"Could not book the appointment. Please try again later or contact the organizer."

[ChristophWurst]

Steps to reproduce

1. Create a public appointment config
2. Have someone book a meeting with you

Expected behavior

They can book

Actual behaviour

They get an error

Calendar app version

4.5

CalDAV-clients used

No response

Browser

No response

Client operating system

No response

Server operating system

No response

Web server

None

Database engine version

None

PHP engine version

None

Nextcloud version

No response

Updated from an older installed version or fresh install

None

List of activated apps

No response

Nextcloud configuration

No response

Web server error log

No response

Log file

No response

Browser log

No response

Additional info

No response

[miaulalala]

From the logs (unobfuscated data is with me):

{
  "reqId": "avksJbkPTQlIGmjRSJY7",
  "level": 2,
  "time": "2023-11-30T10:22:40+00:00",
  "remoteAddr": "197.216.105.46",
  "user": "--",
  "app": "calendar",
  "method": "POST",
  "url": "/apps/calendar/appointment/84/book",
  "message": "No slot available for start: 1701941400, end: 1701944100, config id: 84",
  "userAgent": "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/119.0.0.0 Safari/537.36 Edg/119.0.0.0",
  "version": "28.0.0.7",
  "exception": {
    "Exception": "OCA\\Calendar\\Exception\\NoSlotFoundException",
    "Message": "Could not find slot for booking",
    "Code": 0,
    "Trace": [
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/apps/calendar/lib/Controller/BookingController.php",
        "line": 188,
        "function": "book",
        "class": "OCA\\Calendar\\Service\\Appointments\\BookingService",
        "type": "->",
        "args": [
          [
            "OCA\\Calendar\\Db\\AppointmentConfig",
            84
          ],
          1701941400,
          1701944100,
          "Africa/Luanda",
          "XXX YYY",
          "xxx@yyy.com",
          "ABCDEFG"
        ]
      },
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/lib/private/AppFramework/Http/Dispatcher.php",
        "line": 230,
        "function": "bookSlot",
        "class": "OCA\\Calendar\\Controller\\BookingController",
        "type": "->",
        "args": [
          84,
          1701941400,
          1701944100,
          "XXX YYY",
          "xxx@yyy.com",
          "ABCDEFG",
          "Africa/Luanda"
        ]
      },
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/lib/private/AppFramework/Http/Dispatcher.php",
        "line": 137,
        "function": "executeController",
        "class": "OC\\AppFramework\\Http\\Dispatcher",
        "type": "->",
        "args": [
          [
            "OCA\\Calendar\\Controller\\BookingController"
          ],
          "bookSlot"
        ]
      },
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/lib/private/AppFramework/App.php",
        "line": 184,
        "function": "dispatch",
        "class": "OC\\AppFramework\\Http\\Dispatcher",
        "type": "->",
        "args": [
          [
            "OCA\\Calendar\\Controller\\BookingController"
          ],
          "bookSlot"
        ]
      },
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/lib/private/Route/Router.php",
        "line": 315,
        "function": "main",
        "class": "OC\\AppFramework\\App",
        "type": "::",
        "args": [
          "OCA\\Calendar\\Controller\\BookingController",
          "bookSlot",
          [
            "OC\\AppFramework\\DependencyInjection\\DIContainer"
          ],
          [
            "84",
            "calendar.booking.bookSlot"
          ]
        ]
      },
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/lib/base.php",
        "line": 1069,
        "function": "match",
        "class": "OC\\Route\\Router",
        "type": "->",
        "args": [
          "/apps/calendar/appointment/84/book"
        ]
      },
      {
        "file": "/var/www/cloud.nextcloud.com/nextcloud/index.php",
        "line": 37,
        "function": "handleRequest",
        "class": "OC",
        "type": "::",
        "args": []
      }
    ],
    "File": "/var/www/cloud.nextcloud.com/nextcloud/apps/calendar/lib/Service/Appointments/BookingService.php",
    "Line": 164,
    "message": "No slot available for start: 1701941400, end: 1701944100, config id: 84",
    "exception": {},
    "CustomMessage": "No slot available for start: 1701941400, end: 1701944100, config id: 84"
  }
}

[miaulalala]

Asked for debug logs to be enabled. I think it's \OCA\Calendar\Service\Appointments\BookingService::getAvailableSlots that's not working properly. We pass two timestamps; when extrapolating for the day, it's the timestamp for the whole day, but when booking it's the start and end date of the slot. The calculations could be off my a few seconds and the slot wouldn't fit.

[miaulalala]

We're missing the log lines from the conflict checker which means the slots are already empty. adding more logging just to be sure.

[bentuna]

After further testing with Nextcloud 28.0.2 and Calendar 4.6.5, we can say that:

• the error occurs with every duration above 60 minutes
• in every case where duration > increment
• in every second slot from the available slot list, when duration is double of increment.

[ChristophWurst]

@bentuna please file a new ticket so this isn't lost.