Maintain order of jq CSV output and include empty values - json

Question

I am currently working on a bash script that combines the output of both the aws iam list-users and aws iam list-user-tags commands in a CSV file containing all users along with their respective information and assigned tags. To parse the JSON output of those commands I choose to use jq.
Retrieving parsing and converting (JSON to CSV) the list-user output works fine and produces the expected comma-separated list of values.
The output of list-user-tags does not quite behave that way. Its JSON output has the following schema:
{
Tags: [
{
Key: "Name",
Value: "NameOfUser"
},
{
Key: "Email",
Value: "EmailOfUser"
},
{
Key: "Company",
Value: "CompanyOfUser"
}
]
}
Unfortunately the order of the tags is not consistent across users (and possibly across queries) which currently makes it impossible for me to maintain the order defined in the CSV file. On top of that there is the possibility of one or multiple missing tags.
What I am looking for is a way to achieve the following (preferably using jq):
Select a tags "Value"-value by its "Key"-value
Check whether it is existent and if not add an empty entry
Put the value in the exact same place every time (maintain a certain order)
Repeat for every entry in the original output
Convert the resulting array of values into CSV
What I tried so far:
aws iam list-user-tags --user-name abcdef --no-cli-pager \
| jq -r '[.Tags[] | select(.Key=="Name"),select(.Key=="Email"),select(.Key=="Company") | .Value // ""] | #csv'
Any help is much appreciated!

Answer 1

Let's suppose your sample "schema" is in a file named schema.jq
Then
jq -n -f schema.jq | jq -r '
def get($key):
map(select(.Key == $key))
| if length == 0 then null else .[0].Value end;
.Tags | [get("Name"), get("Email"), get("Company")] | #csv
'
produces the following CSV:
"NameOfUser","EmailOfUser","CompanyOfUser"
It should be easy to adapt this illustration to your needs.