通过BASH中的JSON文件读取和循环

Question

I've got a JSON file (see below) called department_groups.json.

Essentially if I gave an argument of commercial I'd like it to return:

commercial-team@domain.com

commercial-updates@domain.com

Can anyone guide/help me with doing this?

{
    "legal": {
        "google_groups":[
            ["Legal", "legal@domain.com"],
            ["Legal Team", "legal-team@domain.com"],
            ["Compliance Checks", "compliance@domain.com"]
        ],
        "samba_groups": ""
     },
    "commercial":{
        "google_groups":[
            ["Commercial Team", "commercial-team@domain.com"],
            ["Commercial Updates", "commercial-updates@domain.com"]
        ],
        "samba_groups": ""  
    },
    "technology":{
        "google_groups":[
            ["Technology", "technology@domain.com"],
            ["Incidents", "incidents@domain.com"]
        ],
        "samba_groups": ""
    }
}

Answer 1

This returns the second element in each array in the google_groups property of the commercial property:

jq --arg key commercial '.[$key].google_groups | .[] | .[1]' file

Use jq -r to output in "raw" format (lose the double quotes).

$ key=commercial
$ jq -r --arg key "$key" '.[$key].google_groups | .[] | .[1]' file
commercial-team@domain.com
commercial-updates@domain.com

I used --arg in these examples to show how it is used, optionally with a shell variable. If, on the other hand, commercial was just a fixed string, then you could simplify:

jq -r '.commercial.google_groups | .[] | .[1]' file

To process each line of the output, you can just use a shell while read loop:

key=commercial
while read -r email; do
  echo "$email"
  # process each email individually here
done < <(jq -r --arg key "$key" '.[$key].google_groups | .[] | .[1]' file)

Here I am using a process substitution <() , which acts like a file that can be processed by the shell. One advantage of doing this, over using a pipe, is that no subshell is created. Among other things, this means that the variables used within the loop remain in scope after the while block, so you can use them later.

If you prefer to use a pipe, just remove the part after done and move the command up to the first line:

jq ... | while read -r email; do # etc.

Answer 2

As @TomFenech noted, the requirements are somewhat unclear, but if it's the email addresses you want, the following variant of his answer may be of interest:

key=commercial
$ jq -r --arg key "$key" '.[$key].google_groups[][] | select(test("@"))' department_groups.json
commercial-team@domain.com
commercial-updates@domain.com