Appending the array of strings to a yaml list

[paradajz]

I have an array stored in bash variable containing data, eg:

line1
line2
line3

Now I want to append those lines to a single subkey, like so:

---
list:
 - line1
 - line2
 - line3

Can't figure out how to do that. The closest I got was this:

#!/bin/bash

filename=test.yaml
echo "---" > $filename
array=(line1 line2 line3)

for ((i=0;i<${#array[*]};i++))
do
    {
        echo "" |
        dasel put string -p yaml "list.[$i]" "${array[$i]}"
    } >> $filename
done

This produces the following:

---
list:
- line1
list:
- line2
list:
- line3

[TomWright]

The dasel command you're looking for is:

$ dasel put string -f test.yaml -o - "list.[]" "line4"
list:
- line1
- line2
- line3
- line4

Note that to append we use the [] selector rather than [$i]. Using [$i] you will be overwriting the value at that index.

$ dasel put string -f test.yaml -o - "list.[1]" "line4"
list:
- line1
- line4
- line3

Here's an example run.sh that will append the bash array items to test.yaml and write the results to test.out.yaml:

#!/bin/bash

filename=test.yaml
out_filename=test.out.yaml

# new items to be added to the list
array=(line4 line5 line6)

# copy filename contents to out_filename.
cp $filename $out_filename

for ((i=0;i<${#array[*]};i++))
do
    {
        dasel put string -f "$out_filename" "list.[]" "${array[$i]}"
    }
done

echo -e "---\n$(cat $out_filename)" > $out_filename

E.g.

$ cat test.yaml
---
list:
 - line1
 - line2
 - line3

$ cat test.out.yaml
---
list:
- line1
- line2
- line3
- line4
- line5
- line6

If you'd rather have the list rewritten then you can update run.sh as you see fit.

[TomWright]

As a side note, your main issue was that you were passing a blank document to dasel for every item within the for loop, rather than using the output from the previous loop.

[paradajz]

Exactly the kind of info I was looking for. Thanks a lot!