return as environment variable

[waleedsamy]

i use JSON.sh as curl 'http://conf.com/conf/config_20150920_test.json' | ./JSON.sh -l -p -b -s and it work greet and it return result like

["storage","mysql","u_db","database"]   "dev"
["storage","mysql","u_db","username"]   "user"
["storage","mysql","u_db","password"]   "123@1"
["storage","mysql","u_db","internal_ip"]    "10.176.192.120"
["storage","mysql","u_db","internal_port"]  3306
["storage","mysql","a","database"]  "a"
["storage","mysql","a","username"]  "user"
["storage","mysql","a","password"]  "122a@1"

but what if add config param to determine how output look like and go with exporting this variables as env variables like

storage_mysql_u_db_internal_port=3306
storage_mysql_a_database=a
storage_mysql_a_username=user
storage_mysql_a_password=122a@1

which make it easy to be evaluated with eval as environment variable.

[Tomaskom-cz]

Not exactly what you're asking for, but I use the following two functions for extracting values from the JSON.sh output:

#function to get value of specified key
#returns empty string if not found
#warning - does not validate key format (supplied as parameter) in any way, simply returns empty string for malformed queries too
#usage: VAR=$(getkey foo.bar) #get value of "bar" contained within "foo"
#       VAR=$(getkey foo[4].bar) #get value of "bar" contained in the array "foo" on position 4
#       VAR=$(getkey [4].foo) #get value of "foo" contained in the root unnamed array on position 4
function getkey {
    #reformat key string (parameter) to what JSON.sh uses
    KEYSTRING=$(sed -e 's/\[/\"\,/g' -e 's/^\"\,/\[/g' -e 's/\]\./\,\"/g' -e 's/\./\"\,\"/g' -e '/^\[/! s/^/\[\"/g' -e '/\]$/! s/$/\"\]/g' <<< "$@")
    #extract the key value
    FOUT=$(grep -F "$KEYSTRING" <<< "$JSON_PARSED")
    FOUT="${FOUT#*$'\t'}"
    FOUT="${FOUT#*\"}"
    FOUT="${FOUT%\"*}"
    echo "$FOUT"
}

#function returning length of array
#returns zero if key in parameter does not exist or is not an array
#usage: VAR=$(getarrlen foo.bar) #get length of array "bar" contained within "foo"
#       VAR=$(getarrlen) #get length of the root unnamed array
#       VAR=$(getarrlen [2].foo.bar) #get length of array "bar" contained within "foo", which is stored in the root unnamed array on position 2
function getarrlen {
    #reformat key string (parameter) to what JSON.sh uses
    KEYSTRING=$(sed -e '/^\[/! s/\[/\"\,/g' -e 's/\]\./\,\"/g' -e 's/\./\"\,\"/g' -e '/^$/! {/^\[/! s/^/\[\"/g}' -e '/^$/! s/$/\"\,/g' -e 's/\[/\\\[/g' -e 's/\]/\\\]/g' -e 's/\,/\\\,/g' -e '/^$/ s/^/\\\[/g' <<< "$@")
    #extract the key array length - get last index
    LEN=$(grep -o "${KEYSTRING}[0-9]*" <<< "$JSON_PARSED" | tail -n -1 | grep -o "[0-9]*$")
    #increment to get length, if empty => zero
    if [ -n "$LEN" ]; then
        LEN=$(($LEN+1))
    else
        LEN="0"
    fi
    echo "$LEN"
}

It expects the JSON.sh to be run with the -l flag and output stored in the variable $JSON_PARSED.

Also, using eval as you suggested can be dangerous if the output is improperly escaped. For example, string "; rm -rf /" in the JSON data could lead to disaster.

[decibel]

So how about adding these to JSON.sh itself? That way you could source it, parse the json once and query away.

[decibel]

Also, how would you get a list of keys in an object?

[Tomaskom-cz]

Depends on the format you'd like. If the subset of JSON structure is OK for you, just use it without the -l option and specify a "path" to the object in question. In this case, my code snippet should give you this substructure.
If you really want a simple list of strings, you could re-parse this subset with JSON.sh and just extract (grep + regex) the first key strings on each line from the output, removing duplicates.

[gnadelwartz]

Hi,

I also was looking for a solution to "slurp" JSON.sh output into an bash array.
if you output only the leafs with JSON.sh -s -b -n this will do the trick:

source <( printf 'declare -A JSON=( %s )' "$(JSON.sh -s -b -n <input | sed  -E -e 's/\t/=/g' -e 's#\\#\\\\#g')" )

this will be sourced "in place" as:

declare -A JSON=( ["ok"]="true" ["result",0,"update_id"]=146860800 ["result",0,"message","message_id"]=6541 ["result",0,"message","text"]="\\ud83d\\ude02\\ud83d\\ude1d\\ud83d\\udc4c\\u263a\\u2764\\ud83d\\ude15\\ud83d\\ude08#\\u20e3\\ud83c\\udf0f\\ud83c\\udf89\\ud83d\\ude4a\\ud83d\\ude49\\u2615\\ud83d\\ude80\\u2708\\ud83d\\ude82\\ud83d\\udcaf\\u2714\\u303d\\ud83d\\udd1a" ["result",0,"message","from","id"]=123456789 ["result",0,"message","from","is_bot"]="false" ["result",0,"message","from","first_name"]="Kay" ["result",0,"message","from","last_name"]="M" ["result",0,"from","username"]="Gnadelwartz" ["result",0,"message","from","language_code"]="de" ["result",0,"message","chat","id"]=123456789 ["result",0,"message","chat","first_name"]="Test" ["result",0,"message","chat","last_name"]="Bot" ["result",0,"message","chat","username"]="BotTest" ["result",0,"message","chat","title"]="BotTestTitle" ["result",0,"message","chat","type"]="private" ["result",0,"message","date"]=1555822879 )

Now you can use bash array syntax to access the values:

echo ${JSON[ok]}
true

echo ${JSON["result",0,"message","message_id"]}
6541

echo ${JSON["result",0,"update_id"]}
146860800

echo ${JSON["result",0,"message","from","username"]}
Gnadelwartz

echo ${JSON["result",0,"message","photo",4,"file_id"]}
AgADAgADL6oxG-Gw4EndCWGl2WUfUo1pXw8ABDsKqM0vfngJavgDAAEC

In bashbot this makes parsing and assigning JSON five times faster

In case you want to ask how to iterate over the array, see https://stackoverflow.com/questions/3112687/how-to-iterate-over-associative-arrays-in-bash