Dialogflow Go Webhook

Simple library to create compatible DialogFlow v2 webhooks using Go.

This package is only intended to create webhooks, it doesn't implement the whole DialogFlow API.

⛔ Deprecation Notice

This project is no longer useful since the release of the Go SDK for Dialogflow's v2 API. See this article for a tutorial on how to use the protobuf definition to handle webhook.

Table of Content

• Dialogflow Go Webhook
• ⛔ Deprecation Notice
• Table of Content
• Introduction
  • Goal of this package
  • Disclaimer
• Installation
  • Using dep
  • Using go get
• Usage
  • Handling incoming request
  • Retrieving params and contexts
  • Responding with a fulfillment
• Examples

Introduction

Goal of this package

This package aims to implement a complete way to receive a DialogFlow payload, parse it, and retrieve data stored in the parameters and contexts by providing your own data structures.

It also allows you to format your response properly, the way DialogFlow expects it, including all the message types and platforms. (Such as cards, carousels, quick replies, etc…)

Disclaimer

As DialogFlow's v2 API is still in Beta, there may be breaking changes. If something breaks, please file an issue.

Installation

Using dep

If you're using dep which is the recommended way to vendor your dependencies in your project, simply run this command :

dep ensure -add github.com/leboncoin/dialogflow-go-webhook

Using go get

If your project isn't using dep yet, you can use go get to install this package :

go get github.com/leboncoin/dialogflow-go-webhook

Usage

Import the package github.com/leboncoin/dialogflow-go-webhook and use it with the dialogflow package name. To make your code cleaner, import it as df. All the following examples and usages use the df notation.

Handling incoming request

In this section we'll use the gin router as it has some nice helper functions that will keep the code concise. For an example using the standard http router, see this example.

When DialogFlow sends a request to your webhook, you can unmarshal the incoming data to a df.Request. This, however, will not unmarshal the contexts and the parameters because those are completely dependent on your data models.

package main

import (
	"net/http"

	"github.com/gin-gonic/gin"
	df "github.com/leboncoin/dialogflow-go-webhook"
)

type params struct {
	City   string `json:"city"`
	Gender string `json:"gender"`
	Age    int    `json:"age"`
}

func webhook(c *gin.Context) {
	var err error
	var dfr *df.Request

	if err = c.BindJSON(&dfr); err != nil {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}
}

func main() {
	r := gin.Default()
	r.POST("/webhook", webhook)
	if err := r.Run("127.0.0.1:8001"); err != nil {
		panic(err)
	}
}

Retrieving params and contexts

type params struct {
	City   string `json:"city"`
	Gender string `json:"gender"`
	Age    int    `json:"age"`
}

func webhook(c *gin.Context) {
	var err error
	var dfr *df.Request
	var p params

	if err = c.BindJSON(&dfr); err != nil {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}

	// Retrieve the params of the request
	if err = dfr.GetParams(&p); err != nil {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}
}

In this example we're getting the DialogFlow request and unmarshalling the params to a defined struct. This is why json.RawMessage is used in both the Request.QueryResult.Parameters and in the Request.QueryResult.Contexts.

This also allows you to filter and route according to the action and intent DialogFlow detected, which means that depending on which action you detected, you can unmarshal the parameters and contexts to a completely different data structure.

The same thing can be done for contexts :

type params struct {
	City   string `json:"city"`
	Gender string `json:"gender"`
	Age    int    `json:"age"`
}

func webhook(c *gin.Context) {
	var err error
	var dfr *df.Request
	var p params

	if err = c.BindJSON(&dfr); err != nil {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}

	if err = dfr.GetContext("my-awesome-context", &p); err != nil {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}
}

Responding with a fulfillment

DialogFlow expects you to respond with what is called a fulfillment.

This package supports every rich response type.

func webhook(c *gin.Context) {
	var err error
	var dfr *df.Request
	var p params

	if err = c.BindJSON(&dfr); err != nil {
		c.AbortWithStatus(http.StatusBadRequest)
		return
	}

	// Send back a fulfillment
	dff := &df.Fulfillment{
		FulfillmentMessages: df.Messages{
			df.ForGoogle(df.SingleSimpleResponse("hello", "hello")),
			{RichMessage: df.Text{Text: []string{"hello"}}},
		},
	}
	c.JSON(http.StatusOK, dff)
}

Examples

• Using Gin
• Using http