hub

type AgentInfo struct {
	ID            string
	Version       string
	System        *agentv1.SystemInfo
	ConnectedAt   time.Time
	LastHeartbeat time.Time // zero until the first heartbeat
	LastMetrics   *agentv1.MetricsReport
	// ProtocolVersion is the version negotiated for the connection.
	ProtocolVersion uint32
	// Compat tells how the agent's release relates to the hub's.
	Compat update.Compat
}

type AgentSource interface {
	Agents() []AgentInfo
	// StaleAfter is how long an agent may stay silent before it is reported as
	// stale.
	StaleAfter() time.Duration
	// Metrics returns the recent metrics of an agent, oldest first; known is
	// false for an agent the hub never saw.
	Metrics(agentID string) (samples []MetricsSample, known bool)
	// Subscribe returns a channel of JSON events (see events.go) and a function
	// that ends the subscription. The channel is closed if the subscriber falls
	// too far behind.
	Subscribe() (events <-chan []byte, cancel func())
}

type Deps struct {
	// UI holds the compiled dashboard.
	UI fs.FS
	// Agents, Layouts and Log may be nil in tests; the agent list is then empty
	// and the layout endpoints answer 404.
	Agents  AgentSource
	Layouts LayoutStore
	Log     *slog.Logger
	// Auth protects the API. A nil Auth leaves it open, which is only meant for
	// tests.
	Auth *auth.Service
	// Fleet enrolls and revokes remote agents. May be nil in tests; the
	// endpoints then answer 404.
	Fleet FleetControl
	// Updates reports and steers the updates of the hub. May be nil in tests;
	// the endpoints then answer 404.
	Updates UpdateControl
	// Rollout updates the managed servers to the version of the hub. May be nil
	// in tests; the endpoints then answer 404.
	Rollout RolloutControl
}

type Enrollment struct {
	Token         string
	Name          string
	ExpiresAt     time.Time
	CAFingerprint string
	AgentPort     int
}

type FleetControl interface {
	CreateEnrollment(ctx context.Context, by, name string) (Enrollment, error)
	RevokeAgent(ctx context.Context, by, id string) error
	RenameAgent(ctx context.Context, by, id, name string) error
}

type Hub struct {
	// contains filtered or unexported fields
}

type LayoutStore interface {
	// Layout returns the stored layout; found is false if the user has none.
	Layout(ctx context.Context, userID int64) (layout json.RawMessage, updatedAt time.Time, found bool, err error)
	SetLayout(ctx context.Context, userID int64, layout json.RawMessage) error
}

type MetricsSample struct {
	At     time.Time
	Report *agentv1.MetricsReport
}

type Option func(*Hub)

type Rejection struct {
	At      time.Time
	Version string
	Message string
}

type RolloutAgent struct {
	ID       string `json:"id"`
	Hostname string `json:"hostname,omitempty"`
	From     string `json:"from"`
	Status   string `json:"status"`
	Message  string `json:"message,omitempty"`
}

type RolloutControl interface {
	RolloutStatus(ctx context.Context) (RolloutStatus, error)
	StartRollout(ctx context.Context, by string, opts RolloutOptions) (RolloutStatus, error)
	StopRollout(ctx context.Context, by string) (RolloutStatus, error)
}

type RolloutOptions struct {
	// Agents limits the rollout to these servers; empty means every candidate.
	Agents []string `json:"agents"`
	// WaveSize is how many servers are updated at the same time (default 1).
	// The rollout stops at the first failure.
	WaveSize int `json:"wave_size"`
}

type RolloutStatus struct {
	// Target is the version the servers are updated to: the one this hub runs.
	Target string `json:"target"`
	State  string `json:"state"`
	// Candidates are the connected servers that run an older version and would
	// be updated by a new rollout.
	Candidates []RolloutAgent `json:"candidates"`
	// Agents is what the last rollout did.
	Agents     []RolloutAgent `json:"agents"`
	WaveSize   int            `json:"wave_size,omitempty"`
	StartedBy  string         `json:"started_by,omitempty"`
	StartedAt  *time.Time     `json:"started_at"`
	FinishedAt *time.Time     `json:"finished_at"`
}

type UpdateControl interface {
	Status(ctx context.Context) (update.Status, error)
	SetSettings(ctx context.Context, by string, s update.Settings) (update.Status, error)
	Check(ctx context.Context) (update.Status, error)
	Download(ctx context.Context, by string) (update.Status, error)
	Apply(ctx context.Context, by string) (update.Status, error)
}