Yōzefu query language.

Yōzefu uses a home-made query language inspired of the SQL syntax to search for kafka records. The BNF-like grammar is available here. here are some examples of queries:

1. The 20 first records on partition 2 where the key contains foo:

from begin 
partition == 2 
and key contains "foo" 
limit 20

2. Records where the offset is greater or equal than 3_460, only on partition 1 and 4, the json value must have a property album.title equal to Virtue:

from begin where
(partition == 1 || partition == 4)
and offset >= 3_460
and value.album.title == "Virtue"

3. Among the last 500 records, list the records where the size is bigger than 5Mb:

from end - 500
size > 5_000_000

4. Is there a record that contains release during a specific time range?

from "2024-11-23T12:00:00.000+01:00"
where timestamp between "2024-11-23T12:00:00.000+01:00" and "2024-11-23T15:00:00.000+01:00"
value contains "release"

5. Records where the md5(key) is equals to the user-provided parameter. A search filter must be implemented for this example.

from begin md5-key-equals-to("d131dd02c5e6eec4693d9a0698aff95c2fcab58712467eab4004583eb8fb7f89")