How to split documents from one file by --- into an array?

[shi-ron]

Hi, if we have data.yml like:

A: 1
B: 2
---
C: 3
D: 4

and we wish to run a command like:

readarray DATA < <(yq -s '---' data.yml)

The array $DATA shall has two elements.

echo "${DATA[0]}"

should be

A: 1
B: 2

and

echo "${DATA[1]}"

should be

C: 3
D: 4

How can I do this? Thank you for your help!

[mikefarah]

I don't know how readarray works - but to get all the documents into a single yaml array you can do this:

yq ea '[.]' data.yaml

- A: 1
  B: 2
- C: 3
  D: 4

[mikefarah]

Forgot to explain:

• ea is shorthand for eval-all which means all the yaml documents are read into memory before running the expression. By default, the expression is run against a single document at a time.
• [.] puts everything in the current context . into an array. Which in in this case, will put all the documents.

[shi-ron]

I see the ea has merged the documents. But I want to iterate them in a loop.

[mikefarah]

Now that it's in an array - you can follow the solution here: https://stackoverflow.com/questions/62898925/using-yq-in-for-loop-bash/70162342#70162342

[shi-ron]

Ok, it works! Thank you.