Is RQL still a valid choice in 2022?

[bademux]

NO. no libraries. no one uses it, as it is not readable and not flexible.

[luckv]

Thank you, having a standard way to encode a complex query in a url, could have been great. Anyway... But could you help me and point me to some good alternatives? What is the industrial standard to query a database behind a rest api?

[bademux]

IMHO, one should not expose DB as rest. DB is not a microservice itself, but a part of microservice. For complex requests I would use POST + domain specific json.

[thjaeckle]

I love the simplicity and the possibility to add RQL queries to a URL. The Eclipse Ditto project, which I am contributing to, makes heavy use of (a subset) of the RQL expressions defined by this project in order to:

• formulate "search" queries (mapping to MongoDB)
• defining "conditions" (e.g. to conditionally retrieve/update "digital twins")
• defining "filters" (e.g. to subscribe to changes of "digital twins" matching a certain RQL based query)
• ...

Of course it would be nicer if RQL would be a standard, but we can live without it being one. The Ditto project built its own RQL (subset) parser in Java/Scala:

• https://github.com/eclipse-ditto/ditto/tree/master/rql/parser
• https://central.sonatype.com/artifact/org.eclipse.ditto/ditto-rql-parser/3.3.0

And we added 2 more predicates not defined in the original RQL:

• like (for searching with wildcards)
• ilike (for case insensitive searching with wildcards)

So my suggestion would be to make your own conclusions whether or not RQL is useful for you.

Here is yet another adoption of RQL I found "in the wild": https://connect.cloudblue.com/community/developers/api/rql/ They even provide a JS library: https://github.com/cloudblue/javascript-rql

So it is definitely used, however more tooling/libraries and a more "official" standard would of course be great to have.