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Version: 0.7



The KCL Validation tool supports basic configuration data verification capabilities. You can write a KCL schema to verify the type and value of the input JSON/YAML files.

How to use

There is a JSON format file data.json:

"name": "Alice",
"age": 18,
"message": "This is Alice",
"data": {
"id": 1,
"value": "value1"
"labels": {
"key": "value"
"hc": [1, 2, 3]

Build a validated KCL file schema.k:

schema User:
name: str
age: int
message?: str
data: Data
labels: {str:}
hc: [int]

age > 10

schema Data:
id: int
value: str

Execute the following command:

kcl vet data.json schema.k

Specify the schema for validation

When multiple schema definitions exist in the KCL file, by default, the KCL Validation tool will use the first schema to check. If you need to specify a schema for verification, you can use the -s|--schema parameter

kcl vet data.json schema.k -s User


This command validates the data file using the kcl code.

kcl vet [flags]

# Validate the JSON data using the kcl code
kcl vet data.json code.k

-a, --attribute_name string Specify the validate config attribute name.
--format string Specify the validate data format. e.g., yaml, json. Default is json
-h, --help help for vet
-s, --schema string Specify the validate schema.