feat(js/plugins/ollama): migrate ollama plugin to v2 plugin API

[HassanBahati]

Fixes #3456

Plugin migration guide

Changes of note:

• We're no longer getting serverAddress from config, because it doesn't exist on that interface any more in v2 API.

Checklist (if applicable):

• PR title is following https://www.conventionalcommits.org/en/v1.0.0/

• Tested (integration, unit)

• Docs updated (updated docs or a docs bug required)

• Updated and added integration tests with the core genkit framework, for streaming responses and tool calls.

• All existing plugin tests pass

In the process of manually testing the plugin.

[cabljac]

We should factor these out into helpers (like in original)

[cabljac]

We probably should handle the case where someone tries to resolve an embedder?

[cabljac]

need to double check this, make sure we're not breaking anything by removing config.serverAddress

[dackers86]

Checking if we meant to switch off the glob testing for this package?

[dackers86]

Is there a reason this is called actionName and not name?

[dackers86]

Suggested change

	function ollamaPlugin(params?: OllamaPluginParams): GenkitPluginV2 {
	if (!params) {
	params = {};
	}
	function ollamaPlugin(params?: OllamaPluginParams = {}): GenkitPluginV2 {

[dackers86]

Suggested change

	if (!params.serverAddress) {
	params.serverAddress = DEFAULT_OLLAMA_SERVER_ADDRESS;
	}
	const serverAddress = params.serverAddress;
	const serverAddress = params.serverAddress || DEFAULT_OLLAMA_SERVER_ADDRESS;

[dackers86]

Could this be extracted into a helper function?

function getModelActions(params: OllamaPluginParams, serverAddress: string): ResolvableAction[] {
  /** Extract variables **/
  const { models, requestHeaders } = params;

  /** If no models, return empty array; **/
  if (!models || !models.length) return [];
  
 /** Return Ollama models **/
  return models.map(m => createOllamaModel(m, serverAddress, requestHeaders));
}

init() {
  return [
    ...getModelActions(params, serverAddress),
    ...getEmbedderActions(params, serverAddress)
  ];
}

[dackers86]

Is there a reason why we removed the resolveAction function? The original resolveActionWe can return early if undefined. Also should we return undefined here.

Suggested change

	if (actionType === 'model') {
	return await createOllamaModel(
	{
	name: actionName,
	},
	serverAddress,
	params?.requestHeaders
	);
	}
	return undefined;
	},
	async resolve(actionType, actionName) {
	/** If no model actions, return undefined **/
	if (actionType !== 'model') return undefined;
	return await createOllamaModel(
	{
	name: actionName,
	},
	serverAddress,
	params?.requestHeaders
	);
	}