chore: copied doc-workflow example from CL

examples/agents/workflow/doc-workflow.ts

@@ -0,0 +1,332 @@
+import { ChatMemoryBuffer, ChatMessage, LLM, MessageContent } from "llamaindex";
+
+import {
+  agentStreamEvent,
+  createStatefulMiddleware,
+  createWorkflow,
+  startAgentEvent,
+  stopAgentEvent,
+  workflowEvent,
+} from "@llamaindex/workflow";
+
+import { z } from "zod";
+
+export const DocumentRequirementSchema = z.object({
+  type: z.enum(["markdown", "html"]),
+  title: z.string(),
+  requirement: z.string(),
+});
+
+export type DocumentRequirement = z.infer<typeof DocumentRequirementSchema>;
+
+export const UIEventSchema = z.object({
+  type: z.literal("ui_event"),
+  data: z.object({
+    state: z
+      .enum(["plan", "generate", "completed"])
+      .describe(
+        "The current state of the workflow: 'plan', 'generate', or 'completed'.",
+      ),
+    requirement: z
+      .string()
+      .optional()
+      .describe(
+        "An optional requirement creating or updating a document, if applicable.",
+      ),
+  }),
+});
+export type UIEvent = z.infer<typeof UIEventSchema>;
+export const uiEvent = workflowEvent<UIEvent>();
+
+const planEvent = workflowEvent<{
+  userInput: MessageContent;
+  context?: string | undefined;
+}>();
+
+const generateArtifactEvent = workflowEvent<{
+  requirement: DocumentRequirement;
+}>();
+
+const synthesizeAnswerEvent = workflowEvent<{
+  requirement: DocumentRequirement;
+  generatedArtifact: string;
+}>();
+
+const ArtifactSchema = z.object({
+  type: z.literal("artifact"),
+  data: z.object({
+    type: z.literal("document"),
+    data: z.object({
+      title: z.string(),
+      content: z.string(),
+      type: z.string(),
+    }),
+    created_at: z.number(),
+  }),
+});
+export type Artifact = z.infer<typeof ArtifactSchema>;
+export const artifactEvent = workflowEvent<Artifact>();
+
+export function createDocumentArtifactWorkflow(
+  llm: LLM,
+  chatHistory: ChatMessage[],
+  lastArtifact: Artifact | undefined,
+) {
+  const { withState, getContext } = createStatefulMiddleware(() => {
+    return {
+      memory: new ChatMemoryBuffer({
+        llm,
+        chatHistory: chatHistory,
+      }),
+      lastArtifact: lastArtifact,
+    };
+  });
+  const workflow = withState(createWorkflow());
+
+  workflow.handle([startAgentEvent], async ({ data: { userInput } }) => {
+    // Prepare chat history
+    const { state } = getContext();
+    // Put user input to the memory
+    if (!userInput) {
+      throw new Error("Missing user input to start the workflow");
+    }
+    state.memory.put({
+      role: "user",
+      content: userInput,
+    });
+    return planEvent.with({
+      userInput,
+      context: state.lastArtifact
+        ? JSON.stringify(state.lastArtifact)
+        : undefined,
+    });
+  });
+
+  workflow.handle([planEvent], async ({ data: planData }) => {
+    const { sendEvent } = getContext();
+    const { state } = getContext();
+    sendEvent(
+      uiEvent.with({
+        type: "ui_event",
+        data: {
+          state: "plan",
+        },
+      }),
+    );
+    const user_msg = planData.userInput;
+    const context = planData.context
+      ? `## The context is: \n${planData.context}\n`
+      : "";
+    const prompt = `
+         You are a documentation analyst responsible for analyzing the user's request and providing requirements for document generation or update.
+         Follow these instructions:
+         1. Carefully analyze the conversation history and the user's request to determine what has been done and what the next step should be.
+         2. From the user's request, provide requirements for the next step of the document generation or update.
+         3. Do not be verbose; only return the requirements for the next step of the document generation or update.
+         4. Only the following document types are allowed: "markdown", "html".
+         5. The requirement should be in the following format:
+            \`\`\`json
+            {
+                "type": "markdown" | "html",
+                "title": string,
+                "requirement": string
+            }
+            \`\`\`
+
+         ## Example:
+         User request: Create a project guideline document.
+         You should return:
+         \`\`\`json
+         {
+             "type": "markdown",
+             "title": "Project Guideline",
+             "requirement": "Generate a Markdown document that outlines the project goals, deliverables, and timeline. Include sections for introduction, objectives, deliverables, and timeline."
+         }
+         \`\`\`
+
+         User request: Add a troubleshooting section to the guideline.
+         You should return:
+         \`\`\`json
+         {
+             "type": "markdown",
+             "title": "Project Guideline",
+             "requirement": "Add a 'Troubleshooting' section at the end of the document with common issues and solutions."
+         }
+         \`\`\`
+
+         ${context}
+
+         Now, please plan for the user's request:
+         ${user_msg}
+        `;
+
+    const response = await llm.complete({
+      prompt,
+    });
+    // Parse the response to DocumentRequirement
+    const jsonBlock = response.text.match(/```json\s*([\s\S]*?)\s*```/);
+    if (!jsonBlock) {
+      throw new Error("No JSON block found in the response.");
+    }
+    const requirement = DocumentRequirementSchema.parse(
+      JSON.parse(jsonBlock[1]),
+    );
+    state.memory.put({
+      role: "assistant",
+      content: `Planning for the document generation: \n${response.text}`,
+    });
+    return generateArtifactEvent.with({
+      requirement,
+    });
+  });
+
+  workflow.handle(
+    [generateArtifactEvent],
+    async ({ data: { requirement } }) => {
+      const { sendEvent } = getContext();
+      const { state } = getContext();
+
+      sendEvent(
+        uiEvent.with({
+          type: "ui_event",
+          data: {
+            state: "generate",
+            requirement: requirement.requirement,
+          },
+        }),
+      );
+
+      const previousArtifact = state.lastArtifact
+        ? JSON.stringify(state.lastArtifact)
+        : "";
+      const requirementStr = JSON.stringify(requirement);
+
+      const prompt = `
+         You are a skilled technical writer who can help users with documentation.
+         You are given a task to generate or update a document for a given requirement.
+
+         ## Follow these instructions:
+         **1. Carefully read the user's requirements.**
+            If any details are ambiguous or missing, make reasonable assumptions and clearly reflect those in your output.
+            If the previous document is provided:
+            + Carefully analyze the document with the request to make the right changes.
+            + Avoid making unnecessary changes from the previous document if the request is not to rewrite it from scratch.
+         **2. For document requests:**
+            - If the user does not specify a type, default to Markdown.
+            - Ensure the document is clear, well-structured, and grammatically correct.
+            - Only generate content relevant to the user's request—do not add extra boilerplate.
+         **3. Do not be verbose in your response.**
+            - No other text or comments; only return the document content wrapped by the appropriate code block (\`\`\`markdown or \`\`\`html).
+            - If the user's request is to update the document, only return the updated document.
+         **4. Only the following types are allowed: "markdown", "html".**
+         **5. If there is no change to the document, return the reason without any code block.**
+
+         ## Example:
+         \`\`\`markdown
+         # Project Guideline
+
+         ## Introduction
+         ...
+         \`\`\`
+
+         The previous content is:
+         ${previousArtifact}
+
+         Now, please generate the document for the following requirement:
+         ${requirementStr}
+      `;
+
+      const response = await llm.complete({
+        prompt,
+      });
+
+      // Extract the document from the response
+      const docMatch = response.text.match(/```(markdown|html)([\s\S]*)```/);
+      const generatedContent = response.text;
+
+      if (docMatch) {
+        const content = docMatch[2].trim();
+        const docType = docMatch[1] as "markdown" | "html";
+
+        // Put the generated document to the memory
+        state.memory.put({
+          role: "assistant",
+          content: `Generated document: \n${response.text}`,
+        });
+
+        // To show the Canvas panel for the artifact
+        sendEvent(
+          artifactEvent.with({
+            type: "artifact",
+            data: {
+              type: "document",
+              created_at: Date.now(),
+              data: {
+                title: requirement.title,
+                content: content,
+                type: docType,
+              },
+            },
+          }),
+        );
+      }
+
+      return synthesizeAnswerEvent.with({
+        requirement,
+        generatedArtifact: generatedContent,
+      });
+    },
+  );
+
+  workflow.handle([synthesizeAnswerEvent], async ({ data }) => {
+    const { sendEvent } = getContext();
+    const { state } = getContext();
+
+    const chatHistory = await state.memory.getMessages();
+    const messages = [
+      ...chatHistory,
+      {
+        role: "system" as const,
+        content: `
+                Your responsibility is to explain the work to the user.
+                If there is no document to update, explain the reason.
+                If the document is updated, just summarize what changed. Don't need to include the whole document again in the response.
+                `,
+      },
+    ];
+
+    const responseStream = await llm.chat({
+      messages,
+      stream: true,
+    });
+
+    sendEvent(
+      uiEvent.with({
+        type: "ui_event",
+        data: {
+          state: "completed",
+          requirement: data.requirement.requirement,
+        },
+      }),
+    );
+
+    let response = "";
+    for await (const chunk of responseStream) {
+      response += chunk.delta;
+      sendEvent(
+        agentStreamEvent.with({
+          delta: chunk.delta,
+          response: "",
+          currentAgentName: "assistant",
+          raw: chunk,
+        }),
+      );
+    }
+
+    return stopAgentEvent.with({
+      result: response,
+    });
+  });
+
+  return workflow;
+}