How to use `jq` in a shell pipeline?

shell pipe jq
mgalgs picture mgalgs · Oct 20, 2015 · Viewed 83.7k times · Source

I can't seem to get jq to behave "normally" in a shell pipeline. For example:

$ curl -s https://api.github.com/users/octocat/repos | jq | cat

results in jq simply printing out its help text*. The same thing happens if I try to redirect jq's output to a file:

$ curl -s https://api.github.com/users/octocat/repos | jq > /tmp/stuff.json

Is jq deliberately bailing out if it determines that it's not being run from a tty? How can I prevent this behavior so that I can use jq in a pipeline?

* (I realize this example contains a useless use of cat; it's for illustration purposes only)

Answer

chepner picture chepner · Oct 20, 2015

You need to supply a filter as an argument. To pass the JSON through unmodified other than the pretty printing jq provides by default, use the identity filter .:

curl -s https://api.github.com/users/octocat/repos | jq '.' | cat

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