Enums & Types Reference

All enumerations and canonical types used in DataSurface contracts and attributes.

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CrudDto (Flags)

Field participation in DTO shapes and query capabilities. Combinable via bitwise OR.

Flag	Value	Description
None	0	Not included in any shape
Read	1	Included in GET responses
Create	2	Accepted in POST body
Update	4	Accepted in PATCH body
Filter	8	Can use filter[field]=value
Sort	16	Can use sort=field

Common combinations:

Pattern	Flags	Meaning
Full lifecycle	Read | Create | Update	Read, create, and update
Read-only	Read	Only in responses
Queryable	Read | Filter | Sort	Readable and queryable
Full	Read | Create | Update | Filter | Sort	Everything enabled

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CrudOperation

CRUD operation identifiers used in authorization, hooks, overrides, and contracts.

Value	Description
List	GET collection (paginated list)
Get	GET single item by ID
Create	POST new item
Update	PATCH / PUT existing item
Delete	DELETE item

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StorageBackend

Backend storage types for resources.

Value	Description
EfCore	Entity Framework Core — static, compile-time entities
DynamicJson	JSON document storage — flexible, schema-free
DynamicEav	Entity-Attribute-Value storage — sparse data
DynamicHybrid	Hybrid — structured columns with JSON overflow

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FieldType

Canonical field types mapping CLR types to contract representations.

Value	C# Types	JSON Type
String	string, char, TimeOnly, TimeSpan, byte[] (base64)	string
Int32	int, short, byte, sbyte, ushort	integer (format: int32)
Int64	long, uint, ulong	integer (format: int64)
Decimal	decimal, double, float	number
Boolean	bool	boolean
DateTime	DateTime, DateTimeOffset, DateOnly	string (format: date-time)
Guid	Guid	string (format: uuid)
Json	Other complex types (fallback)	object
Enum	Enum types	string
StringArray	string[]	array of string
IntArray	int[]	array of integer
GuidArray	Guid[]	array of string (format: uuid)
DecimalArray	decimal[]	array of number

Nullable CLR types (int?, DateTime?, …) map to the same FieldType with the field marked nullable.

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RelationKind

Relationship cardinality between resources.

Value	Description	Example
ManyToOne	FK reference to a single entity	Post.Author → User
OneToMany	Collection of dependent entities	User.Posts → Post[]
ManyToMany	Junction table relationship	Post.Tags → Tag[]
OneToOne	1:1 relationship	User.Profile → Profile

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RelationWriteMode

How relation writes are performed on create and update operations.

Value	Description	Request Format
None	No write support	(field not accepted)
ById	Write via FK field	{"authorId": 5}
ByIdList	Write via ID array	{"tagIds": [1, 2, 3]}
NestedDisabled	Nested objects explicitly rejected	Returns 400

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ConcurrencyMode

Optimistic concurrency control mechanism.

Value	Description
None	No concurrency control
RowVersion	byte[] row version token (EF Core concurrency token)
ETag	HTTP ETag-based token