handler.go

package main

import (
    "net/http"

    sarama "gopkg.in/Shopify/sarama.v1"
)

// KafkaController allows us to attach a producer
// to our handlers
type KafkaController struct {
    producer sarama.AsyncProducer
}

// Handler grabs a message from a GET parama and
// send it to the kafka queue asynchronously
func (c *KafkaController) Handler(w http.ResponseWriter, r *http.Request) {
    if err := r.ParseForm(); err != nil {
        w.WriteHeader(http.StatusBadRequest)
        return
    }

    msg := r.FormValue("msg")
    if msg == "" {
        w.WriteHeader(http.StatusBadRequest)
        w.Write([]byte("msg must be set"))
        return
    }
    c.producer.Input() <- &sarama.ProducerMessage{Topic: 
    "example", Key: nil, Value: 
    sarama.StringEncoder(r.FormValue("msg"))}
    w.WriteHeader(http.StatusOK)
}