| 1 | package calendar |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "encoding/json" |
| 6 | "errors" |
| 7 | "io" |
| 8 | "net" |
| 9 | "net/http" |
| 10 | "os" |
| 11 | |
| 12 | "amadan.net/rastrillo/rastrillo/carlos" |
| 13 | ) |
| 14 | |
| 15 | const scheduleUnsupportedMessage = "calendar: this platform does not support safe scheduled work; update the platform before starting Calendar" |
| 16 | |
| 17 | type unsupportedScheduling struct{} |
| 18 | |
| 19 | func (unsupportedScheduling) Error() string { return scheduleUnsupportedMessage } |
| 20 | |
| 21 | func scheduleControl(ctx context.Context, path string, value any) error { |
| 22 | socket := os.Getenv("CARLOS_CONTROL_SOCKET") |
| 23 | if socket == "" { |
| 24 | return carlos.ErrNotOnCarlos |
| 25 | } |
| 26 | token := os.Getenv("CARLOS_ADMIN_TOKEN") |
| 27 | if token == "" { |
| 28 | return carlos.ErrUnauthorized |
| 29 | } |
| 30 | transport := &http.Transport{DialContext: func(ctx context.Context, _, _ string) (net.Conn, error) { |
| 31 | return (&net.Dialer{}).DialContext(ctx, "unix", socket) |
| 32 | }} |
| 33 | defer transport.CloseIdleConnections() |
| 34 | req, err := http.NewRequestWithContext(ctx, http.MethodGet, "http://carlos"+path, nil) |
| 35 | if err != nil { |
| 36 | return err |
| 37 | } |
| 38 | req.Header.Set("Authorization", "Bearer "+token) |
| 39 | response, err := (&http.Client{Transport: transport}).Do(req) |
| 40 | if err != nil { |
| 41 | return err |
| 42 | } |
| 43 | defer response.Body.Close() |
| 44 | if response.StatusCode == http.StatusUnauthorized { |
| 45 | return carlos.ErrUnauthorized |
| 46 | } |
| 47 | if path == "/schedule-capabilities" && response.StatusCode == http.StatusNotFound { |
| 48 | return unsupportedScheduling{} |
| 49 | } |
| 50 | if response.StatusCode != http.StatusOK { |
| 51 | return &carlos.StatusError{Status: response.StatusCode, Name: scheduledWorkName} |
| 52 | } |
| 53 | return json.NewDecoder(io.LimitReader(response.Body, 1<<20)).Decode(value) |
| 54 | } |
| 55 | |
| 56 | func scheduleCapability(ctx context.Context) error { |
| 57 | var capability struct { |
| 58 | RegistrationFence bool `json:"registration_fence"` |
| 59 | } |
| 60 | if err := scheduleControl(ctx, "/schedule-capabilities", &capability); err != nil { |
| 61 | return err |
| 62 | } |
| 63 | if !capability.RegistrationFence { |
| 64 | return unsupportedScheduling{} |
| 65 | } |
| 66 | return nil |
| 67 | } |
| 68 | |
| 69 | type remoteSchedule struct { |
| 70 | Name string `json:"name"` |
| 71 | Kind string `json:"kind"` |
| 72 | Path string `json:"path"` |
| 73 | NextAt int64 `json:"next_at"` |
| 74 | DueAt int64 `json:"due_at"` |
| 75 | Attempts int `json:"attempts"` |
| 76 | } |
| 77 | |
| 78 | func scheduleArmed(ctx context.Context) (remoteSchedule, error) { |
| 79 | var response struct { |
| 80 | Timers []remoteSchedule `json:"timers"` |
| 81 | } |
| 82 | if err := scheduleControl(ctx, "/schedule", &response); err != nil { |
| 83 | return remoteSchedule{}, err |
| 84 | } |
| 85 | for _, timer := range response.Timers { |
| 86 | if timer.Name == scheduledWorkName { |
| 87 | return timer, nil |
| 88 | } |
| 89 | } |
| 90 | return remoteSchedule{}, nil |
| 91 | } |
| 92 | |
| 93 | func permanentScheduleError(err error) bool { |
| 94 | var unsupported unsupportedScheduling |
| 95 | var status *carlos.StatusError |
| 96 | return errors.As(err, &unsupported) || errors.Is(err, carlos.ErrNotOnCarlos) || errors.Is(err, carlos.ErrUnauthorized) || |
| 97 | errors.Is(err, carlos.ErrDeclaredSchedule) || (errors.As(err, &status) && status.Status >= 400 && status.Status < 500 && status.Status != 408 && status.Status != 429) |
| 98 | } |
| 99 | |
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