Graphical Snaps for Ubuntu Core #755
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…torials.ubuntu.com into graphical-snaps
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User is not a collaborator of this repo. Please start demo manually. |
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Starting demo at: http://tutorials.ubuntu.com-pr-755.run.demo.haus/ |
Just use dirname everywhere
| In your ssh session to your device: | ||
| ```bash | ||
| snap refresh core --edge | ||
| ``` |
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That causes a reboot, right? Maybe worth a note?
| On your ssh session to your device: | ||
| ```bash | ||
| snap install --dangerous iot-example-graphical-xwayland-snap_0.1_arm64.snap | ||
| snap connect iot-example-graphical-xwayland-snap:wayland-socket-dir mir-kiosk:wayland-socket-dir |
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Does the x11 interface autoconnect here? Also, can you please explain a bit what this does?
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So it isn't auto-connecting. The plug does apply to itself, i.e. since we declare that we satisfy the x11 plug, then the correct apparmor permissions for an X11 server (here Xwayland) are being automatically applied, i.e. bind to a socket. Here's the profile location:
/var/lib/snapd/apparmor/profiles/snap.iot-example-graphical-xwayland-snap.glxgears-kiosk
and contents on install: https://pastebin.ubuntu.com/p/kTgGBxm4kM/
What this connection should be needed for is to allow an x11 client connect to the X socket. These lines are added to to the apparmor profile: https://pastebin.ubuntu.com/p/5cRyhxw73y/
I don't understand why the application works without this. glxgears shouldn't be able to connect to the X11 socket without this. (glxgears not needing fonts or the other bits really)
| content: wayland-socket-dir | ||
| interface: content | ||
| target: $SNAP_DATA/wayland | ||
| default-provider: mir-kiosk |
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I just tested this file as-is, and installing it I got
2018-06-06T13:15:12Z INFO snap "iot-example-graphical-xwayland-snap" has bad plugs or slots: x11-plug (unknown interface "x11-plug")
Seems snapcraft doesn't deal well with having two "plugs" sections. If I combined them into one, that warning was removed.
| On your ssh session to your device: | ||
| ```bash | ||
| snap install --dangerous iot-example-graphical-xwayland-snap_0.1_arm64.snap | ||
| snap connect iot-example-graphical-xwayland-snap:wayland-socket-dir mir-kiosk:wayland-socket-dir |
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So it isn't auto-connecting. The plug does apply to itself, i.e. since we declare that we satisfy the x11 plug, then the correct apparmor permissions for an X11 server (here Xwayland) are being automatically applied, i.e. bind to a socket. Here's the profile location:
/var/lib/snapd/apparmor/profiles/snap.iot-example-graphical-xwayland-snap.glxgears-kiosk
and contents on install: https://pastebin.ubuntu.com/p/kTgGBxm4kM/
What this connection should be needed for is to allow an x11 client connect to the X socket. These lines are added to to the apparmor profile: https://pastebin.ubuntu.com/p/5cRyhxw73y/
I don't understand why the application works without this. glxgears shouldn't be able to connect to the X11 socket without this. (glxgears not needing fonts or the other bits really)
| * Ubuntu Core is available on a range of devices. | ||
| This guide shows you how to set up an existing device: [https://developer.ubuntu.com/core/get-started/installation-medias](https://developer.ubuntu.com/core/get-started/installation-medias). If there's no supported image that fits your needs you can [create your own core image](https://tutorials.ubuntu.com/tutorial/create-your-own-core-image). | ||
| * Using a VM | ||
| You don't *have* to have a physical "Target Device", you can follow the tutorial with Ubuntu Core on a VM: |
| * Using Ubuntu Classic | ||
| You don't *have* to use Ubuntu Core, you can use also a "Target Device" with Ubuntu Classic. You just need to install an SSH server on the device. | ||
| ```bash | ||
| sudo apt install openssh-server |
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ssh is a handy metapackage for this
| * Ubuntu Core is available on a range of devices. | ||
| This guide shows you how to set up an existing device: [https://developer.ubuntu.com/core/get-started/installation-medias](https://developer.ubuntu.com/core/get-started/installation-medias). If there's no supported image that fits your needs you can [create your own core image](https://tutorials.ubuntu.com/tutorial/create-your-own-core-image). | ||
| * Using a VM | ||
| You don't *have* to have a physical "Target Device", you can follow the tutorial with Ubuntu Core on a VM: |
| * Using Ubuntu Classic | ||
| You don't *have* to use Ubuntu Core, you can use also a "Target Device" with Ubuntu Classic. You just need to install an SSH server on the device. | ||
| ```bash | ||
| sudo apt install openssh-server |
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ssh is a handy metapackage for this.
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Starting demo at: http://tutorials.ubuntu.com-pr-755.run.demo.haus/ |
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Great tutorial I really enjoyed reading it, thanks! I'm approving this as I can't see any blocking issues, but I've left plenty of paper cut comments inline you can tackle if you have the time. As some of the text is duplicated, I've only made the comments in the first tutorial. My only general comment is that images would make the tutorial even better.
| * Industrial machine User Interface | ||
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| positive | ||
| : The combination of Snap, the "mir-kiosk" Wayland server and Ubuntu Core ensures reliability and security of any graphical embedded device application. |
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| negative | ||
| : This tutorial assumes you are familiar with the material in [Graphical Snaps for Ubuntu Core](tutorial/graphical-snaps). In particular, techniques for debugging problems in your snap are not covered. | ||
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from a layout perspective, I'm not sure a negative admonition immediately following a positive one is a good look - maybe make the negative an ordinary sentence beneath the above small list?
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| * An Ubuntu desktop running any current release of Ubuntu | ||
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| * Your Target Device |
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A 'Target Device' from one of the following:
| * An Ubuntu desktop running any current release of Ubuntu | ||
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| * Your Target Device | ||
| * Ubuntu Core is available on a range of devices. |
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Ubuntu Core is available on a range of devices. A device running Ubuntu Core.
^ this would also be good with a link to https://www.ubuntu.com/core
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| * Your Target Device | ||
| * Ubuntu Core is available on a range of devices. | ||
| This guide shows you how to set up an existing device: [https://developer.ubuntu.com/core/get-started/installation-medias](https://developer.ubuntu.com/core/get-started/installation-medias). If there's no supported image that fits your needs you can [create your own core image](https://tutorials.ubuntu.com/tutorial/create-your-own-core-image). |
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how about supported device rather than existing device, which may confuse the reader.
| positive | ||
| : **On a Desktop Environment that supports Wayland** you may find that glmark connects to that and not Mir. | ||
| This is easy to work around: tell Mir and the snap how to connect to each other: | ||
| ``` |
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Would be nice, but it leads to a stray "bash" in the preformatted block
| $SNAP/usr/bin/glmark2-wayland | ||
| ``` | ||
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| and point the “command:” in the snapcraft.yaml file to it (don’t forget to install it in the snap!!) |
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I don't follow
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eg. ...and point the "command:", to avoid starting with a lower case a.
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| Because snapping applications can reveal lots of hard-coded paths and assumptions that applications make, which snap confinement will break. It is good to understand the steps needed to debug and solve these problems. | ||
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| There can be many, many environment variables and support files that need to be set up inside snaps, for applications to run correctly. Much of this work has already been done and automated in the *snapcraft-desktop-helpers* project, we will be using this in a follow-up tutorial. |
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project , which we will be using this in a follow-up tutorial.
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| ### Device Setup | ||
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| Open another terminal and ssh login to your device and logged in install the “mir-kiosk” snap. |
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to your device and from this login install the...
| ## Snapping to use mir-kiosk | ||
| duration: 3:00 | ||
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| Changing this snapcraft.yaml to work with mir-kiosk requires one main alteration: Wayland is provided by another snap: mir-kiosk, so we need to get the Wayland socket from it somehow. |
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Replace the first colon with a full stop/period - two colons in a sentence seems a little too much.
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| --- | |||
| id: graphical-snaps | |||
| summary: A guide to creating graphical snaps for Ubuntu IoT devices | |||
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Suggestion: "A guide to creating graphical snaps for Ubuntu IoT devices. Learn how to build a digital signage app for kiosks, advertising screens and other embedded displays."
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| id: graphical-snaps-xwayland | |||
| summary: A guide to creating graphical snaps for Ubuntu IoT devices | |||
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Suggestion: "A guide to creating graphical snaps for Ubuntu IoT devices on top of an XWayland stack. Learn how to build a digital signage app for kiosks, advertising screens and other embedded displays."
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Starting demo at: http://tutorials.ubuntu.com-pr-755.run.demo.haus/ |
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Let us know when you are happy to publish these and I will merge (you will need to change the status in the metadata to 'published' as well |
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@evilnick I'm happy. Pushing the metadata change... |
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Aand they're live! https://tutorials.ubuntu.com/ |
Guide to creating graphical snaps for Ubuntu Core