+	if len(w) == 0 {
+		return
+	}
+
+	cql.WriteString("IF ")
+	return writeCql(w, cql)
+}
+
+func writeCql(es []expr, cql *bytes.Buffer) (names []string) {
+	for i, c := range es {
+		names = append(names, c.WriteCql(cql)...)
+		if i < len(es)-1 {
+			cql.WriteString(" AND ")
+		}
+	}
+	cql.WriteByte(' ')
+	return
+}

qb/insert.go

@@ -6,13 +6,12 @@ package qb
 import (
 	"bytes"
 	"errors"
-	"strings"
 	"time"
 )
 
 type InsertBuilder struct {
 	table   string
-	columns []string
+	columns columns
 	unique  bool
 	using   using
 }
@@ -41,17 +40,17 @@ func (b *InsertBuilder) ToCql() (stmt string, names []string, err error) {
 
 	cql.WriteString("INTO ")
 	cql.WriteString(b.table)
-	cql.WriteString(" ")
+	cql.WriteByte(' ')
 
-	cql.WriteString("(")
-	cql.WriteString(strings.Join(b.columns, ","))
+	cql.WriteByte('(')
+	b.columns.writeCql(&cql)
 	cql.WriteString(") ")
 
 	cql.WriteString("VALUES (")
-	cql.WriteString(placeholders(len(b.columns)))
+	placeholders(&cql, len(b.columns))
 	cql.WriteString(") ")
 
-	b.using.WriteCql(&cql)
+	b.using.writeCql(&cql)
 
 	if b.unique {
 		cql.WriteString("IF NOT EXISTS ")

qb/insert_test.go

@@ -69,6 +69,6 @@ func TestInsertBuilder(t *testing.T) {
 func BenchmarkInsertBuilder(b *testing.B) {
 	b.ResetTimer()
 	for i := 0; i < b.N; i++ {
-		Insert("foo").Columns("name", "age", "first", "last").ToCql()
+		Insert("cycling.cyclist_name").Columns("id", "user_uuid", "firstname", "stars")
 	}
 }

qb/mock.go

@@ -0,0 +1,14 @@
+package qb
+
+import "bytes"
+
+type mockExpr struct {
+	cql   string
+	names []string
+}
+
+func (m mockExpr) WriteCql(cql *bytes.Buffer) (names []string) {
+	cql.WriteString(m.cql)
+	names = m.names
+	return
+}

qb/qb.go

@@ -1,14 +1,18 @@
 package qb
 
 import (
-	"strings"
+	"bytes"
 )
 
 // placeholders returns a string with count ? placeholders joined with commas.
-func placeholders(count int) string {
+func placeholders(cql *bytes.Buffer, count int) {
 	if count < 1 {
-		return ""
+		return
 	}
 
-	return strings.Repeat(",?", count)[1:]
+	for i := 0; i < count-1; i++ {
+		cql.WriteByte('?')
+		cql.WriteByte(',')
+	}
+	cql.WriteByte('?')
 }

qb/update.go

@@ -0,0 +1,110 @@
+package qb
+
+import (
+	"bytes"
+	"errors"
+	"fmt"
+)
+
+// UPDATE reference:
+// http://docs.datastax.com/en/dse/5.1/cql/cql/cql_reference/cql_commands/cqlUpdate.html
+
+import (
+	"time"
+)
+
+type UpdateBuilder struct {
+	table   string
+	using   using
+	columns columns
+	where   where
+	_if     _if
+	exists  bool
+}
+
+// Update returns a new UpdateBuilder with the given table name.
+func Update(table string) *UpdateBuilder {
+	return &UpdateBuilder{
+		table: table,
+	}
+}
+
+func (b *UpdateBuilder) ToCql() (stmt string, names []string, err error) {
+	if b.table == "" {
+		err = errors.New("update statements must specify a table")
+		return
+	}
+	if len(b.columns) == 0 {
+		err = fmt.Errorf("update statements must have at least one SET clause")
+		return
+	}
+	if len(b.where) == 0 {
+		err = fmt.Errorf("update statements must have at least one WHERE clause")
+		return
+	}
+
+	cql := bytes.Buffer{}
+
+	cql.WriteString("UPDATE ")
+	cql.WriteString(b.table)
+	cql.WriteByte(' ')
+
+	b.using.writeCql(&cql)
+
+	cql.WriteString("SET ")
+	for i, c := range b.columns {
+		cql.WriteString(c)
+		cql.WriteString("=?")
+		if i < len(b.columns)-1 {
+			cql.WriteByte(',')
+		}
+	}
+	names = append(names, b.columns...)
+	cql.WriteByte(' ')
+
+	names = append(names, b.where.writeCql(&cql)...)
+	names = append(names, b._if.writeCql(&cql)...)
+
+	if b.exists {
+		cql.WriteString("IF EXISTS ")
+	}
+
+	stmt = cql.String()
+	return
+}
+
+// Table sets the table to be updated.
+func (b *UpdateBuilder) Table(table string) *UpdateBuilder {
+	b.table = table
+	return b
+}
+
+func (b *UpdateBuilder) Timestamp(t time.Time) *UpdateBuilder {
+	b.using.timestamp = t
+	return b
+}
+
+func (b *UpdateBuilder) TTL(d time.Duration) *UpdateBuilder {
+	b.using.ttl = d
+	return b
+}
+
+func (b *UpdateBuilder) Set(columns ...string) *UpdateBuilder {
+	b.columns = append(b.columns, columns...)
+	return b
+}
+
+func (b *UpdateBuilder) Where(e ...expr) *UpdateBuilder {
+	b.where = append(b.where, e...)
+	return b
+}
+
+func (b *UpdateBuilder) If(e ...expr) *UpdateBuilder {
+	b._if = append(b._if, e...)
+	return b
+}
+
+func (b *UpdateBuilder) Existing() *UpdateBuilder {
+	b.exists = true
+	return b
+}

qb/update_test.go

@@ -0,0 +1,106 @@
+package qb
+
+import (
+	"testing"
+	"time"
+
+	"github.com/google/go-cmp/cmp"
+)
+
+func TestUpdateBuilder(t *testing.T) {
+	m := mockExpr{
+		cql:   "expr",
+		names: []string{"expr"},
+	}
+
+	table := []struct {
+		B *UpdateBuilder
+		N []string
+		S string
+	}{
+		// Basic test for update
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m),
+			S: "UPDATE cycling.cyclist_name SET id=?,user_uuid=?,firstname=? WHERE expr ",
+			N: []string{"id", "user_uuid", "firstname", "expr"},
+		},
+		// Change table name
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).Table("Foobar"),
+			S: "UPDATE Foobar SET id=?,user_uuid=?,firstname=? WHERE expr ",
+			N: []string{"id", "user_uuid", "firstname", "expr"},
+		},
+		// Add SET
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).Set("stars"),
+			S: "UPDATE cycling.cyclist_name SET id=?,user_uuid=?,firstname=?,stars=? WHERE expr ",
+			N: []string{"id", "user_uuid", "firstname", "stars", "expr"},
+		},
+		// Add WHERE
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).Where(mockExpr{
+				cql:   "expr_1",
+				names: []string{"expr_1"},
+			}, mockExpr{
+				cql:   "expr_2",
+				names: []string{"expr_2"},
+			}),
+			S: "UPDATE cycling.cyclist_name SET id=?,user_uuid=?,firstname=? WHERE expr AND expr_1 AND expr_2 ",
+			N: []string{"id", "user_uuid", "firstname", "expr", "expr_1", "expr_2"},
+		},
+		// Add IF
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).If(mockExpr{
+				cql:   "expr_1",
+				names: []string{"expr_1"},
+			}, mockExpr{
+				cql:   "expr_2",
+				names: []string{"expr_2"},
+			}),
+			S: "UPDATE cycling.cyclist_name SET id=?,user_uuid=?,firstname=? WHERE expr IF expr_1 AND expr_2 ",
+			N: []string{"id", "user_uuid", "firstname", "expr", "expr_1", "expr_2"},
+		},
+		// Add TTL
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).TTL(time.Second * 86400),
+			S: "UPDATE cycling.cyclist_name USING TTL 86400 SET id=?,user_uuid=?,firstname=? WHERE expr ",
+			N: []string{"id", "user_uuid", "firstname", "expr"},
+		},
+		// Add TIMESTAMP
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).Timestamp(time.Unix(0, 0).Add(time.Microsecond * 123456789)),
+			S: "UPDATE cycling.cyclist_name USING TIMESTAMP 123456789 SET id=?,user_uuid=?,firstname=? WHERE expr ",
+			N: []string{"id", "user_uuid", "firstname", "expr"},
+		},
+		// Add IF EXISTS
+		{
+			B: Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname").Where(m).Existing(),
+			S: "UPDATE cycling.cyclist_name SET id=?,user_uuid=?,firstname=? WHERE expr IF EXISTS ",
+			N: []string{"id", "user_uuid", "firstname", "expr"},
+		},
+	}
+
+	for _, test := range table {
+		stmt, names, err := test.B.ToCql()
+		if err != nil {
+			t.Error("unexpected error", err)
+		}
+		if diff := cmp.Diff(test.S, stmt); diff != "" {
+			t.Error(diff)
+		}
+		if diff := cmp.Diff(test.N, names); diff != "" {
+			t.Error(diff)
+		}
+	}
+}
+
+func BenchmarkUpdateBuilder(b *testing.B) {
+	m := mockExpr{
+		cql:   "expr",
+		names: []string{"expr"},
+	}
+	b.ResetTimer()
+	for i := 0; i < b.N; i++ {
+		Update("cycling.cyclist_name").Set("id", "user_uuid", "firstname", "stars").Where(m)
+	}
+}