Related to #12318 .
Allow using a PromQL expression for setting the offset, provided that:
the expression evaluates to a scalar
the expression does not contain vector selector (no TSDB access)
the expression does not call the info() function (no TSDB access)
the time() function is only called on the top level of the expression,
not inside a subquery
We'll call such expression a time expression.
During parsing we no longer set OriginalOffset field in sub-queries and
vector selectors, instead we set a new OriginalOffsetExpr field to the
time expression, even if the expression is a literal number.
Before evaluating the overall PromQL expression, the engine shall
evaluate the time expressions and set the OriginalOffset field in vector
selectors and subqueries to the calculated value. This makes the change
fairly non intrusive. Later we can change the code to start using the
expression more directly. Note: this prohibits using time() function
inside a sub-query as the evaluation time is not constant inside a
sub-query.
Signed-off-by: György Krajcsovits <gyorgy.krajcsovits@grafana.com>
Fixes UTF-8 aggregator label list items getting mutated with quote marks when String-ified.
Fixes quoted metric names not supported in metric declarations.
Fixes UTF-8 label names not being quoted when String-ified.
Fixes https://github.com/prometheus/prometheus/issues/15470
Fixes https://github.com/prometheus/prometheus/issues/15528
Signed-off-by: Owen Williams <owen.williams@grafana.com>
Co-authored-by: Bryan Boreham <bjboreham@gmail.com>
fix(utf8): ensure correct validation when legacy mode turned on
This depends on the included update of the prometheus/common dependency.
---------
Signed-off-by: Owen Williams <owen.williams@grafana.com>
The check fell into "this matcher equals vector selector's name" case when vector selector doesn't have a name and the matcher is an explicit matcher for an empty __name__ label.
To provide some context about why this is important: some downstream projects use the promql.Parse(expr.String()) to clone an expression's AST, and with this bug that matcher disappears in the cloning.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
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>
* Prettifier: Add spaces with non-callable keywords
I prefer to have a difference between, on one side: functions calls, end(), start(), and on the other side with, without, ignoring, by and group_rrigt, group_left.
The reasoning is that the former ones are not calls, while other are
functions. Additionally, it matches the examples in our documentation.
Signed-off-by: Julien Pivotto <roidelapluie@o11y.eu>
* Fix tests
Signed-off-by: Julien Pivotto <roidelapluie@o11y.eu>
* Implement Pretty() function for AST nodes.
Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>
This commit adds .Pretty() for all nodes of PromQL AST.
Each .Pretty() prettifies the node it belongs to, and under
no circustance, the parent or child node is touch/prettified.
Read more in the "Approach" part in `prettier.go`
* Refactor functions between printer.go & prettier.go
Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>
This commit removes redundancy between printer.go and prettier.go
by taking out the common code into separate private functions.
* Add more unit tests for Prettier.
Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>
* Add support for spliting function calls with 1 arg & unary expressions.
Signed-off-by: Harkishen-Singh <harkishensingh@hotmail.com>
This commit does 2 things:
1. It adds support to split function calls that have 1 arg and exceeds the max_characters_per_line
to multiple lines.
2. Splits Unary expressions that exceed the max_characters_per_line. This is done by formatting the child node
and then removing the prefix indent, which is already applied before the unary operator.
This creates a new `model` directory and moves all data-model related
packages over there:
exemplar labels relabel rulefmt textparse timestamp value
All the others are more or less utilities and have been moved to `util`:
gate logging modetimevfs pool runtime
Signed-off-by: beorn7 <beorn@grafana.com>
* Allow VectorSelector.String() without matchers
Previously this method was panicking because it was trying to allocate a
slice with capacity -1. There's nothing saying that VectorSelector
should have matchers, and it's actually prepared to have zero matcher
strings, so it's worth checking instead of panicking.
Signed-off-by: Oleg Zaytsev <mail@olegzaytsev.com>
This commit adds `@ <timestamp>` modifier as per this design doc: https://docs.google.com/document/d/1uSbD3T2beM-iX4-Hp7V074bzBRiRNlqUdcWP6JTDQSs/edit.
An example query:
```
rate(process_cpu_seconds_total[1m])
and
topk(7, rate(process_cpu_seconds_total[1h] @ 1234))
```
which ranks based on last 1h rate and w.r.t. unix timestamp 1234 but actually plots the 1m rate.
Signed-off-by: Ganesh Vernekar <cs15btech11018@iith.ac.in>
