Using jq, how can I transform an input to a JSON object which maps the first level keys to the value of the latest nested value? For example, given the input
{
"foo": {
"current": "0.15.14",
"wanted": "0.15.14",
"latest": "0.16.4",
},
"bar": {
"current": "8.27.0",
"wanted": "8.27.0",
"latest": "8.29.0",
},
"baz": {
"current": "27.1.5",
"wanted": "27.1.5",
"latest": "27.1.6",
}
}
How can it be transformed to
{
"foo": "0.16.4",
"bar": "8.29.0",
"baz": "27.1.6"
}
Map all field values to their .latest field, either by using map_values
map_values(.latest)
Demo
Or by updating |= each field .[] with that filter
.[] |= .latest
Demo
Actually, map_values(f) is just a defined shortcut for .[] |= f.
Related
I would like to aggregate two or more files into a single json, and aggregate arrays under a same key.
file1.json
{
"shapes": [
{
"id": "1",
"name": "circle"
},
{
"id": "2",
"name": "square"
}
]
}
file2.json
{
"shapes": [
{
"id": "3",
"name": "triangle"
}
]
}
Expected result :
{
"shapes": [
{
"id": "1",
"name": "circle"
},
{
"id": "2",
"name": "square"
},
{
"id": "3",
"name": "triangle"
}
]
}
I can do this with the following jq command :
jq -s '{shapes: map(.shapes)|add }' file*.json
But this requires me to know the shapes attribute and hardcode it. Is there a simple way I can get the same result without ever using the key name explicitly?
Here is a solution that’s suitable when each top-level object has only one key, and that is both efficient and conceptually simple. It assumes jq is invoked with the -n option.
reduce inputs as $in (null;
($in|keys_unsorted[0]) as $k | { ($k): (.[$k] + $in[$k]) })
or slightly more compactly:
reduce inputs as $in (null; ($in|keys_unsorted[0]) as $k | .[$k] += $in[$k] )
Here is a solution that also solves a more general problem: first, it handles arbitrarily many input files; and second, it forms the "sum" by key, for every key, on the assumption that every top-level key is array-valued.
The generic function:
# the values at each key are assumed to be arrays
def aggregate(stream):
reduce stream as $o ({};
reduce ($o|keys_unsorted[]) as $k (.;
.[$k] += $o[$k] ));
To avoid "slurping", we will use inputs:
aggregate(inputs)
The invocation must therefore use the -n command-line option:
jq -n -f program.jq *.json
Try the following code. This can handle any number of files. All inputs are assumed to be json objects with all values inside as arrays. All such arrays are aggregated after grouping by keys. It outputs an object which has keys associated with corresponding aggregated arrays.
jq -s 'map(to_entries)|add|group_by(.key)|
map( { "key": (.[0].key), "value": (map(.value)|add)})|
from_entries' file1.json file2.json
For your sample input this gives:
{
"shapes": [
{
"id": "1",
"name": "circle"
},
{
"id": "2",
"name": "square"
},
{
"id": "3",
"name": "triangle"
}
]
}
All the demo/examples I saw are filtering on the first level, but I want to do the array filtering with jq on the second level:
{
"TheArray": [
{
"F1": "V11",
"F2": "V12",
"F3": "V13"
},
{
"F1": "V21",
"F2": "V22",
"F3": "V33"
} ]
}
I want to filter with "F1" == "V11", and get:
{
"TheArray": [
{
"F1": "V11",
"F2": "V12",
"F3": "V13"
} ]
}
Is that possible with jq?
You can use this jq filter:
jq '.TheArray |= map(select(.F1=="V11"))' file
select command choose the right element and map is building the array based on the selected elements.
The following would be suitable if you want a solution that simply "edits" the original document, retaining any other keys that the top-level object might have:
.TheArray |= map(select(.F1=="V11"))
Variations
with_entries( .value |= map(select(.F1 == "V11")))
Another:
del(.TheArray[] | select(.F1!="V11"))
And if you have a more recent version of jq than version 1.5:
.TheArray[] |= select(.F1=="V11")
In my JSON document I have a string that I need manipulated and then have the entire document returned with the 'fixed' values.
The input document is:
{
"records" : [
{
"time": "123456789000"
},
{
"time": "123456789000"
}
]
}
I want to find the "time" key and replace the string by dropping off the last 3 chars. The resulting document would be:
{
"records" : [
{
"time": "123456789"
},
{
"time": "123456789"
}
]
}
I've been trying to understand the jq query syntax but I'm not coming right. I'm still struggling to return the whole document when filtering on a specific value. All I have so far is:
.records[] | select(.time | contains("123456789000"))
Here is a solution using |= and string slicing
.records[].time |= .[:-3]
Sample Run (assuming data in data.json)
$ jq -M '.records[].time |= .[:-3]' data.json
{
"records": [
{
"time": "123456789"
},
{
"time": "123456789"
}
]
}
Try it online at jqplay.org
With jq sub() function:
jq '.records[].time |= sub("[0-9]{3}$";"")' file
The output:
{
"records": [
{
"time": "123456789"
},
{
"time": "123456789"
}
]
}
Or even simpler: via dividing the time value by 1000:
jq '.records[].time |= (tonumber / 1000 | tostring)' file
The following works with jq version 1.4 or later:
jq '.records[].time |= .[:-3]' file.json
(The expression .[:-3] is short for .[0:-3]; the negative integer here counts from the right.)
With jq 1.3, the following filter would work in your particular case:
.records[].time |= (tonumber | ./1000 | tostring)
I have a list of objects and want to replace all occurrences of . with : when the key is Name using jq
input:
{
"Parameters": [
{
"Name": "TEST.AB.SOMETHING",
"Value": "hvfuycsgvfiwbiwbibibewfiwbcfwifcbwibcibc"
},
{
"Name": "TEST_GF_USER",
"Value": "ssssecret"
}
]
}
expected output:
{
"Parameters": [
{
"Name": "TEST:AB:SOMETHING",
"Value": "hvfuycsgvfiwbiwbibibewfiwbcfwifcbwibcibc"
},
{
"Name": "TEST_GF_USER",
"Value": "ssssecret"
}
]
}
You may split by . and join by :
jq '(.Parameters[].Name)|=(split(".")|join(":"))' file.json
The assignment is done using the update operator.
The trick is to use .Name |= gsub("\\.";":"). In your case (a flat list), it's simple. If you want to modify the keys of all objects in an arbitrary JSON text, the simplest would be to use walk/1:
walk( if type == "object" and has("Name") then .Name |= gsub("\\.";":")) else . end )
(If your jq does not have walk/1, then its jq definition can readily be found by googling.)
I want to update a value in a dict, which I can only identify by another value in the dict. That is, given this input:
[
{
"format": "geojson",
"id": "foo"
},
{
"format": "geojson",
"id": "bar"
},
{
"format": "zip",
"id": "baz"
}
]
I want to change baz's accompanying format to 'csv':
[
{
"format": "geojson",
"id": "foo"
},
{
"format": "geojson",
"id": "bar"
},
{
"format": "csv",
"id": "baz"
}
]
I have found that this works:
jq 'map(if .id=="baz" then .format="csv" else . end)' my.json
But this seems rather verbose, so I wonder if there is a more elegant way to express this. jq seems to be missing some kind of expression selector, the equivalent of might be [#id='baz'] in xpath.
(When I started this question, I had [.[] |...], then I discovered map, so it's not quite as bad as I thought.)
A complex assignment is what you're looking for:
jq '(.[] | select(.id == "baz") | .format) |= "csv"' my.json
Perhaps not shorter but it is more elegant, as requested. See the last section of the docs at: http://stedolan.github.io/jq/manual/#Assignment
Edit: using map:
jq 'map((select(.id == "baz") | .format) |= "csv")' my.json