DotChain - Python method chaining and piping with asyncio support.

Install

pip install dotchain

Usage

Chain Synchronously

Call .Result() to get the value.

value = DotChain(data | iterable).method().property.Result()

Chain Asynchronously

Do not call .Result() when using await.

value = await DotChain(data | iterable).method().property

NOTE: Must be in an event loop to use await.

Piping

Pipe can be called anywhere in the chain to start piping the data.

Chain can be called anywhere in the chain to start chaining the data again.

# Piping
value = DotChain(data | iterable).Pipe.method().other_method().Result()

# Chaining and Piping
value = DotChain(data | iterable).method().property.Pipe.other_method().Chain.property.Result()

Contexts

Contexts can be provided to resolve methods and properties so they can be used inline.

With can be called anywhere in the chain to add or clear contexts.

import utils  # contains `log(...)`

value = DotChain(data | iterable).With(utils).method().log().Result()

value = DotChain(data | iterable).With({'utils': utils}).method().utils.log().Result()

value = DotChain(data | iterable).With(self).method().utils.log().Result()

Call inline functions

value = DotChain(data | iterable).method().Call(lambda item: item.property).Result()

Examples

from dotchain import DotChain
import log_utils

# Chaining
order = DotChain(user).get_order('123').cancel().Result()

# Chaining with Piping
email_result = DotChain(user).get_order('123').cancel().Pipe.send_email().Result()

# With lookup contexts
order = DotChain(user).With(log_utils).get_order('123').cancel().Pipe.log_cancel().Result()

order = DotChain(user).With({'log_it': lambda order: log_utils.log_cancel(order)}).Pipe.log_it().Result()

# Inline callables
order = DotChain(user).get_order('123').cancel().Pipe.Call(lambda order: log_utils.log_cancel(order)).Result()

See Tests for more examples and usage.