Wiser coders than myself have come to the conclusion that a `switch`
statement is almost always superior to a statement that includes any
`else if`.
The exceptions that I have found in our codebase are just these two:
* The `if else` is followed by an additional statement before the next
condition (separated by a `;`).
* The whole thing is within a `for` loop and `break` statements are
used. In this case, using `switch` would require tagging the `for`
loop, which probably tips the balance.
Why are `switch` statements more readable?
For one, fewer curly braces. But more importantly, the conditions all
have the same alignment, so the whole thing follows the natural flow
of going down a list of conditions. With `else if`, in contrast, all
conditions but the first are "hidden" behind `} else if `, harder to
spot and (for no good reason) presented differently from the first
condition.
I'm sure the aforemention wise coders can list even more reasons.
In any case, I like it so much that I have found myself recommending
it in code reviews. I would like to make it a habit in our code base,
without making it a hard requirement that we would test on the CI. But
for that, there has to be a role model, so this commit eliminates all
`if else` occurrences, unless it is autogenerated code or fits one of
the exceptions above.
Signed-off-by: beorn7 <beorn@grafana.com>
While originally the resync period also forced refreshing from Kubernetes API server, this has been removed for some years now because watching the API server got more stable [1]. Today, this just results in all entities being sent to the service discovery again, which is valid from a general Prometheus perspective, but results in unnecessary CPU load and also breaks service discovery metrics. In especially, this makes monitoring "do we actually observe changes from Kubernetes API server" impossible (receiving constant updates from Kubernetes service discovery is a pretty valid assumption, for example nodes get frequent status updates, ...).
Signed-off-by: Jens Erat <jens.erat@mercedes-benz.com>
The Kubernetes service discovery can only add node labels to
targets from the pod role.
This commit extends this functionality to the endpoints and
endpointslices roles.
Signed-off-by: Filip Petkovski <filip.petkovsky@gmail.com>
* refactor: move from io/ioutil to io and os packages
* use fs.DirEntry instead of os.FileInfo after os.ReadDir
Signed-off-by: MOREL Matthieu <matthieu.morel@cnp.fr>
Fail configuration unmarshalling if kubeconfig or api url are set with
"own namespace"
Only read namespace file if needed.
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
When using Kubernetes service discovery on a Prometheus instance that's
not running inside Kubernetes, the creation of the service discovery
fails with a "no such file or directory" error as the special
`/var/run/secrets/kubernetes.io/serviceaccount/namespace` file is not
there. This commit moves the code that reads this file into the
if-branch where no `APIServer.URL` is given (that one basically makes
Prometheus assume it is running inside of a Kubernetes cluster).
Signed-off-by: Georg Gadinger <nilsding@nilsding.org>
When using Kubernetes service discovery on a Prometheus instance that's
not running inside Kubernetes, the creation of the service discovery
fails with a "no such file or directory" error as the special
`/var/run/secrets/kubernetes.io/serviceaccount/namespace` file is not
there. This commit moves the code that reads this file into the
if-branch where no `APIServer.URL` is given (that one basically makes
Prometheus assume it is running inside of a Kubernetes cluster).
Signed-off-by: Georg Gadinger <nilsding@nilsding.org>
This commit adds support for discovering targets from the same
Kubernetes namespace as the Prometheus pod itself. Own-namespace
discovery can be indicated by using "." as the namespace.
Fixes#9782
Signed-off-by: fpetkovski <filip.petkovsky@gmail.com>
We are re-enabling HTTP 2 again. There has been a few bugfixes upstream
in go, and we have also enabled ReadIdleTimeout.
Fix#7588Fix#9068
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
This PR introduces support for follow_redirect, to enable users to
disable following HTTP redirects.
Signed-off-by: Julien Pivotto <roidelapluie@inuits.eu>
Label selector can be
"set-based"(https://kubernetes.io/docs/concepts/overview/working-with-objects/labels/#set-based-requirement)
but such a selector causes Prometheus start failure with the "unexpected
error: parsing YAML file ...: invalid selector: 'foo in (bar,baz)';
can't understand 'baz)'"-like error.
This is caused by the `fields.ParseSelector(string)` function that
simply splits an expression as a CSV-list, so a comma confuses such a
parsing method and lead to the error.
Use `labels.Parse(string)` to use a valid lexer to parse a selector
expression.
Closes#8284.
Signed-off-by: Alexey Shumkin <Alex.Crezoff@gmail.com>
This also fixes a bug in query_log_file, which now is relative to the config file like all other paths.
Signed-off-by: Andy Bursavich <abursavich@gmail.com>
The Kubernetes client records workqueue duration and latency metrics as
seconds so there's no need to convert the values from microseconds to
seconds anymore.
The cache metrics (prometheus_sd_kubernetes_cache_*) are removed because
they aren't used anymore by the client though still exposed by its API.
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
* Update go.mod dependencies before release
Signed-off-by: Julius Volz <julius.volz@gmail.com>
* Add issue for showing query warnings in promtool
Signed-off-by: Julius Volz <julius.volz@gmail.com>
* Revert json-iterator back to 1.1.6
It produced errors when marshaling Point values with special float
values.
Signed-off-by: Julius Volz <julius.volz@gmail.com>
* Fix expected step values in promtool tests after client_golang update
Signed-off-by: Julius Volz <julius.volz@gmail.com>
* Update generated protobuf code after proto dep updates
Signed-off-by: Julius Volz <julius.volz@gmail.com>
i) Uses the more idiomatic Wrap and Wrapf methods for creating nested errors.
ii) Fixes some incorrect usages of fmt.Errorf where the error messages don't have any formatting directives.
iii) Does away with the use of fmt package for errors in favour of pkg/errors
Signed-off-by: tariqibrahim <tariq181290@gmail.com>
* discovery/kubernetes: fix support for password_file
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
* Create and pass custom RoundTripper to Kubernetes client
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
* Use inline HTTPClientConfig
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
* *: use latest release of staticcheck
It also fixes a couple of things in the code flagged by the additional
checks.
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
* Use official release of staticcheck
Also run 'go list' before staticcheck to avoid failures when downloading packages.
Signed-off-by: Simon Pasquier <spasquie@redhat.com>
Currently Prometheus requests show up with a UA of Go-http-client/1.1
which isn't super helpful. Though the X-Prometheus-Remote-* headers
exist they need to be explicitly configured when logging the request in
order to be able to deduce this is a request originating from
Prometheus. By setting the header we remove this ambiguity and make
default server logs just a bit more useful.
This also updates a few other places to consistently capitalize the 'P'
in the user agent, as well as ensure we set a UA to begin with.
Signed-off-by: Daniele Sluijters <daenney@users.noreply.github.com>
* tidy up the discovery logs,updating loops and selects
few objects renamings
removed a very noise debug log on the k8s discovery. It would be usefull
to show some summary rather than every update as this is impossible to
follow.
added most comments as debug logs so each block becomes self
explanatory.
when the discovery receiving channel is full will retry again on the
next cycle.
Signed-off-by: Krasi Georgiev <kgeorgie@redhat.com>
* add noop logger for the SD manager tests.
Signed-off-by: Krasi Georgiev <kgeorgie@redhat.com>
* spelling nits
Signed-off-by: Krasi Georgiev <kgeorgie@redhat.com>
Especially for Kubernetes SD, this fixes a bug where the rendered
configuration says "api_server: null", which when read back is not
interpreted as an un-set API server (thus the default is not applied).
Signed-off-by: Julius Volz <julius.volz@gmail.com>
