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6 commits

Author SHA1 Message Date
regnat e69cfdebb0 Remove the visit machinery in RealisedPath
In addition to being some ugly template trickery, it was also totally
useless as it was used in only one place where I could replace it by
just a few extra characters
2021-02-05 11:42:33 +01:00
Théophane Hufschmitt 43d409f669
Fix a whitespace issue
Co-authored-by: Eelco Dolstra <edolstra@gmail.com>
2021-02-04 14:47:56 +01:00
regnat 9355ecd543 Add a new Cmd type working on RealisedPaths
Where a `RealisedPath` is a store path with its history, meaning either
an opaque path for stuff that has been directly added to the store, or a
`Realisation` for stuff that has been built by a derivation

This is a low-level refactoring that doesn't bring anything by itself
(except a few dozen extra lines of code :/ ), but raising the
abstraction level a bit is important on a number of levels:

- Commands like `nix build` have to query for the realisations after the
  build is finished which is fragile (see
  27905f12e4a7207450abe37c9ed78e31603b67e1 for example). Having them
  oprate directly at the realisation level would avoid that
- Others like `nix copy` currently operate directly on (built) store
  paths, but need a bit more information as they will need to register
  the realisations on the remote side
2021-01-28 09:38:44 +01:00
regnat bab1cda0e6 Use the hash modulo in the derivation outputs
Rather than storing the derivation outputs as `drvPath!outputName` internally,
store them as `drvHashModulo!outputName` (or `outputHash!outputName` for
fixed-output derivations).

This makes the storage slightly more opaque, but enables an earlier
cutoff in cases where a fixed-output dependency changes (but keeps the
same output hash) − same as what we already do for input-addressed
derivations.
2020-12-11 21:17:23 +01:00
regnat 8914e01e37 Store the realisations as JSON in the binary cache
Fix #4332
2020-12-11 21:05:09 +01:00
regnat 58cdab64ac Store metadata about drv outputs realisations
For each known realisation, store:
- its output
- its output path

This comes with a set of needed changes:

- New `realisations` module declaring the types needed for describing
  these mappings
- New `Store::registerDrvOutput` method registering all the needed informations
  about a derivation output (also replaces `LocalStore::linkDeriverToPath`)
- new `Store::queryRealisation` method to retrieve the informations for a
  derivations

This introcudes some redundancy on the remote-store side between
`wopQueryDerivationOutputMap` and `wopQueryRealisation`.
However we might need to keep both (regardless of backwards compat)
because we sometimes need to get some infos for all the outputs of a
derivation (where `wopQueryDerivationOutputMap` is handy), but all the
stores can't implement it − because listing all the outputs of a
derivation isn't really possible for binary caches where the server
doesn't allow to list a directory.
2020-12-11 20:41:32 +01:00