First, let me say that all of May has been a very difficult
month weather-wise for those of us in Oklahoma, then later in May, for folks in
Texas. Thankfully, all the tornadoes and flooding did not affect us personally,
but we have friends and neighbors who were impacted and some of the stories are
just tragic. So, I ask that if you are able to send a relief gift to the Red
Cross designated for these disasters, please do so. It would really help those
in need.
Here in Oklahoma we have had two years of extreme drought.
One of the major lakes was over 31 feet below normal levels. Now, it has risen
to 99% capacity. We have some lakes that are 33 feet above normal. Just in the
month of May we have had 27.5 inches of rain, which shatters the record for the
wettest month in history
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(May 2013 with 14.52 inches and the all time
monthly record was 14.66 in June of 1989). Texas has also seen
similar records broken. In short, we’ve had all the rain we need, thank you.
California, we would be happy for you to get some of this for your drought.
The image above is of the main street of my hometown, Chickasha, OK.
Then, there are the tornadoes that make everything even more
exciting. One night this month, we had to take shelter twice but no damage,
thankfully. Then yesterday morning I was awakened at 5:30 a.m. to the sounds of
tornado sirens. That is freaky because you have to act fast to see what is
really happening. In this case, the tornado was 40 miles away, heading the
opposite direction. I question the decision to sound the alarm in that
situation.
Anyway…with that context…
About a week ago, I started noticing ants everywhere in and
around our house. I mean parades of them everywhere. Ironically, I even found
one crawling on my MacBook Pro!
Then, came the spiders, a plethora of other bugs, snakes and
even fish in some peoples’ years. A friend reported seeing a solid white
opossum near his house, which is very unusual.
And you perhaps heard that in one tornado event nearby on
May 6, a wild animal preserve was hit and it was reported for a while that
lions, bears, tigers, etc. were loose. Turns out that was a false report, too.
But it did make for some juicy Facebook pictures for “Tigernado”
movies.
Other weird things have happened as well, such as storm
shelters and entire swimming pools popping out of the ground due to the high
water table (and poor installation in some cases)!
But back to the ants and bugs and why they are everywhere.
Turns out that we have had so much rain, their nests and colonies were
destroyed and they are now looking for other habitats. The same has occurred
with spiders, snakes, mice and rats.
In fact, my wife and I are finding bugs we have never seen
before. I had to look some of them up on the Internet just to know what kind of
bug I was killing.
That caused me to think about a new testing analogy to
reinforce a really great testing technique. To flush out the bugs in
something, change the environment.
Of course, the difference here in this analogy is that
software bugs are not like actual bugs in many regards. However, there are some
similarities:
·
Both have taxonomies
·
Both can be studied
·
Both can mutate
·
Both can travel
·
Both can destroy the structure of something
·
Both can be identified and removed
·
Both can be prevented
·
Both can be hidden from plain view
The main differences are:
·
Bugs have somewhat predictable behavior – not
all software defects do
·
Bugs can inhabit a place on their own initiative
– software defects are created by people due to errors
(Although I have wondered how squash bugs know how just to
infest squash plants and nothing else…)
In the recent onslaught of ants, it is the flooding that has
caused them to appear in masses. In software, perhaps if you flooded the
application with excessive amounts of data such as long data strings in fields,
you might see some new bugs. Or, you could flood a website with concurrent
transaction load to see new and odd behavior.
Perhaps you could do
the opposite and starve the environment of memory, CPU availability, disk
space, etc. to also cause bugs to manifest as failures.
This is not a new idea by any means. Fault injection has
been used for many years to force environmental conditions that might reveal
failures and defects. Other forms of fault injection directly manipulate code.
Another technique is
to test in a variety of valid operational environments that have different
operating systems, hardware capacities and so forth. This is a great technique
for testing mobile devices and applications. It’s also a great technique for
web-based testing and security testing.
The main principle
here is that if you can get the application to fail in a way that causes it to
change state (such as from “normal state” to “failure state”, then it is
possible to use that failure as a point of vulnerability. Once the defect
has been isolated and fixed, not only has a defect been found and fixed, but
also another security vulnerability has been eliminated.
Remember, as testers we are actually trying to cause
failures that might reveal the presence of defects. Failure is not an option – it is
an objective!
Although, we commonly say that testers are looking for defects
(bugs), the bugs are actually out of our view many times. They are in the code,
the integration, APIs, requirements, and so forth. Yes, sometimes we see the
obvious external bug, like an error message with confusing wording, or no
message at all.
However, in the external functional view of an application
or system, testers mainly see the indicators of defects. These can then be
investigated for a final determination of really what is going on.
As testers, we can dig for the bugs (which can also be productive),
or we can force the bugs to manifest themselves by flushing them out with
environmental changes.
There is one more aspect to this situation. With all the standing water and moisture, the next phase will be mosquitoes and ticks. The tick invasion has already started. Instead of being flushed out my the flooding, these parasites are attracted to it. What attracts the bugs in your software?
There is one more aspect to this situation. With all the standing water and moisture, the next phase will be mosquitoes and ticks. The tick invasion has already started. Instead of being flushed out my the flooding, these parasites are attracted to it. What attracts the bugs in your software?
And let’s be real here. In some software, the bugs are not
at all hard to find!
Me? I’ll continue to both dig and flush to find those
defects. Even better, I’ll go upstream where the bugs often originate (in
requirements, user stories, etc.) and try to find them there!
