I'm a rookie wirh JQ.
I would like to merge 2 json files with JQ. But only for the present keys in first file.
First file (first.json)
{
"##locale": "en",
"foo": "bar1"
}
Second file (second.json)
{
"##locale": "en",
"foo": "bar2",
"oof": "rab"
}
I already tried.
edit: jq -n '.[0] * .[1]' first.json second.json
jq -s '.[0] * .[1]' first.json second.json
But the returned result is wrong.
{
"##locale": "en",
"foo": "bar2",
"oof": "rab"
}
"oof" entry should not be present.
Expected merged.
{
"##locale": "en",
"foo": "bar2"
}
Best regards.
And here's a one-liner, which happens to be quite efficient:
jq --argfile first first.json '. as $in | $first | with_entries(.value = $in[.key] )' second.json
Consider:
jq -n '.
| input as $first # read first input
| input as $second # read second input
| $first * $second # make the merger of the two the context item
| [ to_entries[] # ...then break it out into key/value pairs
| select($first[.key]) # ...and filter those for whether they exist in the first input
] | from_entries # ...before reassembling into a single object.
' first.json second.json
...which properly emits:
{
"##locale": "en",
"foo": "bar2"
}
Related
curl http://testhost.test.com:8080/application/app/version | jq '.version' | jq '.[]'
The above command outputs only the values as below:
"madireddy#test.com"
"2323"
"test"
"02-03-2014-13:41"
"application"
How can I get the key names instead like the below:
email
versionID
context
date
versionName
To get the keys in the order they appear in the original JSON use:
jq 'keys_unsorted' file.json
If you want the keys sorted alphanumerically, you can use:
jq 'keys' file.json
Complete example
$ cat file.json
{ "Created-By" : "Apache Maven", "Build-Number" : "", "Archiver-Version" : "Plexus Archiver", "Build-Id" : "", "Build-Tag" : "", "Built-By" : "cporter"}
$ jq 'keys_unsorted' file.json
[
"Created-By",
"Build-Number",
"Archiver-Version",
"Build-Id",
"Build-Tag",
"Built-By"
]
$ jq 'keys' file.json
[
"Archiver-Version",
"Build-Id",
"Build-Number",
"Build-Tag",
"Built-By",
"Created-By"
]
To get the keys on a deeper node in a JSON:
echo '{"data": "1", "user": { "name": 2, "phone": 3 } }' | jq '.user | keys[]'
"name"
"phone"
You need to use jq 'keys[]'. For example:
echo '{"example1" : 1, "example2" : 2, "example3" : 3}' | jq 'keys[]'
Will output a line separated list:
"example1"
"example2"
"example3"
In combination with the above answer, you want to ask jq for raw output, so your last filter should be eg.:
cat input.json | jq -r 'keys'
From jq help:
-r output raw strings, not JSON texts;
To print keys on one line as csv:
echo '{"b":"2","a":"1"}' | jq -r 'keys | [ .[] | tostring ] | #csv'
Output:
"a","b"
For csv completeness ... to print values on one line as csv:
echo '{"b":"2","a":"1"}' | jq -rS . | jq -r '. | [ .[] | tostring ] | #csv'
Output:
"1","2"
If your input is an array of objects,
[
{
"a01" : { "name" : "A", "user" : "B" }
},
{
"a02" : { "name" : "C", "user" : "D" }
}
]
try with:
jq '.[] | keys[]'
Oddly enough, the accepted answer doesn’t actually answer the Q exactly, so for reference, here is a solution that does:
$ jq -r 'keys_unsorted[]' file.json
echo '{"ab": 1, "cd": 2}' | jq -r 'keys[]' prints all keys one key per line without quotes.
ab
cd
Here's another way of getting a Bash array with the example JSON given by #anubhava in his answer:
arr=($(jq --raw-output 'keys_unsorted | #sh' file.json))
echo ${arr[0]} # 'Archiver-Version'
echo ${arr[1]} # 'Build-Id'
echo ${arr[2]} # 'Build-Jdk'
I start from a jsonlines file similar to this
{ "kw": "foo", "age": 1}
{ "kw": "foo", "age": 1}
{ "kw": "foo", "age": 1}
{ "kw": "bar", "age": 1}
{ "kw": "bar", "age": 1}
Please note each line is a valid json, but the whole file is not.
The output I'm seeking is an ordered list of keywords sorted by its occurrence. Like this:
[
{"kw": "foo", "count": 3},
{"kw": "bar", "count": 2}
]
I'm able to group and count the keywords using the slurp option
jq --slurp '. | group_by(.kw) | .[] | {kw: .[0].kw, count: . | length }'
Output:
{"kw":"bar","count":2}
{"kw":"foo","count":3}
But:
This is not sorted
This is not valid JSON array
A very stupid solution I've found, is to pass twice via jq :)
jq --slurp --compact-output '. | group_by(.kw) | .[] | {kw: .[0].kw, count: . | length }' sample.json \
| jq --slurp --compact-output '. | sort_by(.count)'
But I'm pretty sure someone smarter than me can find a more elegant solution.
This is not sorted
That is not quite correct, group_by(.foo) internally does a sort(.foo), so the results are shown in the sorted order of the field. See jq Manual - group_by(path_expression)
This is not valid JSON array
Just enclose the operation within [..] and also the leading . is optional. So just do
jq --slurp --compact-output '[ group_by(.kw)[] | {kw: .[0].kw, count: length } ]'
If you are referring to sort by the .count you can do a ascending sort and reverse
jq --slurp --compact-output '[ group_by(.kw)[] | {kw: .[0].kw, count: length }] | sort_by(.count) | reverse'
Lets say this is my array :
[
{
"name": "Matias",
"age": "33"
}
]
I can do this :
echo "$response" | jq '[ .[] | select(.name | test("M.*"))] | . += [.[]]'
And it will output :
[
{
"name": "Matias",
"age": "33"
},
{
"name": "Matias",
"age": "33"
}
]
But I cant do this :
echo "$response" | jq '[ .[] | select(.name | test("M.*"))] | . += [.[] * 3]'
jq: error (at <stdin>:7): object ({"name":"Ma...) and number (3) cannot be multiplied
I need to extend an array to create a dummy array with 100 values. And I cant do it. Also, I would like to have a random age on the objects. ( So later on I can filter the file to measure performance of an app .
Currently jq does not have a built-in randomization function, but it's easy enough to generate random numbers that jq can use. The following solution uses awk but in a way that some other PRNG can easily be used.
#!/bin/bash
function template {
cat<<EOF
[
{
"name": "Matias",
"age": "33"
}
]
EOF
}
function randoms {
awk -v n=$1 'BEGIN { for(i=0;i<n;i++) {print int(100*rand())} }'
}
randoms 100 | jq -n --argfile template <(template) '
first($template[] | select(.name | test("M.*"))) as $t
| [ $t | .age = inputs]
'
Note on performance
Even though the above uses awk and jq together, this combination is about 10 times faster than the posted jtc solution using -eu:
jq+awk: u+s = 0.012s
jtc with -eu: u+s = 0.192s
Using jtc in conjunction with awk as above, however, gives u+s == 0.008s on the same machine.
I have the following type of json:
{
"foo": "hello",
"bar": [
{
"key": "k1",
"val": "v1"
},
{
"key": "k2",
"val": "v2"
},
{
"key": "k3",
"val": "v3"
}
]
}
I want to output the following:
"hello", 1, "k1", "v1"
"hello", 2, "k2", "v2"
"hello", 3, "k3", "v3"
I am using jq to tranform this and the answer should also be with a jq transformation.
I am currently at:
echo '{"foo": "hello","bar": [{"key": "k1","val": "v1"},{"key": "k2","val": "v2"},{"key": "k3","val": "v3"} ]}' | jq -c -r '.bar[] as $b | [.foo, ($b | .key, .val)] | #csv'
Which gives me:
"hello","k1","v1"
"hello","k2","v2"
"hello","k3","v3"
How can I also get the index to show of the array element being parsed?
You could convert the array to entries to access the index and the value. Then you can build out the CSV rows.
$ jq -r '[.foo] + (.bar | to_entries[] | [.key+1,.value.key,.value.val]) | #csv' input.json
"hello",1,"k1","v1"
"hello",2,"k2","v2"
"hello",3,"k3","v3"
Assuming you have access to jq 1.5 and that the key/val keys are presented in that order:
jq -r '.foo as $foo
| foreach .bar[] as $i (0; .+1; [$foo, .] + [$i[]])
| #csv'
would produce:
"hello",1,"k1","v1"
"hello",2,"k2","v2"
"hello",3,"k3","v3"
The -r option is often used with #csv to convert the JSON string that would otherwise be produced by #csv into a comma-separated list of values.
If you really want to join with ", ", then it's a bit messier, but if you're not worried about the functionality that #csv provides, here's one way:
$ jq -r '"\"\(.foo)\"" as $foo
| foreach .bar[] as $i
(0; .+1; "\($foo), \(.), \($i | map("\"\(.)\"")|join(", "))")'
This produces:
"hello", 1, "k1", "v1"
"hello", 2, "k2", "v2"
"hello", 3, "k3", "v3"
If your jq does not have foreach then you could similarly use reduce, but it might be easier to upgrade.
curl http://testhost.test.com:8080/application/app/version | jq '.version' | jq '.[]'
The above command outputs only the values as below:
"madireddy#test.com"
"2323"
"test"
"02-03-2014-13:41"
"application"
How can I get the key names instead like the below:
email
versionID
context
date
versionName
To get the keys in the order they appear in the original JSON use:
jq 'keys_unsorted' file.json
If you want the keys sorted alphanumerically, you can use:
jq 'keys' file.json
Complete example
$ cat file.json
{ "Created-By" : "Apache Maven", "Build-Number" : "", "Archiver-Version" : "Plexus Archiver", "Build-Id" : "", "Build-Tag" : "", "Built-By" : "cporter"}
$ jq 'keys_unsorted' file.json
[
"Created-By",
"Build-Number",
"Archiver-Version",
"Build-Id",
"Build-Tag",
"Built-By"
]
$ jq 'keys' file.json
[
"Archiver-Version",
"Build-Id",
"Build-Number",
"Build-Tag",
"Built-By",
"Created-By"
]
To get the keys on a deeper node in a JSON:
echo '{"data": "1", "user": { "name": 2, "phone": 3 } }' | jq '.user | keys[]'
"name"
"phone"
You need to use jq 'keys[]'. For example:
echo '{"example1" : 1, "example2" : 2, "example3" : 3}' | jq 'keys[]'
Will output a line separated list:
"example1"
"example2"
"example3"
In combination with the above answer, you want to ask jq for raw output, so your last filter should be eg.:
cat input.json | jq -r 'keys'
From jq help:
-r output raw strings, not JSON texts;
To print keys on one line as csv:
echo '{"b":"2","a":"1"}' | jq -r 'keys | [ .[] | tostring ] | #csv'
Output:
"a","b"
For csv completeness ... to print values on one line as csv:
echo '{"b":"2","a":"1"}' | jq -rS . | jq -r '. | [ .[] | tostring ] | #csv'
Output:
"1","2"
If your input is an array of objects,
[
{
"a01" : { "name" : "A", "user" : "B" }
},
{
"a02" : { "name" : "C", "user" : "D" }
}
]
try with:
jq '.[] | keys[]'
Oddly enough, the accepted answer doesn’t actually answer the Q exactly, so for reference, here is a solution that does:
$ jq -r 'keys_unsorted[]' file.json
echo '{"ab": 1, "cd": 2}' | jq -r 'keys[]' prints all keys one key per line without quotes.
ab
cd
Here's another way of getting a Bash array with the example JSON given by #anubhava in his answer:
arr=($(jq --raw-output 'keys_unsorted | #sh' file.json))
echo ${arr[0]} # 'Archiver-Version'
echo ${arr[1]} # 'Build-Id'
echo ${arr[2]} # 'Build-Jdk'