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diff --git a/doc/manual/nix-push.xml b/doc/manual/nix-push.xml deleted file mode 100644 index e789bbf7d3..0000000000 --- a/doc/manual/nix-push.xml +++ /dev/null @@ -1,398 +0,0 @@ -<refentry xmlns="http://docbook.org/ns/docbook" - xmlns:xlink="http://www.w3.org/1999/xlink" - xmlns:xi="http://www.w3.org/2001/XInclude" - xml:id="sec-nix-push"> - -<refmeta> - <refentrytitle>nix-push</refentrytitle> - <manvolnum>1</manvolnum> - <refmiscinfo class="source">Nix</refmiscinfo> - <refmiscinfo class="version"><xi:include href="version.txt" parse="text"/></refmiscinfo> -</refmeta> - -<refnamediv> - <refname>nix-push</refname> - <refpurpose>generate a binary cache</refpurpose> -</refnamediv> - -<refsynopsisdiv> - <cmdsynopsis> - <command>nix-push</command> - <arg choice='plain'><option>--dest</option> <replaceable>dest-dir</replaceable></arg> - <arg><option>--bzip2</option></arg> - <arg><option>--none</option></arg> - <arg><option>--force</option></arg> - <arg><option>--link</option></arg> - <arg><option>--manifest</option></arg> - <arg><option>--manifest-path</option> <replaceable>filename</replaceable></arg> - <arg><option>--url-prefix</option> <replaceable>url</replaceable></arg> - <arg choice='plain' rep='repeat'><replaceable>paths</replaceable></arg> - </cmdsynopsis> -</refsynopsisdiv> - - -<refsection><title>Description</title> - -<para>The command <command>nix-push</command> produces a -<emphasis>binary cache</emphasis>, a directory containing compressed -Nix archives (NARs) plus some metadata of the closure of the specified -store paths. This directory can then be made available through a web -server to other Nix installations, allowing them to skip building from -source and instead download binaries from the cache -automatically.</para> - -<para><command>nix-push</command> performs the following actions. - -<orderedlist> - - <listitem><para>Each path in <replaceable>paths</replaceable> is - built (using <link - linkend='rsec-nix-store-realise'><command>nix-store - --realise</command></link>).</para></listitem> - - <listitem><para>All paths in the closure of - <replaceable>paths</replaceable> are determined (using - <command>nix-store --query --requisites - --include-outputs</command>). Note that since the - <option>--include-outputs</option> flag is used, if - <replaceable>paths</replaceable> includes a store derivation, you - get a combined source/binary distribution (e.g., source tarballs - will be included).</para></listitem> - - <listitem><para>All store paths determined in the previous step are - packaged into a NAR (using <command>nix-store --dump</command>) and - compressed using <command>xz</command> or <command>bzip2</command>. - The resulting files have the extension <filename>.nar.xz</filename> - or <filename>.nar.bz2</filename>. Also for each store path, Nix - generates a file with extension <filename>.narinfo</filename> - containing metadata such as the references, cryptographic hash and - size of each path.</para></listitem> - - <listitem><para>Optionally, a single <emphasis>manifest</emphasis> - file is created that contains the same metadata as the - <filename>.narinfo</filename> files. This is for compatibility with - Nix versions prior to 1.2 (see <command>nix-pull</command> for - details).</para></listitem> - - <listitem><para>A file named <option>nix-cache-info</option> is - placed in the destination directory. The existence of this file - marks the directory as a binary cache.</para></listitem> - -</orderedlist> - -</para> - -</refsection> - - -<refsection><title>Options</title> - -<variablelist> - - <varlistentry><term><option>--dest</option> <replaceable>dest-dir</replaceable></term> - - <listitem><para>Set the destination directory to - <replaceable>dir</replaceable>, which is created if it does not - exist. This flag is required.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--bzip2</option></term> - - <listitem><para>Compress NARs using <command>bzip2</command> - instead of <command>xz -9</command>. The latter compresses about - 30% better on typical archives, decompresses about twice as fast, - but compresses a lot slower and is not supported by Nix prior to - version 1.2.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--none</option></term> - - <listitem><para>Do not compress NARs.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--force</option></term> - - <listitem><para>Overwrite <filename>.narinfo</filename> files if - they already exist.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--link</option></term> - - <listitem><para>By default, NARs are generated in the Nix store - and then copied to <replaceable>dest-dir</replaceable>. If this - option is given, hard links are used instead. This only works if - <replaceable>dest-dir</replaceable> is on the same filesystem as - the Nix store.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--manifest</option></term> - - <listitem><para>Force the generation of a manifest suitable for - use by <command>nix-pull</command>. The manifest is stored as - <filename><replaceable>dest-dir</replaceable>/MANIFEST</filename>.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--manifest-path</option> <replaceable>filename</replaceable></term> - - <listitem><para>Like <option>--manifest</option>, but store the - manifest in <replaceable>filename</replaceable>.</para></listitem> - - </varlistentry> - - <varlistentry><term><option>--url-prefix</option> <replaceable>url</replaceable></term> - - <listitem><para>Manifests are expected to contain the absolute - URLs of NARs. For generating these URLs, the prefix - <replaceable>url</replaceable> is used. It defaults to - <uri>file://<replaceable>dest-dir</replaceable></uri>.</para></listitem> - - </varlistentry> - -</variablelist> - -</refsection> - - -<refsection><title>Examples</title> - -<para>To add the closure of Thunderbird to a binary cache: - -<screen> -$ nix-push --dest /tmp/cache $(nix-build -A thunderbird) -</screen> - -Assuming that <filename>/tmp/cache</filename> is exported by a web -server as <uri>http://example.org/cache</uri>, you can then use this -cache on another machine to speed up the installation of Thunderbird: - -<screen> -$ nix-build -A thunderbird --option binary-caches http://example.org/cache -</screen> - -Alternatively, you could add <literal>binary-caches = -http://example.org/cache</literal> to -<filename>nix.conf</filename>.</para> - -<para>To also include build-time dependencies (such as source -tarballs): - -<screen> -$ nix-push --dest /tmp/cache $(nix-instantiate -A thunderbird) -</screen> - -</para> - -<para>To generate a manifest suitable for <command>nix-pull</command>: - -<screen> -$ nix-push --dest /tmp/cache $(nix-build -A thunderbird) --manifest -</screen> - -On another machine you can then do: - -<screen> -$ nix-pull http://example.org/cache -</screen> - -to cause the binaries to be used by subsequent Nix operations.</para> - -</refsection> - - -<refsection><title>Binary cache format and operation</title> - -<para>A binary cache with URL <replaceable>url</replaceable> only -denotes a valid binary cache if the file -<uri><replaceable>url</replaceable>/nix-cache-info</uri> exists. If -this file does not exist (or cannot be downloaded), the cache is -ignored. If it does exist, it must be a text file containing cache -properties. Here’s an example: - -<screen> -StoreDir: /nix/store -WantMassQuery: 1 -Priority: 10 -</screen> - -The properties that are currently supported are: - -<variablelist> - - <varlistentry><term><literal>StoreDir</literal></term> - - <listitem><para>The path of the Nix store to which this binary - cache applies. Binaries are not relocatable — a binary built for - <filename>/nix/store</filename> won’t generally work in - <filename>/home/alice/store</filename> — so to prevent binaries - from being used in a wrong store, a binary cache is only used if - its <literal>StoreDir</literal> matches the local Nix - configuration. The default is - <filename>/nix/store</filename>.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>WantMassQuery</literal></term> - - <listitem><para>Query operations such as <command>nix-env - -qas</command> can cause thousands of cache queries, and thus - thousands of HTTP requests, to determine which packages are - available in binary form. While these requests are small, not - every server may appreciate a potential onslaught of queries. If - <literal>WantMassQuery</literal> is set to <literal>0</literal> - (default), “mass queries” such as <command>nix-env -qas</command> - will skip this cache. Thus a package may appear not to have a - binary substitute. However, the binary will still be used when - you actually install the package. If - <literal>WantMassQuery</literal> is set to <literal>1</literal>, - mass queries will use this cache.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>Priority</literal></term> - - <listitem><para>Each binary cache has a priority (defaulting to - 50). Binary caches are checked for binaries in order of ascending - priority; thus a higher number denotes a lower priority. The - binary cache <uri>http://cache.nixos.org</uri> has priority - 40.</para></listitem> - - </varlistentry> - -</variablelist> - -</para> - -<para>Every time Nix needs to build some store path -<replaceable>p</replaceable>, it will check each configured binary -cache to see if it has a NAR file for <replaceable>p</replaceable>, -until it finds one. If no cache has a NAR, Nix will fall back to -building the path from source (if applicable). To see if a cache with -URL <replaceable>url</replaceable> has a binary for -<replaceable>p</replaceable>, Nix fetches -<replaceable>url/h</replaceable>, where <replaceable>h</replaceable> -is the hash part of <replaceable>p</replaceable>. Thus, if we have a -cache <uri>http://cache.nixos.org</uri> and we want to obtain -the store path -<screen> -/nix/store/a8922c0h87iilxzzvwn2hmv8x210aqb9-glibc-2.7 -</screen> -then Nix will attempt to fetch -<screen> -http://cache.nixos.org/a8922c0h87iilxzzvwn2hmv8x210aqb9.narinfo -</screen> -(Commands such as <command>nix-env -qas</command> will issue an HTTP -HEAD request, since it only needs to know if the -<filename>.narinfo</filename> file exists.) The -<filename>.narinfo</filename> file is a simple text file that looks -like this: - -<screen> -StorePath: /nix/store/a8922c0h87iilxzzvwn2hmv8x210aqb9-glibc-2.7 -URL: nar/0zzjpdz46mdn74v09m053yczlz4am038g8r74iy8w43gx8801h70.nar.bz2 -Compression: bzip2 -FileHash: sha256:0zzjpdz46mdn74v09m053yczlz4am038g8r74iy8w43gx8801h70 -FileSize: 24473768 -NarHash: sha256:0s491y1h9hxj5ghiizlxk7ax6jwbha00zwn7lpyd5xg5bhf60vzg -NarSize: 109521136 -References: 2ma2k0ys8knh4an48n28vigcmc2z8773-linux-headers-2.6.23.16 ... -Deriver: 7akyyc87ka32xwmqza9dvyg5pwx3j212-glibc-2.7.drv -</screen> - -The fields are as follows: - -<variablelist> - - <varlistentry><term><literal>StorePath</literal></term> - - <listitem><para>The full store path, including the name part - (e.g., <literal>glibc-2.7</literal>). It must match the - requested store path.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>URL</literal></term> - - <listitem><para>The URL of the NAR, relative to the binary cache - URL.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>Compression</literal></term> - - <listitem><para>The compression method; either - <literal>xz</literal> or - <literal>bzip2</literal>.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>FileHash</literal></term> - - <listitem><para>The SHA-256 hash of the compressed - NAR.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>FileSize</literal></term> - - <listitem><para>The size of the compressed NAR.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>NarHash</literal></term> - - <listitem><para>The SHA-256 hash of the uncompressed NAR. This is - equal to the hash of the store path as returned by - <command>nix-store -q --hash - <replaceable>p</replaceable></command>.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>NarSize</literal></term> - - <listitem><para>The size of the uncompressed NAR.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>References</literal></term> - - <listitem><para>The references of the store path, without the Nix - store prefix.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>Deriver</literal></term> - - <listitem><para>The deriver of the store path, without the Nix - store prefix. This field is optional.</para></listitem> - - </varlistentry> - - <varlistentry><term><literal>System</literal></term> - - <listitem><para>The Nix platform type of this binary, if known. - This field is optional.</para></listitem> - - </varlistentry> - -</variablelist> - -</para> - -<para>Thus, in our example, after recursively ensuring that the -references exist (e.g., -<filename>/nix/store/2ma2k0ys8knh4an48n28vigcmc2z8773-linux-headers-2.6.23.16</filename>), -Nix will fetch <screen> -http://cache.nixos.org/nar/0zzjpdz46mdn74v09m053yczlz4am038g8r74iy8w43gx8801h70.nar.bz2 -</screen> and decompress and unpack it to -<filename>/nix/store/a8922c0h87iilxzzvwn2hmv8x210aqb9-glibc-2.7</filename>.</para> - -</refsection> - - -</refentry> |