notify

type Alert struct {
	Workflow    string
	RunID       string
	Status      string
	Trigger     string
	Attempts    int
	LogicalDate *time.Time
	Err         string

	// Step is the node that failed. It arrives as a field of its own, and not
	// only embedded in the error text, because it is the first thing whoever is
	// on call looks for: "which step?" before "why?".
	Step string

	// LogExcerpt is the last few lines of that step's output, read from
	// `task_runs.log`. Without it the alert says something failed; with it the
	// alert says what failed and why, without anyone opening the screen at
	// 4am.
	LogExcerpt string

	// The workflow's tags become the message's "Domain" and "Pipeline" fields --
	// in Kestra that came from `labels`, and it is what makes an alert
	// actionable without opening the screen.
	Tags []string

	// BaseURL of the UI, for the run's direct link. Empty means no link.
	BaseURL string
}

type Notificador interface {
	Failed(ctx context.Context, a Alert) error
}

type Report struct {
	From, To    time.Time
	Environment string

	Runs      int
	Succeeded int
	Failed    int

	// Workflows carries the per-pipeline numbers, and it is deliberately not a
	// map: the order is part of the message.
	Workflows []WorkflowInsight
}

type Reporter interface {
	Report(ctx context.Context, r Report) error
}

type Slack struct {
	Webhook string
	Client  *http.Client

	// Ambiente appears in the header ("prod", "dev"). Without it, a staging
	// alert at three in the morning is indistinguishable from a production
	// one.
	Environment string
}

type WorkflowInsight struct {
	Slug   string
	Runs   int
	Failed int

	// Durations of the runs that FINISHED. A run still going has no duration,
	// and counting it as zero would drag every average down at exactly the
	// moment something is stuck.
	Min, Avg, Max time.Duration

	// Rows and Bytes come from the SDK's stage numbers, summed over the
	// SUCCESSFUL attempts only. Counting a failed attempt's rows would report
	// work that was rolled back, and counting every attempt of a retried step
	// would report the same rows twice.
	//
	// Zero for a step that is not an SDK one, which is most of them, and that
	// is why the message leaves the column out rather than printing 0.
	Rows  int64
	Bytes int64
}