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
Related
I'm trying to replace objects in a complex JSON object. It seemed that the tool jq could be offering the perfect solution, but I'm really struggling with the right choice / chain of filters.
I have a complete configuration JSON object which looks like this (has some more keys in it, shortened it for illustration):
{
"some-array": [
{
"name": "foo",
"attr": "value"
},
{
"name": "foo bar",
"attr": "value"
},
{
"name": "foo bar baz",
"attr": "value"
}
],
"some-other-array": []
}
Now I have another object containing an array with updated objects which I need to merge with the full configuration in some way. I need to find the nested objects by name, add it if it does not exist yet and replace it if it does exist.
{
"some-array": [
{
"name": "foo",
"attr": "new-value",
"new-attrib": "new-value"
},
{
"name": "foo bar",
"attr": "new-value"
}
]
}
So, with the above example, my expected result would be:
{
"some-array": [
{
"name": "foo",
"attr": "new-value",
"new-attrib": "new-value"
},
{
"name": "foo bar",
"attr": "new-value"
},
{
"name": "foo bar baz",
"attr": "value"
}
],
"some-other-array": []
}
I already tried select(."some-array"[].name == "foo") to begin with and a few other things as a jq filter, but I'm struggling to move forward here and would really appreciate some inspiration / an actual solution.
Can anyone tell me if what I'm trying to achieve is actually possible with jq or do I have to find another solution?
Here is a solution to the updated problem. This solution assumes that the names are string-valued. It relies on two helper functions:
# array-to-hash
def a2h(f): reduce .[] as $x ({}; . + {($x | f): $x});
# hash-to-array
def h2a: . as $in | reduce keys_unsorted[] as $k ([]; . + [$in[$k]]);
The first of these creates a "hash" based on an input array, and the second implements the inverse operation.
With these helper functions, the solution can be written:
.["some-array"] |= (a2h(.name) + ($update|.["some-array"] | a2h(.name)) | h2a)
where $update is the "new" value. This solution relies on the "right-dominance" of object-addition.
Output
For the given example, the output is:
{
"some-array": [
{
"name": "foo",
"attr": "new-value",
"new-attrib": "new-value"
},
{
"name": "foo bar",
"attr": "new-value"
},
{
"name": "foo bar baz",
"attr": "value"
}
],
"some-other-array": []
}
Yes, it's possible, and in fact quite easy under various interpretations of the problem as originally stated.
The following solves the the problem as it was originally stated, with "it" being interpreted as .["some-array"] rather than its constituents.
Assuming $update holds the object with the updated information as shown, the update could be performed using this filter:
.["some-array"] = ($update | .["some-array"])
There are many ways to endow $update with the desired value.
I have some JSON output I am trying to parse with jq. I read some examples on filtering but I don't really understand it and my output it more complicated than the examples. I have no idea where to even begin beyond jq '.[]' as I don't understand the syntax of jq beyond that and the hierarchy and terminology are challenging as well. My JSON output is below. I want to return the value for Valid where the ItemName equals Item_2. How can I do this?
"1"
[
{
"GroupId": "1569",
"Title": "My_title",
"Logo": "logo.jpg",
"Tags": [
"tag1",
"tag2",
"tag3"
],
"Owner": [
{
"Name": "John Doe",
"Id": "53335"
}
],
"ItemId": "209766",
"Item": [
{
"Id": 47744,
"ItemName": "Item_1",
"Valid": false
},
{
"Id": 47872,
"ItemName": "Item_2",
"Valid": true
},
{
"Id": 47872,
"ItemName": "Item_3",
"Valid": false
}
]
}
]
"Browse"
"8fj9438jgge9hdfv0jj0en34ijnd9nnf"
"v9er84n9ogjuwheofn9gerinneorheoj"
Except for the initial and trailing JSON scalars, you'd simply write:
.[] | .Item[] | select( .ItemName == "Item_2" ) | .Valid
In your particular case, to ensure the top-level JSON scalars are ignored, you could prefix the above with:
arrays |
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.)
Example JSON file:
{
"u": "stuff",
"x": [1,2,3],
"y": {
"field": "value"
},
"z": {
"zz": {
"name": "change me",
"more": "stuff"
},
"randomKey": {
"name": "change me",
"random": "more stuff"
}
}
}
How can I update all the name fields to "something", maintaining the rest of the JSON file the same?
{
"u": "stuff",
"x": [1,2,3],
"y": {
"field": "value"
},
"z": {
"zz": {
"name": "something",
"more": "stuff"
},
"randomKey": {
"name": "something",
"random": "more stuff"
}
}
}
With a direct path, this would be easy, but the parent keys (z and randomKey in these case) varies.
I tried something like:
jq '.z | .. | .name? |= "something"' file.json
And it's updating the names, but putting also all the recursive stuff..
If it is acceptable to change the "name" field wherever it occurs, you could use walk/1:
walk(if type == "object" and has("name") then .name = "something" else . end)
Please note that walk/1 was only included with jq after jq 1.5 was released. If your jq does not have it, then you can find its definition on the jq FAQ, for example.
If you only want to modify the "name" field in the "z" context, then consider:
.z |= with_entries(if .value.name?
then .value.name = "something"
else . end)
Assuming every value within z has a name property, you could do this:
$ jq --arg newname 'something' '.z[].name = $newname' input.json
Using [] on an object will yield all the values contained in that object. And for each of those values, we were simply setting the name to the new name.
If you needed to be more selective with what gets updated, you'll have to add more conditions to what objects to update. In general, I'd use peak's approach, but here's another way it could be achieved using a structure similar to the first approach, assuming we only want to update objects that already have a name property:
$ jq --arg newname 'something' '(.z[] | select(has("name")).name) = $newname' input.json
It's important to wrap the LHS of the assignment in parentheses, we don't want to change the context prior to the assignment, otherwise we won't see the rest of the results.
I have a JSON formatted stream, full of objects. Each object looks like this:
{
"object": "alpha",
"attributes": [
{
"type": "A",
"description": "a",
"value": 1271129046.9144535
},
{
"type": "B",
"description": "b",
"value": 6738889338.63777
},
{
"type": "C",
"description": "c",
"value": 214918692.38456276
},
{
"type": "D",
"description": "d",
"value": 140222346.75136077
},
{
"type": "E",
"description": "e",
"value": 2085635554.8128803
}
]
}
I'd like to get data out as:
alpha,A,a,1271129046.9144535
alpha,B,b,6738889338.63777
alpha,C,c,214918692.38456276
alpha,D,d,140222346.75136077
alpha,E,e,2085635554.8128803
The next object may be "beta" instead of "alpha", hence I don't want to just strip the "object" key.
My restrictions are that I want to process this stream in a bash pipeline. I'm hoping I can just use "jq" for this, rather than piping through python/ruby/perl etc which I'd rather not depend on if I can help it.
Any ideas would be most grateful!
It looks like you're building up CSV data, the #csv filter was made for this. You just need to collect an array of the values you want to write out and pass it in to the filter. You could do this:
$ jq -r '.attributes[] as $attr | [.object, $attr.type, $attr.description, $attr.value] | #csv' input.json
Which produces this:
"alpha","A","a",1271129046.9144535
"alpha","B","b",6738889338.63777
"alpha","C","c",214918692.38456276
"alpha","D","d",140222346.75136077
"alpha","E","e",2085635554.8128803
(1) Slightly briefer than the accepted answer:
jq -r '[.object] + (.attributes[] | [.type, .description, .value]) | #csv'
(2) If you don't want the quotation marks, then one possibility would be:
jq -r '"\(.object)," + (.attributes[] | "\(.type),\(.description),\(.value)")'