treebuilder 0.4

Build tree data model.

Tree builder

It's a python package which helps you to build a tree data model to generate configuration files like XML or JSON for example. It provides a xpath syntax like to apply values recursively on your building tree.

Prerequisites

• python 3.6 or higher

Installation

pip install treebuilder

Examples

Build a book store tree

We create a book store with 2 books and 2 copies of each. We also setup the lang as an attribute and a price for each of them.

import treebuilder as tb

builder = tb.TreeBuilder()

# Create 2 books in a bookstore
builder.expand('/bookstore/book/title', ['Sapiens', 'Harry Potter'])

# Set the lang to all books as attribute
builder.set('/bookstore/book/@lang', 'en')

# Set the price for each book
builder.nest('/bookstore/book/price', [39.95, 29.99])

# Duplicate each book to make 2 copies
builder.cross('/bookstore/book/copy_number', [1, 2]) 

builder.to_xml('bookstore.xml')

The output stored into bookstore.xml file looks like:

<bookstore>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>1</copy_number>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>1</copy_number>
  </book>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>2</copy_number>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>2</copy_number>
  </book>
</bookstore>

The next parts of this example suppose that you call builder.to_xml('bookstore.xml') to generate the output after each modification.

Set values with filter

We want now add the author for each book. Each book has its own author so we need to select a sub tree to apply the author.

builder.set('/bookstore/book[title=\'Harry Potter\']/author', 'J K. Rowling')
builder.set('/bookstore/book[title=Sapiens]/author', 'Y N. Harari')

Output

<bookstore>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>1</copy_number>
    <author>Y N. Harari</author>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>1</copy_number>
    <author>J K. Rowling</author>
  </book>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>2</copy_number>
    <author>Y N. Harari</author>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>2</copy_number>
    <author>J K. Rowling</author>
  </book>
</bookstore>

Set values in distinct sub trees

We want add a details section for a book where we will store addtional informations like the publish year.

builder.set('/bookstore/book[title=\'Harry Potter\']/details/published_year', '2005')
builder.set('/bookstore/book[title=Sapiens]/details/published_year', '2014')

Output

<bookstore>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>1</copy_number>
    <author>Y N. Harari</author>
    <details>
      <published_year>2014</published_year>
    </details>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>1</copy_number>
    <author>J K. Rowling</author>
    <details>
      <published_year>2005</published_year>
    </details>
  </book>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>2</copy_number>
    <author>Y N. Harari</author>
    <details>
      <published_year>2014</published_year>
    </details>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>2</copy_number>
    <author>J K. Rowling</author>
    <details>
      <published_year>2005</published_year>
    </details>
  </book>
</bookstore>

Expand values for distinct sub tree

Now we want to set the list of calient which has borrowed books Let's that there is 5 people which borrow Spaiens and 3 Harry Potter

builder.expand('/bookstore/book[title="Harry Potter"]/borrowers/borrower/name', [f'Client_{i+1}' for i in range(3)])
builder.expand('/bookstore/book[title=Sapiens]/borrowers/borrower/name', [f'Client_{i+1}' for i in range(5)])

Output

<bookstore>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>1</copy_number>
    <author>Y N. Harari</author>
    <details>
      <published_year>2014</published_year>
    </details>
    <borrowers>
      <borrower><name>Client_1</name></borrower>
      <borrower><name>Client_3</name></borrower>
      <borrower><name>Client_5</name></borrower>
    </borrowers>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>1</copy_number>
    <author>J K. Rowling</author>
    <details>
      <published_year>2005</published_year>
    </details>
    <borrowers>
      <borrower><name>Client_1</name></borrower>
      <borrower><name>Client_3</name></borrower>
    </borrowers>
  </book>
  <book lang="en">
    <title>Sapiens</title>
    <price>39.95</price>
    <copy_number>2</copy_number>
    <author>Y N. Harari</author>
    <details>
      <published_year>2014</published_year>
    </details>
    <borrowers>
      <borrower><name>Client_2</name></borrower>
      <borrower><name>Client_4</name></borrower>
    </borrowers>
  </book>
  <book lang="en">
    <title>Harry Potter</title>
    <price>29.99</price>
    <copy_number>2</copy_number>
    <author>J K. Rowling</author>
    <details>
      <published_year>2005</published_year>
    </details>
    <borrowers>
      <borrower><name>Client_2</name></borrower>
    </borrowers>
  </book>
</bookstore>

...

Contributing

Issue tracker: https://github.com/fdieulle/treebuilder/issues

If you want to checkout the project and propose your own contribution, you will need to setup the project with the following steps:

Create a virtual environment:

python -m venv venv

Activate your virtual environment:

venv/Scripts/activate

Install package dependencies

pip install -r requirements.txt

License

This project is open source under the MIT license.