feat: Create NestedSet doctypes via configuration

frappe/core/doctype/doctype/boilerplate/controller._py

@@ -4,7 +4,7 @@
 
 from __future__ import unicode_literals
 # import frappe
-from frappe.model.document import Document
+{base_class_import}
 
-class {classname}(Document):
+class {classname}({base_class}):
 	pass

frappe/core/doctype/doctype/doctype.json

@@ -12,6 +12,7 @@
   "is_submittable",
   "istable",
   "issingle",
+  "is_tree",
   "editable_grid",
   "quick_entry",
   "cb01",
@@ -30,6 +31,7 @@
   "form_settings_section",
   "image_field",
   "timeline_field",
+  "nsm_parent_field",
   "max_attachments",
   "column_break_23",
   "hide_toolbar",
@@ -438,11 +440,23 @@
    "fieldtype": "Select",
    "label": "Database Engine",
    "options": "InnoDB\nMyISAM"
+  },
+  {
+   "default": "0",
+   "description": "Tree structures are implemented using Nested Set",
+   "fieldname": "is_tree",
+   "fieldtype": "Check",
+   "label": "Is Tree"
+  },
+  {
+   "fieldname": "nsm_parent_field",
+   "fieldtype": "Data",
+   "label": "Parent Field (Tree)"
   }
  ],
  "icon": "fa fa-bolt",
  "idx": 6,
- "modified": "2019-07-04 23:23:17.174960",
+ "modified": "2019-09-02 05:51:29.411525",
  "modified_by": "Administrator",
  "module": "Core",
  "name": "DocType",
@@ -475,4 +489,4 @@
  "sort_field": "modified",
  "sort_order": "DESC",
  "track_changes": 1
-}
+}

frappe/core/doctype/doctype/doctype.py

@@ -84,6 +84,7 @@ class DocType(Document):
 
 		self.make_amendable()
 		self.make_repeatable()
+		self.validate_nestedset()
 		self.validate_website()
 
 		if not self.is_new():
@@ -581,6 +582,64 @@ class DocType(Document):
 				df = dict(fieldname='auto_repeat', label='Auto Repeat', fieldtype='Link', options='Auto Repeat', insert_after=insert_after, read_only=1, no_copy=1, print_hide=1)
 				create_custom_field(self.name, df)
 
+	def validate_nestedset(self):
+		if not self.is_tree:
+			return
+		self.add_nestedset_fields()
+		# set field as mandatory
+		field = self.meta.get_field('nsm_parent_field')
+		field.reqd = 1
+		# check if field is valid
+		fieldnames = [df.fieldname for df in self.fields]
+		if self.nsm_parent_field and self.nsm_parent_field not in fieldnames:
+			frappe.throw(_("Parent Field must be a valid fieldname"), InvalidFieldNameError)
+
+	def add_nestedset_fields(self):
+		"""If is_tree is set, add parent_field, lft, rgt, is_group fields."""
+		fieldnames = [df.fieldname for df in self.fields]
+		if 'lft' in fieldnames:
+			return
+
+		self.append("fields", {
+			"label": "Left",
+			"fieldtype": "Int",
+			"fieldname": "lft",
+			"read_only": 1,
+			"hidden": 1,
+			"no_copy": 1
+		})
+
+		self.append("fields", {
+			"label": "Right",
+			"fieldtype": "Int",
+			"fieldname": "rgt",
+			"read_only": 1,
+			"hidden": 1,
+			"no_copy": 1
+		})
+
+		self.append("fields", {
+			"label": "Is Group",
+			"fieldtype": "Check",
+			"fieldname": "is_group"
+		})
+		self.append("fields", {
+			"label": "Old Parent",
+			"fieldtype": "Link",
+			"options": self.name,
+			"fieldname": "old_parent"
+		})
+
+		parent_field_label = "Parent {}".format(self.name)
+		parent_field_name = frappe.scrub(parent_field_label)
+		self.append("fields", {
+			"label": parent_field_label,
+			"fieldtype": "Link",
+			"options": self.name,
+			"fieldname": parent_field_name
+		})
+		self.nsm_parent_field = parent_field_name
+
 
 	def get_max_idx(self):
 		"""Returns the highest `idx`"""

frappe/model/base_document.py

@@ -30,14 +30,15 @@ def get_controller(doctype):
 
 	:param doctype: DocType name as string."""
 	from frappe.model.document import Document
+	from frappe.utils.nestedset import NestedSet
 	global _classes
 
 	if not doctype in _classes:
-		module_name, custom = frappe.db.get_value("DocType", doctype, ("module", "custom"), cache=True) \
-			or ["Core", False]
+		module_name, custom, is_tree = frappe.db.get_value("DocType", doctype, ("module", "custom", "is_tree"), cache=True) \
+			or ["Core", False, False]
 
 		if custom:
-			_class = Document
+			_class = NestedSet if is_tree else Document
 		else:
 			module = load_doctype_module(doctype, module_name)
 			classname = doctype.replace(" ", "").replace("-", "")

frappe/modules/utils.py

@@ -240,6 +240,12 @@ def make_boilerplate(template, doc, opts=None):
 		if not opts:
 			opts = {}
 
+		base_class = 'Document'
+		base_class_import = 'from frappe.model.document import Document'
+		if doc.is_tree:
+			base_class = 'NestedSet'
+			base_class_import = 'from frappe.utils.nestedset import NestedSet'
+
 		with open(target_file_path, 'w') as target:
 			with open(os.path.join(get_module_path("core"), "doctype", scrub(doc.doctype),
 				"boilerplate", template), 'r') as source:
@@ -248,5 +254,7 @@ def make_boilerplate(template, doc, opts=None):
 						app_publisher=app_publisher,
 						year=frappe.utils.nowdate()[:4],
 						classname=doc.name.replace(" ", ""),
+						base_class_import=base_class_import,
+						base_class=base_class,
 						doctype=doc.name, **opts)
 				))

frappe/public/js/frappe/list/list_sidebar.js

@@ -62,7 +62,7 @@ frappe.views.ListSidebar = class ListSidebar {
 			show_list_link = true;
 		}
 
-		if (frappe.treeview_settings[this.doctype]) {
+		if (frappe.treeview_settings[this.doctype] || frappe.get_meta(this.doctype).is_tree) {
 			this.sidebar.find(".tree-link").removeClass("hide");
 		}
 

frappe/utils/nestedset.py

@@ -183,6 +183,10 @@ def validate_loop(doctype, name, lft, rgt):
 		frappe.throw(_("Item cannot be added to its own descendents"), NestedSetRecursionError)
 
 class NestedSet(Document):
+	def __setup__(self):
+		if self.meta.nsm_parent_field:
+			self.nsm_parent_field = self.meta.nsm_parent_field
+
 	def on_update(self):
 		update_nsm(self)
 		self.validate_ledger()