329 lines
11 KiB
Python
329 lines
11 KiB
Python
# Copyright (c) 2022, Frappe Technologies Pvt. Ltd. and Contributors
|
|
# License: MIT. See LICENSE
|
|
|
|
# Tree (Hierarchical) Nested Set Model (nsm)
|
|
#
|
|
# To use the nested set model,
|
|
# use the following pattern
|
|
# 1. name your parent field as "parent_item_group" if not have a property nsm_parent_field as your field name in the document class
|
|
# 2. have a field called "old_parent" in your fields list - this identifies whether the parent has been changed
|
|
# 3. call update_nsm(doc_obj) in the on_upate method
|
|
|
|
# ------------------------------------------
|
|
from typing import Iterator
|
|
|
|
import frappe
|
|
from frappe import _
|
|
from frappe.model.document import Document
|
|
from frappe.query_builder import DocType, Order
|
|
from frappe.query_builder.functions import Coalesce, Max
|
|
from frappe.query_builder.utils import DocType
|
|
|
|
|
|
class NestedSetRecursionError(frappe.ValidationError): pass
|
|
class NestedSetMultipleRootsError(frappe.ValidationError): pass
|
|
class NestedSetChildExistsError(frappe.ValidationError): pass
|
|
class NestedSetInvalidMergeError(frappe.ValidationError): pass
|
|
|
|
# called in the on_update method
|
|
def update_nsm(doc):
|
|
# get fields, data from the DocType
|
|
old_parent_field = 'old_parent'
|
|
parent_field = "parent_" + frappe.scrub(doc.doctype)
|
|
|
|
if hasattr(doc,'nsm_parent_field'):
|
|
parent_field = doc.nsm_parent_field
|
|
if hasattr(doc,'nsm_oldparent_field'):
|
|
old_parent_field = doc.nsm_oldparent_field
|
|
|
|
parent, old_parent = doc.get(parent_field) or None, doc.get(old_parent_field) or None
|
|
|
|
# has parent changed (?) or parent is None (root)
|
|
if not doc.lft and not doc.rgt:
|
|
update_add_node(doc, parent or '', parent_field)
|
|
elif old_parent != parent:
|
|
update_move_node(doc, parent_field)
|
|
|
|
# set old parent
|
|
doc.set(old_parent_field, parent)
|
|
frappe.db.set_value(doc.doctype, doc.name, old_parent_field, parent or '', update_modified=False)
|
|
|
|
doc.reload()
|
|
|
|
def update_add_node(doc, parent, parent_field):
|
|
"""
|
|
insert a new node
|
|
"""
|
|
doctype = doc.doctype
|
|
name = doc.name
|
|
Table = DocType(doctype)
|
|
|
|
# get the last sibling of the parent
|
|
if parent:
|
|
left, right = frappe.db.get_value(doctype, {"name": parent}, ["lft", "rgt"], for_update=True)
|
|
validate_loop(doc.doctype, doc.name, left, right)
|
|
else: # root
|
|
right = frappe.qb.from_(Table).select(
|
|
Coalesce(Max(Table.rgt), 0) + 1
|
|
).where(Coalesce(Table[parent_field], "") == "").run(pluck=True)[0]
|
|
|
|
right = right or 1
|
|
|
|
# update all on the right
|
|
frappe.qb.update(Table).set(Table.rgt, Table.rgt + 2).where(Table.rgt >= right).run()
|
|
frappe.qb.update(Table).set(Table.lft, Table.lft + 2).where(Table.lft >= right).run()
|
|
|
|
if frappe.qb.from_(Table).select("*").where((Table.lft == right) | (Table.rgt == right + 1)).run():
|
|
frappe.throw(_("Nested set error. Please contact the Administrator."))
|
|
|
|
# update index of new node
|
|
frappe.qb.update(Table).set(Table.lft, right).set(Table.rgt, right + 1).where(Table.name == name).run()
|
|
return right
|
|
|
|
|
|
def update_move_node(doc: Document, parent_field: str):
|
|
parent: str = doc.get(parent_field)
|
|
Table = DocType(doc.doctype)
|
|
|
|
if parent:
|
|
new_parent = frappe.qb.from_(Table).select(
|
|
Table.lft, Table.rgt
|
|
).where(Table.name == parent).for_update().run(as_dict=True)[0]
|
|
|
|
validate_loop(doc.doctype, doc.name, new_parent.lft, new_parent.rgt)
|
|
|
|
# move to dark side
|
|
frappe.qb.update(Table).set(Table.lft, - Table.lft).set(Table.rgt, - Table.rgt).where(
|
|
(Table.lft >= doc.lft) & (Table.rgt <= doc.rgt)
|
|
).run()
|
|
|
|
# shift left
|
|
diff = doc.rgt - doc.lft + 1
|
|
frappe.qb.update(Table).set(Table.lft, Table.lft - diff).set(Table.rgt, Table.rgt - diff).where(
|
|
Table.lft > doc.rgt
|
|
).run()
|
|
|
|
# shift left rgts of ancestors whose only rgts must shift
|
|
frappe.qb.update(Table).set(Table.rgt, Table.rgt - diff).where(
|
|
(Table.lft < doc.lft) & (Table.rgt > doc.rgt)
|
|
).run()
|
|
|
|
if parent:
|
|
# set parent lft, rgt
|
|
frappe.qb.update(Table).set(Table.rgt, Table.rgt + diff).where(Table.name == parent).run()
|
|
|
|
# shift right at new parent
|
|
frappe.qb.update(Table).set(Table.lft, Table.lft + diff).set(Table.rgt, Table.rgt + diff).where(
|
|
(Table.lft >= new_parent.lft) & (Table.lft <= new_parent.rgt)
|
|
).run()
|
|
|
|
frappe.qb.update(Table).set(Table.lft, Table.lft + diff).set(Table.rgt, Table.rgt + diff).where(
|
|
Table.lft > new_parent.rgt
|
|
).run()
|
|
|
|
# shift right rgts of ancestors whose only rgts must shift
|
|
frappe.qb.update(Table).set(Table.rgt, Table.rgt + diff).where(
|
|
(Table.lft < new_parent.lft) & (Table.rgt > new_parent.rgt)
|
|
).run()
|
|
|
|
new_diff = new_parent.rgt - doc.lft
|
|
else:
|
|
# new root
|
|
max_rgt = frappe.qb.from_(Table).select(Max(Table.rgt)).run(pluck=True)[0]
|
|
new_diff = max_rgt + 1 - doc.lft
|
|
|
|
# bring back from dark side
|
|
frappe.qb.update(Table).set(
|
|
Table.lft, -Table.lft + new_diff
|
|
).set(
|
|
Table.rgt, -Table.rgt + new_diff
|
|
).where(Table.lft < 0).run()
|
|
|
|
|
|
@frappe.whitelist()
|
|
def rebuild_tree(doctype, parent_field):
|
|
"""
|
|
call rebuild_node for all root nodes
|
|
"""
|
|
|
|
# Check for perm if called from client-side
|
|
if frappe.request and frappe.local.form_dict.cmd == 'rebuild_tree':
|
|
frappe.only_for('System Manager')
|
|
|
|
meta = frappe.get_meta(doctype)
|
|
if not meta.has_field("lft") or not meta.has_field("rgt"):
|
|
frappe.throw(_("Rebuilding of tree is not supported for {}").format(frappe.bold(doctype)),
|
|
title=_("Invalid Action"))
|
|
|
|
# get all roots
|
|
right = 1
|
|
table = DocType(doctype)
|
|
column = getattr(table, parent_field)
|
|
result = (
|
|
frappe.qb.from_(table)
|
|
.where(
|
|
(column == "") | (column.isnull())
|
|
)
|
|
.orderby(table.name, order=Order.asc)
|
|
.select(table.name)
|
|
).run()
|
|
|
|
frappe.db.auto_commit_on_many_writes = 1
|
|
|
|
for r in result:
|
|
right = rebuild_node(doctype, r[0], right, parent_field)
|
|
|
|
frappe.db.auto_commit_on_many_writes = 0
|
|
|
|
def rebuild_node(doctype, parent, left, parent_field):
|
|
"""
|
|
reset lft, rgt and recursive call for all children
|
|
"""
|
|
# the right value of this node is the left value + 1
|
|
right = left+1
|
|
|
|
# get all children of this node
|
|
table = DocType(doctype)
|
|
column = getattr(table, parent_field)
|
|
|
|
result = (
|
|
frappe.qb.from_(table).where(column == parent).select(table.name)
|
|
).run()
|
|
|
|
for r in result:
|
|
right = rebuild_node(doctype, r[0], right, parent_field)
|
|
|
|
# we've got the left value, and now that we've processed
|
|
# the children of this node we also know the right value
|
|
frappe.db.set_value(doctype, parent, {"lft": left, "rgt": right}, for_update=False, update_modified=False)
|
|
|
|
#return the right value of this node + 1
|
|
return right+1
|
|
|
|
|
|
def validate_loop(doctype, name, lft, rgt):
|
|
"""check if item not an ancestor (loop)"""
|
|
if name in frappe.get_all(doctype, filters={"lft": ["<=", lft], "rgt": [">=", rgt]}, pluck="name"):
|
|
frappe.throw(_("Item cannot be added to its own descendents"), NestedSetRecursionError)
|
|
|
|
|
|
class NestedSet(Document):
|
|
def __setup__(self):
|
|
if self.meta.get("nsm_parent_field"):
|
|
self.nsm_parent_field = self.meta.nsm_parent_field
|
|
|
|
def on_update(self):
|
|
update_nsm(self)
|
|
self.validate_ledger()
|
|
|
|
def on_trash(self, allow_root_deletion=False):
|
|
if not getattr(self, 'nsm_parent_field', None):
|
|
self.nsm_parent_field = frappe.scrub(self.doctype) + "_parent"
|
|
|
|
parent = self.get(self.nsm_parent_field)
|
|
if not parent and not allow_root_deletion:
|
|
frappe.throw(_("Root {0} cannot be deleted").format(_(self.doctype)))
|
|
|
|
# cannot delete non-empty group
|
|
self.validate_if_child_exists()
|
|
|
|
self.set(self.nsm_parent_field, "")
|
|
|
|
try:
|
|
update_nsm(self)
|
|
except frappe.DoesNotExistError:
|
|
if self.flags.on_rollback:
|
|
frappe.message_log.pop()
|
|
else:
|
|
raise
|
|
|
|
def validate_if_child_exists(self):
|
|
has_children = frappe.db.count(self.doctype, filters={self.nsm_parent_field: self.name})
|
|
if has_children:
|
|
frappe.throw(_("Cannot delete {0} as it has child nodes").format(self.name), NestedSetChildExistsError)
|
|
|
|
def before_rename(self, olddn, newdn, merge=False, group_fname="is_group"):
|
|
if merge and hasattr(self, group_fname):
|
|
is_group = frappe.db.get_value(self.doctype, newdn, group_fname)
|
|
if self.get(group_fname) != is_group:
|
|
frappe.throw(_("Merging is only possible between Group-to-Group or Leaf Node-to-Leaf Node"), NestedSetInvalidMergeError)
|
|
|
|
def after_rename(self, olddn, newdn, merge=False):
|
|
if not self.nsm_parent_field:
|
|
parent_field = "parent_" + self.doctype.replace(" ", "_").lower()
|
|
else:
|
|
parent_field = self.nsm_parent_field
|
|
|
|
# set old_parent for children
|
|
frappe.db.set_value(self.doctype, {"old_parent": newdn}, {parent_field: newdn}, update_modified=False, for_update=False)
|
|
|
|
if merge:
|
|
rebuild_tree(self.doctype, parent_field)
|
|
|
|
def validate_one_root(self):
|
|
if not self.get(self.nsm_parent_field):
|
|
if self.get_root_node_count() > 1:
|
|
frappe.throw(_("""Multiple root nodes not allowed."""), NestedSetMultipleRootsError)
|
|
|
|
def get_root_node_count(self):
|
|
return frappe.db.count(self.doctype, {
|
|
self.nsm_parent_field: ''
|
|
})
|
|
|
|
def validate_ledger(self, group_identifier="is_group"):
|
|
if hasattr(self, group_identifier) and not bool(self.get(group_identifier)):
|
|
if frappe.get_all(self.doctype, {self.nsm_parent_field: self.name, "docstatus": ("!=", 2)}):
|
|
frappe.throw(_("{0} {1} cannot be a leaf node as it has children").format(_(self.doctype), self.name))
|
|
|
|
def get_ancestors(self):
|
|
return get_ancestors_of(self.doctype, self.name)
|
|
|
|
def get_parent(self) -> "NestedSet":
|
|
"""Return the parent Document."""
|
|
parent_name = self.get(self.nsm_parent_field)
|
|
if parent_name:
|
|
return frappe.get_doc(self.doctype, parent_name)
|
|
|
|
def get_children(self) -> Iterator["NestedSet"]:
|
|
"""Return a generator that yields child Documents."""
|
|
child_names = frappe.get_list(self.doctype, filters={self.nsm_parent_field: self.name}, pluck="name")
|
|
for name in child_names:
|
|
yield frappe.get_doc(self.doctype, name)
|
|
|
|
|
|
def get_root_of(doctype):
|
|
"""Get root element of a DocType with a tree structure"""
|
|
from frappe.query_builder.functions import Count
|
|
from frappe.query_builder.terms import subqry
|
|
|
|
Table = DocType(doctype)
|
|
t1 = Table.as_("t1")
|
|
t2 = Table.as_("t2")
|
|
|
|
subq = frappe.qb.from_(t2).select(Count("*")).where(
|
|
(t2.lft < t1.lft) & (t2.rgt > t1.rgt)
|
|
)
|
|
result = frappe.qb.from_(t1).select(t1.name).where(
|
|
(subqry(subq) == 0) & (t1.rgt > t1.lft)
|
|
).run()
|
|
|
|
return result[0][0] if result else None
|
|
|
|
def get_ancestors_of(doctype, name, order_by="lft desc", limit=None):
|
|
"""Get ancestor elements of a DocType with a tree structure"""
|
|
lft, rgt = frappe.db.get_value(doctype, name, ["lft", "rgt"])
|
|
|
|
result = [d["name"] for d in frappe.db.get_all(doctype, {"lft": ["<", lft], "rgt": [">", rgt]},
|
|
"name", order_by=order_by, limit_page_length=limit)]
|
|
|
|
return result or []
|
|
|
|
def get_descendants_of(doctype, name, order_by="lft desc", limit=None,
|
|
ignore_permissions=False):
|
|
'''Return descendants of the current record'''
|
|
lft, rgt = frappe.db.get_value(doctype, name, ['lft', 'rgt'])
|
|
|
|
result = [d["name"] for d in frappe.db.get_list(doctype, {"lft": [">", lft], "rgt": ["<", rgt]},
|
|
"name", order_by=order_by, limit_page_length=limit, ignore_permissions=ignore_permissions)]
|
|
|
|
return result or []
|