Bash脚本以json格式打印输出

Question

I'm trying to curl a webpage and does some processing to it and in final i am trying to print in json format.(which actually needs to be in mongodb input)

so the input (which is read though curl) is

Input:

brendan google engineer
stones microsoft chief_engineer
david facebook tester

for the kind of processing, i'm assigning values to the variables ($name, $emloyer, $designation)

my final command which converts to json is,

echo [{\"Name\":\"$name\"},{\"Employer\":\"$employer\"},{\"dDesignation\":\"$designation\"}]

The current output is,

[{"Name":"brendan","Employer":"google","Designation":"engineer"}]
[{"Name":"stones","Employer":"microsoft","Designation":"chief_engineer"}]
[{"Name":"david","Employer":"facebook","Designation":"tester"}]

but, i want the output in the same line separated by comma and square brackets in the start and end (not on every lines)

Expected output:

  [{"Name":"brendan","Employer":"google","Designation":"engineer"},{"Name":"stones","Employer":"microsoft","Designation":"chief_engineer"},
    {"Name":"david","Employer":"facebook","Designation":"tester"}]

any suggestions.

Answer 1

Conventional text-processing tools can't do this right for the general case. There are a bunch of corner cases to JSON -- nonprintable and high-Unicode characters (and quotes) need to be escaped, for instance. Use a tool that's actually built for the job, such as jq :

---

jq -n -R '
[
  inputs |
  split(" ") |
  { "Name": .[0], "Employer": .[1], "Designation": .[2] }
]' <<EOF
brendan google engineer
stones microsoft chief_engineer
david facebook tester
EOF

...emits as output:

[
  {
    "Name": "brendan",
    "Employer": "google",
    "Designation": "engineer"
  },
  {
    "Name": "stones",
    "Employer": "microsoft",
    "Designation": "chief_engineer"
  },
  {
    "Name": "david",
    "Employer": "facebook",
    "Designation": "tester"
  }
]

Answer 2

Something like this?

sep='['
curl "...whatever..." |
while read -r name employer designation; do
    printf '%s{"Name": "%s", "Employer": "%s", "Designation": "%s"}' "$sep" "$name" "$employer" "$designation"
    sep=', '
done
printf ']\n'

I do agree that this is brittle and error-prone; if you can use a JSON-aware tool like jq , by all means do that instead.

Answer 3

If you have access to jq 1.5 or later, then you can use inputs and may wish to consider using splits(" +") in case the tokens might be separated by more than one space:

jq -n -R '
  [inputs
   | [splits(" +")]
   | { "Name": .[0], "Employer": .[1], "Designation": .[2] }]'

If you do not have ready access to jq 1.5 or later, then please note that the following will work with jq 1.4:

jq -R -s '
  [split("\n")[]
   | select(length>0)
   | split(" ")
   | { "Name": .[0], "Employer": .[1], "Designation": .[2] }]'