XML to YAML
This command takes an XML snippet and converts it into YAML.
Let's say you have an Apigee policy written in XML format. Instead of manually retyping the whole thing into YAML, you can simply use this tool for instant conversion.
This is handy when you're working with examples from the Apigee documentation, just:
- Copy
- Paste
- Convert
Usage
The xml-to-yaml command takes two parameters -input and -output
-
--inputis the XML document to transform -
--outputis the YAML document to be created -
--outputfull path is created if it does not exist (likemkdir -p)
You may omit the
--inputor--outputflags to read or write from stdin or stdout
Examples
Below are a few examples for using the xml-to-yaml command.
From a file
Reading input redirected from a file
From stdin
Reading input directly from stdin
apigee-go-gen transform xml-to-yaml << EOF
<Parent>
<Child>Fizz</Child>
<Child>Buzz</Child>
</Parent>
EOF
From a process
Reading input piped from another process
echo '
<Parent>
<Child>Fizz</Child>
<Child>Buzz</Child>
</Parent>' | apigee-go-gen transform xml-to-yaml
Transform Rules
When converting between XML and YAML the following basic rules are used:
| XML Representation | YAML Representation |
|---|---|
| Element | As Field |
| Attribute | As Field prepended with a dot . |
Element with char-data e.g. <Simple>Value</Simple> |
As Field with Scalar content e.g. Simple: Value |
| Element sequence | Must use Array to hold the children |
| Element with order-sensitive children | Must use Array to hold the children |
| Element with non-order-sensitive children (unique) | Should use map to hold the children |
| Element having attributes and char-data | Must put char-data within a field prepended with - |
| Element having attributes and order-sensitive children | Must put children within a field prepended with - |
This format is similar to Badgerfish style, but it's not as strict.
It makes concessions so that simple XML translates into simple YAML when possible.
The idea is that the YAML should be intuitive to write by just looking at the XML.
There is no name for this format, you can call it apigeek-style
Note
If there is char-data intermingled between XML elements, that is not preserved during transform.
XML to YAML Examples
Below is a list of examples to help illustrate the XML to YAML transformation logic.
The examples start very simple, and get gradually more complex.
1. Simple element
XML element with char data content
is equivalent to2. Add Attributes
XML element with an attribute
is equivalent to3. Content & Attributes
XML element with an attribute and char data content
is equivalent to4. Nested Elements
XML element containing another XML element
is equivalent to5. Named Sequence
XML sequence that has a container element
<Catalog>
<Books>
<Book>The Cat in the Hat</Book>
<Book>Green Eggs and Ham</Book>
</Books>
</Catalog>
6. Unnamed Sequence
XML sequence without container element
is equivalent to7. Sequence & Attrs.
XML sequence without container, but parent has attributes
<Catalog name="Children's Books" language="English">
<Book>The Cat in the Hat</Book>
<Book>Green Eggs and Ham</Book>
</Catalog>
Catalog:
.name: Children's Books
.language: English
-Data:
- Book: The Cat in the Hat
- Book: Green Eggs and Ham
8. Unnamed Seq. & Attrs.
XML sequence without container, but parent has attributes, and children have attributes
<Catalog name="Children's Books" language="English">
<Book author="Dr. Seuss">The Cat in the Hat</Book>
<Book author="Dr. Seuss">Green Eggs and Ham</Book>
</Catalog>
Catalog:
.name: Children's Books
.language: English
-Data:
- Book:
.author: Dr. Seuss
-Data: The Cat in the Hat
- Book:
.author: Dr. Seuss
-Data: Green Eggs and Ham
9. Named Seq. & Attrs.
XML sequence with a container, parent has attributes, and children have attributes
is equivalent to