# Protocol Documentation <a name="top"></a> ## Table of Contents - [refs/types.proto](#refs/types.proto) - Messages - [Address](#neo.fs.v2.refs.Address) - [Checksum](#neo.fs.v2.refs.Checksum) - [ContainerID](#neo.fs.v2.refs.ContainerID) - [ObjectID](#neo.fs.v2.refs.ObjectID) - [OwnerID](#neo.fs.v2.refs.OwnerID) - [Signature](#neo.fs.v2.refs.Signature) - [Version](#neo.fs.v2.refs.Version) - [Scalar Value Types](#scalar-value-types) <a name="refs/types.proto"></a> <p align="right"><a href="#top">Top</a></p> ## refs/types.proto <!-- end services --> <a name="neo.fs.v2.refs.Address"></a> ### Message Address Objects in NeoFS are addressed by their ContainerID and ObjectID. String presentation of `Address` is the concatenation of string encoded `ContainerID` and `ObjectID` delimited by '/' character. | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | container_id | [ContainerID](#neo.fs.v2.refs.ContainerID) | | Container identifier | | object_id | [ObjectID](#neo.fs.v2.refs.ObjectID) | | Object identifier | <a name="neo.fs.v2.refs.Checksum"></a> ### Message Checksum Checksum message. Depending on checksum algorithm type the string presentation may vary: * TZ \ Hex encoded string without `0x` prefix * SHA256 \ Hex encoded string without `0x` prefix | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | type | [ChecksumType](#neo.fs.v2.refs.ChecksumType) | | Checksum algorithm type | | sum | [bytes](#bytes) | | Checksum itself | <a name="neo.fs.v2.refs.ContainerID"></a> ### Message ContainerID NeoFS container identifier. Container structures are immutable and content-addressed. `ContainerID` is a 32 byte long [SHA256](https://csrc.nist.gov/publications/detail/fips/180/4/final) hash of stable-marshalled container message. String presentation is [base58](https://tools.ietf.org/html/draft-msporny-base58-02) encoded string. JSON value will be the data encoded as a string using standard base64 encoding with paddings. Either [standard](https://tools.ietf.org/html/rfc4648#section-4) or [URL-safe](https://tools.ietf.org/html/rfc4648#section-5) base64 encoding with/without paddings are accepted. | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | value | [bytes](#bytes) | | Container identifier in a binary format. | <a name="neo.fs.v2.refs.ObjectID"></a> ### Message ObjectID NeoFS Object unique identifier. Objects are immutable and content-addressed. It means `ObjectID` will change if `header` or `payload` changes. `ObjectID` is a 32 byte long [SHA256](https://csrc.nist.gov/publications/detail/fips/180/4/final) hash of object's `header` field, which, in it's turn, contains hash of object's payload. String presentation is [base58](https://tools.ietf.org/html/draft-msporny-base58-02) encoded string. JSON value will be the data encoded as a string using standard base64 encoding with paddings. Either [standard](https://tools.ietf.org/html/rfc4648#section-4) or [URL-safe](https://tools.ietf.org/html/rfc4648#section-5) base64 encoding with/without paddings are accepted. | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | value | [bytes](#bytes) | | Object identifier in a binary format | <a name="neo.fs.v2.refs.OwnerID"></a> ### Message OwnerID `OwnerID` is a derivative of a user's main public key. The transformation algorithm is the same as for Neo3 wallet addresses. Neo3 wallet address can be directly used as `OwnerID`. `OwnerID` is a 25 bytes sequence starting with Neo version prefix byte followed by 20 bytes of ScrptHash and 4 bytes of checksum. String presentation is [Base58 Check](https://en.bitcoin.it/wiki/Base58Check_encoding) Encoded string. JSON value will be the data encoded as a string using standard base64 encoding with paddings. Either [standard](https://tools.ietf.org/html/rfc4648#section-4) or [URL-safe](https://tools.ietf.org/html/rfc4648#section-5) base64 encoding with/without paddings are accepted. | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | value | [bytes](#bytes) | | Identifier of the container owner in a binary format | <a name="neo.fs.v2.refs.Signature"></a> ### Message Signature Signature of something in NeoFS. | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | key | [bytes](#bytes) | | Public key used for signing | | sign | [bytes](#bytes) | | Signature | <a name="neo.fs.v2.refs.Version"></a> ### Message Version API version used by a node. String presentation is a Semantic Versioning 2.0.0 compatible version string with 'v' prefix. I.e. `vX.Y`, where `X` - major number, `Y` - minor number. | Field | Type | Label | Description | | ----- | ---- | ----- | ----------- | | major | [uint32](#uint32) | | Major API version | | minor | [uint32](#uint32) | | Minor API version | <!-- end messages --> <a name="neo.fs.v2.refs.ChecksumType"></a> ### ChecksumType Checksum algorithm type. | Name | Number | Description | | ---- | ------ | ----------- | | CHECKSUM_TYPE_UNSPECIFIED | 0 | Unknown. Not used | | TZ | 1 | Tillich-Zemor homomorphic hash function | | SHA256 | 2 | SHA-256 | <!-- end enums --> ## Scalar Value Types | .proto Type | Notes | C++ Type | Java Type | Python Type | | ----------- | ----- | -------- | --------- | ----------- | | <a name="double" /> double | | double | double | float | | <a name="float" /> float | | float | float | float | | <a name="int32" /> int32 | Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint32 instead. | int32 | int | int | | <a name="int64" /> int64 | Uses variable-length encoding. Inefficient for encoding negative numbers – if your field is likely to have negative values, use sint64 instead. | int64 | long | int/long | | <a name="uint32" /> uint32 | Uses variable-length encoding. | uint32 | int | int/long | | <a name="uint64" /> uint64 | Uses variable-length encoding. | uint64 | long | int/long | | <a name="sint32" /> sint32 | Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s. | int32 | int | int | | <a name="sint64" /> sint64 | Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s. | int64 | long | int/long | | <a name="fixed32" /> fixed32 | Always four bytes. More efficient than uint32 if values are often greater than 2^28. | uint32 | int | int | | <a name="fixed64" /> fixed64 | Always eight bytes. More efficient than uint64 if values are often greater than 2^56. | uint64 | long | int/long | | <a name="sfixed32" /> sfixed32 | Always four bytes. | int32 | int | int | | <a name="sfixed64" /> sfixed64 | Always eight bytes. | int64 | long | int/long | | <a name="bool" /> bool | | bool | boolean | boolean | | <a name="string" /> string | A string must always contain UTF-8 encoded or 7-bit ASCII text. | string | String | str/unicode | | <a name="bytes" /> bytes | May contain any arbitrary sequence of bytes. | string | ByteString | str |