Mercari Microservices Example

Let's explore the Mercari-ish microservices consist of Go, gRPC, Kubernetes and Istio on your laptop!

Microservices

You can find each microservice's implementation and gRPC API definitions under the /services directory.

Gateway

• This is the only microservice which is facing the out side of the Kubernetes cluster and acts as just a proxy.
• This microservice is responsible for authenticate the request by verifying the access token (JWT) with public keys which can be fetched from the Authority microservice.
• This microservice also transcode the JSON requests to the gRPC Protocol Buffers.

Authority

• This microservice is responsible for issuing the access token (JWT) for the customer app.
• This microservice also provides public keys as a gRPC endpoint to make other microservices be able to verify the signature of the access token.

Catalog

• This microservice is responsible for aggregating data from the Customer and the Item microservices to make an API caller easily consume it.
• This microservice acts like a Backend For Frontend (BFF).

Customer

• This microservice is responsible for storing the customer information to the database and providing it as APIs.

Item

• This microservice is responsible for storing the item information to the database and providing it as APIs.

Usage

Prerequisites

• Go
• Docker

Lanuch the Kubernetes cluster

make cluster

This make target does following tasks:

• Launch the Kubernetes cluster on your laptop by using kind.
• Install Istio to the Kubernetes cluster.
• Build Docker images of all microservices placed under the /services directory.
• Deploy all microservices to the Kubernetes cluster.

After this make target will have been finished, you can check the status of microservices with ./script/kubectl which is just a tiny wrapper for kubectl like below:

./script/kubectl get pods --all-namespaces | grep -E '^(gateway|authority|catalog|customer|item)'

authority   app-7b559dfd9f-dcr2v   2/2     Running     0   44s
authority   app-7b559dfd9f-z8c54   2/2     Running     0   44s
catalog     app-67cc897d9c-dhcv7   2/2     Running     0   36s
catalog     app-67cc897d9c-nfk7x   2/2     Running     0   36s
customer    app-565bfc5884-bgb8r   2/2     Running     0   28s
customer    app-565bfc5884-lt6q2   2/2     Running     0   28s
gateway     app-cc456cf4d-nsghg    2/2     Running     0   51s
gateway     app-cc456cf4d-wq47s    2/2     Running     0   51s
item        app-84db48bdf-h7q7b    2/2     Running     0   19s
item        app-84db48bdf-l5mnl    2/2     Running     0   19s

Now, the Mercari-ish service is listening on port 30000, and you can explore it like below!

API

Sign up

curl -s -XPOST -d '{"name":"gopher"}' localhost:30000/auth/signup | jq .

{
    "customer": {
        "id": "ec1fcc77-b565-4477-b609-62bf0c403903",
        "name": "gopher"
    }
}

Sign in

TOKEN=$(curl -s -XPOST -d '{"name":"gopher"}' localhost:30000/auth/signin | jq .access_token -r)

Create a item

curl -s -XPOST -d '{"title":"Keyboard","price":30000}' -H "authorization: bearer $TOKEN" localhost:30000/catalog/items | jq .

{
    "item": {
        "id": "bda92da6-3270-4255-a756-dbe7d0aa333e",
        "customer_id": "ec1fcc77-b565-4477-b609-62bf0c403903",
        "title": "Keyboard",
        "price": "30000"
    }
}

List items

curl -s -XGET -H "authorization: bearer $TOKEN" localhost:30000/catalog/items | jq .

{
    "items": [
        {
            "id": "3c287306-6753-4ab6-acde-d17297e2939e",
            "title": "Keyboard",
            "price": "30000"
        },
        {
            "id": "e0e58243-4138-48e5-8aba-448a8888e2ff",
            "title": "Mobile Phone",
            "price": "10000"
        },
        {
            "id": "0b185d96-d6fa-4eaf-97f6-3f6d2c1649b6",
            "title": "Laptop",
            "price": "20000"
        }
    ]
}

Get a item detail

curl -s -XGET -H "authorization: bearer $TOKEN" localhost:30000/catalog/items/e0e58243-4138-48e5-8aba-448a8888e2ff | jq .

{
    "item": {
        "id": "e0e58243-4138-48e5-8aba-448a8888e2ff",
        "customer_id": "7c0cde05-4df0-47f4-94c4-978dd9f56e5c",
        "customer_name": "goldie",
        "title": "Mobile Phone",
        "price": "10000"
    }
}

Clean up

make clean