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  1. Moodle
  2. MDL-67594

Deprecate supports_recursion() & extend_lock() in the Lock API

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    • MOODLE_39_STABLE
    • MOODLE_310_STABLE
    • MDL-67594-master-2
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      Using the terminal go to the root folder of your moodle instance.

      Test 1 (supports_recursion())

      1. Do a grep for 'supports_recursion' ()

      grep -R supports_recursion

       Confirm that the only results are in:

      • lib/upgrade.txt (notes about the deprecated supports_recursion())
      • lib/classes/lock/lock_factory.php (declaration of the interface method)
      • lib/classes/lock/installation_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/db_record_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/postgres_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/file_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/mysql_lock_factory.php (implementation method and debug message)

      Test 2 (extend_lock())

      1. Using the terminal go to the root folder of your moodle instance.
      2. Do a grep for 'extend_lock'

      grep -R extend_lock

       Confirm that the only results are in:

      • lib/upgrade.txt (notes about the deprecated extend_lock())
      • lib/classes/lock/lock_factory.php (declaration of the interface method)
      • lib/classes/lock/installation_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/db_record_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/postgres_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/file_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/mysql_lock_factory.php (implementation method and debug message)
      • lib/classes/lock/lock.php (used in extend() which will be also deprecated)

      Test 3 (extend())

      1. Using the terminal go to the root folder of your moodle instance.
      2. Do a grep for 'extend'

      grep -R -e "[[:blank:]]extend(" -e ">extend(" --include \*.php --include \*.txt

       Confirm that the only results are in:

      • lib/upgrade.txt (notes about the deprecated extend())
      • lib/classes/lock/lock.php (method declaration and debug message)
      Show
      Using the terminal go to the root folder of your moodle instance. Test 1 (supports_recursion()) Do a grep for 'supports_recursion' () grep -R supports_recursion   Confirm that the only results are in: lib/upgrade.txt (notes about the deprecated supports_recursion()) lib/classes/lock/lock_factory.php (declaration of the interface method) lib/classes/lock/installation_lock_factory.php (implementation method and debug message) lib/classes/lock/db_record_lock_factory.php  (implementation method and debug message) lib/classes/lock/postgres_lock_factory.php  (implementation method and debug message) lib/classes/lock/file_lock_factory.php  (implementation method and debug message) lib/classes/lock/mysql_lock_factory.php  (implementation method and debug message) Test 2 ( extend_lock() ) Using the terminal go to the root folder of your moodle instance. Do a grep for ' extend_lock ' grep -R extend_lock   Confirm that the only results are in: lib/upgrade.txt (notes about the deprecated extend_lock()) lib/classes/lock/lock_factory.php (declaration of the interface method) lib/classes/lock/installation_lock_factory.php (implementation method and debug message) lib/classes/lock/db_record_lock_factory.php  (implementation method and debug message) lib/classes/lock/postgres_lock_factory.php  (implementation method and debug message) lib/classes/lock/file_lock_factory.php  (implementation method and debug message) lib/classes/lock/mysql_lock_factory.php  (implementation method and debug message) lib/classes/lock/lock.php  (used in extend() which will be also deprecated) Test 3 (extend()) Using the terminal go to the root folder of your moodle instance. Do a grep for 'extend' grep -R -e "[[:blank:]]extend(" -e ">extend(" --include \*.php --include \*.txt   Confirm that the only results are in: lib/upgrade.txt (notes about the deprecated extend()) lib/classes/lock/lock.php  (method declaration and debug message)
    • 3
    • Activity Sprint 10, 4.0 holding pattern, 4.0 holding pattern 2

    Description

      If a lock type supports_recursion() then the locks behave very differently to when they don't.

      Yet despite this not a single place in core actually calls for supports_recursion(), and if it did then it would have to do a code fork to work around the different behaviors. This feels like an architectural mistake in the design of the lock api, all lock implementations should behave identically so that calling code doesn't need to worry about things like this.

      Given that the only place that leverages this is the unit tests, it is clear no one wants or needs it or is using this. I've had a bit of a quick search on github and in the wild for 3rd party uses and couldn't find any.

      It's also trivial to workaround in the lock types that do support recursion to bring their behavior back in line to the locks which don't, as they already internally store a list of open locks for the current request and could just reject the second lock attempt.

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          has a non-specific relationship to

          Task - A task that needs to be completed. Tasks usually refer to work that must be done outside the product. MDL-69653 Final deprecation of extend_lock()

          • Minor - Minor loss of function where workaround is possible
          • Closed
          has been marked as being related by

          Improvement - An enhancement to an existing Moodle feature. MDL-67022 Pull moodle-local_redislock into core ?

          • Minor - Minor loss of function where workaround is possible
          • Open

          Activity

            People

              Geshoski Mihail Geshoski
              brendanheywood Brendan Heywood
              Mathew May Mathew May
              Andrew Lyons Andrew Lyons
              Janelle Barcega Janelle Barcega
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              2 Vote for this issue
              Watchers:
              11 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved:
                9/Nov/20

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