binary-cache: read narinfos with harmonia's parser#1793
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| // only accepts the base name. Parsing via the store | ||
| // directory (assumed to be the default one throughout this | ||
| // function) also rejects narinfos for a different store. | ||
| store_path_opt = Some(StoreDir::default().parse(val).map_err( |
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Fine for hydra.nixos.org, but the StoreDir here ought to be a parameter that we pass in.
(Also presumably this parsing logic is in Harmonia?)
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nix-community/harmonia#1080 the logic is in Harmonia now (asked @amaanq to write from scratch)
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The `StorePath` field of a narinfo holds the full path (`/nix/store/<hash>-<name>`); cache.nixos.org serves it that way and `harmonia_store_nar_info`, used for our own uploads, writes it that way. Our hand-rolled `parse_narinfo` fed the value into `StorePath::from_str`, which only accepts the base name, so every spec-conforming narinfo failed to parse. The queue runner therefore could not read back narinfos from its own binary cache: `has_narinfo` failed for every path, uploads were repeated endlessly and `copy_paths` errors failed the affected builds. Observed on a 120-build nixos-small evaluation against an S3 cache populated by the runner itself: 2067 `invalid value for StorePath` errors and all 120 builds failing with status 2. harmonia has since grown its own `parse_narinfo_txt` (mirroring nix's `nar-info.cc`), so delegate to it instead of maintaining our own. It takes the store directory explicitly, so carry it on `S3CacheConfig`, read from the `store` query parameter of the cache URL (the nix S3 convention, defaulting to `/nix/store`); both the upload and download paths now use `self.cfg.store_dir` rather than threading it in. Besides reading `StorePath` as a full path, this also fixes two ways our parser diverged from nix: `Deriver: unknown-deriver` and an optional `Compression` field.
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The
StorePathfield of a narinfo holds the full path(
/nix/store/<hash>-<name>); cache.nixos.org serves it that way andharmonia_store_nar_info, used for our own uploads, writes it that way.Our hand-rolled
parse_narinfofed the value intoStorePath::from_str,which only accepts the base name, so every spec-conforming narinfo failed
to parse.
The queue runner therefore could not read back narinfos from its own
binary cache:
has_narinfofailed for every path, uploads were repeatedendlessly and
copy_pathserrors failed the affected builds. Observed ona 120-build nixos-small evaluation against an S3 cache populated by the
runner itself: 2067
invalid value for StorePatherrors and all 120builds failing with status 2.
harmonia has since grown its own
parse_narinfo_txt(mirroring nix'snar-info.cc), so delegate to it instead of maintaining our own. It takesthe store directory explicitly, so carry it on
S3CacheConfig, read fromthe
storequery parameter of the cache URL (the nix S3 convention,defaulting to
/nix/store); both the upload and download paths now useself.cfg.store_dirrather than threading it in. Besides readingStorePathas a full path, this also fixes two ways our parser divergedfrom nix:
Deriver: unknown-deriverand an optionalCompressionfield.