PromQL Lexer and Parser

The goal of this project is to build a PromQL lexer and parser capable of parsing PromQL that conforms with Prometheus Query.

Example

To parse a simple instant vector selector expression:

``` rust use promql_parser::parser;

let promql = r#"httprequeststotal{environment=~"staging|testing|development",method!="GET"} @ 1609746000 offset 5m"#;

match parser::parse(promql) { Ok(ast) => println!("AST: {:?}", ast), Err(info) => println!("Err: {:?}", info), } ```

or you can directly run examples under this repo:

shell cargo run --example parser

This outputs:

rust AST: VectorSelector(VectorSelector { name: Some("http_requests_total"), matchers: Matchers { matchers: {Matcher { op: NotEqual, name: "method", value: "GET" }, Matcher { op: Re(staging|testing|development), name: "environment", value: "staging|testing|development" }, Matcher { op: Equal, name: "__name__", value: "http_requests_total" }} }, offset: Some(Pos(300s)), at: Some(At(SystemTime { tv_sec: 1609746000, tv_nsec: 0 })) })

PromQL compliance

This crate declares compatible with prometheus 0372e25, which is prometheus release 2.40 at Nov 29, 2022. Any revision on PromQL after this commit is not guaranteed.

Users

This parser is currently being used by the GreptimeDB and py-promql-parser.

If your project is using promql-parser feel free to make a PR to add it to this list.

Contributing

Contributions are highly encouraged!

Pull requests that add support for or fix a bug in a feature in the PromQL will likely be accepted after review.

Licensing

All code in this repository is licensed under the Apache License 2.0.

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be licensed as above, without any additional terms or conditions.