使用 jq 根据输入中其他地方的值从数组中删除项目

Question

I'm new to jq and trying to wrap my head around doing a few things that I thought were going to be straightforward. Any ideas on how to improve this would be greatly appreciated.

Given this input:

{
    "source": {
        "items": [
            { "id": "aaa", "name": "this" },
            { "id": "bbb", "name": "that" },
            { "id": "ccc", "name": "the other" }
        ]
    },
    "update": {
        "toRemove": [
            "aaa",
            "ccc"
        ]
    }
}

I want this result:

{
    "items": [
        { "id": "bbb", "name": "that" }
    ]
}

This filter does the job but the variables lead me to believe there is a cleaner way.

. as $root | .source + { items: [.source.items[] | select(.id as $id | $root.update.toRemove | contains([$id]) | not)]}

Playground link if interested: https://jqplay.org/s/GpVJfbTO-Q

Answer 1

Here's a concise and efficient solution:

.update.toRemove as $rm
| .source
| .items |= map( select(.id | IN($rm[]) | not))

Answer 2

A little shorter version using inside instead of contains :

.update.toRemove as $temp |
 {items: [.source.items[] | select([.id] | inside($temp) | not)]}

Answer 3

and an alternative solution, using jtc

bash $ <input.json jtc -w'<items>l[-1]' | jtc -w'[id]:<bbb>[-1]' -pp
{
   "items": [
      {
         "id": "bbb",
         "name": "that"
      }
   ]
}
bash $ 

first jtc statement prints items entirely, second removes everything except object with bbb

* UPDATE * latest version of jtc allows now namespaces. To facilitate the ask, use it like this:

bash $ <input.json jtc -w'[update][toRemove][:]<2rm>v [^0][id]:<2rm>s[-1]' -p | jtc -w'[source]'
{
   "items": [
      {
         "id": "bbb",
         "name": "that"
      }
   ]
}
bash $ 

Explanations:

1. [update][toRemove][:]<2rm>v - that portion of a walk-path will iterate over each item in toRemove while storing each iterated value in the namespace 2rm

2. [^0][id]:<2rm>s[-1] - will reset the walk-path back to root ( [^0] ) and find each JSON entry matching one stored in 2rm , [-1] will select a parent of the found entry (which selects the item record

3. -p will purge the found (walked) elements and next jtc will select the source