Module ldp 

Linked Data Platform (LDP) resource and container semantics.

Phase 2 scope:

• Full Link header set (type + acl + describedby + storage root).
• Prefer header parsing (PreferMinimalContainer, PreferContainedIRIs).
• Accept-Post header for containers.
• PATCH via N3 (solid-protocol PATCH): insert, delete, where.
• PATCH via SPARQL-Update (INSERT DATA, DELETE DATA, DELETE WHERE).
• Content negotiation: Turtle, JSON-LD, N-Triples, RDF/XML.
• Server-managed triples (dc:modified, stat:size, ldp:contains).
• .meta sidecar resolution.

The module intentionally uses a tiny, in-crate RDF triple model so the crate stays free of the heavier sophia / oxigraph dep trees. Only Turtle-subset parsing required for real-world Solid Pod PATCH flows is supported; client-supplied RDF is parsed via the N-Triples fallback whenever the Turtle fast path hits something exotic.

Modules

iri

Well-known IRI constants used in LDP, WAC, and server-managed triples.

Structs

ByteRange

A parsed byte range. end is inclusive per RFC 7233 §2.1.

ContainerMember

Graph

Minimal RDF graph — a sorted set of triples.

OptionsResponse

Build the set of values returned on OPTIONS for a Solid resource.

PatchOutcome

Outcome of evaluating a PATCH request.

PreferHeader

Parsed Prefer header value. Non-return=representation preferences are ignored (the LDP spec allows this).

Triple

Enums

ConditionalOutcome

Outcome of evaluating conditional request headers against a current resource ETag.

ContainerRepresentation

What portions of a container representation the client wants.

PatchCreateOutcome

Outcome of applying a PATCH to a path that had no prior resource.

PatchDialect

Pick a PATCH dialect from the Content-Type header.

RangeOutcome

Outcome of evaluating Range: against a known resource length. Full → 200 (no Range: header); Partial → 206; NotSatisfiable → 416 (not 412, which the old parse_range_header conflated).

RdfFormat

Term

Constants

ACCEPT_PATCH

Accept-Patch advertising the PATCH dialects supported.

ACCEPT_POST

MIME types recognised by the content negotiator. The order matters: the first format that matches the Accept header wins, and if the client provides */* the server defaults to Turtle.

CACHE_CONTROL_RDF

RFC 7234 Cache-Control directive for RDF response variants.

MAX_SLUG_BYTES

Maximum byte length of a client-supplied Slug header. JSS caps at 255 bytes (POSIX filename limit); we match for interop.

SERVER_MANAGED_PREDICATES

List of predicates clients are not allowed to set directly. These are overwritten by the server on PUT.

Traits

LdpContainerOps

Functions

apply_json_patch

Apply a JSON Patch document (RFC 6902) to a serde_json::Value in place. Returns Err(PodError::PreconditionFailed) when a test operation fails, Err(PodError::Unsupported) for malformed patches.

apply_n3_patch

Apply a solid-protocol N3 PATCH document to target.

apply_patch_to_absent

Apply a PATCH document to an absent resource by seeding an empty graph and running the dialect-specific patcher. JSON Patch is unsupported in this path.

apply_sparql_patch

Apply a SPARQL 1.1 Update document (INSERT DATA, DELETE DATA, DELETE WHERE) to target using spargebra for parsing.

cache_control_for

Return the Cache-Control header value appropriate for a response of the supplied content_type, or None to leave the header unset. RDF variants always get CACHE_CONTROL_RDF; non-RDF payloads (binary blobs, images, etc.) are left to caller policy.

evaluate_preconditions

Evaluate If-Match and If-None-Match precondition headers against the current ETag of a resource. The caller passes whatever is observed on the storage side; None for the ETag means the resource does not exist.

find_illegal_server_managed

Return the list of client-supplied triples that attempt to set server-managed predicates. These MUST be ignored at PUT time.

infer_dotfile_content_type

Infer a content-type for auxiliary “dotfile” resources (.acl, .meta, and their *.acl / *.meta suffix variants) whose extension-based lookup would otherwise fail.

is_acl_path

Return whether a path addresses an ACL sidecar.

is_container

Return whether a path addresses an LDP container.

is_meta_path

Return whether a path addresses a .meta sidecar.

is_rdf_content_type

Return true if content_type identifies an RDF serialisation the server emits through content negotiation or stores natively. Matches the formats advertised in ACCEPT_POST plus text/n3 and application/trig (JSS parity). Parameters (e.g. ; charset=utf-8) are tolerated.

link_headers

Build the full set of Link headers for a given resource path.

meta_sidecar_for

Compute the .meta sidecar for a resource.

negotiate_format

Pick the best RDF format based on an Accept header.

not_found_headers

Build the header set returned on 404 Not Found for an LDP path.

options_for

parse_range_header

Parse a Range: header value of the form bytes=start-end or bytes=start- or bytes=-suffix. Multi-range is intentionally not supported — Solid Pods treat non-rangeable media (JSON-LD, Turtle) as opaque and the binary path is the only consumer.

parse_range_header_v2

JSS-parity range parser. Same grammar as parse_range_header but maps “empty body + header present” and “range past end” to NotSatisfiable. Malformed headers still return Err so callers can reply 400.

patch_dialect_from_mime

render_container

Backwards-compatible alias for the Phase 1 API.

render_container_jsonld

Render a container as JSON-LD respecting a Prefer header.

render_container_turtle

Render a container as Turtle.

resolve_slug

Resolve the target path when POSTing to a container.

server_managed_triples

Compute the server-managed triples for a resource (dc:modified, stat:size, and for containers ldp:contains entries).

slice_range

Slice a body buffer to a byte range. The slice is a zero-copy view; callers are expected to copy_from_slice or similar when returning it through an HTTP framework.

vary_header

Value of the Vary: header depending on whether content negotiation is enabled. Authorization and Origin are always listed so shared caches never collapse an authenticated and an anonymous response onto the same cache entry.