Bash and jq nested loops on json

问题

I try to use jq to parse a json file and use it in a bash script, but i'm having some difficulties. The json

[
{"annonce_id":"123","photos":["url_01"],"titre_slug":"slug1"},
{"annonce_id":"456","photos":["url_11","url_12"],"titre_slug":"slug2"},
{"annonce_id":"7890","photos":["url_31"],"titre_slug":"slug3"},
{"annonce_id":"1234","photos":["url_41"],"titre_slug":"slug4"},
{"annonce_id":"5678","photos":["url_51"],"titre_slug":"slug5"},
{"annonce_id":"90123","photos":["url_61"],"titre_slug":"slug6"}
]

The goal : For each line, retrieve annonce_id, titre_slug and photos in bash variables. Photos should be in an array, since it can contain 1 or more elements.

If i do a

jq -r '.[] | .annonce_id, .titre_slug, .photos'

on this data, i display the info, but i'd like to have it in bash variables (preferably named after the json fields), to use annonce_id and titre_slug, and iterate over photos.

Thanks

回答1:

There are many possible solutions in bash. Here's one that does NOT require mapfile (aka readarray):

while read -r annonce
do      
    read -r titre
    IFS=$'\t' read -r -a photos
    echo annonce="$annonce"
    echo titre="$titre"
    echo number of photos is ${#photos[@]}
done < <(jq -r '.[] | .annonce_id, .titre_slug, (.photos | @tsv)' input.json)

回答2:

#!/bin/bash
    json_file="/home/pruebas/file.json"
    while read line
     do
        if [ $(echo $line|grep annonce|wc -l) -gt 0 ]
            then
                var_annonce_id=$(echo $line |grep annonce |awk 'BEGIN {FS="\""}{print $4}')
                var_titre_slug=$(echo $line |grep annonce |awk 'BEGIN {FS="\]"}{print $2}' | awk 'BEGIN {FS="\""}{print $4}')
                var_photo_array=$(echo $line |grep annonce |awk 'BEGIN {FS="\["}{print $2}' |awk 'BEGIN {FS="\]"}{print $1}' |tr -d "\"" | sed s/"\,"/" "/g )
                echo "Annonce_id=$var_annonce_id"
                echo "Titre_slug=$var_titre_slug"
                echo "Photo Array=$var_photo_array"
        fi
    done < $json_file

来源：https://stackoverflow.com/questions/48324463/bash-and-jq-nested-loops-on-json