I don't think that node is bad, but it's simply another dependency you have to worry about. Most devs likely won't have node pre-installed. Having a no-dependency binary is a great thing.
Because if you are not developing in node, and don't have any other node based software, yet another runtime, its package manager(s), and dependencies are unwanted additions to a system.
Node is great, and a port of jq to node would be awesome (someone once hinted at such a port, but I've lost track of it).
But jq also has libjq, a C library. And jq uses a copy-on-write, reference counted representation of JSON values, which is, for example, inherently thread-safe (though jq isn't using atomic operations for refcount management yet). The library is easy to use and powerful.
Ultimately the main thing I love about jq (and why I contribute to it) is the jq language itself. It reminds me of my one-time favorite, Icon. But in a world where C is still the champion of systems programming (until Rust takes over?), it's real handy to have a C JSON library _and_ a functional DSL that's easy to invoke from C.
If percol is based on aut-fu, then it's probably not that good. The screenshot shows auto-fu, I know that zsh-plugin, but it's really messy and does very aggressive auto-completion (erasing your previous input).
I'd rather use fish-shell instead.
no percol is not shell plugin, but a simple cmdline util used in a pipeline, I suggest you take a look. I understand that animation on the website is a little bit confusing though.
This script drops you into a coffescript REPL with the json loaded into memory under the variable j.
I find it nice to be able to loop the data, define new subsets, filter it with functions, etc.
It was a 10 minute slap-job to get it together, so it does barf on particularly large datasets. The obvious reason is that it serialises the JSON into an argument for a child process. Shouldn't be too hard to resolve if anyone feels like it.
I've been using this tool to build a bash library for a JSON/REST API and I can attest to its usefulness. Filter huge data sets down to just the fields you want, mutate, select, search, filter. Most everything I've wanted to do this can handle. Plus it's fast and dead simple to install. Kudos to the devs for this fantastic tool that I hope will soon be part of the default CL toolset across the board.
I'm using this tool with curl in scripts calling AWS api. Looking for an id of an object (security group, autoscaling group etc.) with its name and referencing it afterward in another command.
I've been using it for the exact same thing. One difficulty that I had was that you need to use the raw option, "jq -r" for string output without quotes, but I was looking at the query language documentation and not finding it.
EDIT: here is one I used. Given VOLUME_ID, gets the most recent snapshot-id.
Hey, me too! It's pretty awesome, although the documentation/examples aren't as great as they could be - it took me some time to figure out how to properly parse arrays, and I'm still not sure how to actually do what I want to do (I want to convert an array of two instance objects into an array with just two instance IDs.
I've been using this to transform the output of ElasticBeanstalk environment queries into things I can feed into environment updates since moving between versions is a PITA. Should post that code sometime...
Does anyone know of a similar tool for XML? In particular, it would be cool to have a useful way to run xpath, and maybe xquery, from the command line. The tools I've found have unfortunate interfaces, e.g. they won't read XML from stdin.
Most of the JSON conversions from XML get it all wrong though. XML is not really an object (dict, hash) based meta-schema. It's an array-based meta-schema. XML->JSON conversions should look something like this:
I am not a huge fan of PHP, but you can do some useful stuff to XML using the PHP command line tool, provided you have the right libraries installed. I have run into situations where the package manager on a machine I'm using doesn't have an up to date xmlstartlet or xmllint, and have tidily gotten around this problem using PHP.
I've been using it for over a year - especially with AWS CLI, but, I'm a little displeased that it only has the query feature (duh) and does not have a little more like merging JSONs (I think it only has appending). Another issue is that I wasn't able to find release notes for v1.4 - what's new since v1.3? There other similar tools, but they require node, Python packages, etc. jq really is installed with one command and no dependencies.
Yeah, I'm a schmuck, I forgot to add release notes :(
I've been thinking I need to do a 1.4.1 release just for that!
(Plus we're getting some cool new features suddenly. @wtlangford (on github) is working on regexps, for example. Maybe a 1.4.1 so soon would be justified.)
You should be able to do some pipe fu and carry out some form of merging via bash. I mostly use it for making our output more readable or producing CSV style reports with the filtered data. Its filters are probably the biggest feature, at least in my mind.
Sorry for not being clear. I meant a merge in the form of {"a": 1, "b": 2, "c": 3} merged with {"b": 20} returning {"a": 1, "b": 20, "c": 3}. Like Python's update() or PHP's array_replace_recursive() although PHP's a little richer.
Been using jq for a while now. Probably since the last hn post. My biggest gripe with jq is the name and asking for help on stack overflow - the jq tag is an alias to the jquery tag. Someone with tag edit level rep should really fix that.
I've been using this for a while, and it's wonderful to parse the output from API calls requested via curl, as well as quickly checking a specific package.json field from the npm output. The --json flag is handy for the latter.
Thank you! When I clicked on the link I was fully expecting it to be written in Node and I was going to cry.