schemadmt

Documentation

Overview

Package schema/dmt contains types and functions for dealing with the data model form of IPLD Schemas.

(DMT is short for "data model tree" -- see https://ipld.io/glossary/#dmt .)

As with anything that's IPLD data model, this data can be serialized or deserialized into a wide variety of codecs.

To contrast this package with some of its neighbors and with some various formats for the data this package describes: Schemas also have a DSL (a domain-specific language -- something that's meant to look nice, and be easy for humans to read and write), which are parsed by the `schema/dsl` package, and produce a DMT form (defined by and handled by this package). Schemas also have a compiled form, which is the in-memory structure that this library uses when working with them; this compiled form differs from the DMT because it can use pointers (and that includes cyclic pointers, which is something the DMT form cannot contain). We use the DMT form (this package) to produce the compiled form (which is the `schema` package).

Creating a Compiled schema either flows from DSL(text)->`schema/dsl`->`schema/dmt`->`schema`, or just (some codec, e.g. JSON or CBOR or etc)->`schema/dmt`->`schema`.

The `dmt.Schema` type describes the data found at the root of an IPLD Schema document. The `Compile` function turns such data into a `schema.TypeSystem` that is ready to be used. The `dmt.Prototype.Schema` value is a NodePrototype that can be used to handle IPLD Schemas in DMT form as regular IPLD Nodes.

Typically this package is imported aliased as "schemadmt", since "dmt" is a fairly generic term in the IPLD ecosystem (see https://ipld.io/glossary/#dmt ).

Many types in this package lack documentation directly on the type; generally, these are structs that match the IPLD schema-schema, and so you can find descriptions of them in documentation for the schema-schema.

Index

• Variables
• func Compile(ts *schema.TypeSystem, node *Schema) error
• type AnyScalar
• type EnumRepresentation
• type EnumRepresentation_Int
• type EnumRepresentation_String
• type InlineDefn
• type ListRepresentation
• type ListRepresentation_List
• type List__EnumMember
• type List__FieldName
• type List__TypeName
• type List__UnionMember
• type MapRepresentation
• type MapRepresentation_Listpairs
• type MapRepresentation_Map
• type MapRepresentation_Stringpairs
• type Map__FieldName__StructField
• type Map__FieldName__StructRepresentation_Map_FieldDetails
• type Map__HexString__TypeName
• type Map__String__TypeName
• type Map__String__UnionMember
• type Map__TypeName__Int
• type Map__TypeName__TypeDefn
• type Schema
  • func ConcatenateSchemas(a, b *Schema) *Schema
• type StructField
• type StructRepresentation
• type StructRepresentation_Listpairs
• type StructRepresentation_Map
• type StructRepresentation_Map_FieldDetails
• type StructRepresentation_Stringjoin
• type StructRepresentation_Stringpairs
• type StructRepresentation_Tuple
• type TypeDefn
• type TypeDefnAny
• type TypeDefnBool
• type TypeDefnBytes
• type TypeDefnCopy
• type TypeDefnEnum
• type TypeDefnFloat
• type TypeDefnInt
• type TypeDefnLink
• type TypeDefnList
• type TypeDefnMap
• type TypeDefnString
• type TypeDefnStruct
• type TypeDefnUnion
• type TypeDefnUnit
• type TypeNameOrInlineDefn
• type UnionMember
• type UnionMemberInlineDefn
• type UnionRepresentation
• type UnionRepresentation_BytesPrefix
• type UnionRepresentation_Envelope
• type UnionRepresentation_Inline
• type UnionRepresentation_Keyed
• type UnionRepresentation_Kinded
• type UnionRepresentation_StringPrefix
• type Unit

Variables

var Prototypes struct {
	Schema schema.TypedPrototype
}

Prototypes contains some schema.TypedPrototype values which match the IPLD schema-schema -- that is, the schema that describes IPLD schemas. These prototypes create an in-memory representation that is backed by structs in this package and bindnode.

var TypeSystem schema.TypeSystem

TypeSystem is a compiled equivalent of the IPLD schema-schema -- that is, the schema that describes IPLD schemas.

The IPLD schema-schema can be found at https://ipld.io/specs/schemas/schema-schema.ipldsch .

Functions

func Compile

func Compile(ts *schema.TypeSystem, node *Schema) error

Compile transforms a description of a schema in raw data model ("dmt") form into a compiled schema.TypeSystem, which is the ready-to-use form.

The first parameter is mutated by this process, and the second parameter is the data source.

The compilation process includes first inserting the "prelude" types into the schema.TypeSystem -- that is, the "type Bool bool" and "type String string", etc, which are generally presumed to be present in any type system.

The compilation process attempts to check the validity of the schema at a logical level as it goes. For example, references to type names not present elsewhere in the same schema are now an error (even though that has been easily representable in the dmt.Schema form up until this point).

Note that this API is EXPERIMENTAL and will likely change. It supports many features of IPLD Schemas, but it may yet not support all of them. It supports several validations for logical coherency of schemas, but may not yet successfully reject all invalid schemas.

Types

type AnyScalar

type AnyScalar struct {
	Bool   *bool
	String *string
	Bytes  *[]uint8
	Int    *int
	Float  *float64
}

type EnumRepresentation

type EnumRepresentation struct {
	EnumRepresentation_String *EnumRepresentation_String
	EnumRepresentation_Int    *EnumRepresentation_Int
}

type EnumRepresentation_Int

type EnumRepresentation_Int struct {
	Keys   []string
	Values map[string]int
}

type EnumRepresentation_String

type EnumRepresentation_String struct {
	Keys   []string
	Values map[string]string
}

type InlineDefn

type InlineDefn struct {
	TypeDefnMap  *TypeDefnMap
	TypeDefnList *TypeDefnList
	TypeDefnLink *TypeDefnLink
}

type ListRepresentation

type ListRepresentation struct {
	ListRepresentation_List *ListRepresentation_List
}

type ListRepresentation_List

type ListRepresentation_List struct {
}

type List__EnumMember

type List__EnumMember []string

type List__FieldName

type List__FieldName []string

type List__TypeName

type List__TypeName []string

type List__UnionMember

type List__UnionMember []UnionMember

type MapRepresentation

type MapRepresentation struct {
	MapRepresentation_Map         *MapRepresentation_Map
	MapRepresentation_Stringpairs *MapRepresentation_Stringpairs
	MapRepresentation_Listpairs   *MapRepresentation_Listpairs
}

type MapRepresentation_Listpairs

type MapRepresentation_Listpairs struct {
}

type MapRepresentation_Map

type MapRepresentation_Map struct {
}

type MapRepresentation_Stringpairs

type MapRepresentation_Stringpairs struct {
	InnerDelim string
	EntryDelim string
}

type Map__FieldName__StructField

type Map__FieldName__StructField struct {
	Keys   []string
	Values map[string]StructField
}

type Map__FieldName__StructRepresentation_Map_FieldDetails

type Map__FieldName__StructRepresentation_Map_FieldDetails struct {
	Keys   []string
	Values map[string]StructRepresentation_Map_FieldDetails
}

type Map__HexString__TypeName

type Map__HexString__TypeName struct {
	Keys   []string
	Values map[string]string
}

type Map__String__TypeName

type Map__String__TypeName struct {
	Keys   []string
	Values map[string]string
}

type Map__String__UnionMember

type Map__String__UnionMember struct {
	Keys   []string
	Values map[string]TypeDefn
}

type Map__TypeName__Int

type Map__TypeName__Int struct {
	Keys   []string
	Values map[string]int
}

type Map__TypeName__TypeDefn

type Map__TypeName__TypeDefn struct {
	Keys   []string
	Values map[string]TypeDefn
}

type Schema

type Schema struct {
	Types Map__TypeName__TypeDefn
}

func ConcatenateSchemas

func ConcatenateSchemas(a, b *Schema) *Schema

ConcatenateSchemas returns a new schema DMT object containing the type declarations from both.

As is usual for DMT form data, there is no check about the validity of the result yet; you'll need to apply `Compile` on the produced value to produce a usable compiled typesystem or to become certain that all references in the DMT are satisfied, etc.

type StructField

type StructField struct {
	Type     TypeNameOrInlineDefn
	Optional *bool
	Nullable *bool
}

type StructRepresentation

type StructRepresentation struct {
	StructRepresentation_Map         *StructRepresentation_Map
	StructRepresentation_Tuple       *StructRepresentation_Tuple
	StructRepresentation_Stringpairs *StructRepresentation_Stringpairs
	StructRepresentation_Stringjoin  *StructRepresentation_Stringjoin
	StructRepresentation_Listpairs   *StructRepresentation_Listpairs
}

type StructRepresentation_Listpairs

type StructRepresentation_Listpairs struct {
}

type StructRepresentation_Map

type StructRepresentation_Map struct {
	Fields *Map__FieldName__StructRepresentation_Map_FieldDetails
}

type StructRepresentation_Map_FieldDetails

type StructRepresentation_Map_FieldDetails struct {
	Rename   *string
	Implicit *AnyScalar
}

type StructRepresentation_Stringjoin

type StructRepresentation_Stringjoin struct {
	Join       string
	FieldOrder *List__FieldName
}

type StructRepresentation_Stringpairs

type StructRepresentation_Stringpairs struct {
	InnerDelim string
	EntryDelim string
}

type StructRepresentation_Tuple

type StructRepresentation_Tuple struct {
	FieldOrder *List__FieldName
}

type TypeDefn

type TypeDefn struct {
	TypeDefnBool   *TypeDefnBool
	TypeDefnString *TypeDefnString
	TypeDefnBytes  *TypeDefnBytes
	TypeDefnInt    *TypeDefnInt
	TypeDefnFloat  *TypeDefnFloat
	TypeDefnMap    *TypeDefnMap
	TypeDefnList   *TypeDefnList
	TypeDefnLink   *TypeDefnLink
	TypeDefnUnion  *TypeDefnUnion
	TypeDefnStruct *TypeDefnStruct
	TypeDefnEnum   *TypeDefnEnum
	TypeDefnUnit   *TypeDefnUnit
	TypeDefnAny    *TypeDefnAny
	TypeDefnCopy   *TypeDefnCopy
}

type TypeDefnAny

type TypeDefnAny struct {
}

type TypeDefnBool

type TypeDefnBool struct {
}

type TypeDefnBytes

type TypeDefnBytes struct {
}

type TypeDefnCopy

type TypeDefnCopy struct {
	FromType string
}

type TypeDefnEnum

type TypeDefnEnum struct {
	Members        List__EnumMember
	Representation EnumRepresentation
}

type TypeDefnFloat

type TypeDefnFloat struct {
}

type TypeDefnInt

type TypeDefnInt struct {
}

type TypeDefnLink

type TypeDefnLink struct {
	ExpectedType *string
}

type TypeDefnList

type TypeDefnList struct {
	ValueType      TypeNameOrInlineDefn
	ValueNullable  *bool
	Representation *ListRepresentation
}

type TypeDefnMap

type TypeDefnMap struct {
	KeyType        string
	ValueType      TypeNameOrInlineDefn
	ValueNullable  *bool
	Representation *MapRepresentation
}

type TypeDefnString

type TypeDefnString struct {
}

type TypeDefnStruct

type TypeDefnStruct struct {
	Fields         Map__FieldName__StructField
	Representation StructRepresentation
}

type TypeDefnUnion

type TypeDefnUnion struct {
	Members        List__UnionMember
	Representation UnionRepresentation
}

type TypeDefnUnit

type TypeDefnUnit struct {
	Representation string
}

type TypeNameOrInlineDefn

type TypeNameOrInlineDefn struct {
	TypeName   *string
	InlineDefn *InlineDefn
}

type UnionMember

type UnionMember struct {
	TypeName              *string
	UnionMemberInlineDefn *UnionMemberInlineDefn
}

type UnionMemberInlineDefn

type UnionMemberInlineDefn struct {
	TypeDefnLink *TypeDefnLink
}

type UnionRepresentation

type UnionRepresentation struct {
	UnionRepresentation_Kinded       *UnionRepresentation_Kinded
	UnionRepresentation_Keyed        *UnionRepresentation_Keyed
	UnionRepresentation_Envelope     *UnionRepresentation_Envelope
	UnionRepresentation_Inline       *UnionRepresentation_Inline
	UnionRepresentation_StringPrefix *UnionRepresentation_StringPrefix
	UnionRepresentation_BytesPrefix  *UnionRepresentation_BytesPrefix
}

type UnionRepresentation_BytesPrefix

type UnionRepresentation_BytesPrefix struct {
	Prefixes Map__HexString__TypeName
}

type UnionRepresentation_Envelope

type UnionRepresentation_Envelope struct {
	DiscriminantKey   string
	ContentKey        string
	DiscriminantTable Map__String__UnionMember
}

type UnionRepresentation_Inline

type UnionRepresentation_Inline struct {
	DiscriminantKey   string
	DiscriminantTable Map__String__TypeName
}

type UnionRepresentation_Keyed

type UnionRepresentation_Keyed struct {
	Keys   []string
	Values map[string]UnionMember
}

type UnionRepresentation_Kinded

type UnionRepresentation_Kinded struct {
	Keys   []string
	Values map[string]UnionMember
}

type UnionRepresentation_StringPrefix

type UnionRepresentation_StringPrefix struct {
	Prefixes Map__String__TypeName
}

type Unit

type Unit struct {
}