The interactive mode that qq has is really slick. I didn't torture test it, but it worked pretty smoothly with a quick test.
I see that the XML support is implemented using the same library as rq. This definitely has some problems, because the data model of XML does not map very cleanly onto JSON. In particular, I recall that I had problems using mxj to marshal arrays, and had to use this[2] ugly hack instead. qq seems to have done this a little more cleanly[3]. I may just have to lift this particular trick.
I definitely found CSV output to be challenging. Converting arbitrary JSON style data into something table shaped is pretty tricky. This[4] is my attempt. I have found it works well enough, though it isn't perfect.
I can also see that qq hasn't yet run into the byte order marker problem with CSV inputs yet. Might want to check out spkg/bom[5].
One final breadcrumb I'll drop - I drew a lot of inspiration for rq's input parsers from conftest[6]. That may be a good resource to find more formats and see specific usage examples of them.
Thanks for sharing! It's really interesting to see some of the convergent evolution between rq and qq.
0 - https://git.sr.ht/~charles/rq
1 - https://www.openpolicyagent.org/docs/latest/policy-language/
2 - https://git.sr.ht/~charles/rq/tree/c67df633c0438763956ff8646...
3 - https://github.com/JFryy/qq/blob/2f750f04def47bec9be100b7c89...
4 - https://git.sr.ht/~charles/rq/tree/c67df633c0438763956ff8646...
5 - github.com/spkg/bom
rq was shared with me yesterday and just wanted to say it's very impressive, I had heard of OPA/Gatekeeper and have looked into Rego before for policy assertions w/ terraform but I was not aware the language was so expressive until I saw rq. Also the amount of codecs rq supports and quality of them is really great.
It is really neat seeing a lot tools solve a similar problem in such unique ways (especially the case with rq) and has been a lot of fun reading your experiences here. Thanks for sharing your experiences and expertise with the de-serializing/serializing content - It is really cathartic to hear you mention the challenges you solved with xml and csv. I really like how you solved for CSV output/input and the conditions on the input data you chose for evaluating it makes a lot of sense and is really comprehensive, it bothered me too since the content would either need to be a matrix or a slice of maps but seeing as jq has string formatting that can convert things to csv and @tsv - I was at a bit of a standstill of how to approach.
Thanks so much for the bread crumbs I look forward to reading this in more detail over the week/weekend :)
Rego is “for” those authz cases like the ones you mentioned in the sense that it’s definitely designed with those in mind, and I do think it does a good job for those needs. OPA itself is definitely geared for use as a microservice or container sidecar, talking over the wire. That’s kinda hard to use in a shell script though.
Once I learned it I found myself using opa eval for searching and transforming data, eventually so much so that I made a shell script called “rq” that was basically opa eval -I -f pretty… the rest is history.
2 nifty tools for querying semistructured data!
$ qq tests/test.hcl | jq | qq -o yaml
app_name: SimpleApp
database:
- host: localhost
password: password
port: 5432
username: admin
... - *qq* is not a full *jq/\*q* replacement and comes with idiosyncrasies from the underlying gojq library
I presume like pandoc, the goal is to use an internal model to reduce the M*N complexity of format transcoding to M+N.
But when I look at the tests for this (and Dasel and rq also mentioned here), I see very little. jq seems to have much more. Perhaps I'm missing them.
Which leads to some side/related comments...
A great project would be to build a transcoded test suite that all these tools could run against. It wouldn't be hard to generate.
Also, while go is a great language, I think pandoc gets a lot of benefit from implementing the internal model in haskell. Pandoc has a much harder problem because there's a lot more variability and less structure in the formats, so it should be doable for formats.
Now that you mention it, it would be nice to support a multi output mode in the cli as well. Using the codec library should achieve a similar M+N complexity if I am not mistaken.
[0] https://github.com/JFryy/qq/actions/runs/9654023860/job/2662...
qq currently supports hcl/tf, csv, ini, json, toml, xml and yaml. On the roadmap there are more to come soon such as protobuff, html. as it currently stands yq and qq don't support all the same formats as one another. A few examples:
- qq supports hcl but yq does not.
- yq supports lua, qq does not.
- qq and yq have different quirks in marshalling and unmarshalling data. For instance yq only supports toml output with scalars and on the other hand there's a lot of room for refinement with qq's encodings as of the moment.
qq's goal is to have a very comprehensive set of encodings many of which are yet to be included or represented in a single tool (qq will not cover most binary formats however). It also has a interactive query mode with auto-complete which is pretty handy on top of having a unique and growing set of formats supported.