client_middleware_test.go

package amqprpc

import (
	"bytes"
	"fmt"
	"io"
	"testing"

	amqp "github.com/rabbitmq/amqp091-go"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func traceClientMiddleware(id int, w io.Writer) ClientMiddlewareFunc {
	return func(next SendFunc) SendFunc {
		return func(r *Request) (*amqp.Delivery, error) {
			fmt.Fprint(w, id)

			res, err := next(r)

			fmt.Fprint(w, id)

			return res, err
		}
	}
}

func TestClientMiddlewareChain(t *testing.T) {
	var (
		req = NewRequest()
		b   = bytes.Buffer{}
	)

	mw := ClientMiddlewareChain(
		func(_ *Request) (*amqp.Delivery, error) {
			fmt.Fprintf(&b, "X")

			dx := amqp.Delivery{}

			return &dx, nil
		},
		traceClientMiddleware(1, &b),
		traceClientMiddleware(2, &b),
	)

	res, err := mw(req)

	require.NoError(t, err, "no errors chaining middlewares")
	assert.NotNil(t, res, "result is not nil after passing through middlewares")
	assert.Equal(t, []byte("12X21"), b.Bytes(), "middlewares executed in correct order")
}

func TestClientClientAddMiddlewares(t *testing.T) {
	c := NewClient("")

	assert.Empty(t, c.middlewares, "zero middlewares at start")

	c.AddMiddleware(
		func(n SendFunc) SendFunc {
			return func(r *Request) (*amqp.Delivery, error) {
				return n(r)
			}
		},
	)

	assert.Len(t, c.middlewares, 1, "adding middlewares working")
}