Write output to a file after piped to jq

Just calling jq without a filter will throw errors if stdout isn't a terminal

$ curl https://jsonplaceholder.typicode.com/posts/1 | jq > test.txtjq - commandline JSON processor [version 1.5-1-a5b5cbe]Usage: jq [options] <jq filter> [file...]        jq is a tool for processing JSON inputs, applying the        given filter to its JSON text inputs and producing the[...]

Try jq '.' (i.e: pretty-print the input JSON):

$ curl https://jsonplaceholder.typicode.com/posts/1 | jq '.' > test.txt  % Total    % Received % Xferd  Average Speed   Time    Time     Time  Current                                 Dload  Upload   Total   Spent    Left  Speed100   292  100   292    0     0   1698      0 --:--:-- --:--:-- --:--:--  1707

Note that the filter is not really optional:

From man jq:

JQ(1)                                                                                JQ(1)NAME       jq - Command-line JSON processorSYNOPSIS       jq [options...] filter [files...]

According to the tip of the master branch... your described (and my observed) behaviour is not expected...

Older versions of jq have the following: (here)

if (!program && isatty(STDOUT_FILENO) && !isatty(STDIN_FILENO))  program = ".";

i.e: use a default filter if stdout is a TTY, and stdin is not a TTY.

This behaviour appears to be corrected in commit 5fe05367, with the following snippet of code:

if (!program && (!isatty(STDOUT_FILENO) || !isatty(STDIN_FILENO)))  program = ".";

My incantation:

$ cat config.json{    "ProgramSettings":    {        "version": "1.0"    },    "ProgramSecrets":    {        "AWS_ACCESS_KEY_ID": "",        "AWS_SECRET_ACCESS_KEY": ""    }}

assume you want remove object 'ProgramSecrets' from JSON file:

$ echo $(cat config.json | jq 'del(.ProgramSecrets)') > config.json$ cat config.json{ "ProgramSettings": { "version": "1.0" } }