bash search and replace a line after a certain line - bash

Question

I have a big yaml file containing multiple declaration blocks, related to different services.
The structure is similar to the following (but repeated for multiple applications):
- name: commerce-api
type: helm
version: 0.0.5
I would like to find the block of code that is containing commerce-api and replace the version property value with something else.
The thing is, I wrote this script:
bumpConfig() {
LINE=$(awk "/- name: $1$/{print NR + $2}" "$CONFIG_YML")
sed -i "" -E "${LINE}s/version: $3.*$/\version: $4/" "$CONFIG_YML"
}
bumpConfig "commerce-api" 2 "$OLD_APP_VERSION" "$NEW_APP_VERSION"
Which is kind of allowing me to do what I want, but the only problem is that, the property version is not always on the third line.
How can I make my script to look for the first occurrence of version given the service name to be commerce-api?
Is this even possible using awk?

Answer 1

Adding some variation to the input file:
$ cat config.yml
- name: commerce-api-skip
type: helm
version: 0.0.5
- name: commerce-api
type: helm
bogus line1: bogus value1
version: 0.0.5
bogus line2: bogus value2
- name: commerce-api-skip-too
type: helm
version: 0.0.5
One awk idea:
bumpConfig() {
awk -v name="$1" -v old="$2" -v new="$3" '
/- name: / { replace=0
if ($NF == name)
replace=1
}
replace && $1=="version:" { if ($NF == old)
$0=substr($0,1,index($0,old)-1) new
}
1
' "${CONFIG_YML}"
}
Taking for a test drive:
CONFIG_YML='config.yml'
name='commerce-api'
OLD_APP_VERSION='0.0.5'
NEW_APP_VERSION='0.0.7'
bumpConfig "${name}" "${OLD_APP_VERSION}" "${NEW_APP_VERSION}"
This generates:
- name: commerce-api-skip
type: helm
version: 0.0.5
- name: commerce-api
type: helm
bogus line1: bogus value1
version: 0.0.7
bogus line2: bogus value2
- name: commerce-api-skip-too
type: helm
version: 0.0.5
Once OP is satisfied with the result:
if running GNU awk the file can be updated 'in place' via: awk -i inplace -v name="$1" ...
otherwise the output can be saved to a temp file and then copy the temp file over the original: awk -v name="$1" ... > tmpfile; mv tmpfile "${CONFIG_YML}"

Answer 2

Entirely in sed
sed -i '' "s/^version: $3/version: $4/' "$CONFIG_YML"
/^- name: $1\$/,/^- name:/ restricts the s command to just the lines between the requested name and the next - name: line.

Answer 3

#!/bin/bash
OLD_APP_VERSION=0.0.5
NEW_APP_VERSION=0.0.7
CONFIG_YML=config.yml
bumpConfig() {
gawk -i inplace -v name="$1" -v old="$2" -v new="$3" '
1
/^- name: / && $3 == name {
while (getline > 0) {
if (/^ version: / && $2 == old)
$0 = " version: " new
print
if (!NF || /^-/ || /^ version: /)
break
}
}
' "${CONFIG_YML}"
}
bumpConfig commerce-api "${OLD_APP_VERSION}" "${NEW_APP_VERSION}"