fe26c542b7
Moved before/after tasks in Requests as hooks for: - monitor - rate_limiter - recorder Moved before/after tasks in Jobs as hooks for: - monitor - releasing document locks
70 lines
1.6 KiB
Python
70 lines
1.6 KiB
Python
# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
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# License: MIT. See LICENSE
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"""Utils for inter-process synchronization using file-locks.
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This file implements a "weak" form lock which is not suitable for synchroniztion. This is only used
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for document locking for queue_action.
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Use `frappe.utils.synchroniztion.filelock` for process synchroniztion.
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"""
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import os
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from time import time
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import frappe
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from frappe.utils import get_site_path, touch_file
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LOCKS_DIR = "locks"
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class LockTimeoutError(Exception):
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pass
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def create_lock(name):
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"""Creates a file in the /locks folder by the given name.
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Note: This is a "weak lock" and is prone to race conditions. Do not use this lock for small
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sections of code that execute immediately.
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This is primarily use for locking documents for background submission.
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"""
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lock_path = get_lock_path(name)
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if not check_lock(lock_path):
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return touch_file(lock_path)
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else:
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return False
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def lock_exists(name):
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"""Returns True if lock of the given name exists"""
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return os.path.exists(get_lock_path(name))
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def check_lock(path, timeout=600):
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if not os.path.exists(path):
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return False
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if time() - os.path.getmtime(path) > timeout:
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raise LockTimeoutError(path)
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return True
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def delete_lock(name):
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lock_path = get_lock_path(name)
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try:
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os.remove(lock_path)
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except OSError:
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pass
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return True
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def get_lock_path(name):
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name = name.lower()
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lock_path = get_site_path(LOCKS_DIR, name + ".lock")
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return lock_path
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def release_document_locks():
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"""Unlocks all documents that were locked by the current context."""
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for doc in frappe.local.locked_documents:
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doc.unlock()
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