Frappe_Claude_Skill_Package frappe-syntax-doctypes

install
source · Clone the upstream repo
git clone https://github.com/OpenAEC-Foundation/Frappe_Claude_Skill_Package
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/OpenAEC-Foundation/Frappe_Claude_Skill_Package "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/source/syntax/frappe-syntax-doctypes" ~/.claude/skills/openaec-foundation-frappe-claude-skill-package-frappe-syntax-doctypes && rm -rf "$T"
manifest: skills/source/syntax/frappe-syntax-doctypes/SKILL.md
source content

DocType JSON Design

DocTypes are the foundation of every Frappe application. A DocType defines both the data model (database schema) and the view (form layout). ALWAYS design DocTypes before writing any controller logic.

Quick Reference

DocType JSON Top-Level Properties

PropertyTypePurpose
name
strDocType identifier (singular, e.g. "Sales Invoice")
module
strApp module this DocType belongs to
is_submittable
boolEnables Draft -> Submitted -> Cancelled workflow
is_tree
boolEnables NestedSet hierarchy (lft/rgt columns)
is_virtual
boolNo database table; data from custom backend
issingle
boolSingle-instance settings document
istable
boolChild table DocType (embedded in parent)
is_calendar_and_gantt
boolEnables calendar/gantt views
track_changes
boolStores version history on every save
track_seen
boolTracks which users viewed the document
track_views
boolCounts total document views
allow_rename
boolPermits renaming after creation
allow_copy
boolEnables "Duplicate" action
allow_import
boolEnables Data Import for this DocType
naming_rule
strNaming method selector (see Naming section)
autoname
strNaming pattern string
title_field
strField used as display title
search_fields
strComma-separated fields for search results
show_title_field_in_link
boolDisplay title instead of name in Link fields
image_field
strField containing image for avatar display
sort_field
strDefault sort column
sort_order
str"ASC" or "DESC"
default_print_format
strPrint Format name
max_attachments
intAttachment limit

Common Fieldtypes (Quick Lookup)

FieldtypeStoresDB Column
DataText up to 140 charsVARCHAR(140)
LinkReference to another DocTypeVARCHAR(140)
Dynamic LinkReference to any DocTypeVARCHAR(140)
SelectSingle choice from optionsVARCHAR(140)
TableChild table rowsSeparate table
Table MultiSelectMulti-select link rowsSeparate table
CheckBoolean 0/1TINYINT
IntWhole numberINT
FloatDecimal (9 places)DECIMAL
CurrencyMoney value (6 decimals)DECIMAL
DateCalendar dateDATE
DatetimeDate + timeDATETIME
Text EditorRich text (HTML)LONGTEXT
AttachFile referenceVARCHAR(140)
Small TextShort multi-line textTEXT
Long TextUnlimited textLONGTEXT

Full fieldtype reference with all 35+ types: references/fieldtypes.md

Essential Field Properties

PropertyTypePurpose
reqd
boolField is mandatory
unique
boolDatabase UNIQUE constraint
search_index
boolDatabase INDEX for faster queries
in_list_view
boolShow in list view columns
in_standard_filter
boolShow as filter in list view
in_preview
boolShow in document preview
allow_on_submit
boolEditable after submission
read_only
boolNot editable by user
hidden
boolNot visible on form
depends_on
strVisibility condition (e.g.
eval:doc.status=="Active"
)
mandatory_depends_on
strConditional mandatory
read_only_depends_on
strConditional read-only
fetch_from
strAuto-populate from linked doc (e.g.
customer.customer_name
)
fetch_if_empty
boolOnly fetch when field is empty
options
strFieldtype-specific (DocType name, select options, etc.)
default
strDefault value (supports
__user
,
Today
, etc.)
description
strHelp text below field
collapsible
boolSection starts collapsed (Section Break only)

Decision Tree: Which DocType Type?

Need to store data?
├─ YES: Need multiple records?
│  ├─ YES: Need submit/cancel workflow?
│  │  ├─ YES → Standard DocType + is_submittable=1
│  │  └─ NO: Need hierarchy/tree?
│  │     ├─ YES → Tree DocType (is_tree=1)
│  │     └─ NO: Embedded in parent?
│  │        ├─ YES → Child DocType (istable=1)
│  │        └─ NO → Standard DocType
│  └─ NO: Single config/settings → Single DocType (issingle=1)
└─ NO: Data from external source → Virtual DocType (is_virtual=1)

Naming Rules

ALWAYS set

naming_rule
on the DocType. The
autoname
field holds the pattern.

naming_rule Valueautoname PatternExample Output
Set by User(empty)User types name manually
Autoincrement(empty)
1
,
2
,
3
By Fieldname
field:{fieldname}
Value of that field
By Naming Series
naming_series:
INV-2024-00001
(from series field)
Expression
PRE-.#####
PRE-00001
,
PRE-00002
Expression (Old Style)
{prefix}-{YYYY}-{#####}
INV-2024-00001
Random
hash
Random 10-char string
UUID(empty)
550e8400-e29b-...
By Script(custom)Controller
autoname()
decides

NEVER use Autoincrement in production -- gaps appear when records are deleted. Use Expression or Naming Series instead.

Full naming reference: references/naming.md

Child Table Design

A Child DocType is a DocType with

istable=1
. It ALWAYS belongs to a parent.

Parent side -- add a field with:

  • fieldtype
    :
    Table
    (or
    Table MultiSelect
    )
  • options
    : Child DocType name

Child records automatically get:

  • parent
    -- name of the parent document
  • parenttype
    -- DocType of the parent
  • parentfield
    -- fieldname of the Table field in parent
  • idx
    -- row order (1-based)
# Adding child rows programmatically
doc = frappe.get_doc("Sales Invoice", "INV-001")
doc.append("items", {
    "item_code": "ITEM-001",
    "qty": 5,
    "rate": 100.0
})
doc.save()

NEVER create a Child DocType without

istable=1
. NEVER reference a non-child DocType in a Table field.

Table vs Table MultiSelect

AspectTableTable MultiSelect
UIFull editable grid with "Add Row"Tag-style picker, no "Add Row"
Child DocTypeFull child with many fieldsTypically 1 Link field only
Use caseLine items, detail rowsMulti-select references

Single DocType (Settings Pattern)

Set

issingle=1
. Data is stored in
tabSingles
as key-value pairs, NOT in a dedicated table.

# Access Single DocType
settings = frappe.get_single("My Settings")
value = settings.some_field

# Or directly
value = frappe.db.get_single_value("My Settings", "some_field")
  • NEVER expect a list view for Single DocTypes -- they have exactly one instance.
  • ALWAYS use for app-wide configuration (API keys, default values, feature toggles).

Tree DocType (NestedSet)

Set

is_tree=1
. Frappe adds
lft
,
rgt
,
parent_{doctype_fieldname}
,
old_parent
columns automatically.

  • ALWAYS define a
    parent_field
    in the DocType JSON (e.g.
    parent_account
    for Chart of Accounts).
  • The NestedSet model uses
    lft
    /
    rgt
    integers for efficient subtree queries.
  • NEVER manually edit
    lft
    /
    rgt
    values. Use
    frappe.utils.nestedset.rebuild_tree()
    if corrupted.
# Get all descendants
descendants = frappe.get_all("Account",
    filters={"lft": [">", node.lft], "rgt": ["<", node.rgt]})

# Get ancestors (path to root)
ancestors = frappe.get_all("Account",
    filters={"lft": ["<", node.lft], "rgt": [">", node.rgt]},
    order_by="lft asc")

Virtual DocType

Set

is_virtual=1
. No database table is created. ALWAYS implement these controller methods:

class MyVirtualDoc(Document):
    def db_insert(self, *args, **kwargs):
        # Persist to your custom backend
        pass

    def load_from_db(self):
        # Load document data from your source
        pass

    def db_update(self, *args, **kwargs):
        # Update in your custom backend
        pass

    def delete(self):
        # Remove from your custom backend
        pass

    @staticmethod
    def get_list(args):
        # Return list of documents
        pass

    @staticmethod
    def get_count(args):
        # Return total count
        pass

    @staticmethod
    def get_stats(args):
        # Return statistics
        pass

NEVER use

frappe.db.*
calls for Virtual DocType data -- they only work with the site database, not your custom backend.

Customization APIs

Custom Fields (Programmatic)

from frappe.custom.doctype.custom_field.custom_field import create_custom_fields

# Dict format: {DocType: [field_dicts]}
create_custom_fields({
    "Sales Invoice": [
        dict(fieldname="custom_tracking", label="Tracking ID",
             fieldtype="Data", insert_after="naming_series")
    ],
    "Purchase Order": [
        dict(fieldname="custom_vendor_ref", label="Vendor Ref",
             fieldtype="Data", insert_after="supplier")
    ]
}, update=True)

Property Setter (Programmatic)

from frappe.custom.doctype.property_setter.property_setter import make_property_setter

# Change a field property on an existing DocType
make_property_setter("Sales Invoice", "customer", "reqd", 1, "Check")
make_property_setter("Sales Invoice", "posting_date", "default", "Today", "Text")

Full customization reference: references/customization.md

Data Masking (v16+)

Fields with

mask=1
hide sensitive values from users without
mask
permission at the field's
permlevel
. The server replaces values with patterns like
XXXXXXXX
before sending to the client. Administrator ALWAYS sees unmasked values.

{ "fieldname": "phone", "fieldtype": "Data", "options": "Phone", "mask": 1, "permlevel": 1 }

Full masking reference: references/data-masking.md

Python Type Stubs

Frappe auto-generates type annotations in controller files via

TypeExporter
. Fields get
DF.*
types inside a
TYPE_CHECKING
guard:

if TYPE_CHECKING:
    from frappe.types import DF
    customer: DF.Link
    items: DF.Table[SalesInvoiceItem]
    status: DF.Literal["Draft", "Submitted", "Paid"]

NEVER modify code between

# begin: auto-generated types
and
# end: auto-generated types
.

Full type stubs reference: references/type-stubs.md

Critical Rules

  1. ALWAYS name DocTypes in singular form ("Sales Invoice", not "Sales Invoices").
  2. ALWAYS use the
    tab
    prefix mentally -- the DB table is
    tabSales Invoice
    .
  3. NEVER exceed 140 characters for Data/Link/Select field values.
  4. ALWAYS set
    search_index=1
    on fields used in frequent filters or
    get_list
    calls.
  5. ALWAYS set
    in_standard_filter=1
    on fields users frequently filter by.
  6. NEVER use
    allow_on_submit=1
    on child table fields that affect calculations without recalculating totals.
  7. ALWAYS set
    fetch_if_empty=1
    alongside
    fetch_from
    unless you want to overwrite user edits.
  8. NEVER define
    depends_on
    with raw Python -- use
    eval:doc.fieldname == "value"
    syntax.

See Also