diff --git a/doc/manual/src/command-ref/nix-store/realise.md b/doc/manual/src/command-ref/nix-store/realise.md index c19aea75e..a421a4220 100644 --- a/doc/manual/src/command-ref/nix-store/realise.md +++ b/doc/manual/src/command-ref/nix-store/realise.md @@ -1,6 +1,6 @@ # Name -`nix-store --realise` - realise specified store paths +`nix-store --realise` - build or fetch store objects # Synopsis @@ -8,33 +8,35 @@ # Description -The operation `--realise` essentially “builds” the specified store -paths. Realisation is a somewhat overloaded term: - - If the store path is a *derivation*, realisation ensures that the - output paths of the derivation are [valid] (i.e., - the output path and its closure exist in the file system). This - can be done in several ways. First, it is possible that the - outputs are already valid, in which case we are done - immediately. Otherwise, there may be [substitutes] - that produce the outputs (e.g., by downloading them). Finally, the - outputs can be produced by running the build task described - by the derivation. +Each of *paths* is processed as follows: - - If the store path is not a derivation, realisation ensures that the - specified path is valid (i.e., it and its closure exist in the file - system). If the path is already valid, we are done immediately. - Otherwise, the path and any missing paths in its closure may be - produced through substitutes. If there are no (successful) - substitutes, realisation fails. +- If the path leads to a [store derivation]: + 1. If it is not [valid], substitute the store derivation file itself. + 2. Realise its [output paths]: + - Try to fetch from [substituters] the [store objects] associated with the output paths in the store derivation's [closure]. + - With [content-addressed derivations] (experimental): Determine the output paths to realise by querying content-addressed realisation entries in the [Nix database]. + - For any store paths that cannot be substituted, produce the required store objects. This involves first realising all outputs of the derivation's dependencies and then running the derivation's [`builder`](@docroot@/language/derivations.md#attr-builder) executable. +- Otherwise, and if the path is not already valid: Try to fetch the associated [store objects] in the path's [closure] from [substituters]. +If no substitutes are available and no store derivation is given, realisation fails. + +[store paths]: @docroot@/glossary.md#gloss-store-path [valid]: @docroot@/glossary.md#gloss-validity -[substitutes]: @docroot@/glossary.md#gloss-substitute +[store derivation]: @docroot@/glossary.md#gloss-store-derivation +[output paths]: @docroot@/glossary.md#gloss-output-path +[store objects]: @docroot@/glossary.md#gloss-store-object +[closure]: @docroot@/glossary.md#gloss-closure +[substituters]: @docroot@/command-ref/conf-file.md#conf-substituters +[content-addressed derivations]: @docroot@/contributing/experimental-features.md#xp-feature-ca-derivations +[Nix database]: @docroot@/glossary.md#gloss-nix-database -The output path of each derivation is printed on standard output. (For -non-derivations argument, the argument itself is printed.) +The resulting paths are printed on standard output. +For non-derivation arguments, the argument itself is printed. -The following flags are available: +{{#include ../status-build-failure.md}} + +# Options - `--dry-run`\ Print on standard error a description of what packages would be @@ -54,8 +56,6 @@ The following flags are available: previous build, the new output path is left in `/nix/store/name.check.` -{{#include ../status-build-failure.md}} - {{#include ./opt-common.md}} {{#include ../opt-common.md}} @@ -67,8 +67,6 @@ The following flags are available: This operation is typically used to build [store derivation]s produced by [`nix-instantiate`](@docroot@/command-ref/nix-instantiate.md): -[store derivation]: @docroot@/glossary.md#gloss-store-derivation - ```console $ nix-store --realise $(nix-instantiate ./test.nix) /nix/store/31axcgrlbfsxzmfff1gyj1bf62hvkby2-aterm-2.3.1 diff --git a/doc/manual/src/glossary.md b/doc/manual/src/glossary.md index d950a4ca8..57a3334dd 100644 --- a/doc/manual/src/glossary.md +++ b/doc/manual/src/glossary.md @@ -33,7 +33,7 @@ Ensure a [store path] is [valid][validity]. - This means either running the `builder` executable as specified in the corresponding [derivation] or fetching a pre-built [store object] from a [substituter]. + This means either running the [`builder`](@docroot@/language/derivations.md#attr-builder) executable as specified in the corresponding [derivation], or fetching a pre-built [store object] from a [substituter], or delegating to a [remote builder](@docroot@/advanced-topics/distributed-builds.html) and retrieving the outputs. See [`nix-build`](./command-ref/nix-build.md) and [`nix-store --realise`](@docroot@/command-ref/nix-store/realise.md). diff --git a/doc/manual/src/language/derivations.md b/doc/manual/src/language/derivations.md index 043a38191..79a09122a 100644 --- a/doc/manual/src/language/derivations.md +++ b/doc/manual/src/language/derivations.md @@ -17,7 +17,7 @@ the attributes of which specify the inputs of the build. string. This is used as a symbolic name for the package by `nix-env`, and it is appended to the output paths of the derivation. - - There must be an attribute named `builder` that identifies the + - There must be an attribute named [`builder`]{#attr-builder} that identifies the program that is executed to perform the build. It can be either a derivation or a source (a local file reference, e.g., `./builder.sh`).