distribution/vendor/github.com/garyburd/redigo/redis/reply.go

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// Copyright 2012 Gary Burd
//
// Licensed under the Apache License, Version 2.0 (the "License"): you may
// not use this file except in compliance with the License. You may obtain
// a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
// WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
// License for the specific language governing permissions and limitations
// under the License.
package redis
import (
"errors"
"fmt"
"strconv"
)
// ErrNil indicates that a reply value is nil.
var ErrNil = errors.New("redigo: nil returned")
// Int is a helper that converts a command reply to an integer. If err is not
// equal to nil, then Int returns 0, err. Otherwise, Int converts the
// reply to an int as follows:
//
// Reply type Result
// integer int(reply), nil
// bulk string parsed reply, nil
// nil 0, ErrNil
// other 0, error
func Int(reply interface{}, err error) (int, error) {
if err != nil {
return 0, err
}
switch reply := reply.(type) {
case int64:
x := int(reply)
if int64(x) != reply {
return 0, strconv.ErrRange
}
return x, nil
case []byte:
n, err := strconv.ParseInt(string(reply), 10, 0)
return int(n), err
case nil:
return 0, ErrNil
case Error:
return 0, reply
}
return 0, fmt.Errorf("redigo: unexpected type for Int, got type %T", reply)
}
// Int64 is a helper that converts a command reply to 64 bit integer. If err is
// not equal to nil, then Int returns 0, err. Otherwise, Int64 converts the
// reply to an int64 as follows:
//
// Reply type Result
// integer reply, nil
// bulk string parsed reply, nil
// nil 0, ErrNil
// other 0, error
func Int64(reply interface{}, err error) (int64, error) {
if err != nil {
return 0, err
}
switch reply := reply.(type) {
case int64:
return reply, nil
case []byte:
n, err := strconv.ParseInt(string(reply), 10, 64)
return n, err
case nil:
return 0, ErrNil
case Error:
return 0, reply
}
return 0, fmt.Errorf("redigo: unexpected type for Int64, got type %T", reply)
}
var errNegativeInt = errors.New("redigo: unexpected value for Uint64")
// Uint64 is a helper that converts a command reply to 64 bit integer. If err is
// not equal to nil, then Int returns 0, err. Otherwise, Int64 converts the
// reply to an int64 as follows:
//
// Reply type Result
// integer reply, nil
// bulk string parsed reply, nil
// nil 0, ErrNil
// other 0, error
func Uint64(reply interface{}, err error) (uint64, error) {
if err != nil {
return 0, err
}
switch reply := reply.(type) {
case int64:
if reply < 0 {
return 0, errNegativeInt
}
return uint64(reply), nil
case []byte:
n, err := strconv.ParseUint(string(reply), 10, 64)
return n, err
case nil:
return 0, ErrNil
case Error:
return 0, reply
}
return 0, fmt.Errorf("redigo: unexpected type for Uint64, got type %T", reply)
}
// Float64 is a helper that converts a command reply to 64 bit float. If err is
// not equal to nil, then Float64 returns 0, err. Otherwise, Float64 converts
// the reply to an int as follows:
//
// Reply type Result
// bulk string parsed reply, nil
// nil 0, ErrNil
// other 0, error
func Float64(reply interface{}, err error) (float64, error) {
if err != nil {
return 0, err
}
switch reply := reply.(type) {
case []byte:
n, err := strconv.ParseFloat(string(reply), 64)
return n, err
case nil:
return 0, ErrNil
case Error:
return 0, reply
}
return 0, fmt.Errorf("redigo: unexpected type for Float64, got type %T", reply)
}
// String is a helper that converts a command reply to a string. If err is not
// equal to nil, then String returns "", err. Otherwise String converts the
// reply to a string as follows:
//
// Reply type Result
// bulk string string(reply), nil
// simple string reply, nil
// nil "", ErrNil
// other "", error
func String(reply interface{}, err error) (string, error) {
if err != nil {
return "", err
}
switch reply := reply.(type) {
case []byte:
return string(reply), nil
case string:
return reply, nil
case nil:
return "", ErrNil
case Error:
return "", reply
}
return "", fmt.Errorf("redigo: unexpected type for String, got type %T", reply)
}
// Bytes is a helper that converts a command reply to a slice of bytes. If err
// is not equal to nil, then Bytes returns nil, err. Otherwise Bytes converts
// the reply to a slice of bytes as follows:
//
// Reply type Result
// bulk string reply, nil
// simple string []byte(reply), nil
// nil nil, ErrNil
// other nil, error
func Bytes(reply interface{}, err error) ([]byte, error) {
if err != nil {
return nil, err
}
switch reply := reply.(type) {
case []byte:
return reply, nil
case string:
return []byte(reply), nil
case nil:
return nil, ErrNil
case Error:
return nil, reply
}
return nil, fmt.Errorf("redigo: unexpected type for Bytes, got type %T", reply)
}
// Bool is a helper that converts a command reply to a boolean. If err is not
// equal to nil, then Bool returns false, err. Otherwise Bool converts the
// reply to boolean as follows:
//
// Reply type Result
// integer value != 0, nil
// bulk string strconv.ParseBool(reply)
// nil false, ErrNil
// other false, error
func Bool(reply interface{}, err error) (bool, error) {
if err != nil {
return false, err
}
switch reply := reply.(type) {
case int64:
return reply != 0, nil
case []byte:
return strconv.ParseBool(string(reply))
case nil:
return false, ErrNil
case Error:
return false, reply
}
return false, fmt.Errorf("redigo: unexpected type for Bool, got type %T", reply)
}
// MultiBulk is deprecated. Use Values.
func MultiBulk(reply interface{}, err error) ([]interface{}, error) { return Values(reply, err) }
// Values is a helper that converts an array command reply to a []interface{}.
// If err is not equal to nil, then Values returns nil, err. Otherwise, Values
// converts the reply as follows:
//
// Reply type Result
// array reply, nil
// nil nil, ErrNil
// other nil, error
func Values(reply interface{}, err error) ([]interface{}, error) {
if err != nil {
return nil, err
}
switch reply := reply.(type) {
case []interface{}:
return reply, nil
case nil:
return nil, ErrNil
case Error:
return nil, reply
}
return nil, fmt.Errorf("redigo: unexpected type for Values, got type %T", reply)
}
// Strings is a helper that converts an array command reply to a []string. If
// err is not equal to nil, then Strings returns nil, err. Nil array items are
// converted to "" in the output slice. Strings returns an error if an array
// item is not a bulk string or nil.
func Strings(reply interface{}, err error) ([]string, error) {
if err != nil {
return nil, err
}
switch reply := reply.(type) {
case []interface{}:
result := make([]string, len(reply))
for i := range reply {
if reply[i] == nil {
continue
}
p, ok := reply[i].([]byte)
if !ok {
return nil, fmt.Errorf("redigo: unexpected element type for Strings, got type %T", reply[i])
}
result[i] = string(p)
}
return result, nil
case nil:
return nil, ErrNil
case Error:
return nil, reply
}
return nil, fmt.Errorf("redigo: unexpected type for Strings, got type %T", reply)
}
// Ints is a helper that converts an array command reply to a []int. If
// err is not equal to nil, then Ints returns nil, err.
func Ints(reply interface{}, err error) ([]int, error) {
var ints []int
if reply == nil {
return ints, ErrNil
}
values, err := Values(reply, err)
if err != nil {
return ints, err
}
if err := ScanSlice(values, &ints); err != nil {
return ints, err
}
return ints, nil
}
// StringMap is a helper that converts an array of strings (alternating key, value)
// into a map[string]string. The HGETALL and CONFIG GET commands return replies in this format.
// Requires an even number of values in result.
func StringMap(result interface{}, err error) (map[string]string, error) {
values, err := Values(result, err)
if err != nil {
return nil, err
}
if len(values)%2 != 0 {
return nil, errors.New("redigo: StringMap expects even number of values result")
}
m := make(map[string]string, len(values)/2)
for i := 0; i < len(values); i += 2 {
key, okKey := values[i].([]byte)
value, okValue := values[i+1].([]byte)
if !okKey || !okValue {
return nil, errors.New("redigo: ScanMap key not a bulk string value")
}
m[string(key)] = string(value)
}
return m, nil
}