How to convert a json response into yaml in bash

Question

I read data from a json file with jq. I wanna append the results into a yaml file, but I dont get it working. I am quite new to shell programming. My goal is to append that

Answer 1

I've used ruby to write my json content into yaml.

As for your example, it can be achieved like this:

cat $DEFAULTS_FILE | jq .users | ruby -ryaml -rjson -e 'puts YAML.dump(JSON.parse(STDIN.read))' > my.yml

Answer 2

function yaml_validate {
  python -c 'import sys, yaml, json; yaml.safe_load(sys.stdin.read())'
}

function yaml2json {
  python -c 'import sys, yaml, json; print(json.dumps(yaml.safe_load(sys.stdin.read())))'
}

function yaml2json_pretty {
  python -c 'import sys, yaml, json; print(json.dumps(yaml.safe_load(sys.stdin.read()), indent=2, sort_keys=False))'
}

function json_validate {
  python -c 'import sys, yaml, json; json.loads(sys.stdin.read())'
}

function json2yaml {
  python -c 'import sys, yaml, json; print(yaml.dump(json.loads(sys.stdin.read())))'
}

More Bash tricks at http://github.com/frgomes/bash-scripts

Answer 3

I'm not sure what rules you're using to get to your expected result. It seems like you're randomly applying different rules to how the values are being converted.

As I understand it, scalar values are just output as is (with potential encoding), objects are output as key/value pairs, and array objects are output with a - for every item. The indentation associates what's part of what.

So based on those rules if you're going to use jq:

def yamlify:
    (objects | to_entries[] | (.value | type) as $type |
        if $type == "array" then
            "\(.key):", (.value | yamlify)
        elif $type == "object" then
            "\(.key):", "    \(.value | yamlify)"
        else
            "\(.key):\t\(.value)"
        end
    )
    // (arrays | select(length > 0)[] | [yamlify] |
        "  - \(.[0])", "    \(.[1:][])"
    )
    // .
    ;

Then to use it, add it to your .jq file and use it:

$ jq -r yamlify input.json
users:
  - name:       pi
    gecos:      Hypriot Pirate
    sudo:       ALL=(ALL) NOPASSWD:ALL
    shell:      /bin/bash
    groups:     users,docker,video
    plain_text_passwd:  pi
    lock_passwd:        false
    ssh_pwauth: true
    chpasswd:
        expire: false
  - name:       admin
    gecos:      Hypriot Pirate
    sudo:       ALL=(ALL) NOPASSWD:ALL
    shell:      /bin/bash
    primary-group:      users
    groups:     users,docker,adm,dialout,audio,plugdev,netdev,video
    ssh-import-id:      None
    plain_text_passwd:  pi
    lock_passwd:        true
    ssh_pwauth: true
    chpasswd:   {expire: false}
    ssh-authorized-keys:
      - ssh-rsa abcdefg1234567890 YOUR_KEY@YOURHOST.local

---

Here's another variation that aligns the values

def yamlify2:
    (objects | to_entries | (map(.key | length) | max + 2) as $w |
        .[] | (.value | type) as $type |
        if $type == "array" then
            "\(.key):", (.value | yamlify2)
        elif $type == "object" then
            "\(.key):", "    \(.value | yamlify2)"
        else
            "\(.key):\(" " * (.key | $w - length))\(.value)"
        end
    )
    // (arrays | select(length > 0)[] | [yamlify2] |
        "  - \(.[0])", "    \(.[1:][])"
    )
    // .
    ;

$ jq -r yamlify2 input.json
users:
  - name:               pi
    gecos:              Hypriot Pirate
    sudo:               ALL=(ALL) NOPASSWD:ALL
    shell:              /bin/bash
    groups:             users,docker,video
    plain_text_passwd:  pi
    lock_passwd:        false
    ssh_pwauth:         true
    chpasswd:
        expire:  false
  - name:                 admin
    gecos:                Hypriot Pirate
    sudo:                 ALL=(ALL) NOPASSWD:ALL
    shell:                /bin/bash
    primary-group:        users
    groups:               users,docker,adm,dialout,audio,plugdev,netdev,video
    ssh-import-id:        None
    plain_text_passwd:    pi
    lock_passwd:          true
    ssh_pwauth:           true
    chpasswd:             {expire: false}
    ssh-authorized-keys:
      - ssh-rsa abcdefg1234567890 YOUR_KEY@YOURHOST.local

Answer 4

I suggest using yq with -y option

$ pip3 install yq # requires jq

$ cat in.json | yq -y
users:
  - name: pi
    gecos: Hypriot Pirate
    sudo: ALL=(ALL) NOPASSWD:ALL
    shell: /bin/bash
    groups: users,docker,video
    plain_text_passwd: pi
    lock_passwd: 'false'
    ssh_pwauth: 'true'
    chpasswd:
      expire: false
  - name: admin
    gecos: Hypriot Pirate
    sudo: ALL=(ALL) NOPASSWD:ALL
    shell: /bin/bash
    primary-group: users
    groups: users,docker,adm,dialout,audio,plugdev,netdev,video
    ssh-import-id: None
    plain_text_passwd: pi
    lock_passwd: 'true'
    ssh_pwauth: 'true'
    chpasswd: '{expire: false}'
    ssh-authorized-keys:
      - ssh-rsa abcdefg1234567890 YOUR_KEY@YOURHOST.local

Answer 5

With yq version 3.3.2:

cat $DEFAULTS_FILE | yq r -P -

yq a yaml wrapper for jq

r read

-P --prettyPrint

- from STDIN

Answer 6

Another oneliner:

python -c 'import yaml, sys; print(yaml.dump(yaml.load(open(sys.argv[1])), default_flow_style=False))' input.json

(exploiting the fact that valid json is also valid yaml)

And yaml to json:

python -c 'import yaml, json, sys; print(json.dumps(yaml.load(open(sys.argv[1])), indent=2))' input.yaml