Useful JQ programs

comments.md

I use split-newlines-and-parse-stringified-json.jq to make json, usually from logs, more readable:

It recursively:

• splits strings containing newlines into arrays
• expands escaped tabs into spaces
• expands stringified json

$ echo '{
  "foo": 42,
  "bar": [
    "{\"jq\": \"is fun\"}"
  ],
  "mostly": "[true]",
  "and": "look\\n{\"more\":\"json\"}\\n!"
}' |
jq '
def fromjson_obj:
    with_entries(. as $s
        | try (.value = (.value | fromjson)) catch $s
    );

def fromjson_arr:
    map(. as $s | try fromjson catch $s);

def split_newlines:
  if type=="string" then split("\t") | join("    ") | if contains("\n") then split("\n") | split_newlines else . end
  elif type=="object" then fromjson_obj | map_values(split_newlines)
  elif type=="array" then fromjson_arr | map(split_newlines)
  else .
  end;

split_newlines
'

{
  "foo": 42,
  "bar": [
    {
      "jq": "is fun"
    }
  ],
  "mostly": [
    true
  ],
  "and": [
    "look",
    {
      "more": "json"
    },
    "!"
  ]
}

split-newlines-and-parse-stringified-json.jq

def fromjson_obj_hack:
    with_entries(. as $s
        | try (.value = (.value | fromjson)) catch $s
    );

def fromjson_arr_hack:
    map(. as $s | try fromjson catch $s);

def clean_string:
  split("\t") | join("    ") | if contains("\n") then split("\n") else . end;

def split_newlines:
  if type=="string" then clean_string
  elif type=="object" then fromjson_obj_hack | map_values(split_newlines)
  elif type=="array" then fromjson_arr_hack | map(split_newlines)
  else .
  end;

split_newlines