RunnableFunction<RunInput extends Object, RunOutput extends Object> class

A RunnableFunction allows you to run a Dart function as part of a chain.

You can create a RunnableFunction using the Runnable.fromFunction static method.

When you call invoke on a RunnableFunction, it will invoke the function, passing the input to it. The output of the function is returned.

Example:

final openaiApiKey = Platform.environment['OPENAI_API_KEY'];
final model = ChatOpenAI(apiKey: openaiApiKey);

final promptTemplate = ChatPromptTemplate.fromTemplate(
  'How much is {a} + {b}?',
);

final chain = Runnable.fromMap({
      'a': Runnable.fromFunction((
        final Map<String, String> input,
        final options,
      ) async {
        final foo = input['foo'] ?? '';
        return '${foo.length}';
      }),
      'b': Runnable.fromFunction((
        final Map<String, String> input,
        final options,
      ) async {
        final foo = input['foo'] ?? '';
        final bar = input['bar'] ?? '';
        return '${bar.length * foo.length}';
      }),
    }) |
    promptTemplate |
    model |
    StringOutputParser();

final res = await chain.invoke({'foo': 'foo', 'bar': 'bar'});
print(res);
// 3 + 9 = 12
Inheritance
Available extensions

Constructors

RunnableFunction({FutureOr<RunOutput> invoke(RunInput input, RunnableOptions? options)?, Stream<RunOutput> stream(Stream<RunInput> inputStream, RunnableOptions? options)?, RunnableOptions defaultOptions = const RunnableOptions()})
A RunnableFunction allows you to run a Dart function as part of a chain.
const

Properties

defaultOptions → RunnableOptions
The default options to use when invoking the Runnable.
finalinherited
hashCode → int
The hash code for this object.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited

Methods

batch(List<RunInput> inputs, {List<RunnableOptions>? options}) → Future<List<RunOutput>>
Batches the invocation of the Runnable on the given inputs.
inherited
bind(RunnableOptions options) → RunnableBinding<RunInput, RunnableOptions, RunOutput>
Binds the Runnable to the given options.
inherited
close() → void
Cleans up any resources associated with it the Runnable.
inherited
getCompatibleOptions(RunnableOptions? options) → RunnableOptions?
Returns the given options if they are compatible with the Runnable, otherwise returns null.
inherited
invoke(RunInput input, {RunnableOptions? options}) → Future<RunOutput>
Invokes the RunnableFunction on the given input.
override
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
pipe<NewRunOutput extends Object?, NewCallOptions extends RunnableOptions>(Runnable<RunOutput, NewCallOptions, NewRunOutput> next) → RunnableSequence<RunInput, NewRunOutput>
Pipes the output of this Runnable into another Runnable using a RunnableSequence.
inherited
stream(RunInput input, {RunnableOptions? options}) → Stream<RunOutput>
Streams the input through the RunnableFunction.
override
streamFromInputStream(Stream<RunInput> inputStream, {RunnableOptions? options}) → Stream<RunOutput>
Streams the output of invoking the Runnable on the given inputStream.
override
toString() → String
A string representation of this object.
inherited
withFallbacks(List<Runnable<RunInput, RunnableOptions, RunOutput>> fallbacks) → RunnableWithFallback<RunInput, RunOutput>
Adds fallback runnables to be invoked if the primary runnable fails.
inherited

Operators

operator ==(Object other) → bool
The equality operator.
inherited