Struct FetchPaperOutcome 

#[non_exhaustive]
pub struct FetchPaperOutcome {
    pub source: String,
    pub resolver_profile: String,
    pub license: String,
    pub path: Utf8PathBuf,
    pub size_bytes: u64,
    pub schema_version: String,
    pub pdf_leg: PdfLegStatus,
    pub safekey: String,
    pub canonical_digest: String,
}

What fetch_paper wrote to disk and how.

path is the PDF (<root>/<safekey>.pdf) on a successful PDF fetch, or the metadata TOML (<root>/.metadata/<safekey>.toml) when the DOI path fell back to metadata-only. Self::pdf_leg disambiguates why there is no PDF (genuinely none available vs. available-but-blocked) so callers never report a blocked PDF as a silent success (issue #118).

Fields (Non-exhaustive)

Non-exhaustive structs could have additional fields added in future. Therefore, non-exhaustive structs cannot be constructed in external crates using the traditional Struct { .. } syntax; cannot be matched against without a wildcard ..; and struct update syntax will not work.

source: String

Source::name() of the resolver whose payload landed on disk: "arxiv" for an arXiv ref, "oa-publisher" when the DOI OA PDF leg succeeded, or "crossref" / "unpaywall" when the DOI path fell back to metadata-only. Mirrors the value written to [doiget].source in the metadata TOML.

resolver_profile: String

Resolver profile under which the canonical-digest (ADR-0021 §1) was minted for the final artifact. For an arXiv fetch this is "arxiv"; for a successful DOI OA PDF leg this is "oa-publisher"; for the DOI metadata-only fallback this is the metadata source key ("crossref" / "unpaywall"). Equal to Self::source verbatim in Slice 4 but kept distinct so future slices can decouple “which resolver wrote to disk” from “which resolver is the audit identity”. Surfaced through the doiget_fetch_paper MCP envelope per ADR-0021 §4.

license: String

OA license string ("CC-BY-4.0", "cc-by", "arxiv-default", "unknown"). Mirrors [doiget].license.

path: Utf8PathBuf

Absolute path of the artifact actually written (<root>/<safekey>.pdf on success, <root>/.metadata/<safekey>.toml on metadata-only fallback).

size_bytes: u64

Stored PDF size in bytes; 0 on the metadata-only fallback (docs/REDIRECT_ALLOWLIST.md §3.5).

schema_version: String

The schema version of the metadata TOML written (always crate::SCHEMA_VERSION for this build).

pdf_leg: PdfLegStatus

What happened on the PDF leg (issue #118). Fetched / NoOaUrl are clean outcomes; Blocked carries the structured reason an OA PDF existed but could not be retrieved, so the CLI / MCP surface it instead of a silent metadata-only success.

safekey: String

Per-ref crate::Safekey stringified (Ref::safekey().as_str()). Exposed on the outcome so JSON-mode CLI / MCP callers can emit a structured success body without re-parsing the input ref (#210 / docs/ERRORS.md §3). Always populated.

canonical_digest: String

ADR-0021 §1 canonical-digest as 64-char lowercase hex for the resolver_profile that produced this outcome’s audit identity. For an arXiv fetch this is the digest under "arxiv"; for a DOI OA PDF leg this is under "oa-publisher"; for the DOI metadata-only fallback this is under the metadata source key ("crossref" / "unpaywall"). Always populated.

Trait Implementations

impl Clone for FetchPaperOutcome

fn clone(&self) -> FetchPaperOutcome

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for FetchPaperOutcome

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.