🧠 What PyDeftLariats Does

• Abstracts PyHamcrest matchers into field-based matchers, allowing structured matching against dictionary-style data records (e.g., rows in a dataset or events in a stream).
• Provides reusable, composable matchers for specific field keys and types: text, numbers, existence, dictionaries, etc.
• Enables rule-style matching logic to be implemented declaratively and extensibly.

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Example Usage

Extract specific records from the Coingecko API using PyDeftLariats.

• assuming you have jq installed

• One Record form the Coingecko API

{
  "name": "Mogo Inc.",
  "symbol": "NASDAQ:MOGO",
  "country": "CA",
  "total_holdings": 18,
  "total_entry_value_usd": 595494,
  "total_current_value_usd": 391423,
  "percentage_of_total_supply": 0
}

• Use jq to extract the record from the Coingecko API and stream to deft
• deft is the command line tool for PyDeftLariats

Goal: return all records that match any of the following criteria:

• symbol is OTCMKTS:FRMO
• total_holdings is greater than or equal to 1000
• percentage_of_total_supply is greater than or equal to 0.1

how that gets created in code... the Python code for example-coingecko fuction is:

    ...
    field_key = 'symbol'
    filter_one = EqualTo(field_key)
    target_value = 'OTCMKTS:FRMO'

    filter_two = NumberComparer('total_holdings', MatcherType.GREATER_THAN_EQUAL_TO)
    filter_three = NumberComparer('percentage_of_total_supply', MatcherType.GREATER_THAN_EQUAL_TO)
    for x in data:
        if any([filter_one.is_match(target_value, x),
                filter_two.is_match(1000, x),
                filter_three.is_match(0.1, x),
                ]):
            click.echo(f"Data Filter hit for record:\n{x}\n\n")

Running from the command line:

curl 'https://api.coingecko.com/api/v3/companies/public_treasury/bitcoin' |  jq '.companies[]' | deft example-coingecko

Comparers:

• EqualTo
• TextComparer
• NumberComparer
• Exists
• Anything
• Nothing

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Random Stuff

Additional Documentation

I am playing with MyST for documentation

Thus, visit https://pydeftlariats.readthedocs.io/ for more information.