Why my bash command is not found

devtoolmaker · April 11, 2023, 10:22am

I am experimenting with snap to execute bash commands and not able to get my head around why this doesn’t work.

Problem

The app is not able to execute xprop bash command. I installed the package using sudo snap install mysnap1.0.0-beta.snap --dangerous --devmode and tested by running it from the command line - $ mysnap, I see following error in my app’s logs

xprop not found

Debugging info

I have following debugging info but not able to judge where is the mistake

Here’s my snap.yaml as seen in /snap/<application>/current/meta

name: mysnap
version: 1.0.0-beta
summary: My Snap App
description: My little snap app
apps:
  mysnap:
    command: command.sh
    plugs:
    - desktop
    - desktop-legacy
    - home
    - x11
    - wayland
    - unity7
    - browser-support
    - network
    - gsettings
    - audio-playback
    - pulseaudio
    - opengl
    autostart: mysnap.desktop
    environment:
      DISABLE_WAYLAND: '1'
      PATH: $SNAP/usr/sbin:$SNAP/usr/bin:$SNAP/sbin:$SNAP/bin:$PATH
      SNAP_DESKTOP_RUNTIME: $SNAP/gnome-platform
      LD_LIBRARY_PATH: $SNAP_LIBRARY_PATH:$SNAP/lib:$SNAP/usr/lib:$SNAP/lib/x86_64-linux-gnu:$SNAP/usr/lib/x86_64-linux-gnu:$LD_LIBRARY_PATH:$SNAP/lib:$SNAP/usr/lib:$SNAP/lib/x86_64-linux-gnu:$SNAP/usr/lib/x86_64-linux-gnu
architectures:
- amd64
base: core18
confinement: devmode
grade: stable
plugs:
  gnome-3-28-1804:
    interface: content
    target: $SNAP/gnome-platform
    default-provider: gnome-3-28-1804
  gtk-3-themes:
    interface: content
    target: $SNAP/data-dir/themes
    default-provider: gtk-common-themes
  icon-themes:
    interface: content
    target: $SNAP/data-dir/icons
    default-provider: gtk-common-themes
  sound-themes:
    interface: content
    target: $SNAP/data-dir/sounds
    default-provider: gtk-common-themes
title: My Snap

The snappy-debug shows this on sudo snappy-debug

INFO: Following '/var/log/syslog'. If have dropped messages, use:
INFO: $ sudo journalctl --output=short --follow --all | sudo snappy-debug
kernel.printk_ratelimit = 0


= AppArmor =
Time: Apr 09 12:33:49
Log: apparmor="ALLOWED" operation="dbus_signal"  bus="session" path="/StatusNotifierItem" interface="org.freedesktop.DBus.Properties" member="PropertiesChanged" mask="send" name="org.freedesktop.DBus" pid=14146 label="snap.mysnap.mysnap" peer_pid=2256 peer_label="unconfined"
DBus access

And snap logs mysnap shows this

error: snap "mysnap" has no services

Note: The app works fine without any crashes otherwise. The only issue is with the bash command, that does not get executed.

ogra · April 11, 2023, 10:50am

your snap.yaml is just the result of processing the snapcraft.yaml file and is lacking all relevant information that could help here …

we’d need to see the original snapcraft.yaml that was used to produce the snap …

devtoolmaker · April 11, 2023, 12:33pm

I used electron-builder to package this. I am not sure if this is right file you are looking for but I did see this snapcraft.yaml file in a temporary folder created during the build process

base: core18
grade: stable
confinement: devmode
parts:
  launch-scripts:
    plugin: dump
    source: scripts
  gnome-platform-empty-dirs:
    plugin: nil
    override-build: |
      mkdir -p "$SNAPCRAFT_PART_INSTALL/data-dir/themes" mkdir -p "$SNAPCRAFT_PART_INSTALL/data-dir/icons" mkdir -p "$SNAPCRAFT_PART_INSTALL/data-dir/sounds" mkdir $SNAPCRAFT_PART_INSTALL/gnome-platform
  app-files:
    plugin: dump
    source: app
    organize:
      '*': app/
    stage:
      - '-app/chrome-sandbox'
      - '-LICENSES.chromium.html'
  app:
    plugin: nil
    stage:
      - '-usr/lib/python*'
      - '-usr/bin/python*'
      - '-var/lib/ucf'
      - '-usr/include'
      - '-usr/lib/X11'
      - '-usr/share'
      - '-usr/sbin'
      - '-usr/bin'
      - '-usr/lib/*/libicudata.*'
      - '-usr/lib/*/libicui18n.*'
      - '-usr/lib/*/libgtk-*'
      - '-usr/lib/*/libgdk-*'
      - '-usr/lib/*/glib-*'
      - '-usr/lib/*/gtk-*'
      - '-usr/lib/*/gdk-*'
      - '-usr/lib/*/krb5'
      - '-usr/lib/systemd'
      - '-usr/lib/glib-networking'
      - '-usr/lib/dconf'
      - '-usr/lib/*/avahi'
      - '-usr/lib/*/gio'
      - '-usr/lib/*/libatk*'
      - '-usr/lib/*/libatspi*'
      - '-usr/lib/*/libavahi*'
      - '-usr/lib/*/libcairo*'
      - '-usr/lib/*/libcolordprivate*'
      - '-usr/lib/*/libcolord*'
      - '-usr/lib/*/libcroco*'
      - '-usr/lib/*/libcups*'
      - '-usr/lib/*/libdatrie*'
      - '-usr/lib/*/libdconf*'
      - '-usr/lib/*/libepoxy*'
      - '-usr/lib/*/libexpatw*'
      - '-usr/lib/*/libffi*'
      - '-usr/lib/*/libfontconfig*'
      - '-usr/lib/*/libfreetype*'
      - '-usr/lib/*/libgdk_pixbuf*'
      - '-usr/lib/*/libgdk_pixbuf_xlib*'
      - '-usr/lib/*/libgio*'
      - '-usr/lib/*/libglib*'
      - '-usr/lib/*/libgmodule*'
      - '-usr/lib/*/libgmp*'
      - '-usr/lib/*/libgnutls*'
      - '-usr/lib/*/libgobject*'
      - '-usr/lib/*/libgraphite2*'
      - '-usr/lib/*/libgssapi_krb5*'
      - '-usr/lib/*/libgthread*'
      - '-usr/lib/*/libharfbuzz*'
      - '-usr/lib/*/libhogweed*'
      - '-usr/lib/*/libicuio*'
      - '-usr/lib/*/libicutest*'
      - '-usr/lib/*/libicutu*'
      - '-usr/lib/*/libicuuc*'
      - '-usr/lib/*/libidn2*'
      - '-usr/lib/*/libjbig*'
      - '-usr/lib/*/libjpeg*'
      - '-usr/lib/*/libjson*'
      - '-usr/lib/*/libk5crypto*'
      - '-usr/lib/*/libkrb5*'
      - '-usr/lib/*/libkrb5support*'
      - '-usr/lib/*/liblcms2*'
      - '-usr/lib/*/libnettle*'
      - '-usr/lib/*/libp11*'
      - '-usr/lib/*/libpango*'
      - '-usr/lib/*/libpangocairo*'
      - '-usr/lib/*/libpangoft2*'
      - '-usr/lib/*/libpixman*'
      - '-usr/lib/*/libpng16*'
      - '-usr/lib/*/libproxy*'
      - '-usr/lib/*/librest*'
      - '-usr/lib/*/librsvg*'
      - '-usr/lib/*/libsecret*'
      - '-usr/lib/*/libsoup*'
      - '-usr/lib/*/libsqlite3*'
      - '-usr/lib/*/libtasn1*'
      - '-usr/lib/*/libthai*'
      - '-usr/lib/*/libtiff*'
      - '-usr/lib/*/libunistring*'
      - '-usr/lib/*/libwayland*'
      - '-usr/lib/*/libX11*'
      - '-usr/lib/*/libXau*'
      - '-usr/lib/*/libxcb.so*'
      - '-usr/lib/*/libxcb-dri2*'
      - '-usr/lib/*/libxcb-dri3*'
      - '-usr/lib/*/libxcb-glx*'
      - '-usr/lib/*/libxcb-present*'
      - '-usr/lib/*/libxcb-render*'
      - '-usr/lib/*/libxcb-shm*'
      - '-usr/lib/*/libxcb-sync*'
      - '-usr/lib/*/libxcb-xfixes*'
      - '-usr/lib/*/libXcomposite*'
      - '-usr/lib/*/libXcursor*'
      - '-usr/lib/*/libXdamage*'
      - '-usr/lib/*/libXdmcp*'
      - '-usr/lib/*/libXext*'
      - '-usr/lib/*/libXfixes*'
      - '-usr/lib/*/libXinerama*'
      - '-usr/lib/*/libXi*'
      - '-usr/lib/*/libxkbcommon*'
      - '-usr/lib/*/libxml2*'
      - '-usr/lib/*/libXrandr*'
      - '-usr/lib/*/libXrender*'
    stage-packages:
      - x11-utils
      - libnspr4
      - libnss3
      - libxss1
      - libappindicator3-1
      - libsecret-1-0
plugs:
  gnome-3-28-1804:
    interface: content
    target: $SNAP/gnome-platform
    default-provider: gnome-3-28-1804
  gtk-3-themes:
    interface: content
    target: $SNAP/data-dir/themes
    default-provider: gtk-common-themes
  icon-themes:
    interface: content
    target: $SNAP/data-dir/icons
    default-provider: gtk-common-themes
  sound-themes:
    interface: content
    target: $SNAP/data-dir/sounds
    default-provider: gtk-common-themes
name: mysnap
version: 1.0.0-beta
title: My Snap
summary: My snap app
description: My little snap app
architectures:
  - amd64
apps:
  mysnap:
    command: command.sh
    plugs:
      - desktop
      - desktop-legacy
      - home
      - x11
      - wayland
      - unity7
      - browser-support
      - network
      - gsettings
      - audio-playback
      - pulseaudio
      - opengl
    adapter: none
    autostart: mysnap.desktop
    environment:
      DISABLE_WAYLAND: '1'
      PATH: $SNAP/usr/sbin:$SNAP/usr/bin:$SNAP/sbin:$SNAP/bin:$PATH
      SNAP_DESKTOP_RUNTIME: $SNAP/gnome-platform
      LD_LIBRARY_PATH: $SNAP_LIBRARY_PATH:$SNAP/lib:$SNAP/usr/lib:$SNAP/lib/x86_64-linux-gnu:$SNAP/usr/lib/x86_64-linux-gnu:$LD_LIBRARY_PATH:$SNAP/lib:$SNAP/usr/lib:$SNAP/lib/x86_64-linux-gnu:$SNAP/usr/lib/x86_64-linux-gnu
icon: snap/gui/icon.png

ogra · April 11, 2023, 12:37pm

well, whatever electron-builder generates here, it seems to wipe everything from usr/bin and usr/sbin …

devtoolmaker · April 11, 2023, 12:41pm

I see. So is this a bug in electron-builder or this could be an issue with the snap/multipass tooling? How do we go about fixing this?

ogra · April 11, 2023, 12:44pm

no idea, i have never used electron-builder (only electron-packager invoked from inside a snapcraft.yaml that i maintain myself) i’d check the snap content first, just use unsquashfs to extract it and take a look inside if xprop is really missing, if usr/bin or sbin are missing etc … if that’s the case i’d file an issue against electron-builder then

devtoolmaker · April 11, 2023, 3:19pm

I unpacked the snap unsquashfs, here’s the outcome

The /meta/snap.yaml is the same as we saw earlier at /snap/<application>/current/meta (the first message on this thread)
The usr folder has only lib folder. No other folders such as bin or sbin

ogra · April 11, 2023, 3:22pm

right, so you should open an electron-builder issue and ask why their generated snapcraft.yaml essentially removes all content of the stage-packages in the same part it seeds them … (this is really strange behavior and essentially makes the whole part a no-op)

devtoolmaker · April 11, 2023, 3:27pm

Too bad. There is similar issue reported on electron-builder in 2021, still open.

ogra · April 11, 2023, 3:32pm

ah, seems like a well known bug (it even has a link to the function doing it) …

perhaps you should consider going the electron-packager route ?

here is an example snap where i use electron-packager (it reads package.json, processes it and creates a binary blob that you can then just use inside the snap)

devtoolmaker · April 11, 2023, 3:44pm

Thank you. I packaged using npx electron-packager app and got the my app-linux-x64 folder. But how do we get it packaged as a snap?