yaml-transformer

A Java library for accomplishing simple transformations in Yaml documents.

Building it

Just checkout the project and generate an uber jar with:

mvn assembly:assembly -DdescriptorId=jar-with-dependencies

The jar will be generated in:

target/yaml-transformer-xxx-jar-with-dependencies.jar

(rename it as you wish)

Executing it

Execute the jar passing the following arguments:

java -jar yaml-transformer.jar <INPUT_FILE> <OUTPUT_FILE> <PROPERTIES_MAP> <OUTPUT_STYLE>

Where:

<PROPERTIES_MAP> is a list of the form [k1->v1|k2->v2|...]. Each key->value pair describes the new value of a property.

<OUTPUT_STYLE> is an optional argument. It can either be AUTO, BLOCK or FLOW. Please see the SnakeYaml documentation for details.

Examples

Considere the following sample file (extracted from the SnakeYaml documentation):

invoice: 34843
date: 2001-01-23T00:00:00Z
billTo: &id001
  given: Chris
  family: Dumars
  address:
    lines: |
      458 Walkman Dr.
      Suite #292
    city: New City
    state: MI
    postal: 48046
shipTo: *id001
product:
- sku: BL394D
  quantity: 4
  description: Basketball
  price: 450.0
- sku: BL4438H
  quantity: 1
  description: Super Hoop
  price: 2392.0
tax: 251.42
total: 4443.52
comments: Late afternoon is best. Backup contact is Nancy Billsmer @ 338-4338.

If you would like to change the name of the city in the billing address you can execute:

java -jar yaml-transformer.jar test.yaml test.out.yaml "root.billTo.address.city->New City"

Note that the output style is optional. If you want to specify it, the following command is also valid:

java -jar yaml-transformer.jar test.yaml test.out.yaml "root.billTo.address.city->New City" BLOCK

In order to execute more than one transformation in the same execution, just surround the list of changes between square brackets and separate each change with the pipe character (|).

The following command changes both the name of the city and the state in the billing address of the previous example:

java -jar yaml-transformer.jar test.yaml test.out.yaml "[root.billTo.address.city->New City|root.billTo.address.state->New State]"

Limitations

• Only simple map properties can be modified in the current version.
• The input must fully respect the Yaml specification.
• The underlying YAML parser employed by YamlTransformer does not keep existing comments.
• The output file may have a different layout than the input file.

License

yaml-transformer is open source, distributed under the terms of this license.