Starting to modularize into separate cli / server packages. (#55)

* Starting to move a lot of code into packages/server

* More of the massive refactor, builds and runs, some issues though.

* Fixing outstanding issue with double messages.

* Fixing a minor UI issue.

* Fixing the build post-merge.

* Running formatting.

* Addressing comments.

packages/server/src/tools/web-fetch.ts

@@ -0,0 +1,141 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { SchemaValidator } from '../utils/schemaValidator.js';
+import { BaseTool, ToolResult } from './tools.js';
+import { getErrorMessage } from '../utils/errors.js';
+
+/**
+ * Parameters for the WebFetch tool
+ */
+export interface WebFetchToolParams {
+  /**
+   * The URL to fetch content from.
+   */
+  url: string;
+}
+
+/**
+ * Implementation of the WebFetch tool logic (moved from CLI)
+ */
+export class WebFetchLogic extends BaseTool<WebFetchToolParams, ToolResult> {
+  static readonly Name: string = 'web_fetch';
+
+  constructor() {
+    super(
+      WebFetchLogic.Name,
+      '', // Display name handled by CLI wrapper
+      '', // Description handled by CLI wrapper
+      {
+        properties: {
+          url: {
+            description:
+              "The URL to fetch. Must be an absolute URL (e.g., 'https://example.com/file.txt').",
+            type: 'string',
+          },
+        },
+        required: ['url'],
+        type: 'object',
+      },
+    );
+  }
+
+  validateParams(params: WebFetchToolParams): string | null {
+    if (
+      this.schema.parameters &&
+      !SchemaValidator.validate(
+        this.schema.parameters as Record<string, unknown>,
+        params,
+      )
+    ) {
+      return 'Parameters failed schema validation.';
+    }
+    try {
+      const parsedUrl = new URL(params.url);
+      if (!['http:', 'https:'].includes(parsedUrl.protocol)) {
+        return `Invalid URL protocol: "${parsedUrl.protocol}". Only 'http:' and 'https:' are supported.`;
+      }
+    } catch {
+      return `Invalid URL format: "${params.url}". Please provide a valid absolute URL (e.g., 'https://example.com').`;
+    }
+    return null;
+  }
+
+  getDescription(params: WebFetchToolParams): string {
+    const displayUrl =
+      params.url.length > 80 ? params.url.substring(0, 77) + '...' : params.url;
+    return `Fetching content from ${displayUrl}`;
+  }
+
+  // Removed shouldConfirmExecute - handled by CLI
+
+  async execute(params: WebFetchToolParams): Promise<ToolResult> {
+    const validationError = this.validateParams(params);
+    if (validationError) {
+      return {
+        llmContent: `Error: Invalid parameters provided. Reason: ${validationError}`,
+        returnDisplay: `Error: ${validationError}`,
+      };
+    }
+
+    const url = params.url;
+
+    try {
+      const response = await fetch(url, {
+        headers: {
+          // Identify the client making the request
+          'User-Agent': 'GeminiCode-ServerLogic/1.0',
+        },
+        signal: AbortSignal.timeout(15000), // Use AbortSignal for timeout
+      });
+
+      if (!response.ok) {
+        const errorText = `Failed to fetch data from ${url}. Status: ${response.status} ${response.statusText}`;
+        return {
+          llmContent: `Error: ${errorText}`,
+          returnDisplay: `Error: ${errorText}`,
+        };
+      }
+
+      // Basic check for text-based content types
+      const contentType = response.headers.get('content-type') || '';
+      if (
+        !contentType.includes('text/') &&
+        !contentType.includes('json') &&
+        !contentType.includes('xml')
+      ) {
+        const errorText = `Unsupported content type: ${contentType} from ${url}`;
+        return {
+          llmContent: `Error: ${errorText}`,
+          returnDisplay: `Error: ${errorText}`,
+        };
+      }
+
+      const data = await response.text();
+      const MAX_LLM_CONTENT_LENGTH = 200000; // Truncate large responses
+      const truncatedData =
+        data.length > MAX_LLM_CONTENT_LENGTH
+          ? data.substring(0, MAX_LLM_CONTENT_LENGTH) +
+            '\n... [Content truncated]'
+          : data;
+
+      const llmContent = data
+        ? `Fetched data from ${url}:\n\n${truncatedData}`
+        : `No text data fetched from ${url}. Status: ${response.status}`; // Adjusted message for clarity
+
+      return {
+        llmContent,
+        returnDisplay: `Fetched content from ${url}`,
+      };
+    } catch (error: unknown) {
+      const errorMessage = `Failed to fetch data from ${url}. Error: ${getErrorMessage(error)}`;
+      return {
+        llmContent: `Error: ${errorMessage}`,
+        returnDisplay: `Error: ${errorMessage}`,
+      };
+    }
+  }
+}