blob: 5207068c2199f27dc9f9a368a172efda319c71d6 [file] [log] [blame]
// Copyright 2016 The Vanadium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
package commands
import (
"fmt"
"io"
"strconv"
"strings"
"v.io/v23/context"
"v.io/v23/syncbase"
"v.io/x/lib/cmdline"
)
var cmdSelect = &cmdline.Command{
// TODO(zsterling): Wrap select in exec and add more general queries/deletes.
Name: "select",
Short: "Display particular rows, or parts of rows",
Long: `
Display particular rows, or parts of rows.
`,
ArgsName: "<field_1,field_2,...> from <collection> [where <field> = <value>]",
ArgsLong: `
<field_n> specifies a field in the collection <collection>.
`,
Runner: SbRunner(selectFunc),
}
func selectFunc(ctx *context.T, db syncbase.Database, env *cmdline.Env, args []string) error {
return queryExec(ctx, env.Stdout, db, "select "+strings.Join(args, " "))
}
// Split an error message into an offset and the remaining (i.e., rhs of offset) message.
// The convention for syncql is "<module><optional-rpc>[offset]<remaining-message>".
func splitError(err error) (int64, string) {
errMsg := err.Error()
idx1 := strings.Index(errMsg, "[")
idx2 := strings.Index(errMsg, "]")
if idx1 == -1 || idx2 == -1 {
return 0, errMsg
}
offsetString := errMsg[idx1+1 : idx2]
offset, err := strconv.ParseInt(offsetString, 10, 64)
if err != nil {
return 0, errMsg
}
return offset, errMsg[idx2+1:]
}
func queryExec(ctx *context.T, w io.Writer, d syncbase.Database, q string) error {
columnNames, rs, err := d.Exec(ctx, q)
if err != nil {
off, msg := splitError(err)
return fmt.Errorf("\n%s\n%s^\n%d: %s", q, strings.Repeat(" ", int(off)), off+1, msg)
}
return flagFormat.NewWriter(w).Write(columnNames, rs)
}