Just saying that there're some flaws in the Swagger branch. The Documenting RESTful APIs with Swagger.
But it's quite helpful actually since it really makes me dive deep into the code and read everything three, four times.

Hi @nicholasjackson

Nice work on this microservices video's with Golang. Do you plan to add content related to CQRS and EventSourcing with golang? It would be quite interesting to understand the concept.

I have only found this link

https://medium.com/@shijuvar/building-microservices-with-event-sourcing-cqrs-in-go-using-grpc-nats-streaming-and-cockroachdb-983f650452aa

Regards,
Kevin

Hi, and thank you for the great series!

I'm currently after Episode 6, where a JSON validator was introduced to handle validation in PUT and POST requests. It does work for me as in your video but with a one difference. If I use cURL I don't see validation errors while making those requests. It returns only correct HTTP status (Bad Request) but logs only something like parse error: Invalid numeric literal at line 1, column 6. In this case I can only see a printed log message inside the terminal, where the server runs. Oddly enough it does work if using Postman or any other HTTP Client, which display that error in the response from the server.

// products.go
err = prod.Validate()
		if err != nil {
                         // get logged in terminal
			t.l.Printf("[ERROR] validating product: %s\n", err)
			// get returned in response while using Postman but not in cUrl
                         http.Error(
				rw,
				fmt.Sprintf("Error validating product: %s", err),
				http.StatusBadRequest)
			return
		}

It was enough jq to delete from the request.

after swagger and the client generation branches the validator does not work after a successful product is validated, it fails a bad sku or price fine. keeps returning empty requests on posts and puts. A giant refactor without vids to back it up 👎

this is code that i used git clone with no code I typed myself up to episode 8 i was typing it out and it was great for learning 👍

Can you continue the series pls?

Given a list of products like:

⟩ curl localhost:9090/products | jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   630  100   630    0     0   615k      0 --:--:-- --:--:-- --:--:--  615k
[
  {
    "id": 1,
    "name": "Latte",
    "description": "Frothy milky coffee",
    "price": 2.45,
    "sku": "abc323"
  },
  {
    "id": 2,
    "name": "Esspresso",
    "description": "Short and strong coffee without milk",
    "price": 1.99,
    "sku": "fjd34"
  },
  {
    "id": 3,
    "name": "Esspresso",
    "description": "Short and strong coffee without milk",
    "price": 1.99,
    "sku": "fjd34"
  },
  {
    "id": 4,
    "name": "Esspresso",
    "description": "Short and strong coffee without milk",
    "price": 1.99,
    "sku": "fjd34"
  },
  {
    "id": 5,
    "name": "Esspresso",
    "description": "Short and strong coffee without milk",
    "price": 1.99,
    "sku": "fjd34"
  },
  {
    "id": 6,
    "name": "Esspresso",
    "description": "Short and strong coffee without milk",
    "price": 1.99,
    "sku": "fjd34"
  }
]

After deleting one of them the list is not updated as expected:

⟩ curl localhost:9090/products/2 -XDELETE
⟩ curl localhost:9090/products | jq
  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current
                                 Dload  Upload   Total   Spent    Left  Speed
100   198  100   198    0     0  66000      0 --:--:-- --:--:-- --:--:-- 99000
[
  {
    "id": 1,
    "name": "Latte",
    "description": "Frothy milky coffee",
    "price": 2.45,
    "sku": "abc323"
  },
  {
    "id": 3,
    "name": "Esspresso",
    "description": "Short and strong coffee without milk",
    "price": 1.99,
    "sku": "fjd34"
  }
]

Issue

The below validator works for invalid request body, but for a valid body, it initiates a panic

Code sample, to showcase or reproduce:

data/validation.go

func (v *Validation) Validate(i interface{}) ValidationErrors {
	errs := v.validate.Struct(i).(validator.ValidationErrors)

	if len(errs) == 0 {
		return nil
	}

	var returnErrs []ValidationError
	for _, err := range errs {
		// cast the FieldError into our ValidationError and append to the slice
		ve := ValidationError{err.(validator.FieldError)}
		returnErrs = append(returnErrs, ve)
	}

	return returnErrs
}

handlers/post.go :

func (p *Products) Create(rw http.ResponseWriter, r *http.Request) {
	prod := r.Context().Value(KeyProduct{}).(data.Product) // Panic originate here. Check below for struct definiton

	p.l.Printf("[DEBUG] Inserting product: %#v\n", prod)
	data.AddProduct(prod)
}

data/products.go

// data.Product
type Product struct {

	ID int `json:"id"` // Unique identifier for the product

	Name string `json:"name" validate:"required"`

	Description string `json:"description"`

	SKU string `json:"sku" validate:"sku"`
}

Stack Trace:

products-api 2020/07/04 17:04:27 http: panic serving 127.0.0.1:47468: interface conversion: interface {} is *data.Product, not data.Product
goroutine 50 [running]:
net/http.(*conn).serve.func1(0xc0005fe0a0)
        /usr/local/go/src/net/http/server.go:1772 +0x139
panic(0x951fe0, 0xc00030a480)
        /usr/local/go/src/runtime/panic.go:973 +0x3e3
github.com/nicholasjackson/building-microservices-youtube/product-api/handlers.(*Products).Create(0xc0003192c0, 0xaa9320, 0xc00046a000, 0xc000400400)
        /tmp/building-microservices-youtube/product-api/handlers/post.go:20 +0x349
net/http.HandlerFunc.ServeHTTP(0xc000319510, 0xaa9320, 0xc00046a000, 0xc000400400)
        /usr/local/go/src/net/http/server.go:2012 +0x44
github.com/nicholasjackson/building-microservices-youtube/product-api/handlers.(*Products).MiddlewareValidateProduct.func1(0xaa9320, 0xc00046a000, 0xc000400200)
        /tmp/building-microservices-youtube/product-api/handlers/middleware.go:42 +0x553
net/http.HandlerFunc.ServeHTTP(0xc00027c0a0, 0xaa9320, 0xc00046a000, 0xc000400200)
        /usr/local/go/src/net/http/server.go:2012 +0x44
github.com/gorilla/mux.(*Router).ServeHTTP(0xc000156300, 0xaa9320, 0xc00046a000, 0xc000400000)
        /home/ayman/go/pkg/mod/github.com/gorilla/[email protected]/mux.go:212 +0xe2
net/http.serverHandler.ServeHTTP(0xc00055c1c0, 0xaa9320, 0xc00046a000, 0xc000400000)
        /usr/local/go/src/net/http/server.go:2807 +0xa3
net/http.(*conn).serve(0xc0005fe0a0, 0xaaa460, 0xc00021c040)
        /usr/local/go/src/net/http/server.go:1895 +0x86c
created by net/http.(*Server).Serve
        /usr/local/go/src/net/http/server.go:2933 +0x35c

Could it be the version 10 from go validator has broken the implementation? I have cloned your repo and checked out episode_7 branch and it throws the above error for valid requests.

Hi Nic,

I hope you are well 👍

Two important questions:

1. Can you cover Docker and cloud deployment for microservices written in Go?
2. Will the service continue?

Microservice deployment is super important would be great to finish this tutorial with full deployment with docker etc..

Bests,

Sean.

protoc -I protos/ protos/currency.proto --go_out=plugins=grpc:protos/currency
--go_out: protoc-gen-go: plugins are not supported; use 'protoc --go-grpc_out=...' to generate gRPC

See https://grpc.io/docs/languages/go/quickstart/#regenerate-grpc-code for more information.

F:\gocode\pkg\mod\github.com\nicholasjackson\building-microservices-youtube\[email protected]\data\products.go:55:11: undefined: "github.com/nicholasjackson/building-microservices-youtube/currency/protos/currency".Currency_SubscribeRatesClient