Fava Classy Portfolio Extension

Warning: Prototype Code

This is a prototype I'm throwing out there due to interest from the Beancount Community (see https://groups.google.com/forum/#!msg/beancount/XNjjnML_vsA/e_MAEhgCBgAJ ). Issues / PR's welcome! So far this is just an early prototype to get a table breakdown view done, there's still work to be done on numeric features (e.g. gain/loss, tax, etc.).

Introduction

Classy Portfolio is an Extension for Fava, a web interface for the Beancount plaintext accounting software. The extension displays a list of different portfolios (e.g. 'taxable' vs. 'retirement'), with breakdowns using 'asset-class' and 'asset-subclass' metadata labels on commodities.

It's recommended (though not required) to use this extension along with the beancount metadata spray plugin to ease with tagging multiple accounts with portfolio metadata.

An example file is available at https://github.com/seltzered/fava-classy-portfolio-demo.

Compatibility with Fava

This currently works with fava 1.19. Since this extension depends on internal fava API's compatibility may change.

Usage

1. Clone this repo into the same directory as your beancount ledger.

2. In your ledger file, add asset-class and asset-subclass metadata strings to commodity entries. Should look similar to:

   2010-01-01 commodity VTI
     name: "Vanguard Total Market Index ETF"
     asset-class: "Stock"
     asset-subclass: "US-Total Domestic Market"
     price: "USD:yahoo/VTI" 

3. In your ledger file, add portfolio metadata strings to account entries. Should look similar to:

   2010-01-01 open Assets:Vanguard:RothIRA:VTI
       portfolio: "retirement"

   ...or if you're using the metadata spray plugin:

   2010-01-01 open Assets:Vanguard:RothIRA:VTI
   plugin "beancount_plugins_metadata_spray.plugins.metadata_spray" "{
   'sprays': [{ 'spray_type': 'account_open',
                 'replace_type': 'return_error',
                 'pattern': 'Assets:Vanguard:RothIRA:.*',
                 'metadata_dict': {'portfolio': 'retirement'}
                 }]
   }"

4. In your ledger file, instantiate the extension with a line similar to:

   2010-01-01 custom "fava-extension" "fava_classy_portfolio" "[
           ('account_open_metadata_pattern', ('portfolio', 'retirement'))
   ]"

5. Because this is an early prototype, you will need to clone/run fava from latest source. See first section "PROTOTYPE: modification to fava required" in this document on modifying fava.

6. Run fava on the ledger file. A link in the sidebar should appear.

References

This extension was somewhat inspired by the Beancount Portfolio Allocation plugin, which I believe follows similar conventions on metadata labeling.