Category: Technology

Strange Windows 10 / MS Paint Bug

My arrow keys were moving my mouse pointer. And, unlike all of the search results which said I had turned on some ease-of-use feature …

It seems like there is an odd bug between Windows 10 build 1903 and MS Paint. I had a pbrush window open and had selected some of the image (something I was pasting into a usage document). Somehow the “arrow keys move this selection around in pbrush” translated into the arrow keys moving my mouse pointer around everywhere else. Simply closing pbrush sorted the problem.

It’s not something I can reproduce at will — opening pbrush, pasting in whatever screen shot I’ve got in my clipboard, selecting and grabbing a section of it … and the arrow keys are not moving the mouse pointer. But some combination of this process has, twice today, caused the arrow keys to move the mouse pointer. At least it’s an easy fix 🙂

Git: Using Soft Reset To Clean Up Un-pushed Commits

I missed a file when I was cleaning up debugging lines. I made the change and included it in a second commit, but I’d rather not have two commits for the same purpose. I hadn’t pushed my changes yet, so these commits only exist on my workstation … which means I can reset and bundle the changes into a single commit.

Find commit number that is one before the duplicate debug logging cleanup — this is the point to which you want to reset. In my case, it is the commit start with b443348c

Reset there with “–soft” — this doesn’t change anything on the file system (i.e. I don’t have to clean up those debug lines again) but puts the changes back into the staging area.

Now those files are staged again, so I can make a single commit for removing debug logging from my code.

Voila! I can push these changes and not clutter our history with my error.

 

Displaying An Image Tooltip

JQuery developers seem to have put a lot of effort into filtering HTML components out of tooltips … which, as someone who visits a website … is A Good Thing. But what’s a good security consideration can be a massive pain when building a website. I have a form which takes an internal ID number, and I have an image showing people how to find that internal ID number. I want a little question mark after the field name that pops up the image as a tooltip on mouseover events. And clears the image on mouseout.

JavaScript:

// Show finding equipment ID image "tooltip" 
$('#ShowEquipmentIDTip').hover(
	function(){
        	$('#FindingEID').css({ "display": "block" });
    	}
	,function(){
        	$('#FindingEID').css({ "display": "none" });
    	}
);
HTML:
<div class="col-md-2 col-sm-2 col-lg-2 col-xs-2 text-left">
	<span><strong>Equipment ID(s): <a id="ShowEquipmentIDTip" href="#">(?)</a></strong></span>
	<div id="FindingEID" style="position: relative;top: 20;left: 60;width: 100%;height: 100%;z-index:99;display:none"><img src="/groomsGenerateCircuitReport/images/Tip-FindingEquipmentID.png" /></div>
</div>

Moving your mouse over the ShowEquipmentIDTip a element displays the div which contains my image “tooltip” and moving the mouse away sets the display back to none.

Recovering a bricked Netgear router

Netgear provides instructions for using TFTP to write firmware to a basically bricked router (it boots into a recovery mode, indicated by a flashing power light). The instructions are, unfortunately, specific to Windows. To use a Linux computer to recover the router

 

(1) Plug your computer into the router & unplug everything else, as in the instructions. Hard-code an IP address. Then verify that the router shows up in your arp table:

arp -a

If the router does not appear, add it — you’ll need to get the device MAC address from the sticker on the back of the device.

arp -s 192.168.1.1 ??-??-??-??-??-??

(2) If you don’t already have a TFTP client, install one. Once you have a client, follow the instructions to get the router into recovery mode. On the Linux computer, run “tftp 192.168.1.1”

You’ll be in a TFTP console. Type binary and hit enter to set the transfer mode to binary. Then use put /path/to/file.name to upload the firmware file to the device. Wait and proceed with device setup.

 

Shell Script: Path To Script

We occasionally have to re-home our shell scripts, which means updating any static path values used within scripts. It’s quick enough to build a sed script to convert /old/server/path to /new/server/path, but it’s still extra work.

The dirname command works to provide a dynamic path value, provided you use the fully qualified path to run the script … but it fails spectacularly whens someone runs ./scriptFile.sh and you’re trying to use that path in, say, EXTRA_JAVA_OPTS. The “path” is just . — and Java doesn’t have any idea what to do with “-Xbootclasspath/a:./more/path/goes/here.jar”

Voila, realpath gives you the fully qualified file path for /new/server/path/scriptFile.sh, ./scriptFile.sh, or even bash scriptFile.sh … and the dirname of a realpath is the fully qualified path where scriptFile.sh resides:

#!/bin/bash 
DIRNAME=`dirname $(realpath "$0")`
echo ${DIRNAME}

Hopefully next time we’ve got to re-home our batch jobs, it will be a simple scp & sed the old crontab content to use the new paths.

Memory upgrade on Flex 3 1580

The vendor specs for a Lenovo Flex 3 1580 say it supports up to 8GB of RAM. There are some forum threads that say the D3CN35WW BIOS update supports up to 16GB, but the vendor spec hasn’t been updated so it’s chancy. I finally decided to chance it – I’ve got a few Docker VMs that I use for development, a Citrix published app that I need to access, and I like to have a dozen tabs open in Firefox. All of this means that I regularly run out of memory.

I ordered a 16GB module from Amazon, installed it … and

It works!

 

Exchange Mail & Calendar In Teams (duct tape approach, not official MS solution)

The Exchange web client renders in the Teams website tab now – Chrome and Chromium-based Edge. I use the nightly build of FireFox and it says ‘Blocked by X-Frame-Options Policy’

This isn’t a way to get new mail notifications in Teams – you’ve got to click over to the tab. But it does let you send a quick message without leaving Teams.

It’s a little inconvenient, though, to have to navigate over to the right channel to find the website tab. You can also create a custom Teams application to access the Exchange website. That’s a little more complicated, but you basically need a manifest.json with static tabs to the inbox and calendar.

Install and open “App Studio” in Teams. Create a new app. Fill in the details — use the generate button to get an app ID. Since you’re not going to publish the app to the Microsoft app store, the info you use isn’t super important … the privacy and terms of use, specifically, aren’t something anyone is going to read.

And

In the “Capabilities” section, add a personal tab

Add a tab for the mailbox:

If you wish, add a tab for the calendar – I prefer the weekly view, but you can replace “week” with “workweek”, “day”, or “month”.

In the “Test and Distribute”, click “Download”.

You’ll get a zip file that you can side-load (i.e. it’s not an app published across the company). In “Apps”, select “Upload a custom app”

Locate the downloaded ZIP file and open it

Verify that your app looks right – the permissions are base permissions for all apps (we didn’t add anything special)

Click “Add” and you’ll be able to select the new app from the ellipses in Teams.

And you’ll have an app that can access your mailbox

Or a week view of your calendar

 

Modifying Shared PHP Function

We needed to modify a shared function to include additional information … but didn’t want to coordinate changing all of the calls to the function as one change. Simplest way to accomplish that was to set a default value for the new parameter — either to NULL and just not do the new thing when the parameter is NULL or some value that indicates that we’re not yet gathering that data.

<?php

function testFunction($strOldParameter, $strNewParameter=NULL){
     echo "The old parameter is |$strOldParameter|\n";
     if($strNewParameter){
          echo "The new parameter is |$strNewParameter|\n";
     }
}

testFunction("first", "second");
testFunction("justFirst");

?>

Microsoft Teams: Private Channels Arrive

WooHoo! When creating a channel, I have a privacy setting!!

Individuals who do not have access to the channel do not see it in their Teams listing, and posts made to a private channel cannot at-mention the Team or individuals who do not have access. I’m glad Microsoft landed on the side of privacy in their implementation here.

It would be awesome if MS would have added the ability to move channels into other Teams with this rollout so we could consolidate Teams that were set up to restrict access to content. But at least we’ll be able to consolidate general-access and restricted-access content in a single Teams space going forward.

 

Preventing erronious use of the master branch on development servers

One of the web servers at work uses a refspec in the “git pull” command to map the remote development branch to the local remote-tracking master branch. This is fairly confusing (and it looks like the dev server is using the master branch unless you dig into how the pull is performed), but I can see how this prevents someone from accidentally typing something like “git checkout master” and really messing up the development environment. I can also see a dozen ways someone can issue what is a completely reasonable git command 99% of the time and really mess up the development environment.

While it is simple enough to just checkout the development branch, doing so does open us up to the possibility that someone will erroneously  deliver the production code to the development server and halt all testing. While you cannot create shell aliases for multi-word commands (or, more accurately, alias expansion is performed for the first word of a simple command is checked to see if it has an alias … so you’ll never get the multi-word command), you can define a function to intercept git commands and avoid running unwanted commands:

function git() { 
     case $* in 
         "checkout master" ) command echo "This is a dev server, do not checkout the master branch!" ;; 
         "pull origin master" ) command echo "This is a dev server, do not pull the master branch" ;; 
         * ) command git "$@" ;; 
     esac
}

Or define the desired commands and avoid running any others:

function git(){
     if echo "$@" | grep -Eq '^checkout uat$'; then
          command git $@
     elif echo "$@" | grep -Eq '^pull .+ uat$'; then
          command git $@
     else
          echo "The command $@ needs to be whitelisted before it can be run"
     fi
}

Either approach mitigates the risk of someone incorrectly using the master branch on the development server.