Ollama class

Wrapper around Ollama Completions API.

Ollama allows you to run open-source large language models, such as Llama 3 or LLaVA, locally.

For a complete list of supported models and model variants, see the Ollama model library.

Example:

final llm = Ollama(
  defaultOption: const OllamaOptions(
    model: 'llama3.2',
    temperature: 1,
  ),
);
final prompt = PromptValue.string('Hello world!');
final result = await openai.invoke(prompt);

Ollama base URL

By default, Ollama uses 'http://localhost:11434/api' as base URL (default Ollama API URL). But if you are running Ollama on a different one, you can override it using the baseUrl parameter.

Call options

You can configure the parameters that will be used when calling the completions API in several ways:

Default options:

Use the defaultOptions parameter to set the default options. These options will be used unless you override them when generating completions.

final llm = Ollama(
  defaultOptions: const OllamaOptions(
    model: 'llama3.2',
    temperature: 0,
    format: 'json',
  ),
);
final prompt = PromptValue.string('Hello world!');
final result = await openai.invoke(prompt);

Call options:

You can override the default options when invoking the model:

final res = await llm.invoke(
  prompt,
  options: const OllamaOptions(seed: 9999),
);

Bind:

You can also change the options in a Runnable pipeline using the bind method.

In this example, we are using two totally different models for each question:

final llm = Ollama();
const outputParser = StringOutputParser();
final prompt1 = PromptTemplate.fromTemplate('How are you {name}?');
final prompt2 = PromptTemplate.fromTemplate('How old are you {name}?');
final chain = Runnable.fromMap({
  'q1': prompt1 | llm.bind(const OllamaOptions(model: 'llama3.2')) | outputParser,
  'q2': prompt2| llm.bind(const OllamaOptions(model: 'mistral')) | outputParser,
});
final res = await chain.invoke({'name': 'David'});

Setup

  1. Download and install Ollama
  2. Fetch a model via ollama pull <model family>
  • e.g., for Llama-7b: ollama pull llama3.2

Advance

Custom HTTP client

You can always provide your own implementation of http.Client for further customization:

final client = Ollama(
  client: MyHttpClient(),
);

Using a proxy

HTTP proxy

You can use your own HTTP proxy by overriding the baseUrl and providing your required headers:

final client = Ollama(
  baseUrl: 'https://my-proxy.com',
  headers: {'x-my-proxy-header': 'value'},
  queryParams: {'x-my-proxy-query-param': 'value'},
);

If you need further customization, you can always provide your own http.Client.

SOCKS5 proxy

To use a SOCKS5 proxy, you can use the socks5_proxy package and a custom http.Client.

Constructors

Ollama({String baseUrl = 'http://localhost:11434/api', Map<String, String>? headers, Map<String, dynamic>? queryParams, Client? client, OllamaOptions defaultOptions = const OllamaOptions(model: defaultModel), String encoding = 'cl100k_base'})
Create a new Ollama instance.

Properties

defaultOptions OllamaOptions
The default options to use when invoking the Runnable.
finalinherited
encoding String
The encoding to use by tiktoken when tokenize is called.
getter/setter pair
hashCode int
The hash code for this object.
no setterinherited
modelType String
Return type of language model.
no setter
runtimeType Type
A representation of the runtime type of the object.
no setterinherited

Methods

batch(List<PromptValue> inputs, {List<OllamaOptions>? options}) Future<List<LLMResult>>
Batches the invocation of the Runnable on the given inputs.
inherited
bind(OllamaOptions options) → RunnableBinding<PromptValue, OllamaOptions, LLMResult>
Binds the Runnable to the given options.
inherited
call(String prompt, {OllamaOptions? options}) Future<String>
Runs the LLM on the given String prompt and returns a String with the generated text.
inherited
close() → void
Cleans up any resources associated with it the Runnable.
countTokens(PromptValue promptValue, {OllamaOptions? options}) Future<int>
Returns the number of tokens resulting from tokenize the given prompt.
inherited
getCompatibleOptions(RunnableOptions? options) OllamaOptions?
Returns the given options if they are compatible with the Runnable, otherwise returns null.
inherited
invoke(PromptValue input, {OllamaOptions? options}) Future<LLMResult>
Invokes the Runnable on the given input.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
pipe<NewRunOutput extends Object?, NewCallOptions extends RunnableOptions>(Runnable<LLMResult, NewCallOptions, NewRunOutput> next) → RunnableSequence<PromptValue, NewRunOutput>
Pipes the output of this Runnable into another Runnable using a RunnableSequence.
inherited
stream(PromptValue input, {OllamaOptions? options}) Stream<LLMResult>
Streams the output of invoking the Runnable on the given input.
streamFromInputStream(Stream<PromptValue> inputStream, {OllamaOptions? options}) Stream<LLMResult>
Streams the output of invoking the Runnable on the given inputStream.
inherited
tokenize(PromptValue promptValue, {OllamaOptions? options}) Future<List<int>>
Tokenizes the given prompt using tiktoken.
toString() String
A string representation of this object.
inherited
withFallbacks(List<Runnable<PromptValue, RunnableOptions, LLMResult>> fallbacks) → RunnableWithFallback<PromptValue, LLMResult>
Adds fallback runnables to be invoked if the primary runnable fails.
inherited
withRetry({int maxRetries = 3, FutureOr<bool> retryIf(Object e)?, List<Duration?>? delayDurations, bool addJitter = false}) → RunnableRetry<PromptValue, LLMResult>
Adds retry logic to an existing runnable.
inherited

Operators

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

Constants

defaultModel → const String
The default model to use unless another is specified.