Pipeline with Redigo

pipeline.go

package redis

import (
	redigo "github.com/garyburd/redigo/redis"
)

// HMGET is a common usage of Redis command HMGET
func (r *redis) HMGET(key string, fields ...string) ([]string, error) {
	conn := r.Pool.Get()
	defer conn.Close()

	cmd := append([]string{key}, fields...)

	payload := make([]interface{}, len(cmd))
	for n, c := range cmd {
		payload[n] = c
	}

	result := make(map[string]string)
	resp, err := redigo.Strings(conn.Do("HMGET", payload...))
	if err != nil {
		return nil, err
	}

	return resp, nil
}

// HMGETP is HMGET with Pipeline
func (r *redis) HMGETP(keys []string, fields ...string) ([]interface{}, error) {
	conn := r.Pool.Get()
	defer conn.Close()

	// open pipeline, generate chain of commands
	for _, key := range keys {
		cmd := append([]string{key}, fields...)
		payload := make([]interface{}, len(cmd))
		for n, c := range cmd {
			payload[n] = c
		}
		// Send writes the command to the connection's output buffer
		if err := conn.Send("HMGET", payload...); err != nil {
			return nil, err
		}
	}

	// Flush flushes the connection's output buffer to the server.
	if err := conn.Flush(); err != nil {
		return nil, err
	}

	//Receive reads a single reply from the server.
	replies := make([]interface{}, len(keys))
	for i := 0; i < len(keys); i++ {
		reply, err := conn.Receive()
		if err != nil {
			return nil, err
		}
		replies[i] = reply
	}
	resp, err := redigo.Values(replies, nil)
	if err != nil {
		return nil, err
	}

	return resp, nil
}