<section 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-pkgs-appimageTools">
 <title>pkgs.appimageTools</title>

 <para>
  <varname>pkgs.appimageTools</varname> is a set of functions for extracting and wrapping <link xlink:href="https://appimage.org/">AppImage</link> files. They are meant to be used if traditional packaging from source is infeasible, or it would take too long. To quickly run an AppImage file, <literal>pkgs.appimage-run</literal> can be used as well.
 </para>

 <warning>
  <para>
   The <varname>appimageTools</varname> API is unstable and may be subject to backwards-incompatible changes in the future.
  </para>
 </warning>

 <section xml:id="ssec-pkgs-appimageTools-formats">
  <title>AppImage formats</title>

  <para>
   There are different formats for AppImages, see <link xlink:href="https://github.com/AppImage/AppImageSpec/blob/74ad9ca2f94bf864a4a0dac1f369dd4f00bd1c28/draft.md#image-format">the specification</link> for details.
  </para>

  <itemizedlist>
   <listitem>
    <para>
     Type 1 images are ISO 9660 files that are also ELF executables.
    </para>
   </listitem>
   <listitem>
    <para>
     Type 2 images are ELF executables with an appended filesystem.
    </para>
   </listitem>
  </itemizedlist>

  <para>
   They can be told apart with <command>file -k</command>:
  </para>

<screen>
<prompt>$ </prompt>file -k type1.AppImage
type1.AppImage: ELF 64-bit LSB executable, x86-64, version 1 (SYSV) ISO 9660 CD-ROM filesystem data 'AppImage' (Lepton 3.x), scale 0-0,
spot sensor temperature 0.000000, unit celsius, color scheme 0, calibration: offset 0.000000, slope 0.000000, dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.18, BuildID[sha1]=d629f6099d2344ad82818172add1d38c5e11bc6d, stripped\012- data

<prompt>$ </prompt>file -k type2.AppImage
type2.AppImage: ELF 64-bit LSB executable, x86-64, version 1 (SYSV) (Lepton 3.x), scale 232-60668, spot sensor temperature -4.187500, color scheme 15, show scale bar, calibration: offset -0.000000, slope 0.000000 (Lepton 2.x), scale 4111-45000, spot sensor temperature 412442.250000, color scheme 3, minimum point enabled, calibration: offset -75402534979642766821519867692934234112.000000, slope 5815371847733706829839455140374904832.000000, dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 2.6.18, BuildID[sha1]=79dcc4e55a61c293c5e19edbd8d65b202842579f, stripped\012- data
</screen>

  <para>
   Note how the type 1 AppImage is described as an <literal>ISO 9660 CD-ROM filesystem</literal>, and the type 2 AppImage is not.
  </para>
 </section>

 <section xml:id="ssec-pkgs-appimageTools-wrapping">
  <title>Wrapping</title>

  <para>
   Depending on the type of AppImage you're wrapping, you'll have to use <varname>wrapType1</varname> or <varname>wrapType2</varname>.
  </para>

<programlisting>
appimageTools.wrapType2 { # or wrapType1
  name = "patchwork"; <co xml:id='ex-appimageTools-wrapping-1' />
  src = fetchurl { <co xml:id='ex-appimageTools-wrapping-2' />
    url = https://github.com/ssbc/patchwork/releases/download/v3.11.4/Patchwork-3.11.4-linux-x86_64.AppImage;
    sha256 =  "1blsprpkvm0ws9b96gb36f0rbf8f5jgmw4x6dsb1kswr4ysf591s";
  };
  extraPkgs = pkgs: with pkgs; [ ]; <co xml:id='ex-appimageTools-wrapping-3' />
}</programlisting>

  <calloutlist>
   <callout arearefs='ex-appimageTools-wrapping-1'>
    <para>
     <varname>name</varname> specifies the name of the resulting image.
    </para>
   </callout>
   <callout arearefs='ex-appimageTools-wrapping-2'>
    <para>
     <varname>src</varname> specifies the AppImage file to extract.
    </para>
   </callout>
   <callout arearefs='ex-appimageTools-wrapping-2'>
    <para>
     <varname>extraPkgs</varname> allows you to pass a function to include additional packages inside the FHS environment your AppImage is going to run in. There are a few ways to learn which dependencies an application needs:
     <itemizedlist>
      <listitem>
       <para>
        Looking through the extracted AppImage files, reading its scripts and running <command>patchelf</command> and <command>ldd</command> on its executables. This can also be done in <command>appimage-run</command>, by setting <command>APPIMAGE_DEBUG_EXEC=bash</command>.
       </para>
      </listitem>
      <listitem>
       <para>
        Running <command>strace -vfefile</command> on the wrapped executable, looking for libraries that can't be found.
       </para>
      </listitem>
     </itemizedlist>
    </para>
   </callout>
  </calloutlist>
 </section>
</section>
