brandon/oam
1
0
Fork 0
mirror of https://gitea.com/mcereda/oam.git synced 2026-02-09 13:44:24 +00:00
Code Issues Packages Projects Releases Wiki Activity

Improved JQ's examples

Browse Source
This commit is contained in:
Michele Cereda
2022-07-12 10:52:06 +02:00
parent 30c53f718c
commit 2f241ecc8a
1 changed files with 46 additions and 19 deletions
Download Patch File Download Diff File Expand all files Collapse all files

65
knowledge base/jq.md
View File

@@ -3,41 +3,66 @@
## TL;DR
```sh
# add a field
# Add a key.
jq --arg REGION ${AWS_REGION} '.spec.template.spec.containers[]?.env? += [{name: "AWS_REGION", value: $REGION}]' /tmp/service.kube.json
# delete a field
# Delete a key.
jq 'del(.items[].spec.clusterIP)' /tmp/service.kube.json
# update a field
# Change a value.
jq '.extensionsGallery
| .serviceUrl |= "https://marketplace.visualstudio.com/_apis/public/gallery"' \
/usr/lib/code/product.json
jq --arg NAMESPACE ${NAMESPACE} '.spec.template.spec.containers[]?.env[]? |= {name: .name, value: (if .name == "KUBERNETES_NAMESPACE" then $NAMESPACE else .value end)}' /tmp/service.kube.json
# sort keys
# Change multiple values at once.
jq '.extensionsGallery
| .serviceUrl = "https://marketplace.visualstudio.com/_apis/public/gallery"
| .cacheUrl = "https://vscode.blob.core.windows.net/gallery/index"
| .itemUrl = "https://marketplace.visualstudio.com/items"' \
/usr/lib/code/product.json
jq '.extensionsGallery + {
serviceUrl: "https://marketplace.visualstudio.com/_apis/public/gallery",
cacheUrl: "https://vscode.blob.core.windows.net/gallery/index",
itemUrl: "https://marketplace.visualstudio.com/items"
}' /usr/lib/code/product.json
# Sort all the keys.
jq --sort-keys '.' input.json > output.json
# put specific keys on top
# Put specific keys on top.
jq '.objects = [(.objects[] as $in | {type,name,id} + $in)]' prod/dataPipeline_deviceLocationConversion_prod.json
# convert enpass' json export to yaml file
# Convert Enpass' JSON export to a YAML file
jq '.items[] | {title, fields} | .title + ":", (.fields[] | select(.value != "") | " " + .label + ": " + .value)' test.json -cr
# datapipeline definition refactor
for definition_file in $(find prod -type f -name "*.json")
do
jq --sort-keys '.' ${definition_file} > /tmp/sorted.json
jq '.objects = [(.objects[] as $in | {type,name,id} + $in | with_entries(select(.value != null)))]' /tmp/sorted.json > /tmp/reordered.json
mv /tmp/reordered.json ${definition_file}
done
# Refactor a datapipeline definition.
jq --sort-keys '.' datapipeline.json > /tmp/sorted.json \
&& jq '.objects = [(.objects[] as $in | {type,name,id} + $in | with_entries(select(.value != null)))]' \
/tmp/sorted.json > /tmp/reordered.json \
&& mv /tmp/reordered.json datapipeline.json
# extract data from elements with specific keys
kubectl get pods -o yaml | yq -y '.items[] | select(.metadata.name | test("^runner-.*")) | select(.spec.tolerations[].key == "component" and .spec.tolerations[].value == "big-runner") | .spec.nodeSelector, .spec.tolerations' -
# Extract the value of elements with specific keys.
kubectl get pods -o yaml \
| yq -y '
.items[]
| select(.metadata.name | test("^runner-.*"))
| select(.spec.tolerations[].key == "component" and .spec.tolerations[].value == "big-runner")
| .spec.nodeSelector, .spec.tolerations' \
-
# recursively find all the properties whose key is 'errors' whether it exists or not
# '..' unrolls the object, '?' checks for the value or returns null, and 'select(.)' is like a filter on truthy values
# Recursively find all the properties whose key is 'errors' whether it exists or not.
# '..' unrolls the object, '?' checks for the value or returns null, and 'select(.)' is like a filter on truthy values.
jq '[.. | .errors?[0] | select(.) ]' /tmp/helm.template.out.json
# find all images in a helm chart explicitly or implicitly using the tag 'latest'
helm template ${CHART} | yq -r '.. | .image? | select(.) | select(.|test(".*:.*")|not), select(.|test(".*:$")), select(.|test(".*:latest"))' -
# Find all images in a helm chart explicitly or implicitly using the tag 'latest'.
helm template chartName \
| yq -r '
..
| .image?
| select(.)
| select(.|test(".*:.*")|not), select(.|test(".*:$")), select(.|test(".*:latest"))' \
-
```
## Further readings
@@ -50,6 +75,8 @@ helm template ${CHART} | yq -r '.. | .image? | select(.) | select(.|test(".*:.*"
- [Filter objects list with regex]
- [Select multiple conditions]
- [Change multiple values at once]
[change multiple values at once]: https://stackoverflow.com/questions/47355901/jq-change-multiple-values#47357956
[filter objects list with regex]: https://til.hashrocket.com/posts/uv0bjiokwk-use-jq-to-filter-objects-list-with-regex
[select multiple conditions]: https://stackoverflow.com/questions/33057420/jq-select-multiple-conditions#33059058