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Description
Don’t miss out! Join us at our upcoming hybrid event: KubeCon + CloudNativeCon North America 2022 from October 24-28 in Detroit (and online!). Learn more at https://kubecon.io. The conference features presentations from developers and end users of Kubernetes, Prometheus, Envoy, and all of the other CNCF-hosted projects.
The Soul of a New Command: Adding ‘Events’ to kubectl - Bryan Boreham, Grafana Labs
Introduced as an alpha feature in the Kubernetes 1.23 release, the ‘kubectl alpha events’ command resolves some issues that could not be fixed within the generic ‘kubectl get’ command. Join us to re-live and explore: * How the need for ‘kubectl events’ came about. * How Bryan got involved and how you can, too. * The lifecycle of a Kubernetes enhancement.. * How a kubectl command is structured. * Helper libraries to fetch and print Kubernetes objects, and how you can use them in your own code. * Possible future directions for `kubectl [alpha] events`.
A
A
A
So
I
I
work
at
grafana
labs
for
the
first
year
and
that's
that's
not
particularly
relevant
to
the
talk,
but
they
do
pay
me
more
importantly,
you
should
follow
me
on
twitter,
so
I
am
going
to
talk
about
adding
a
command
to
cube
cuddle.
The
command
is
called
cube,
cuddle
events
or
right
now
cube
cattle
alpha
events.
A
So
we'll
start
with.
How
did
I
get
here?
I
I
basically
have
no
idea
or
I
had
no
idea
how
to
add
a
command
to
cubekiddle.
Nor
did
I
ever
think
I
would,
but
I
I
was
working
on
this
thing
k-span,
who
who's
seen
that
a
couple
of
people,
so
it's
pretty
cool.
I
won't
talk
about
it,
but
go
go.
Look
it
up
it
it.
It
gives
you
a
graphical
view
of
events
out
of
your
kubernetes
system.
A
So
let's
just
clarify
what
it.
What
do
I
mean?
What
am
I
talking
about
with
events?
Can
I
do
lasers
yeah?
Not
really.
I
need
a
like
a
more
powerful
laser,
so
events
are
little
little
messages
emitted
by
different
parts
of
your
kubernetes
system,
maybe
from
your
own
code
or
maybe
from
part
of
the
system.
Like
cubelet
or
the
scheduler
or
really
any
part
of
the
system,
and
they
they
go
into
the
api
server
and
let's
take
a
look
this.
This
is
the
sort
of
typical
user
experience
of
events.
A
A
It
has
an
object
here
that
it
relates
to
and
a
sort
of
human
readable
message.
So,
okay,
so
far,
okay,
we've
seen
this
right.
Okay,
so
I
just
want
to
adjust
this
slightly.
There
we
go.
So
this
is
what
an
event
looks
like
if
you
were
to
print
one
out
in
yaml
and
it's
kind
of
kind
of
the
same
stuff
right
we
got
the.
A
We
got
the
message:
we
got
the
reason
we
got
a
few
more
things
like:
where
did
it
come
from
and
the
events
are
kubernetes
objects,
so,
in
the
sense
that
they
are
the
same
thing
to
the
api
server
as
a
pod
or
a
deployment
or
pv,
or
you
know
any
any
of
the
other
objects
within
the
kubernetes
system,
so
they
have
metadata.
They
have
a
name,
they
have
a
namespace,
a
kind
and
a
version.
A
So
if
I
just
go
back
to,
I
don't
know,
I
don't
know
if
anyone
noticed
this,
but
they
they
don't
print
out
in
like
latest.
First
would
be
the
obvious
way
to
do
this
right
and
they
they
don't
they.
They
don't
come
out
in
the
right
order.
In
fact,
they
come
out
in
order
by
name
which
is
like
who
even
who
even
knows
the
name
of
an
event.
A
A
A
A
A
If
you,
if
you
wanna
kind
of
look
in
the
details
and
then
this
new
one
was
created-
and
we
didn't
want
such
a
boring
name
as
v1,
so
we
called
it
events.kates.io
v1-
I
guess-
and
so
this
was
done
so
long
ago-
that
the
the
cap
for
it
is,
is
kind
of
mostly
about
the
cleanup
like
yeah.
We
we're
sort
of
halfway
through
this.
We
better
finish.
A
Almost
everything
if
emits
v1.event
the
scheduler
is
one
component
that
definitely
event
emits
the
other
one,
but
it
will.
It
will
not
do
that
in
its
there's,
a
race
condition
on
startup.
So
I
was
kind
of
trying
to
do
a
demo
for
this
and,
if
you
use
kind,
it
doesn't
exhibit
the
problem
unless
you
restart
the
scheduler.
So
so
I'm
not
going
to
demo
that
yeah,
you
can
read
the
code.
Take
my
word
for
it.
Let's
just
dive
into
the
the
code
a
little
bit
this.
A
This
is
the
code
where
the
events
are
created,
which
I
thought
made
it
easier
to
to
see.
What's
going
on
so
so
the
first
kind
has
involved
object.
It
has
a
first
time
stamp
and
a
last
time
stamp.
So
if
events
are
coalesced,
if,
if
you
have
the
same
bit
of
software
emitting
the
same
event
over
and
over
again,
they
they
can
get
coalesced.
So
so
the
server
only
stores
one
of
them.
So
we
have
a.
We
have
a
first
time
stamp,
a
last
time
stamp
and
an
account
and
then
quick
change.
A
So
in
the
new
one
we
have
an
event
time
and
if
there's
more
than
one
we
have
a.
We
have
a
series
data
structure
which,
which
is
expresses
this
concept,
that
it
happened
several
times
in
a
series
they
renamed
the
involved
object
to.
Regarding
other
things,
like
the
reason
is
still
called
reason,
the
message
is
now
called
note.
A
Now
kubernetes
is
very
big
on
backwards
compatibility,
so
the
good
news,
if
you
like,
is,
is
that
there
is
magic
inside
the
api
server
that
converts
one
each
of
these
to
the
other
one
and
either
way
you
can
ask
for
either
of
these
and
you'll
get
them,
and
even
better
all
of
the
fields
from
the
new
one
are
also
in
the
old
one.
They
were
added
so
so,
like
all
of
the
fields,
all
of
the
choices
are
there.
A
You
can
ask
for
event
time
on
on
the
old
kind
of
event
it
it
is
null,
but
you
it's
there,
you
can
ask
for
it,
and
in
fact
that
is.
That
is
why
they
don't
sort
in
the
right
order,
because,
because
anything
emitting,
the
new
kind
of
event
has
has
a
null
in
in
the
last
timestamp
and
this
used
to
crash
cubekittle.
A
A
Okay,
so
how
do
we
fix
this?
So
kubernetes
is
is
obviously
very,
very
big
project
and
you
can't
just
you
can't
just
go
around
changing
stuff.
You
can
fix
stuff,
you
can
fix
bugs
without
you
know,
asking
someone's
permission
but
fundamentally
changing
the
behavior
of
something
needs.
The
kubernetes
enhancement
process.
A
A
A
A
A
A
I
just
sorry
just
I
see
some
people
standing
at
the
door.
There
are
some
seats
right
at
the
front.
I
won't.
I
won't
like
insult
you
or
anything.
If
you
want
to
sit
near
the
front
and
and
then
you
can
do,
you
can
do
events
for
one
object
and
you
can
watch
for
new
events,
so
the
other
thing
that
people
complain
a
lot
about
cube
cuddle,
get
events.
A
Is
that
if
you,
if
you
watch,
if
you
sort
of
get
them
to
come
out
as
they
happen,
they
all
they
all
come
out
as
they
happen,
and
then
they
all
print
out
again
one
hour,
one
hour
later,
all
the
same
events,
one
hour
later,
who
knows
why
that
is
yeah?
Nobody
right!
It's
because
they
get
deleted
events.
Events
only
live
for
one
hour
and
cube
cuttle
get
minus
watch
prints
out
things
being
created
and
things
being
deleted.
A
A
Okay,
so
suppose
you
want
to
add
a
command
to
cubekittle.
What
are
you
going
to
do?
You
are
going
to
create
a
command
object,
so
so
cubecattle
uses
the
cobra
package
for
cli
applications,
and
so
this
is
the
the
kind
of
what
I
call
step.
Zero,
like
you,
you're
not
going
to
go
anywhere
unless
you
create
this
command
object.
A
So
what
I
did
is
I
I
looked
at
the
existing
commands
like
you
like
cube,
color,
get
for
instance,
or
keep
cuddle
describe
or
whatever
you.
I
guess.
That's
that's
kind
of
the
booster
to
get
going
is
to
find
a
command
that
does
something
a
little
bit
similar
to
what
you
want
to
do
and
copy
paste
that
so
you're
going
to
need
your
command
object.
A
So
there's
a
phase
of
collecting
command
line
arguments
and
they
get
put
in
a
struct,
basically
vanilla,
and
then
the
next
phase
we
kind
of
decode
the
command
line
arguments
and
we
figure
out
what
to
do
with
them
and
the
reason
it's
split
into
those
two
parts
is
is
for
testing
so
that
we
can
kind
of
independently
test
the
act
of
of
receiving
cli
parameters,
separate
from
the
act
of
actually
doing
some
work
on
them
and
and
make
that
easier
to
test.
So
so
I
kind
of
highlighted.
A
So
if
you
have
a
parameter
like
namespace.
Well
that
actually
goes
into
this
guy
gets
kind
of
pre-populated
so
that
when
you
talk
this,
the
rest
rest
is
like
the
api
client
to
the
api
server
and,
and
that
will
be
populated
by
the
machinery
of
cube
cuddle.
To
give
you
a
client
that
is
talking
to
the
right
namespace
and
then
so.
This
one
is
one
that
I
added
on
my
command
and
it's
a
string.
A
So
in
the
in
the
next
phase,
so
same
kind
of
thing.
Well,
it
turns
out,
I
need
to
know
the
namespace,
so
I
pulled
that
out
from
the
the
rest,
client,
getter
and
then
the
so.
This
thing
here
which
object
we're
trying
to
fetch
events
for,
gets
decoded
into
something
more
complicated
and
we'll
talk
about
that
in
a
minute.
A
A
So
probably
the
next
thing
we're
going
to
do
is
is
make
a
api
server
request
and
there
is
a
really
cool
builder
library
to
to
do
all
kinds
of
things
with
api
server
requests.
So
this
one
is
from
cube
cuddle
describe
because
this
is
not
actually
how
cubicle
events
works,
but
I
thought
you
know
this
is
this
is
the
kind
of
the
powerful
library
that
will
work
for
many
many
cases.
So
it's
it's
this
kind
of
pattern
where
each
piece
kind
of
leads
on
from
the
next.
A
It's
called
like
a
fluent
api
that
that's
the
word
that
some
people
use
for
this
kind
of
thing,
so
we
have
a
builder
and
we're
going
to
fetch
unstructured
data,
so
not
go
objects,
just
just
name
value
stuff
and
we're
in
a
namespace.
Maybe
all
namespaces
we're
we're
selecting
on
some
labels
we're
going
to
flatten
them.
So
if
we
get
a
list
of
things
we
don't
want
the
list,
we
want
all
the
objects.
A
So
this
is
very,
very
comprehensive,
very
powerful
and
it
also
covers
things
like
like
chunking.
So
when
you,
when
you
talk
to
the
api
server
and
say,
give
me
all
the
events,
there
might
be
a
million
of
them
and
we
we
do
not
want
to
serialize
a
million
events
into
one
buffer
and
send
that
over
the
network.
So
in
fact
we
fetch
them
like
500
at
a
time
chunking
or
paging,
and
all
of
that
is
is
covered
by
the
machinery
inside
cubicle.
A
A
A
A
A
It's
not
getting
in
everyone's
way,
yeah
so
like
so
here.
Here's
where
we
say
pod
and
in
fact
it
it.
It
accepts
the
singular.
Even
though
the
thing
that's
in
its
table
is
the
is
the
plural
there's
an
abbreviation,
so
you
can
save
one
more
character
if
you
like,
you
can
type
pull,
which
is
a
bit
more
useful
for
something
like
config
map
you
can
type
cm.
A
A
A
A
So
we
have
the
kind
and
the
name
which
is
like
pod,
slash
name
and
then
there's
this
other
cool
part
of
the
machinery
where
we
we
get
to
just
say
I'm
going
to
and
these
two
things
together.
So
this
equals
this
and
this
equals
this.
So
I
can
build
up
my
query
on
the
fields
of
the
event
object
and
that's
what
I'm
going
to
send
to
the
events.
Api
server
yeah,
so
so
in
order
to
get
the
kind.
A
A
I
fill
in
what
I've
got,
so
this
is
a
struct
that
can
take
a
group
aversion
and
a
resource,
but
I
I
only
need
to
fill
in
the
bit.
I've
got,
which
is
like
the
word
pod
in
lower
case,
so
I
fill
in
the
bit.
I've
got
and
I
ask
it
to
map
it,
so
this
can
be
pod
or
pull
or
you
know
configmap
or
cm
or
whatever
you've
got.
You
fill
that
in
here
you
ask
it
to
map
it,
and
then
you
extract
the
kind
from
that.
A
A
A
A
So
if
you
wanna,
if
you
wanna
kind
of
watch
all
the
events
on
one
deployment
or
one
pod
or
or
something
like
that
and
that
changes
at
all,
then
the
events
stop
well.
You
just
can't
watch
on
describe
I
think
anyway,
so
my
one
is
less
specific.
So
so
I'm
gonna
call
that
one
done
combining
columns.
Well
this
this
was
about
the
some
of
them
have
last
timestamp
and
some
of
them
have
event
time.
A
A
A
It
is
in
alpha,
so
definitely
looking
for
feedback
and
looking
for
thoughts,
you
know
bugs
in
it
or
ways
to
improve
it
or
or
whatever,
so
one
one
idea
would
would
be
to
add
a
thing
to
limit
how
far
back
like
you
know,
maybe
you
just
want
to
see
events
in
the
last
five
minutes
or
or
something
like
that.
So
that
would
be
that
that's,
I
think,
kind
of
related
to
the
one
about
the
time.
A
It
could
be
going
wrong
on
a
pod
and
they're
all
kind
of
related,
but
you
have
to
be
a
sort
of
kubernetes
super
being
to
know
where
to
look
for
this
information,
so
so
maybe
the
maybe
the
thing
could
just
know
that
itself
and
and
do
that
yeah
and
lastly,
you
know
what
what
do
you
want?
What
I
I
put
it
out
there
for
the
world,
please
file
issues,
or,
I
don't
know,
send
me-
tweets,
send
tweet
anyway.
That's
the
end
of
my
talk
I'll,
take
questions
in
a
minute.
B
C
A
Yeah
well
so
there
there's
a
cap
for
new
events
to
replace
old
ones.
The
the
new
events
are
more
flexible.
So
yes,
that's
that's
yeah.
Maybe
I
should
have
researched
that.
I
guess
that's
one
for
sig,
api
machinery
or
or
something
like
that
I
mean
certainly
certainly
that's.
The
stated
intention
is
that
the
case
dot
io
events
should
replace
v1.event
but
in
a
backwards
compatible
way
right.
So
so
you
can
always
query
for
the
for
the
previous
one.
D
A
A
A
A
No,
let
me
think
about
that.
So
some
of
these
things
work
on
a
prefix
and
I
actually
don't
remember
whether
that
works
for
cube
cattle
get
events,
but
I
I
mean
I
showed
you
the
code.
It
says
equal
so
right
now
it
doesn't
have
a
regex
matching
but
file
file,
an
enhancement
request
on
github,
slash,
kubernetes,
cubekittle.
F
A
A
G
A
Yeah
yeah,
so
I
think
I
agree
with
the
spirit
of
what
you're
saying
that
the
I
mean
I
I
tried
to
demonstrate,
there's
some
really
powerful
libraries
in
there,
but
still
not
exactly
the
thing
I
wanted
and
in
some
cases,
like
the
thing
that
that
specific
thing
that
you
mentioned
about
how
to
decode
the
name
that
is
in
cubecan,
will
describe,
but
it's
not
exported,
and
after
a
little
bit
of
to
and
fro
with
the
maintainers,
we
agreed
that
I
would
re-implement
it.
So
there's
a
kind
of
a
go
proverb.