Load testing that says what happened.

name: checkout
type: load                     # how the result should be read
base_url: https://staging.example.com

feeders:
  accounts: { path: accounts.csv, mode: per_vu }

load:
  stages:
    - { duration: 30s, target: 200 }
    - { duration: 5m,  target: 200 }
  warmup: 30s

users:
  - name: shopper
    weight: 7
    wait: 2s..8s
    on_start:
      - name: login
        post: /auth/login
        json: { user: "${accounts.user}", pass: "${accounts.pass}" }
        extract: { token: { json: data.token } }
    flow:
      - { name: api/items, get: /api/items }
      - { name: api/cart,  post: /api/cart,     group: checkout }
      - { name: api/pay,   post: /api/checkout, group: checkout,
          check: { json: { status: confirmed } } }

thresholds:
  - "p95(checkout) < 1s"       # the journey, not the call
  - "error_rate < 1%"
  - "check_rate > 99%"

s := surge.New("shop")
s.BaseURL("https://staging.example.com").
	ClosedStages(
		surge.Stage{Duration: 30 * time.Second, Target: 200},
		surge.Stage{Duration: 5 * time.Minute, Target: 200},
	).
	Thresholds("p95 < 500ms", "error_rate < 1%")

buyer := s.User("buyer", 7).Wait(2*time.Second, 8*time.Second)

buyer.OnStart(func(c *surge.Ctx) error {
	r := c.POST("/auth/login", surge.JSON(creds))
	c.Set("token", r.JSON("data.token"))
	return r.Err()
})

buyer.Task("checkout", 1, func(c *surge.Ctx) error {
	return c.Group("checkout", func() error {
		c.POST("/api/cart", surge.Bearer(c.Str("token")))
		r := c.POST("/api/checkout", surge.Bearer(c.Str("token")))
		c.Check("order confirmed", r.JSON("status") == "confirmed")
		return r.Err()
	})
})

s.RunMain()   // -vus, -rate, -duration, -html, -json, -agents

on_start:
  - { name: ws/connect, ws: /game, as: game }

wait: 1s..3s

flow:
  - name: ws/join
    on: game
    send: '{"op":"join","room":"${room}"}'
    receive: true               # send + receive = one round trip
    check: { body_contains: '"ok":true' }

  - name: ws/tick
    on: game
    receive: true               # on its own: the wait, which is the push
    repeat: 5