Create the DocType

You build the Article DocType in the Desk UI. With developer mode on, Frappe
writes the definition to disk as files in your app, so the schema is tracked in
version control. A DocType gives you the database table, the form, the list view,
and a Python controller all at once. See the
DocTypes Overview for the bigger picture.

Open the DocType builder

Go to the DocType list using the search bar (awesomebar) and click + Add DocType:

http://library.localhost:8000/desk/doctype/new

Fill in the top section:

• Name: Article
• Module: Library Management
• Is Submittable: leave unchecked

Add fields

Use the DocType form builder to create the below fields. For each row set the Type, the
Label, and (where shown) the Options. The Name column (the
fieldname) is generated from the label, so Article Name becomes
article_name.

In the Select field's Options, put each choice on its own line:

Available
Issued

You can also create/edit these fields using the table in the Fields section.

This is the meta-data driven approach which differentiates Frappe Framework from traditional web development setups like Django.

Set the title field and naming

Open the Settings section (or the Naming section) of the DocType form:

• Title Field: article_name. This controls what shows as the document
  title in the form and lists.
• Naming Rule: choose By fieldname and set the field to article_name.
  The name (primary key) of each Article becomes its title. With this rule two
  articles cannot share the same name, which is fine for now.

See Naming for the other naming rules.

Save

Click Save. Frappe creates the tabArticle table and because developer mode is on, writes the DocType files to your app.

The generated files

The new files live under the module folder of your app:

apps/library_management/library_management/library_management/doctype/article/
├── __init__.py
├── article.json        # the schema: fields, naming, permissions
├── article.py          # the controller (Document subclass)
├── article.js          # the client script (form behaviour)
└── test_article.py     # a starter test

article.json is the source of truth for the schema. The relevant part looks
like this (trimmed):

{
  "doctype": "DocType",
  "name": "Article",
  "module": "Library Management",
  "title_field": "article_name",
  "autoname": "field:article_name",
  "fields": [
    {
      "fieldname": "article_name",
      "label": "Article Name",
      "fieldtype": "Data",
      "reqd": 1
    },
    { "fieldname": "author", "label": "Author", "fieldtype": "Data" },
    { "fieldname": "isbn", "label": "ISBN", "fieldtype": "Data" },
    {
      "fieldname": "status",
      "label": "Status",
      "fieldtype": "Select",
      "options": "Available\nIssued",
      "default": "Available"
    }
  ]
}

The generated article.py is a near-empty controller. You add logic to it on the
next page:

# Copyright (c) 2024, Your Company and contributors
# For license information, please see license.txt

import frappe
from frappe.model.document import Document


class Article(Document):
	pass

Create a record

Go to the Article list and add one so you have data to work with:

http://library.localhost:8000/desk/article/new

Enter an Article Name like The Pragmatic Programmer, an author, and save.

Create the other two DocTypes

You need two more DocTypes for the later pages. Create them the same way.

Library Member with fields:

Set its Naming Rule to By fieldname on full_name.

Library Transaction with fields:

A Link field stores the name of a record in another DocType and renders as
a searchable dropdown. Set Library Transaction's Naming Rule to
Autoincrement so each transaction gets a numeric name.

Add a couple of Library Transaction records with type Issue so the report on a
later page has something to show.

Continue to
Controllers and Business Logic.