Parsing how question

[fredx181]

Trying to get some results in parsing (with bash) something like this:

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    "html_url": "https://github.com/whoamI/repo1",
    "description": "null",
    "fork": false,
--
    "html_url": "https://github.com/whoamI/repo2",
    "description": "blah",
    "fork": true,
--
    "html_url": "https://github.com/whoamI/repo3",
    "description": null,
    "fork": false,
--
    "html_url": "https://github.com/whoamI/repo4",
    "description": "null",
    "fork": true,
--

What I would like the outcome to be is: (only from where : "fork": false,):

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"html_url": "https://github.com/whoamI/repo1",
"html_url": "https://github.com/whoamI/repo3",

Tried some ways with a while read loop, but can't figure out how.

[MochiMoppel]

Trying to get some results in parsing (with bash)

You mean solely with bash shell commands?
OK, but then let's increase fun and speed and make it also compatible with ash and even dash:

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#! /bin/ash
OLD='
    "html_url": "https://github.com/whoamI/repo1",
    "description": "null",
    "fork": false,
--
    "html_url": "https://github.com/whoamI/repo2",
    "description": "blah",
    "fork": true,
--
    "html_url": "https://github.com/whoamI/repo3",
    "description": null,
    "fork": false,
--
    "html_url": "https://github.com/whoamI/repo4",
    "description": "null",
    "fork": true,
--'

LF="
"
while : ; do
	NEW=${OLD%$LF*description*false*}
	[ "$NEW" = "$OLD" ] && break || OLD=$NEW
	HTM=\"htm${NEW##*htm}$LF$HTM
done
echo "$HTM"

This would also work with bash/ash/dash but uses sed:

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echo $OLD | sed  's/false,/&\n/g' | sed -rn '/false,$/ s/(.*htm)(.*\/[^,]*)(.*)/\"htm\2,/p'

Requires bash, uses tac:

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echo "$OLD" | tac |
while read -r LINE; do
	[[ $LINE = *false* ]] && FOUND=1
	[[ $FOUND$LINE = 1*htm* ]] && echo "$LINE" && FOUND=
done

Note that this writes resulting lines in reverse order. Not an elegant solution anyway

[fredx181]

Many thanks ! @MochiMoppel Works very well.
I wouldn't have come to such compact code in a 100 years !

[puppy_apprentice]

I like grep:

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grep -B2 "\"fork\": false," data.txt | grep "html_url"

data.txt:

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    "html_url": "https://github.com/whoamI/repo1",
    "description": "null",
    "fork": false,
--
    "html_url": "https://github.com/whoamI/repo2",
    "description": "blah",
    "fork": true,
--
    "html_url": "https://github.com/whoamI/repo3",
    "description": null,
    "fork": false,
--
    "html_url": "https://github.com/whoamI/repo4",
    "description": "null",
    "fork": true,
--

[Burunduk]

This would also work with bash/ash/dash but uses sed:

Code: Select all

echo $OLD | sed  's/false,/&\n/g' | sed -rn '/false,$/ s/(.*htm)(.*\/[^,]*)(.*)/\"htm\2,/p'

Just a note: this snippet works because the echo command outputs the whole thing as a single line.

For a multi-line input this sed command could be used:

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echo "$OLD" | sed -n '/html_url/h;/false,/{g;p}'

However, sed is not a json parser.

As this is a "parsing how" question, maybe jq is a better answer.

For example, if you have something like this:

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bat repos.json
───────┬─────────────────────────────────────────────────────────────────
       │ File: repos.json
───────┼─────────────────────────────────────────────────────────────────
   1   │ [
   2   │   {
   3   │     "html_url": "https://github.com/whoamI/repo1",
   4   │     "description": "null",
   5   │     "fork": false
   6   │   },
   7   │   {
   8   │     "html_url": "https://github.com/whoamI/repo2",
   9   │     "description": "blah",
  10   │     "fork": true
  11   │   },
  12   │   {
  13   │     "html_url": "https://github.com/whoamI/repo3",
  14   │     "description": null,
  15   │     "fork": false
  16   │   },
  17   │   {
  18   │     "html_url": "https://github.com/whoamI/repo4",
  19   │     "description": "null",
  20   │     "fork": true
  21   │   }
  22   │ ]
───────┴─────────────────────────────────────────────────────────────────

you can run

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jq '.[] | select(.fork==false) | .html_url' repos.json

to get

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"https://github.com/whoamI/repo1"
"https://github.com/whoamI/repo3"