如何优化jq输出

Question

I have a json file. A simple example looks like:

[
{
  "host": "a.com",
  "ip": "1.2.2.3",
  "port": 8,
  "name":"xyz"
},
{
  "host": "b.com",
  "ip": "2.5.0.4",
  "port": 3,
  "name":"xyz"

},
{
  "host": "c.com",
  "ip": "9.17.6.7",
  "port": 4,
  "name":"xyz"
}
]

I want to extract the "host" and "ip" value and add them in a comma separated values file. Each record in a line as follows:

a.com,1.2.2.3
b.com,2.5.0.4
c.com,9.17.6.7

I installed jq library to parse the json file. I executed this command:

cat test.json | jq '.[] | {host: .host, ip: .ip}'

The output I get is as the following:

{
  "host": "a.com",
  "ip": "1.2.2.3"
}
{
  "host": "b.com",
  "ip": "2.5.0.4"
}
{
  "host": "c.com",
  "ip": "9.17.6.7"
}

Is there any way I can extract the output as I want? This output that jq produced require additional script to parse it and save the values as I want in csv format, one item in a line.

Answer 1

To remove quotes:

$ cat test.json | jq -r '.[] | [ .host, .ip ] | @csv' | sed 's/"//g'
a.com,1.2.2.3
b.com,2.5.0.4
c.com,9.17.6.7

If using OS X, use Homebrew to install GNU sed .

Answer 2

Use the @csv format to produce CSV output from an array of the values.

cat test.json | jq -r '.[] | [.host, .ip] | @csv'

The -r option is needed to get raw output rather than JSON, which would wrap an extra set of quotes around the result and escape the quotes that surround each field.