frostfs-api/proto-docs/object.md

Protocol Documentation

Table of Contents

• object/service.proto

• Services

  • ObjectService

• Messages

  • DeleteRequest
  • DeleteRequest.Body
  • DeleteResponse
  • DeleteResponse.Body
  • GetRangeHashRequest
  • GetRangeHashRequest.Body
  • GetRangeHashResponse
  • GetRangeHashResponse.Body
  • GetRangeRequest
  • GetRangeRequest.Body
  • GetRangeResponse
  • GetRangeResponse.Body
  • GetRequest
  • GetRequest.Body
  • GetResponse
  • GetResponse.Body
  • GetResponse.Body.Init
  • HeadRequest
  • HeadRequest.Body
  • HeadResponse
  • HeadResponse.Body
  • HeaderWithSignature
  • PutRequest
  • PutRequest.Body
  • PutRequest.Body.Init
  • PutResponse
  • PutResponse.Body
  • Range
  • SearchRequest
  • SearchRequest.Body
  • SearchRequest.Body.Filter
  • SearchResponse
  • SearchResponse.Body

• object/types.proto

  • Messages
    • Header
    • Header.Attribute
    • Header.Split
    • Object
    • ShortHeader

• Scalar Value Types

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object/service.proto

Service "neo.fs.v2.object.ObjectService"

ObjectService provides API for manipulating objects. Object operations do not interact with sidechain and are only served by nodes in p2p style.

rpc Get(GetRequest) returns (stream GetResponse);
rpc Put(stream PutRequest) returns (PutResponse);
rpc Delete(DeleteRequest) returns (DeleteResponse);
rpc Head(HeadRequest) returns (HeadResponse);
rpc Search(SearchRequest) returns (stream SearchResponse);
rpc GetRange(GetRangeRequest) returns (stream GetRangeResponse);
rpc GetRangeHash(GetRangeHashRequest) returns (GetRangeHashResponse);

Method Get

Receive full object structure, including Headers and payload. Response uses gRPC stream. First response message carries object with requested address. Chunk messages are parts of the object's payload if it is needed. All messages, except the first one, carry payload chunks. Requested object can be restored by concatenation of object message payload and all chunks keeping receiving order.

Name	Input	Output
Get	GetRequest	GetResponse

Method Put

Put the object into container. Request uses gRPC stream. First message SHOULD be of PutHeader type. ContainerID and OwnerID of an object SHOULD be set. Session token SHOULD be obtained before PUT operation (see session package). Chunk messages are considered by server as a part of an object payload. All messages, except first one, SHOULD be payload chunks. Chunk messages SHOULD be sent in direct order of fragmentation.

Name	Input	Output
Put	PutRequest	PutResponse

Method Delete

Delete the object from a container. There is no immediate removal guarantee. Object will be marked for removal and deleted eventually.

Name	Input	Output
Delete	DeleteRequest	DeleteResponse

Method Head

Returns the object Headers without data payload. By default full header is returned. If main_only request field is set, the short header with only the very minimal information would be returned instead.

Name	Input	Output
Head	HeadRequest	HeadResponse

Method Search

Search objects in container. Search query allows to match by Object Header's filed values. Please see the corresponding NeoFS Technical Specification section for more details.

Name	Input	Output
Search	SearchRequest	SearchResponse

Method GetRange

Get byte range of data payload. Range is set as an (offset, length) tuple. Like in Get method, the response uses gRPC stream. Requested range can be restored by concatenation of all received payload chunks keeping receiving order.

Name	Input	Output
GetRange	GetRangeRequest	GetRangeResponse

Method GetRangeHash

Returns homomorphic or regular hash of object's payload range after applying XOR operation with the provided salt. Ranges are set of (offset, length) tuples. Hashes order in response corresponds to ranges order in request. Note that hash is calculated for XORed data.

Name	Input	Output
GetRangeHash	GetRangeHashRequest	GetRangeHashResponse

Message DeleteRequest

Object DELETE request

Field	Type	Label	Description
body	DeleteRequest.Body		Body of delete object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message DeleteRequest.Body

Object DELETE request body

Field	Type	Label	Description
address	neo.fs.v2.refs.Address		Address of the object to be deleted

Message DeleteResponse

DeleteResponse body is empty because we cannot guarantee permanent object removal in distributed system.

Field	Type	Label	Description
body	DeleteResponse.Body		Body of delete object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message DeleteResponse.Body

Object DELETE Response has an empty body.

Message GetRangeHashRequest

Get hash of object's payload part

Field	Type	Label	Description
body	GetRangeHashRequest.Body		Body of get range hash object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message GetRangeHashRequest.Body

Get hash of object's payload part request body.

Field	Type	Label	Description
address	neo.fs.v2.refs.Address		Address of the object that containing the requested payload range
ranges	Range	repeated	List of object's payload ranges to calculate homomorphic hash
salt	bytes		Binary salt to XOR object's payload ranges before hash calculation
type	neo.fs.v2.refs.ChecksumType		Checksum algorithm type

Message GetRangeHashResponse

Get hash of object's payload part

Field	Type	Label	Description
body	GetRangeHashResponse.Body		Body of get range hash object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message GetRangeHashResponse.Body

Get hash of object's payload part response body.

Field	Type	Label	Description
type	neo.fs.v2.refs.ChecksumType		Checksum algorithm type
hash_list	bytes	repeated	List of range hashes in a binary format

Message GetRangeRequest

Request part of object's payload

Field	Type	Label	Description
body	GetRangeRequest.Body		Body of get range object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message GetRangeRequest.Body

Byte range of object's payload request body

Field	Type	Label	Description
address	neo.fs.v2.refs.Address		Address of the object containing the requested payload range
range	Range		Requested payload range

Message GetRangeResponse

Get part of object's payload

Field	Type	Label	Description
body	GetRangeResponse.Body		Body of get range object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message GetRangeResponse.Body

Get Range response body uses streams to transfer the response. Because object payload considered a byte sequence, there is no need to have some initial preamble message. The requested byte range is sent as a series chunks.

Field	Type	Label	Description
chunk	bytes		Chunked object payload's range

Message GetRequest

GET object request

Field	Type	Label	Description
body	GetRequest.Body		Body of get object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message GetRequest.Body

GET Object request body

Field	Type	Label	Description
address	neo.fs.v2.refs.Address		Address of the requested object
raw	bool		If raw flag is set, request will work only with objects that are physically stored on the peer node

Message GetResponse

GET object response

Field	Type	Label	Description
body	GetResponse.Body		Body of get object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message GetResponse.Body

GET Object Response body

Field	Type	Label	Description
init	GetResponse.Body.Init		Initial part of the object stream
chunk	bytes		Chunked object payload

Message GetResponse.Body.Init

Initial part of the Object structure stream. Technically it's a set of all Object structure's fields except payload.

Field	Type	Label	Description
object_id	neo.fs.v2.refs.ObjectID		Object's unique identifier.
signature	neo.fs.v2.refs.Signature		Signed ObjectID
header	Header		Object metadata headers

Message HeadRequest

Object HEAD request

Field	Type	Label	Description
body	HeadRequest.Body		Body of head object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message HeadRequest.Body

Object HEAD request body

Field	Type	Label	Description
address	neo.fs.v2.refs.Address		Address of the object with the requested Header
main_only	bool		Return only minimal header subset
raw	bool		If raw flag is set, request will work only with objects that are physically stored on the peer node

Message HeadResponse

Object HEAD response

Field	Type	Label	Description
body	HeadResponse.Body		Body of head object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message HeadResponse.Body

Object HEAD response body

Field	Type	Label	Description
header	HeaderWithSignature		Full object's Header with ObjectID signature
short_header	ShortHeader		Short object header

Message HeaderWithSignature

Tuple of full object header and signature of ObjectID.
Signed ObjectID is present to verify full header's authenticity through the following steps:

1. Calculate SHA-256 of marshalled Header structure
2. Check if the resulting hash matched ObjectID
3. Check if ObjectID signature in signature field is correct

Field	Type	Label	Description
header	Header		Full object header
signature	neo.fs.v2.refs.Signature		Signed ObjectID to verify full header's authenticity

Message PutRequest

PUT object request

Field	Type	Label	Description
body	PutRequest.Body		Body of put object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message PutRequest.Body

PUT request body

Field	Type	Label	Description
init	PutRequest.Body.Init		Initial part of the object stream
chunk	bytes		Chunked object payload

Message PutRequest.Body.Init

Newly created object structure parameters. If some optional parameters are not set, they will be calculated by a peer node.

Field	Type	Label	Description
object_id	neo.fs.v2.refs.ObjectID		ObjectID if available.
signature	neo.fs.v2.refs.Signature		Object signature if available
header	Header		Object's Header
copies_number	uint32		Number of the object copies to store within the RPC call. By default object is processed according to the container's placement policy.

Message PutResponse

PUT Object response

Field	Type	Label	Description
body	PutResponse.Body		Body of put object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message PutResponse.Body

PUT Object response body

Field	Type	Label	Description
object_id	neo.fs.v2.refs.ObjectID		Identifier of the saved object

Message Range

Object payload range.Ranges of zero length SHOULD be considered as invalid.

Field	Type	Label	Description
offset	uint64		Offset of the range from the object payload start
length	uint64		Length in bytes of the object payload range

Message SearchRequest

Object Search request

Field	Type	Label	Description
body	SearchRequest.Body		Body of search object request message.
meta_header	neo.fs.v2.session.RequestMetaHeader		Carries request meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.RequestVerificationHeader		Carries request verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message SearchRequest.Body

Object Search request body

Field	Type	Label	Description
container_id	neo.fs.v2.refs.ContainerID		Container identifier were to search
version	uint32		Version of the Query Language used
filters	SearchRequest.Body.Filter	repeated	List of search expressions

Message SearchRequest.Body.Filter

Filter structure checks if object header field or attribute content matches a value.

By default key field refers to the corresponding object's Attribute. Some Object's header fields can also be accessed by adding $Object: prefix to the name. Here is the list of fields available via this prefix:

• $Object:version
  version
• $Object:containerID
  container_id
• $Object:ownerID
  owner_id
• $Object:creationEpoch
  creation_epoch
• $Object:payloadLength
  payload_length
• $Object:payloadHash
  payload_hash
• $Object:objectType
  object_type
• $Object:homomorphicHash
  homomorphic_hash
• $Object:split.parent
  object_id of parent

There are some well-known filter aliases to match objects by certain properties:

• $Object:ROOT
  With the value set to true checks if an object is a top object in a split hierarchy. With other values returns non-root objects.
• $Object:LEAF
  With the value set to true checks if an object is a leaf in a split hierarchy. With other values returns non-leaf objects.
• $Object:CHILDFREE
  With the value set to true checks if an object has empty children list in Split header. With other values returns non-childfree objects.

Field	Type	Label	Description
match_type	MatchType		Match type to use
key	string		Attribute or Header fields to match
value	string		Value to match

Message SearchResponse

Search response

Field	Type	Label	Description
body	SearchResponse.Body		Body of search object response message.
meta_header	neo.fs.v2.session.ResponseMetaHeader		Carries response meta information. Header data is used only to regulate message transport and does not affect request execution.
verify_header	neo.fs.v2.session.ResponseVerificationHeader		Carries response verification information. This header is used to authenticate the nodes of the message route and check the correctness of transmission.

Message SearchResponse.Body

Object Search response body

Field	Type	Label	Description
id_list	neo.fs.v2.refs.ObjectID	repeated	List of ObjectIDs that match the search query

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object/types.proto

Message Header

Object Header

Field	Type	Label	Description
version	neo.fs.v2.refs.Version		Object format version. Effectively the version of API library used to create particular object
container_id	neo.fs.v2.refs.ContainerID		Object's container
owner_id	neo.fs.v2.refs.OwnerID		Object's owner
creation_epoch	uint64		Object creation Epoch
payload_length	uint64		Size of payload in bytes. 0xFFFFFFFFFFFFFFFF means payload_length is unknown
payload_hash	neo.fs.v2.refs.Checksum		Hash of payload bytes
object_type	ObjectType		Type of the object payload content
homomorphic_hash	neo.fs.v2.refs.Checksum		Homomorphic hash of the object payload.
session_token	neo.fs.v2.session.SessionToken		Session token, if it was used during Object creation. Need it to verify integrity and authenticity out of Request scope.
attributes	Header.Attribute	repeated	User-defined object attributes
split	Header.Split		Position of the object in the split hierarchy

Message Header.Attribute

Attribute is a user-defined Key-Value metadata pair attached to the object.

There are some "well-known" attributes starting with __NEOFS__ prefix that affect system behaviour:

• __NEOFS__UPLOAD_ID
  Marks smaller parts of a split bigger object
• __NEOFS__EXPIRATION_EPOCH
  Tells GC to delete object after that epoch

And some well-known attributes used by applications only:

• Name
  Human-friendly name
• FileName
  File name to be associated with the object on saving
• Timestamp
  User-defined local time of object creation in Unix Timestamp format

For detailed description of each well-known attribute please see the corresponding section in NeoFS Technical specification.

Field	Type	Label	Description
key	string		string key to the object attribute
value	string		string value of the object attribute

Message Header.Split

Bigger objects can be split into a chain of smaller objects. Information about inter-dependencies between spawned objects and how to re-construct the original one is in the Split headers. Parent and children objects must be within the same container.

Field	Type	Label	Description
parent	neo.fs.v2.refs.ObjectID		Identifier of the origin object. Known only to the minor child.
previous	neo.fs.v2.refs.ObjectID		Identifier of the left split neighbor
parent_signature	neo.fs.v2.refs.Signature		signature field of the parent object. Used to reconstruct parent.
parent_header	Header		header field of the parent object. Used to reconstruct parent.
children	neo.fs.v2.refs.ObjectID	repeated	List of identifiers of the objects generated by splitting current one.

Message Object

Object structure. Object is immutable and content-addressed. It means ObjectID will change if header or payload changes. It's calculated as a hash of header field, which contains hash of object's payload.

Field	Type	Label	Description
object_id	neo.fs.v2.refs.ObjectID		Object's unique identifier.
signature	neo.fs.v2.refs.Signature		Signed object_id
header	Header		Object metadata headers
payload	bytes		Payload bytes.

Message ShortHeader

Short header fields

Field	Type	Label	Description
version	neo.fs.v2.refs.Version		Object format version. Effectively the version of API library used to create particular object
creation_epoch	uint64		Epoch when the object was created
owner_id	neo.fs.v2.refs.OwnerID		Object's owner
object_type	ObjectType		Type of the object payload content
payload_length	uint64		Size of payload in bytes. 0xFFFFFFFFFFFFFFFF means payload_length is unknown

MatchType

Type of match expression

Name	Number	Description
MATCH_TYPE_UNSPECIFIED	0	Unknown. Not used
STRING_EQUAL	1	Full string match

ObjectType

Type of the object payload content.

Name	Number	Description
REGULAR	0	Just a normal object
TOMBSTONE	1	Used internally to identify deleted objects
STORAGE_GROUP	2	StorageGroup information

Scalar Value Types

.proto Type	Notes	C++ Type	Java Type	Python Type
double		double	double	float
float		float	float	float
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
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
uint32	Uses variable-length encoding.	uint32	int	int/long
uint64	Uses variable-length encoding.	uint64	long	int/long
sint32	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s.	int32	int	int
sint64	Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s.	int64	long	int/long
fixed32	Always four bytes. More efficient than uint32 if values are often greater than 2^28.	uint32	int	int
fixed64	Always eight bytes. More efficient than uint64 if values are often greater than 2^56.	uint64	long	int/long
sfixed32	Always four bytes.	int32	int	int
sfixed64	Always eight bytes.	int64	long	int/long
bool		bool	boolean	boolean
string	A string must always contain UTF-8 encoded or 7-bit ASCII text.	string	String	str/unicode
bytes	May contain any arbitrary sequence of bytes.	string	ByteString	str