Create GenerativeTextTemplate that streamlines usage of AiClient, Prompts, and OutputParsers

[markpollack]

There is an analogy to make between GenerationTemplate and JdbcTemplate that will help simplify the use of the lower level classes such as AiClient, Prompts, and OutputParsers. Note: AiClient should likely be renamed GenerationClient as it is focused on generation, specifcally text, so perhaps even TextGenerationClient as we haven't yet experimented with multi-modal apis.

DataSource <-> AiClient

String Query with placeholdres <-> Prompt with placeholders

RowMapper <-> OutputParser

The simplest method (which is a default method in AiClient) is string input and string output, that could be removed from the AiClient interface and used in GenerateTemplate instead. Here are a few sample signatures for consideration.

public interface GenerateOperations {

	String generate(String message);

	String generate(String message, Map<String, Object> model)

	String generate(PromptTemplate promptTemplate, Map<String, Object> model);
	
	<T> T generate(String message, Class<T> elementType, Map<String, Object> model);

	<T> T generate(String message, OutputParser<T> parser, Map<String, Object> model);

	<T> List<T> generateList(String message, Class<T> elementType, Map<String, Object> model);

	<T> List<T> generateList(String message, OutputParser<T> parser, Map<String, Object> model);

        AiResponse generateResponse(PromptTemplate promptTemplate, Map<String, Object> model);
}

Example usage

ActorsFilms actorsFilms = generateTemplate.generate("Generate the filmography for the actor {actor}",
 		                                    ActorsFilms.class, Map.of("actor", "Tom Hanks"));

Simple "chains" for flows can be done with standard Java functional programming, and we can see how our needs for a "chain" or a "flow" evolve over time. e.g. the example of a chain from langchain using functional programming

	@Test
	void functionalChains() {
		Function<String, String> combinedFunction = generateSynopsis.andThen(generateReview);
		System.out.println(combinedFunction.apply("Tragedy at sunset on the beach"));
	}

	private Function<String, String> generateSynopsis = title -> {
		String synopsisInput = """
				You are a playwright. Given the title of play, it is your job to write a synopsis for that title.

				Title: {title}
				Playwright: This is a synopsis for the above play:""";

		return generateTemplate.generate(synopsisInput, Map.of("title", title));
	};

	private Function<String, String> generateReview = synopsis -> {
		String synopsisInput = """
				You are a play critic from the New York Times. Given the synopsis of play, it is your job to write a review for that play.

				Play Synopsis:
				{synopsis}
				Review from a New York Times play critic of the above play:""";

		return generateTemplate.generate(synopsisInput, Map.of("synopsis", synopsis));
	};

[markpollack]

As a note, a new issue to create a 'GenerateTextOperation' class that has a fluent api, akin to SimpleJdbcCall and company

[markpollack]

this has been addressed with the fluent api in the updated chatclient.