[Discussion] `request events.APIGatewayProxyRequest` how request.Path and request.PathParameters["id"] work

[afzal442]

I came across aws lambda with go recently. I was playing around how to make request to query the list of items required. I wonder how I can make Path string and PathParameters map[string]string in the scenario like how to make a GET/POST HTTP request for other routes like bookInfo/viewAll etc.? In my case http://localhost:3000/articleInfo/?list=1 works fine.

Here is the code which I am trying to build and run as below;

import (
	"fmt"
	"log"
	"net/http"
	"os"
	"regexp"
	"strconv"

	"github.com/aws/aws-lambda-go/events"
	"github.com/aws/aws-lambda-go/lambda"
)

type nwarticle struct {
	Title  string  `json:"title"`
	Author string  `json:"author"`
	Price  float64 `json:"price"`
	Review string  `json:"review"`
	Rating float64 `json:"rating"`
}

// article represents data about a record article.
type article struct {
	ID     string  `json:"id"`
	Title  string  `json:"title"`
	Author string  `json:"author"`
	Price  float64 `json:"price"`
	Review string  `json:"review"`
	Rating float64 `json:"rating"`
}

// articles slice to seed record article data.
var articles = []article{
	{ID: "1", Title: "Let's GO", Author: "John Doe", Price: 56.99, Review: "Very Good", Rating: 4},
	{ID: "2", Title: "the three mistakes of my life", Author: "Chetan", Price: 17.99, Review: "Good", Rating: 3.5},
	{ID: "3", Title: "3 idiots", Author: "Bhagat", Price: 39.99, Review: "Excellent", Rating: 5},
}

var iRegexp = regexp.MustCompile(`[1-9]`)
var errorLogger = log.New(os.Stderr, "ERROR ", log.Llongfile)

func handler(request events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {

	i := request.QueryStringParameters["list"]
	x, _ := strconv.Atoi(i)
	if iRegexp.MatchString(i) {
		return events.APIGatewayProxyResponse{
			Body:       fmt.Sprintln(articles[x-1]),
			StatusCode: 200,
		}, nil
	}

	// v := request.PathParameters["id"]
	// if v == "viewAll" {
	// 	return list(request)
	// }

	// if request.Path == "/articleInfo/viewAll" {
	// 	return list(request)
	// }

	// if request.HTTPMethod == "GET" {
	// 	return list(request)
	// } else if request.HTTPMethod == "POST" {
	// 	return create(request)
	// }

	// how to handle request paths

	// if request.Path != "/articleInfo/view" {
	// 	return events.APIGatewayProxyResponse{}, errors.New("Non 200 Response found")
	// } else {
	// 	return events.APIGatewayProxyResponse{
	// 		Body:       fmt.Sprintf("%v", articles),
	// 		StatusCode: 200,
	// 	}, nil
	// }

	// if resp.StatusCode != 200 {
	// 	return events.APIGatewayProxyResponse{}, err
	// }

	// ip, err := ioutil.ReadAll(resp.Body)
	// if err != nil {
	// 	return events.APIGatewayProxyResponse{}, err
	// }

	// if len(ip) == 0 {
	// 	return events.APIGatewayProxyResponse{}, ErrNoIP
	// }

	// var newarticle article

	// reqBody, _ := ioutil.ReadAll(request.Body)
	// json.Unmarshal(reqBody, &newarticle)

	// articles = append(articles, newarticle)

	return clientError(http.StatusBadRequest)
}

func serverError(err error) (events.APIGatewayProxyResponse, error) {
	errorLogger.Println(err.Error())

	return events.APIGatewayProxyResponse{
		StatusCode: http.StatusInternalServerError,
		Body:       http.StatusText(http.StatusInternalServerError),
	}, nil
}

// Similarly add a helper for send responses relating to client errors.
func clientError(status int) (events.APIGatewayProxyResponse, error) {
	return events.APIGatewayProxyResponse{
		StatusCode: status,
		Body:       http.StatusText(status),
	}, nil
}

// func list(request events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
// 	return events.APIGatewayProxyResponse{
// 		Body:       fmt.Sprintf("%v", articles),
// 		StatusCode: 200,
// 	}, nil
// }

// func create(request events.APIGatewayProxyRequest) (events.APIGatewayProxyResponse, error) {
// 	var newarticle article

// 	var req *http.Request
// 	reqBody, _ := ioutil.ReadAll(req.Body)
// 	json.Unmarshal(reqBody, &newarticle)

// 	articles = append(articles, newarticle)

// 	return events.APIGatewayProxyResponse{
// 		Body:       fmt.Sprintf("%v", articles),
// 		StatusCode: 200,
// 	}, nil
// }

func main() {
	lambda.Start(handler)
}

[afzal442]

It would be great if you could take a look and suggest here. Thanks

// @acsauk @iph

[afzal442]

@acsauk @iph Any updates here plz?

[acsauk]

Hi @afzal442 - you may have me mixed up with someone else as I don't have any involvement with this project?

[afzal442]

My Apologies to you @acsauk! Plz, ignore this. thanks.

// @iph

[iph]

Hey there!

I haven't written like a line of code in this library, and at best use the library for my own personal fiddling. Because I'm not a contributor, I have all notifications turned off-- so reaching me on github is usually with a 1-2 week~ish delay. If that's an alright turn around time, totally willing to help.

What's the experience today when you uncomment:

	// v := request.PathParameters["id"]
	// if v == "viewAll" {
	// 	return list(request)
	// }

also, I assume the input you are thinking of is: http://localhost:300/?viewAll=1? , if so, wouldn't it be:

	// _, ok := request.PathParameters["viewAll"]
	// if ok {
	// 	return list(request)
	// }

[afzal442]

Thanks so much @iph for jumping here to help me out.

Here I'm looking for how to make use of Path string and PathParameters map[string]string in my case. I have successfully run request.QueryStringParameters["list"] locally, for this, http://localhost:300/?list=1 works fine.

But for the above two, I'm unable to. Like here I use as you mentioned.

v := request.PathParameters["id"]
	if v == "viewAll" {
	 	return list(request)
	 }

The above should trigger only when I use http://localhost:300/viewAll path.

Thanks.

[afzal442]

Any updates here? thanks.

// @iph