feat: add AskReadDecomposeAsk approach (WIP) (#30)

packages/api/src/lib/approaches/ask-read-decompose-ask.ts

@@ -0,0 +1,149 @@
+import { SearchClient } from '@azure/search-documents';
+import { DynamicTool } from 'langchain/tools';
+import { PromptTemplate } from 'langchain/prompts';
+import { initializeAgentExecutorWithOptions } from 'langchain/agents';
+import { OpenAiService } from '../../plugins/openai.js';
+import { LangchainService } from '../../plugins/langchain.js';
+import { AskApproach } from './approach.js';
+import { ApproachBase } from './approach-base.js';
+
+const EXAMPLES = [
+  `Question: What is the elevation range for the area that the eastern sector of the Colorado orogeny extends into?
+Thought: I need to search Colorado orogeny, find the area that the eastern sector of the Colorado orogeny extends into, then find the elevation range of the area.
+Action: Search[Colorado orogeny]
+Observation: <info1.pdf> The Colorado orogeny was an episode of mountain building (an orogeny) in Colorado and surrounding areas.
+Thought: It does not mention the eastern sector. So I need to look up eastern sector.
+Action: Lookup[eastern sector]
+Observation: <info2.txt> (Result 1 / 1) The eastern sector extends into the High Plains and is called the Central Plains orogeny.
+Thought: The eastern sector of Colorado orogeny extends into the High Plains. So I need to search High Plains and find its elevation range.
+Action: Search[High Plains]
+Observation: <some_file.pdf> High Plains refers to one of two distinct land regions
+Thought: I need to instead search High Plains (United States).
+Action: Search[High Plains (United States)]
+Observation: <filea.pdf> The High Plains are a subregion of the Great Plains. <another-ref.docx> From east to west, the High Plains rise in elevation from around 1,800 to 7,000 ft (550 to 2,130 m).
+Thought: High Plains rise in elevation from around 1,800 to 7,000 ft, so the answer is 1,800 to 7,000 ft.
+Action: Finish[1,800 to 7,000 ft <filea.pdf>]`,
+  `Question: Musician and satirist Allie Goertz wrote a song about the "The Simpsons" character Milhouse, who Matt Groening named after who?
+Thought: The question simplifies to "The Simpsons" character Milhouse is named after who. I only need to search Milhouse and find who it is named after.
+Action: Search[Milhouse]
+Observation: <info7.pdf> Milhouse Mussolini Van Houten is a recurring character in the Fox animated television series The Simpsons voiced by Pamela Hayden and created by Matt Groening.
+Thought: The paragraph does not tell who Milhouse is named after, maybe I can look up "named after".
+Action: Lookup[named after]
+Observation: <historyref2.txt> (Result 1 / 1) Milhouse was named after U.S. president Richard Nixon, whose middle name was Milhous.
+Thought: Milhouse was named after U.S. president Richard Nixon, so the answer is Richard Nixon.
+Action: Finish[Richard Nixon <historyref2.txt>]`,
+  `Question: Which documentary is about Finnish rock groups, Adam Clayton Powell or The Saimaa Gesture?
+Thought: I need to search Adam Clayton Powell and The Saimaa Gesture, and find which documentary is about Finnish rock groups.
+Action: Search[Adam Clayton Powell]
+Observation: <info9.pdf> Could not find [Adam Clayton Powell]. Similar: ['Adam Clayton Powell III', 'Seventh Avenue (Manhattan)', 'Adam Clayton Powell Jr. State Office Building', 'Isabel Washington Powell', 'Adam Powell', vAdam Clayton Powell (film)', 'Giancarlo Esposito'].
+Thought: To find the documentary, I can search Adam Clayton Powell (film).
+Action: Search[Adam Clayton Powell (film)]
+Observation: <data123.txt> Adam Clayton Powell is a 1989 American documentary film directed by Richard Kilberg. The film is about the rise and fall of influential African-American politician Adam Clayton Powell Jr.[3][4] It was later aired as part of the PBS series The American Experience.
+Thought: Adam Clayton Powell (film) is a documentary about an African-American politician, not Finnish rock groups. So the documentary about Finnish rock groups must instead be The Saimaa Gesture.
+Action: Finish[The Saimaa Gesture <data123.txt>]`,
+  `Question: What profession does Nicholas Ray and Elia Kazan have in common?
+Thought: I need to search Nicholas Ray and Elia Kazan, find their professions, then find the profession they have in common.
+Action: Search[Nicholas Ray]
+Observation: <files-987.png> Nicholas Ray (born Raymond Nicholas Kienzle Jr., August 7, 1911 - June 16, 1979) was an American film director, screenwriter, and actor best known for the 1955 film Rebel Without a Cause.
+Thought: Professions of Nicholas Ray are director, screenwriter, and actor. I need to search Elia Kazan next and find his professions.
+Action: Search[Elia Kazan]
+Observation: <files-654.txt> Elia Kazan was an American film and theatre director, producer, screenwriter and actor.
+Thought: Professions of Elia Kazan are director, producer, screenwriter, and actor. So profession Nicholas Ray and Elia Kazan have in common is director, screenwriter, and actor.
+Action: Finish[director, screenwriter, actor <files-987.png><files-654.txt>]`,
+  `Question: Which magazine was started first Arthur's Magazine or First for Women?
+Thought: I need to search Arthur's Magazine and First for Women, and find which was started first.
+Action: Search[Arthur's Magazine]
+Observation: <magazines-1850.pdf> Arthur's Magazine (1844-1846) was an American literary periodical published in Philadelphia in the 19th century.
+Thought: Arthur's Magazine was started in 1844. I need to search First for Women next.
+Action: Search[First for Women]
+Observation: <magazines-1900.pdf> First for Women is a woman's magazine published by Bauer Media Group in the USA.[1] The magazine was started in 1989.
+Thought: First for Women was started in 1989. 1844 (Arthur's Magazine) < 1989 (First for Women), so Arthur's Magazine was started first.
+Action: Finish[Arthur's Magazine <magazines-1850.pdf><magazines-1900.pdf>]`,
+  `Question: Were Pavel Urysohn and Leonid Levin known for the same type of work?
+Thought: I need to search Pavel Urysohn and Leonid Levin, find their types of work, then find if they are the same.
+Action: Search[Pavel Urysohn]
+Observation: <info4444.pdf> Pavel Samuilovich Urysohn (February 3, 1898 - August 17, 1924) was a Soviet mathematician who is best known for his contributions in dimension theory.
+Thought: Pavel Urysohn is a mathematician. I need to search Leonid Levin next and find its type of work.
+Action: Search[Leonid Levin]
+Observation: <datapoints_aaa.txt> Leonid Anatolievich Levin is a Soviet-American mathematician and computer scientist.
+Thought: Leonid Levin is a mathematician and computer scientist. So Pavel Urysohn and Leonid Levin have the same type of work.
+Action: Finish[yes <info4444.pdf><datapoints_aaa.txt>]`,
+];
+
+const SUFFIX = `\nQuestion: {input}\n{agent_scratchpad}`;
+const PREFIX =
+  'Answer questions as shown in the following examples, by splitting the question into individual search or lookup actions to find facts until you can answer the question. ' +
+  'Observations are prefixed by their source name in angled brackets, source names MUST be included with the actions in the answers.' +
+  'All questions must be answered from the results from search or look up actions, only facts resulting from those can be used in an answer. ' +
+  'Answer questions as truthfully as possible, and ONLY answer the questions using the information from observations, do not speculate or your own knowledge.';
+
+export class AskReadDecomposeAsk extends ApproachBase implements AskApproach {
+  constructor(
+    private langchain: LangchainService,
+    search: SearchClient<any>,
+    openai: OpenAiService,
+    chatGptModel: string,
+    sourcePageField: string,
+    contentField: string,
+  ) {
+    super(search, openai, chatGptModel, sourcePageField, contentField);
+  }
+
+  async run(userQuery: string, overrides: Record<string, any>): Promise<any> {
+    let searchResults: string[] = [];
+
+    const searchAndStore = async (query: string): Promise<string> => {
+      const { results, content } = await this.searchDocuments(query, overrides);
+      searchResults = results;
+      return content;
+    };
+
+    const chatModel = await this.langchain.getChat({
+      temperature: overrides?.temperature || 0.3,
+    });
+
+    const tools = [
+      new DynamicTool({
+        name: 'Search',
+        func: searchAndStore,
+        description: 'useful for when you need to ask with search',
+      }),
+      new DynamicTool({
+        name: 'Lookup',
+        func: (query: string) => this.lookupDocument(query),
+        description: 'useful for when you need to ask with lookup',
+      }),
+    ];
+
+    // TODO: port ReactDocStore agent
+
+    const promptPrefix = overrides?.promptTemplate;
+    const prompt = PromptTemplate.fromExamples(
+      EXAMPLES,
+      SUFFIX,
+      ['input', 'agent_scratchpad'],
+      undefined,
+      promptPrefix ? `${promptPrefix}\n\n${PREFIX}` : PREFIX,
+    );
+
+    // TODO: remove
+    console.log(prompt);
+
+    const executor = await initializeAgentExecutorWithOptions(tools, chatModel, {
+      agentType: 'chat-zero-shot-react-description', // "structured-chat-zero-shot-react-description" in types
+      returnIntermediateSteps: true,
+      verbose: true,
+    });
+    const result = await await executor.call({ input: userQuery });
+
+    // Replace substrings of the form <file.ext> with [file.ext] so that the frontend can render them as links,
+    // match them with a regex to avoid generalizing too much and disrupt HTML snippets if present
+    const formattedResult = result.replace(/<([a-zA-Z0-9_ \-.]+)>/g, '[$1]');
+
+    return {
+      data_points: searchResults,
+      answer: formattedResult,
+      thoughts: `Though process:\n${JSON.stringify(result.intermediateSteps, null, 2)}`, // TODO: format to HTML?
+    };
+  }
+}

packages/api/src/lib/approaches/index.ts

@@ -1,4 +1,5 @@
 export * from './approach.js';
 export * from './ask-retrieve-then-read.js';
+export * from './ask-read-decompose-ask.js';
 export * from './ask-read-retrieve-read.js';
 export * from './chat-read-retrieve-read.js';

packages/api/src/plugins/approaches.ts

@@ -1,6 +1,7 @@
 import fp from 'fastify-plugin';
 import {
   AskApproach,
+  AskReadDecomposeAsk,
   AskReadRetrieveRead,
   AskRetrieveThenRead,
   ChatApproach,
@@ -45,6 +46,14 @@ export default fp(
           config.kbFieldsSourcePage,
           config.kbFieldsContent,
         ),
+        rda: new AskReadDecomposeAsk(
+          fastify.langchain,
+          fastify.azure.search,
+          fastify.openai,
+          config.azureOpenAiChatGptModel,
+          config.kbFieldsSourcePage,
+          config.kbFieldsContent,
+        ),
       },
     });
   },