From Newsgroup: comp.sys.raspberry-pi

I have a Raspberry Pi 5 running the latest version of Bookworm and using
Labwc as the GUI.

I have Grafana displaying the Internet Speed installed as here.

https://dev.to/benji377/grafana-speed-monitor-setting-up-an-internet-monitor-with-raspberry-pi-50jk

I boot straight into Grafana using Kiosk mode by editing the /etc/xdg/labwc/autostart file and adding this line to the end


chromium = /usr/bin/chromium-browser --start-fullscreen
--start-maximized --kiosk --hide-scrollbars --noerrdialogs --disable-default-apps --disable-single-click-autofill --disable-translate-new-ux --disable-translate --disable-cache --disk-cache-dir=/dev/null --disk-cache-size=1
--reduce-security-for-testing --app=http:///127.0.0.1:3030&kiosk

This works perfectly - however when I first boot Grafana takes a little
while to start up and for the first minute or so I get a "Site Not Found
Page" which eventually clears and Grafana is shown.

No biggy but looks a little messy!

Is there anyway to put a pause in the autostart sequence to allow
Grafana to load??

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From Newsgroup: comp.sys.raspberry-pi

DrStevenStrange <kubmw2ce@duck.com> wrote:

I have a Raspberry Pi 5 running the latest version of Bookworm and using Labwc as the GUI.

I have Grafana displaying the Internet Speed installed as here.

https://dev.to/benji377/grafana-speed-monitor-setting-up-an-internet-monitor-with-raspberry-pi-50jk

I boot straight into Grafana using Kiosk mode by editing the /etc/xdg/labwc/autostart file and adding this line to the end

chromium = /usr/bin/chromium-browser --start-fullscreen
--start-maximized --kiosk --hide-scrollbars --noerrdialogs --disable-default-apps --disable-single-click-autofill --disable-translate-new-ux --disable-translate --disable-cache --disk-cache-dir=/dev/null --disk-cache-size=1
--reduce-security-for-testing --app=http:///127.0.0.1:3030&kiosk

This works perfectly - however when I first boot Grafana takes a little while to start up and for the first minute or so I get a "Site Not Found Page" which eventually clears and Grafana is shown.

No biggy but looks a little messy!

Is there anyway to put a pause in the autostart sequence to allow
Grafana to load??

You could make a script something like:

#!/bin/sh

sleep 120
/usr/bin/chromium-browser --start-fullscreen \
--start-maximized --kiosk --hide-scrollbars --noerrdialogs \
--disable-default-apps --disable-single-click-autofill \
--disable-translate-new-ux --disable-translate --disable-cache \
--disk-cache-dir=/dev/null --disk-cache-size=1 \
--reduce-security-for-testing --app=http:///127.0.0.1:3030&kiosk


and then put the name of that script to be your autostart. This will delay starting Chromium for 120 seconds when xdg autostarts it.

Theo
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From Newsgroup: comp.sys.raspberry-pi

Theo wrote:

#!/bin/sh

sleep 120
/usr/bin/chromium-browser --start-fullscreen \
--start-maximized --kiosk --hide-scrollbars --noerrdialogs \
--disable-default-apps --disable-single-click-autofill \
--disable-translate-new-ux --disable-translate --disable-cache \
--disk-cache-dir=/dev/null --disk-cache-size=1 \
--reduce-security-for-testing --app=http:///127.0.0.1:3030&kiosk

Brilliant.

Works perfectly

Many thanks
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From Newsgroup: comp.sys.raspberry-pi

On Sun, 1 Jun 2025 07:08:34 +0100, DrStevenStrange wrote:

chromium = /usr/bin/chromium-browser --start-fullscreen
--start-maximized --kiosk --hide-scrollbars --noerrdialogs --disable-default-apps --disable-single-click-autofill --disable-translate-new-ux --disable-translate --disable-cache --disk-cache-dir=/dev/null --disk-cache-size=1
--reduce-security-for-testing --app=http:///127.0.0.1:3030&kiosk

This works perfectly - however when I first boot Grafana takes a
little while to start up and for the first minute or so I get a
"Site Not Found Page" which eventually clears and Grafana is shown.

Instead of waiting for some fixed interval, you could add a prior command using wget or something to repeatedly try accessing that URL, say at 5
second intervals or whatever, until it becomes accessible, before allowing
the startup to proceed.
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From Newsgroup: comp.sys.raspberry-pi

In article <101itmk$2mr8t$1@dont-email.me>,
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:

Instead of waiting for some fixed interval, you could add a prior command >using wget or something to repeatedly try accessing that URL, say at 5 >second intervals or whatever, until it becomes accessible, before allowing >the startup to proceed.

For inspiration, I made a script to 'etherwake' a device and wait for it
to get ready using wget in combination with the 'timeout' command. I run 'timeout 1 wget <url>' which returns an error if wget does not respond
in 1 second, or wget returns an error itself. I use this in a while
loop that repeats this until the wget succeeds:

etherwake -D -i ${IFACE} ${MACADDR}

while ! timeout 1 curl --noproxy \* "${URL}" &> /dev/null
do
echo -n .
sleep 1
done

The OP could replace the 'sleep 120' in the other script with this loop.
--
[J|O|R] <- .signature.gz
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From Newsgroup: comp.sys.raspberry-pi

On 03/06/2025 at 14:00, Oscar wrote:

In article <101itmk$2mr8t$1@dont-email.me>,
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:

Instead of waiting for some fixed interval, you could add a prior command
using wget or something to repeatedly try accessing that URL, say at 5
second intervals or whatever, until it becomes accessible, before allowing >> the startup to proceed.

For inspiration, I made a script to 'etherwake' a device and wait for it
to get ready using wget in combination with the 'timeout' command. I run 'timeout 1 wget <url>' which returns an error if wget does not respond
in 1 second, or wget returns an error itself. I use this in a while
loop that repeats this until the wget succeeds:

etherwake -D -i ${IFACE} ${MACADDR}

while ! timeout 1 curl --noproxy \* "${URL}" &> /dev/null
do
echo -n .
sleep 1
done

The OP could replace the 'sleep 120' in the other script with this loop.

Why waste a curl call when ping 8.8.8.8 would work with less overhead?
--
Chris Elvidge, England
I WILL NOT MESS WITH THE OPENING CREDITS

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From Newsgroup: comp.sys.raspberry-pi

Chris Elvidge <chris@internal.net> wrote:

On 03/06/2025 at 14:00, Oscar wrote:

In article <101itmk$2mr8t$1@dont-email.me>,
Lawrence D'Oliveiro <ldo@nz.invalid> wrote:

Instead of waiting for some fixed interval, you could add a prior command >> using wget or something to repeatedly try accessing that URL, say at 5
second intervals or whatever, until it becomes accessible, before allowing >> the startup to proceed.

For inspiration, I made a script to 'etherwake' a device and wait for it
to get ready using wget in combination with the 'timeout' command. I run 'timeout 1 wget <url>' which returns an error if wget does not respond
in 1 second, or wget returns an error itself. I use this in a while
loop that repeats this until the wget succeeds:

etherwake -D -i ${IFACE} ${MACADDR}

while ! timeout 1 curl --noproxy \* "${URL}" &> /dev/null
do
echo -n .
sleep 1
done

The OP could replace the 'sleep 120' in the other script with this loop.

I was going to suggest something similar like that too. It is worth
checking what the webserver is giving you - some services give a generic 'please wait while I start up' web page which may not be what you want.
Maybe you need to ask for a specific page and count a redirect (to the
'please wait') page as a failure.

Why waste a curl call when ping 8.8.8.8 would work with less overhead?

The purpose is to test a specific service *on this machine* has started up,
not generic internet connectivity.

Theo
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From Newsgroup: comp.sys.raspberry-pi

On 03/06/2025 15:17, Chris Elvidge wrote:

On 03/06/2025 at 14:00, Oscar wrote:

In article <101itmk$2mr8t$1@dont-email.me>,
Lawrence D'Oliveiro  <ldo@nz.invalid> wrote:

Instead of waiting for some fixed interval, you could add a prior
command
using wget or something to repeatedly try accessing that URL, say at 5
second intervals or whatever, until it becomes accessible, before
allowing
the startup to proceed.

For inspiration, I made a script to 'etherwake' a device and wait for it
to get ready using wget in combination with the 'timeout' command. I run
'timeout 1 wget <url>' which returns an error if wget does not respond
in 1 second, or wget returns an error itself. I use this in a while
loop that repeats this until the wget succeeds:

     etherwake -D -i ${IFACE} ${MACADDR}

     while ! timeout 1 curl --noproxy \* "${URL}" &> /dev/null
     do
         echo -n .
         sleep 1
     done

The OP could replace the 'sleep 120' in the other script with this loop.

Why waste a curl call when ping 8.8.8.8 would work with less overhead?

+1. Assuming that pings to the Wide World are not blocked by the network
--
"Strange as it seems, no amount of learning can cure stupidity, and
higher education positively fortifies it."

- Stephen Vizinczey


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From Newsgroup: comp.sys.raspberry-pi

In article <101n06i$264r$1@dont-email.me>,
Chris Elvidge <chris@internal.net> wrote:

while ! timeout 1 curl --noproxy \* "${URL}" &> /dev/null
do
echo -n .
sleep 1
done

The OP could replace the 'sleep 120' in the other script with this loop.

Why waste a curl call when ping 8.8.8.8 would work with less overhead?

Will 'ping 8.8.8.8' return quickly (within 2 seconds) after my device
has woken up? No. My device does not respond to 8.8.8.8. You are just
testing internet connectivity, not the wakeup of my device.

And why waste a ping call (which is setuid) if a curl call will suffice
AND tells if the port is responding to http(s) requests?

In other words: why waste a post when you don't understand the problem?
--
[J|O|R] <- .signature.gz
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From Newsgroup: comp.sys.raspberry-pi

In article <lKm*Ch8dA@news.chiark.greenend.org.uk>,
Theo <theom+news@chiark.greenend.org.uk> wrote:

I was going to suggest something similar like that too. It is worth
checking what the webserver is giving you - some services give a generic >'please wait while I start up' web page which may not be what you want. >Maybe you need to ask for a specific page and count a redirect (to the >'please wait') page as a failure.

In my use case this was enough. You can also direct curl output to grep
and use that as an indicator of your device's desired state.

Why waste a curl call when ping 8.8.8.8 would work with less overhead?

The purpose is to test a specific service *on this machine* has started up, >not generic internet connectivity.

Yeah. And curl is not *that* expensive to run. Maybe even less expensive
than ping, as it does not have the setuid overhead. But who's counting
clock cycles anyway?
--
[J|O|R] <- .signature.gz
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From Newsgroup: comp.sys.raspberry-pi

In article <101n27u$20jc$5@dont-email.me>,
The Natural Philosopher <tnp@invalid.invalid> wrote:

+1. Assuming that pings to the Wide World are not blocked by the network

-1 for assuming that internet connectivity is the only requirement.
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[J|O|R] <- .signature.gz
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From Newsgroup: comp.sys.raspberry-pi

In article <101niml$7k6m$2@dont-email.me>,
Oscar <jornws200602@xs4all.nl> wrote:

Yeah. And curl is not *that* expensive to run. Maybe even less expensive
than ping, as it does not have the setuid overhead. But who's counting
clock cycles anyway?

Following up on myself: Okay, ping loads a bit quicker as it's
executable is smaller and it loads less libraries, but it still
is a setuid binary.

I must admit I still don't understand why you thing the overhead of
calling curl is a waste. Both are external programs and we're in a wait
loop anyway. Why hurry in between to sleep calls?

In this case curl beats ping, as OP's question was related to a slow
staring Grafana server. Ping can't tell if Grafana is running. With curl
you can see if a string is in the output.

Say for examplje you're waiting for a specific dasboard to load, with
the title "Hootenmany". You could run this slightly modified version:


while ! timeout 1 curl -s ${URL} | grep -qs Hootenanny
do
echo -n .
sleep 1
done

This will loop until curl returns something with the string 'Hootenanny'
within 1 second and fail if there's no network, no dns, no route to the
Grafana server or while Grafana server is still starting up.

And *that's* what the OP asked.
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From Newsgroup: comp.sys.raspberry-pi

On 03/06/2025 20:34, Oscar wrote:

In article <101n27u$20jc$5@dont-email.me>,
The Natural Philosopher <tnp@invalid.invalid> wrote:

+1. Assuming that pings to the Wide World are not blocked by the network

-1 for assuming that internet connectivity is the only requirement.

Accepted.
--
It is the folly of too many to mistake the echo of a London coffee-house
for the voice of the kingdom.

Jonathan Swift


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