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grpc.proto

RdfStreamReceived

Acknowledgement of receiving a stream sent by the server to the client.

RdfStreamSubscribe

Subscribe command sent by the client to the server.

Field Type Label Description
topic string The topic to which the client wants to subscribe (UTF-8 encoded).
requested_options RdfStreamOptions Optional: the stream options requested by the client. The server should respond with a stream that matches these options. In case that is not possible, the server must respond with the INVALID_ARGUMENT error.

RdfStreamService

Pub/Sub service for RDF streams, to be implemented by the server.

Method Name Request Type Response Type Description
SubscribeRdf RdfStreamSubscribe RdfStreamFrame stream Subscribe to an RDF stream.
PublishRdf RdfStreamFrame stream RdfStreamReceived Publish an RDF stream. In case the server cannot process the stream, it must respond with the INVALID_ARGUMENT error.

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patch.proto

RdfPatchFrame

A batch of RDF patch rows.

Field Type Label Description
rows RdfPatchRow repeated Patch rows

RdfPatchHeader

Metadata header for RDF Patch. Header rows must occur at the start of the patch frame.

Field Type Label Description
key string Header key (required)
h_iri eu.ostrzyciel.jelly.core.proto.v1.RdfIri IRI
h_bnode string Blank node
h_literal eu.ostrzyciel.jelly.core.proto.v1.RdfLiteral Literal
h_triple_term eu.ostrzyciel.jelly.core.proto.v1.RdfTriple RDF-star quoted triple

RdfPatchNamespace

Field Type Label Description
name string Short name of the namespace (e.g., "ex") Do NOT include the colon.
value eu.ostrzyciel.jelly.core.proto.v1.RdfIri IRI of the namespace (e.g., "http://example.org/")..) Optional in the "prefix delete" (PD) operation, but required in the "prefix add" (PA) operation.
g_iri eu.ostrzyciel.jelly.core.proto.v1.RdfIri IRI
g_bnode string Blank node
g_default_graph eu.ostrzyciel.jelly.core.proto.v1.RdfDefaultGraph Default graph
g_literal eu.ostrzyciel.jelly.core.proto.v1.RdfLiteral Literal – only valid for generalized RDF streams

RdfPatchOptions

RDF Patch stream options

Field Type Label Description
statement_type PatchStatementType Type of statements in the stream (required)
stream_type PatchStreamType Type of the stream (required)
generalized_statements bool Whether the stream may contain generalized triples, quads, or datasets
rdf_star bool Whether the stream may contain RDF-star statements
max_name_table_size uint32 Maximum size of the name lookup table (required, must be >= 8)
max_prefix_table_size uint32 Maximum size of the prefix lookup table (required if the prefix lookup is used)
max_datatype_table_size uint32 Maximum size of the datatype lookup table (required if datatype literals are used)
version uint32 Protocol version (required) For Jelly-Patch 1.0.x (based on Jelly-RDF 1.1.x), the value must be 1. For custom extensions, the value must be 10000 or higher.

RdfPatchPunctuation

RdfPatchRow

A row in an RDF Patch stream

Field Type Label Description
options RdfPatchOptions Stream options. Must be the first row in the stream.
statement_add eu.ostrzyciel.jelly.core.proto.v1.RdfQuad Add a triple/quad statement (A)
statement_delete eu.ostrzyciel.jelly.core.proto.v1.RdfQuad Delete a triple/quad statement (D)
namespace_add RdfPatchNamespace Add a namespace/prefix declaration (PA)
namespace_delete RdfPatchNamespace Delete a namespace/prefix declaration (PD)
transaction_start RdfPatchTransactionStart Transaction start (TX)
transaction_commit RdfPatchTransactionCommit Transaction commit (TC)
transaction_abort RdfPatchTransactionAbort Transaction abort (TA)
name eu.ostrzyciel.jelly.core.proto.v1.RdfNameEntry Entry in the name lookup table.
prefix eu.ostrzyciel.jelly.core.proto.v1.RdfPrefixEntry Entry in the prefix lookup table.
datatype eu.ostrzyciel.jelly.core.proto.v1.RdfDatatypeEntry Entry in the datatype lookup table.
header RdfPatchHeader Header entry (H)
punctuation RdfPatchPunctuation Punctuation mark, only used in stream type PUNCTUATED Indicates the end of a patch.

RdfPatchTransactionAbort

RdfPatchTransactionCommit

RdfPatchTransactionStart

PatchStatementType

Type of statements in the stream. This determines whether the statements are interpreted as triples or quads.

Name Number Description
PATCH_STATEMENT_TYPE_UNSPECIFIED 0 Unspecified stream type – invalid
PATCH_STATEMENT_TYPE_TRIPLES 1 RDF triples
PATCH_STATEMENT_TYPE_QUADS 2 RDF quads

PatchStreamType

Type of the stream. This determines whether each RdfPatchFrame is a complete patch by itself, or part of a larger patch.

Name Number Description
PATCH_STREAM_TYPE_UNSPECIFIED 0 Unspecified stream type – invalid
PATCH_STREAM_TYPE_FRAME 1 Each RdfPatchFrame is a complete patch. In this case, transactions cannot span multiple frames.
PATCH_STREAM_TYPE_FLAT 2 Entire stream is a single patch. Transactions may span multiple frames.
PATCH_STREAM_TYPE_PUNCTUATED 3 Stream contains multiple patches separated by punctuation marks. Patches and transactions may span multiple frames. Each frame must contain at most one patch.

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rdf.proto

RdfColumn

Column of RDF terms: the cells of one statement position (Jelly-RDF) or one variable (Jelly-SPARQL) across all rows of a batch, in row order. A cell is either an RDF term or unbound.

Each run of consecutive equal terms is stored once, as a run value, and unbound cells are not stored. The run values are split by type into separate lists. kinds gives the type of each run value, and layouts gives the runs of repeated values and of unbound cells.

Used by the column layout and by Jelly-SPARQL.

Field Type Label Description
kinds bytes Type of each run value, 2 bits per value, four values per byte, starting from the least significant bits: 0 = IRI, 1 = literal, 2 = blank node, 3 = triple term. Should be empty if all run values are of one type.
layouts uint32 repeated Sequence layout: where the run values repeat, and where the unbound cells are. Each entry is a token (skip << 5)
name_ids uint32 repeated Name identifiers of the IRIs, in row order. 0 means "previous name_id + 1", or 1 in the first IRI of the column.
prefix_ids uint32 repeated Prefix identifiers of the IRIs: none (no prefix), one (the same prefix for all IRIs), or one per IRI. 0 means "the same prefix as the previous IRI", or no prefix in the first IRI of the column.
lex_values string repeated Lexical forms of the literals, in row order.
literal_kinds uint32 repeated Literal kinds of the literals: none (all are simple literals), one (the same kind for all literals), or one per literal. 0 – simple literal (xsd:string) odd v – literal with the datatype (v + 1) / 2 of the datatype lookup even v > 0 – language-tagged string with the language tag langtags[v / 2 - 1]
langtags string repeated Language tags referred to by literal_kinds.
langtag_directions uint32 repeated Base directions of the language tags (RdfBaseDirection values), parallel to langtags. Empty means no base direction for any tag.
bnodes string repeated Labels of the blank nodes, in row order.
triple_terms RdfTripleTerm repeated Triple terms, in row order. The IRIs inside the triple terms are inferred separately from name_ids and prefix_ids.

RdfColumnBatch

The contents of a frame in the column layout: a batch of statements, and the lookup entries and namespace declarations they need.

Each statement is made up of the cells at the same position in the subjects, predicates, objects, and graphs columns.

Field Type Label Description
row_count uint32 Number of statements in the batch. At most 2^27 - 1.
names RdfLookupEntryPacked repeated Entries of the name lookup table.
prefixes RdfLookupEntryPacked repeated Entries of the prefix lookup table. Note: the prefixes in the lookup table can be arbitrary strings, and are NOT meant to be user-facing. They are only used for IRI compression. To transmit user-facing namespace declarations, use namespaces.
datatypes RdfLookupEntryPacked repeated Entries of the datatype lookup table.
namespaces RdfNamespaceDeclaration repeated Namespace declarations.
subjects RdfColumn Subjects: IRIs or blank nodes. No cell may be unbound.
predicates RdfColumn Predicates: IRIs. No cell may be unbound.
objects RdfColumn Objects: IRIs, blank nodes, literals, or triple terms. No cell may be unbound.
graphs RdfColumn Graph names: IRIs or blank nodes. An unbound cell is the default graph. Only valid if the physical type is QUADS. If not set, all statements of the batch are in the default graph.
message_lengths uint32 repeated Message boundaries: each value adds that many more statements to the current RDF Message, and then ends it. Only valid in streams of type RDF_STREAM_TYPE_MESSAGES.

RdfDatatypeEntry

Entry in the datatype lookup table

Not used in the column layout.

Field Type Label Description
id uint32 1-based identifier If id=0, it should be interpreted as previous_id + 1. If id=0 appears in the first RdfDatatypeEntry of the stream, it should be interpreted as 1.
value string Value of the datatype (UTF-8 encoded)

RdfDefaultGraph

Empty message indicating the default RDF graph.

Not used in the column layout.

RdfGraphEnd

End of a graph in a GRAPHS stream

Not used in the column layout.

RdfGraphStart

Start of a graph in a GRAPHS stream

In contrast to RdfQuad, setting the graph oneof to some value is always required. No repeated terms are allowed.

Not used in the column layout.

Field Type Label Description
g_iri RdfIri IRI
g_bnode string Blank node
g_default_graph RdfDefaultGraph Default graph
g_literal RdfLiteral Literal – only valid for generalized RDF streams

RdfIri

RDF IRI, encoded as a prefix and a name from the lookup tables. The IRI is the prefix followed by the name.

Field Type Label Description
prefix_id uint32 1-based identifier of the prefix in the prefix lookup. 0 means "the same prefix as in the previous IRI", or no prefix in the first IRI. Which IRI is the previous one depends on the layout.
name_id uint32 1-based identifier of the name in the name lookup. 0 means "the name_id of the previous IRI + 1", or 1 in the first IRI.

RdfLiteral

RDF literal

Field Type Label Description
lex string The lexical form of the literal.
langtag string Language tag of a language-tagged string.
datatype uint32 1-based identifier of the datatype in the datatype lookup. 0 is invalid (in contrast to prefix_id and name_id in RdfIri). If column layout: must not refer to rdf:langString or rdf:dirLangString.
direction RdfBaseDirection Base direction of a language-tagged string (RDF 1.2). If column layout: may be set only if langtag is set. If row layout: must not be set.

RdfLookupEntryPacked

Packed entries of a lookup table (name, prefix, or datatype): the values of a run of consecutive identifiers.

Used by the column layout and by Jelly-SPARQL.

Field Type Label Description
id uint32 1-based identifier of the first value. 0 means "the identifier after the last value of the previous entry of the same lookup table", or 1 in the first entry of the table.
values string repeated Values of the entries (UTF-8 encoded), for consecutive identifiers starting at id.

RdfNameEntry

Entry in the name lookup table

Not used in the column layout.

Field Type Label Description
id uint32 1-based identifier If id=0, it should be interpreted as previous_id + 1. If id=0 appears in the first RdfNameEntry of the stream, it should be interpreted as 1.
value string Value of the name (UTF-8 encoded)

RdfNamespaceDeclaration

Explicit namespace declaration

This is a hint to the consumer that the given IRI (namespace) may be associated with a short name, like in Turtle syntax: PREFIX ex: <http://example.org/>

This is a purely cosmetic feature, not part of the RDF data. It has nothing in common with the prefix lookup table. A declaration stays in effect until the same name is declared again.

Field Type Label Description
name string Short name of the namespace (e.g., "ex") Do NOT include the colon.
value RdfIri IRI of the namespace (e.g., "http://example.org/"))

RdfPrefixEntry

Entry in the prefix lookup table

Note: the prefixes in the lookup table can be arbitrary strings, and are NOT meant to be user-facing. They are only used for IRI compression. To transmit user-facing namespace declarations for cosmetic purposes, use RdfNamespaceDeclaration.

Not used in the column layout.

Field Type Label Description
id uint32 1-based identifier If id=0, it should be interpreted as previous_id + 1. If id=0 appears in the first RdfPrefixEntry of the stream, it should be interpreted as 1.
value string Value of the prefix (UTF-8 encoded)

RdfQuad

RDF quad

Fields 1–12 are repeated from RdfTriple for performance reasons.

Similarly to RdfTriple, this message allows for representing generalized RDF quads (for example, with literals as predicates). Whether this is used in the stream is determined by the stream options (see RdfStreamOptions).

If no field in a given oneof is set, the term is interpreted as a repeated term – the same as the term in the same position in the previous quad. In the first quad of the stream, all terms must be set.

Not used in the column layout.

Field Type Label Description
s_iri RdfIri IRI
s_bnode string Blank node
s_literal RdfLiteral Literal Only valid in a generalized RDF stream.
s_triple_term RdfTriple RDF-star quoted triple
p_iri RdfIri IRI
p_bnode string Blank node Only valid in a generalized RDF stream.
p_literal RdfLiteral Literal Only valid in a generalized RDF stream.
p_triple_term RdfTriple RDF-star quoted triple
o_iri RdfIri IRI
o_bnode string Blank node
o_literal RdfLiteral Literal
o_triple_term RdfTriple RDF-star quoted triple
g_iri RdfIri IRI
g_bnode string Blank node
g_default_graph RdfDefaultGraph Default graph
g_literal RdfLiteral Literal – only valid for generalized RDF streams

RdfStreamFrame

RDF stream frame – base message for RDF streams.

Field Type Label Description
rows RdfStreamRow repeated Stream rows. If row layout: the contents of the frame. If column layout: either empty, or exactly one row with the stream options.
columns RdfColumnBatch If column layout: the contents of the frame. If row layout: must not be set.
metadata RdfStreamFrame.MetadataEntry repeated Arbitrary metadata The keys are UTF-8 encoded strings, the values are byte arrays. This may be used by implementations in any way they see fit. The metadata does not affect the RDF data in any way, treat it as comments in a text file.

RdfStreamFrame.MetadataEntry

Field Type Label Description
key string
value bytes

RdfStreamOptions

RDF stream options

If row layout: the options may occur again later in the stream, but must be identical to the first occurrence. If column layout: a later frame may restate the options, which empties the lookup tables. This makes streams concatenable. physical_type, stream_type, and version must stay the same.

Field Type Label Description
stream_name string Name of the stream (completely optional). This may be used for, e.g., topic names in a pub/sub system.
physical_type PhysicalStreamType Type of the stream (required). If row layout: TRIPLES, QUADS, or GRAPHS. If column layout: TRIPLES or QUADS.
generalized_statements bool If row layout: whether the stream may contain generalized triples, quads, or datasets. If column layout: must not be set.
rdf_star bool If row layout: whether the stream may contain RDF-star statements. If column layout: must not be set – use rdf_version instead.
stream_type RdfStreamType If column layout: whether the stream is one RDF graph or dataset, or a stream of RDF Messages. Defaults to RDF_STREAM_TYPE_FLAT. If row layout: must not be set.
rdf_version RdfVersion If column layout: version of RDF whose terms may occur in the stream. Unspecified (the default) means that no version is announced, and the stream may contain any RDF 1.2 term. If row layout: must not be set.
max_name_table_size uint32 Maximum size of the name lookup table (required). If row layout: must be >= 8. If column layout: must be >= 128.
max_prefix_table_size uint32 Maximum size of the prefix lookup table (required if the prefix lookup is used)
max_datatype_table_size uint32 Maximum size of the datatype lookup table (required if datatype literals are used)
logical_type LogicalStreamType If row layout: logical (RDF-STaX-based) stream type. In contrast to the physical type, this field is entirely optional. If column layout: must not be set – use stream_type instead.
version uint32 Protocol version (required) For Jelly-RDF 1.0.x the value must be 1 (row layout). For Jelly-RDF 1.1.x the value must be 2 (row layout). For Jelly-RDF 1.2.x the value must be 3 (column layout). For custom extensions, the value must be 10000 or higher.

RdfStreamRow

RDF stream row

If row layout: one element of a frame. If column layout: only the options field may be set.

Field Type Label Description
options RdfStreamOptions Stream options. Must occur at the start of the stream.
triple RdfTriple RDF triple statement. Valid in streams of physical type TRIPLES or GRAPHS.
quad RdfQuad RDF quad statement. Only valid in streams of physical type QUADS.
graph_start RdfGraphStart Graph boundary: ends the currently transmitted graph and starts a new one Only valid in streams of physical type GRAPHS.
graph_end RdfGraphEnd Explicit end of a graph. Signals the consumer that the transmitted graph is complete. Only valid in streams of physical type GRAPHS.
namespace RdfNamespaceDeclaration Explicit namespace declaration.
name RdfNameEntry Entry in the name lookup table.
prefix RdfPrefixEntry Entry in the prefix lookup table.
datatype RdfDatatypeEntry Entry in the datatype lookup table.

RdfTriple

RDF triple

For each term (subject, predicate, object), the fields are repeated for performance reasons. This is to avoid the need for boxing each term in a separate message.

Note: this message allows for representing generalized RDF triples (for example, with literals as predicates). Whether this is used in the stream is determined by the stream options (see RdfStreamOptions).

If no field in a given oneof is set, the term is interpreted as a repeated term – the same as the term in the same position in the previous triple. In the first triple of the stream, all terms must be set. All terms must also be set in quoted triples (RDF-star).

Not used in the column layout.

Field Type Label Description
s_iri RdfIri IRI
s_bnode string Blank node
s_literal RdfLiteral Literal Only valid in a generalized RDF stream.
s_triple_term RdfTriple RDF-star quoted triple
p_iri RdfIri IRI
p_bnode string Blank node Only valid in a generalized RDF stream.
p_literal RdfLiteral Literal Only valid in a generalized RDF stream.
p_triple_term RdfTriple RDF-star quoted triple
o_iri RdfIri IRI
o_bnode string Blank node
o_literal RdfLiteral Literal
o_triple_term RdfTriple RDF-star quoted triple

RdfTripleTerm

RDF 1.2 triple term. All three positions must be set, and only the object may be a nested triple term. The field numbers are the same as in RdfTriple.

Used by the column layout and by Jelly-SPARQL.

Field Type Label Description
s_iri RdfIri IRI
s_bnode string Blank node
p_iri RdfIri Predicate
o_iri RdfIri IRI
o_bnode string Blank node
o_literal RdfLiteral Literal
o_triple_term RdfTripleTerm Nested triple term

LogicalStreamType

Logical stream type, according to the RDF Stream Taxonomy (RDF-STaX). If column layout: not used – use RdfStreamType instead.

Type 0 is reserved for the unspecified stream type. The rest of the type numbers follow the taxonomical structure of RDF-STaX. For example: 1 is a subtype of 0, 13 and 23 are subtypes of 3, 114 is a subtype of 14, etc.

Types 1–4 correspond to the four base concrete stream types. Their subtypes can be in most cases simply processed in the same way as the base types. Therefore, implementations can take the modulo 10 of the stream type to determine the base type of the stream and use this information to select the appropriate processing logic.

RDF-STaX version: 1.1.2 https://w3id.org/stax/1.1.2

Not used in the column layout.

Name Number Description
LOGICAL_STREAM_TYPE_UNSPECIFIED 0 Unspecified stream type – invalid
LOGICAL_STREAM_TYPE_FLAT_TRIPLES 1 Flat RDF triple stream https://w3id.org/stax/ontology#flatTripleStream
LOGICAL_STREAM_TYPE_FLAT_QUADS 2 Flat RDF quad stream https://w3id.org/stax/ontology#flatQuadStream
LOGICAL_STREAM_TYPE_GRAPHS 3 RDF graph stream https://w3id.org/stax/ontology#graphStream
LOGICAL_STREAM_TYPE_DATASETS 4 RDF dataset stream https://w3id.org/stax/ontology#datasetStream
LOGICAL_STREAM_TYPE_SUBJECT_GRAPHS 13 RDF subject graph stream (subtype of RDF graph stream) https://w3id.org/stax/ontology#subjectGraphStream
LOGICAL_STREAM_TYPE_NAMED_GRAPHS 14 RDF named graph stream (subtype of RDF dataset stream) https://w3id.org/stax/ontology#namedGraphStream
LOGICAL_STREAM_TYPE_TIMESTAMPED_NAMED_GRAPHS 114 RDF timestamped named graph stream (subtype of RDF dataset stream) https://w3id.org/stax/ontology#timestampedNamedGraphStream

PhysicalStreamType

Physical stream type: whether the stream contains triples or quads.

Name Number Description
PHYSICAL_STREAM_TYPE_UNSPECIFIED 0 Unspecified stream type – invalid
PHYSICAL_STREAM_TYPE_TRIPLES 1 RDF triples
PHYSICAL_STREAM_TYPE_QUADS 2 RDF quads
PHYSICAL_STREAM_TYPE_GRAPHS 3 RDF triples grouped in graphs. If column layout: invalid.

RdfBaseDirection

Initial text direction of a language-tagged string (RDF 1.2).

Name Number Description
RDF_BASE_DIRECTION_UNSPECIFIED 0 No base direction: an ordinary language-tagged string (rdf:langString).
RDF_BASE_DIRECTION_LTR 1 Left-to-right ("ltr"): a directional language-tagged string (rdf:dirLangString).
RDF_BASE_DIRECTION_RTL 2 Right-to-left ("rtl"): a directional language-tagged string (rdf:dirLangString).

RdfStreamType

Type of an RDF stream. Not used in the row layout.

Name Number Description
RDF_STREAM_TYPE_FLAT 0 The entire stream is one RDF graph (TRIPLES) or one RDF dataset (QUADS). This is the default. buf:lint:ignore ENUM_ZERO_VALUE_SUFFIX
RDF_STREAM_TYPE_MESSAGES 1 The stream is a sequence of RDF Messages, each an RDF graph or dataset: https://w3c-cg.github.io/rsp/spec/messages The messages are delimited by RdfColumnBatch.message_lengths.

RdfVersion

Version of RDF that a stream conforms to, following the version labels of RDF 1.2 Concepts: https://www.w3.org/TR/rdf12-concepts/#defined-version-labels

Name Number Description
RDF_VERSION_UNSPECIFIED 0 Unspecified. Each format that uses this enum defines how to interpret it.
RDF_VERSION_1_1 1 RDF 1.1 (version label "1.1"): no triple terms, no base directions.
RDF_VERSION_1_2_BASIC 2 RDF 1.2 Basic (version label "1.2-basic"): base directions are allowed, triple terms are not.
RDF_VERSION_1_2 3 RDF 1.2 (version label "1.2"): base directions and triple terms are allowed.

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sparql.proto

SparqlAskResult

Boolean result of a SPARQL ASK query.

Field Type Label Description
value bool The boolean value of the result.

SparqlResultsFrame

SPARQL results frame – base message of a SPARQL result stream. A frame contains a batch of rows (solutions).

Field Type Label Description
options SparqlResultsOptions Stream options. Must be set in the first frame of the stream. May be set again in a later frame, which empties the lookup tables.
variables string repeated Result set header: the names of the variables, in projection (SELECT clause) order, without the leading "?" or "$". Set in the first frame of a result set with a solution sequence, and in a frame that contains the options.
row_count uint32 Number of rows (solutions) in this frame. At most 2^27 - 1.
names eu.ostrzyciel.jelly.core.proto.v1.RdfLookupEntryPacked repeated Entries in the name lookup table.
prefixes eu.ostrzyciel.jelly.core.proto.v1.RdfLookupEntryPacked repeated Entries in the prefix lookup table. Note: the prefixes in the lookup table can be arbitrary strings, and are NOT meant to be user-facing. They are only used for IRI compression.
datatypes eu.ostrzyciel.jelly.core.proto.v1.RdfLookupEntryPacked repeated Entries in the datatype lookup table.
columns eu.ostrzyciel.jelly.core.proto.v1.RdfColumn repeated Columns, one per variable, in the order of variables, or none.
ask_result SparqlAskResult Boolean (ASK) result. If set, the result set is a boolean result instead of a solution sequence. A boolean result is always the only frame of its result set.
trailer SparqlResultsTrailer End-of-result-set marker. See SparqlResultsTrailer.
metadata SparqlResultsFrame.MetadataEntry repeated Arbitrary metadata The keys are UTF-8 encoded strings, the values are byte arrays. The metadata does not affect the result data in any way, treat it as comments in a text file. Well-known keys (their values must be valid UTF-8): link – zero or more IRIs separated by LF (U+000A), describing the result set as a whole (not the frame). Corresponds to head.link in the SPARQL Query Results JSON format. All other keys may be used by implementations in any way they see fit, and their values are arbitrary bytes.

SparqlResultsFrame.MetadataEntry

Field Type Label Description
key string
value bytes

SparqlResultsOptions

Stream options for SPARQL result streams.

Field Type Label Description
stream_name string Name of the stream (completely optional). This may be used for, e.g., topic names in a pub/sub system.
stream_type SparqlStreamType Type of the stream: one result set, or a sequence of result sets. Defaults to SPARQL_STREAM_TYPE_FLAT.
rdf_version eu.ostrzyciel.jelly.core.proto.v1.RdfVersion Version of RDF whose terms may occur in the stream. RDF_VERSION_1_1 – no triple terms, no base directions RDF_VERSION_1_2_BASIC – base directions, no triple terms RDF_VERSION_1_2 – base directions and triple terms Unspecified (the default) means that no version is announced: the stream may contain any RDF 1.2 term.
max_name_table_size uint32 Maximum size of the name lookup table (required, must be >= 128)
max_prefix_table_size uint32 Maximum size of the prefix lookup table (required if the prefix lookup is used)
max_datatype_table_size uint32 Maximum size of the datatype lookup table (required if datatype literals are used)
version uint32 Protocol version (required) For Jelly-SPARQL 1.0.x, the value must be 1. For custom extensions, the value must be 10000 or higher.

SparqlResultsTrailer

End-of-result-set marker, saying whether the result set is complete. Producers must write it in the last frame of every result set, unless they cannot write anything more at all (for example, because the process died).

Field Type Label Description
error string Empty (the default) means the result set is complete. A non-empty value is a human-readable explanation of why the producer could not complete the result set (e.g., query failure mid-evaluation).

SparqlStreamType

Type of a SPARQL result stream.

Name Number Description
SPARQL_STREAM_TYPE_FLAT 0 The entire stream is a single result set. This is the default. buf:lint:ignore ENUM_ZERO_VALUE_SUFFIX
SPARQL_STREAM_TYPE_PUNCTUATED 1 The stream is a sequence of result sets, each ended by a frame with a trailer. The lookup tables are kept from one result set to the next.

Scalar Value Types

.proto Type Notes C++ Java Python Go C# PHP Ruby
double double double float float64 double float Float
float float float float float32 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 int32 int integer Bignum or Fixnum (as required)
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 int64 long integer/string Bignum
uint32 Uses variable-length encoding. uint32 int int/long uint32 uint integer Bignum or Fixnum (as required)
uint64 Uses variable-length encoding. uint64 long int/long uint64 ulong integer/string Bignum or Fixnum (as required)
sint32 Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int32s. int32 int int int32 int integer Bignum or Fixnum (as required)
sint64 Uses variable-length encoding. Signed int value. These more efficiently encode negative numbers than regular int64s. int64 long int/long int64 long integer/string Bignum
fixed32 Always four bytes. More efficient than uint32 if values are often greater than 2^28. uint32 int int uint32 uint integer Bignum or Fixnum (as required)
fixed64 Always eight bytes. More efficient than uint64 if values are often greater than 2^56. uint64 long int/long uint64 ulong integer/string Bignum
sfixed32 Always four bytes. int32 int int int32 int integer Bignum or Fixnum (as required)
sfixed64 Always eight bytes. int64 long int/long int64 long integer/string Bignum
bool bool boolean boolean bool bool boolean TrueClass/FalseClass
string A string must always contain UTF-8 encoded or 7-bit ASCII text. string String str/unicode string string string String (UTF-8)
bytes May contain any arbitrary sequence of bytes. string ByteString str []byte ByteString string String (ASCII-8BIT)