Merge pull request 'feat(DIS-102): sanitizeForDiscord strips paths and tokens before Discord send' (#46) from phase-1/sanitize-for-discord into main

Reviewed-on: #46

src/agent/identity.ts

@@ -3,6 +3,7 @@ import * as path from "path";
 import * as YAML from "yaml";
 import { ZodError } from "zod";
 import { AgentYamlSchema } from "./schema";
+import type { AgentYaml as AgentIdentity } from "./schema";
 
 export type { AgentYaml as AgentIdentity } from "./schema";
 

src/config/loader.ts

@@ -6,6 +6,7 @@ import * as YAML from "yaml";
 import { ZodError } from "zod";
 import { childLogger } from "../runtime/logger";
 import { DisclawConfigSchema } from "./schema";
+import type { DisclawConfig } from "./schema";
 
 export type { DisclawConfig } from "./schema";
 

src/router.ts

@@ -1,7 +1,9 @@
+import * as os from "os";
 import { Message, TextChannel } from "discord.js";
 import { DisclawDatabase } from "./db/database";
 import { DisclawConfig } from "./config/loader";
 import { runAgent } from "./agent/runner";
+import { sanitizeForDiscord } from "./runtime/sanitize";
 
 const DISCORD_MAX_LENGTH = 2000;
 
@@ -105,8 +107,18 @@ export async function routeMessage(
       message.author.username
     );
 
+    // Sanitize the full response once, then use the sanitized version
+    // for both Discord output and conversation history storage.
+    // This prevents a feedback loop where raw paths in stored history
+    // get fed back to the agent as context, causing it to reproduce them.
+    const sanitizeOpts = {
+      repoRoot: workspace.workspace_path,
+      home: os.homedir(),
+    };
+    const sanitizedResponse = sanitizeForDiscord(response, sanitizeOpts);
+
     // Split and send response
-    const chunks = splitMessage(response);
+    const chunks = splitMessage(sanitizedResponse);
     let firstMsgId: string | null = null;
 
     for (const chunk of chunks) {
@@ -116,19 +128,23 @@ export async function routeMessage(
       }
     }
 
-    // Store assistant response (use first message id for dedup)
+    // Store sanitized assistant response (use first message id for dedup)
     if (firstMsgId) {
       db.addConversation(
         workspace.id,
         firstMsgId,
         "assistant",
-        response,
+        sanitizedResponse,
         null
       );
     }
   } catch (error) {
     const msg = error instanceof Error ? error.message : "Unbekannter Fehler";
-    await channel.send(`Fehler bei der Verarbeitung: ${msg}`).catch(() => {});
+    const safeMsg = sanitizeForDiscord(`Fehler bei der Verarbeitung: ${msg}`, {
+      repoRoot: workspace.workspace_path,
+      home: os.homedir(),
+    });
+    await channel.send(safeMsg).catch(() => {});
   } finally {
     clearInterval(typingInterval);
   }

src/runtime/sanitize.ts

@@ -0,0 +1,58 @@
+export interface SanitizeOptions {
+  repoRoot?: string; // e.g. /home/user/.disclaw
+  home?: string; // os.homedir()
+}
+
+/**
+ * Sanitizes agent output before it is sent to a Discord channel.
+ * Replaces absolute paths and sensitive tokens so they are never leaked.
+ *
+ * Replacement order is intentional — longest/most-specific patterns first:
+ *   1. repoRoot  → <disclaw>
+ *   2. home      → ~
+ *   3. Discord bot token pattern → <redacted>
+ *   4. Anthropic API key pattern → <redacted>
+ */
+/** Returns both backslash and forward-slash variants of a path (for Windows). */
+function pathVariants(p: string): string[] {
+  const fwd = p.replace(/\\/g, "/");
+  const bwd = p.replace(/\//g, "\\");
+  return fwd === bwd ? [p] : [p, fwd, bwd];
+}
+
+function replaceAll(text: string, search: string, replacement: string): string {
+  return text.split(search).join(replacement);
+}
+
+export function sanitizeForDiscord(
+  text: string,
+  opts: SanitizeOptions = {}
+): string {
+  let result = text;
+
+  // 1. Replace repo root before home so that sub-paths are caught by the
+  //    more specific substitution first (repoRoot is usually inside home).
+  if (opts.repoRoot) {
+    for (const variant of pathVariants(opts.repoRoot)) {
+      result = replaceAll(result, variant, "<disclaw>");
+    }
+  }
+
+  // 2. Replace home directory with ~ (both slash styles for Windows)
+  if (opts.home) {
+    for (const variant of pathVariants(opts.home)) {
+      result = replaceAll(result, variant, "~");
+    }
+  }
+
+  // 3. Discord bot token  — format: [MN]<23 base64url>.<6 base64url>.<27 base64url>
+  result = result.replace(
+    /[MN][A-Za-z\d]{23}\.[\w-]{6}\.[\w-]{27}/g,
+    "<redacted>"
+  );
+
+  // 4. Anthropic API key  — format: sk-ant-<20+ base64url chars>
+  result = result.replace(/sk-ant-[A-Za-z0-9\-_]{20,}/g, "<redacted>");
+
+  return result;
+}

tests/unit/sanitize-for-discord.test.ts

@@ -0,0 +1,87 @@
+import { describe, it, expect } from "vitest";
+import { sanitizeForDiscord } from "../../src/runtime/sanitize";
+
+describe("sanitizeForDiscord", () => {
+  // (a) Repo-root path is replaced with <disclaw>
+  it("replaces repoRoot with <disclaw>", () => {
+    const text = "Reading config from /home/user/project/disclaw.yaml";
+    const result = sanitizeForDiscord(text, { repoRoot: "/home/user/project" });
+    expect(result).toBe("Reading config from <disclaw>/disclaw.yaml");
+    expect(result).not.toContain("/home/user/project");
+  });
+
+  // (b) Home directory is replaced with ~
+  it("replaces home directory with ~", () => {
+    const text = "Workspace located at /home/user/.disclaw/workspaces/agent-x";
+    const result = sanitizeForDiscord(text, { home: "/home/user" });
+    expect(result).toBe("Workspace located at ~/.disclaw/workspaces/agent-x");
+    expect(result).not.toContain("/home/user");
+  });
+
+  // (c) Discord bot token pattern is redacted
+  it("redacts Discord bot tokens", () => {
+    const token = "MTA1NjYwNDczNTA3NDU2NjE2.GbXkRa.abcdefghijklmnopqrstuvwxyz123";
+    const text = `Bot initialized with token ${token} — ready.`;
+    const result = sanitizeForDiscord(text);
+    expect(result).not.toContain(token);
+    expect(result).toContain("<redacted>");
+  });
+
+  // (d) Anthropic API key is redacted
+  it("redacts Anthropic API keys", () => {
+    const key = "sk-ant-api03-ABCDEFGHIJ1234567890abcdefghij";
+    const text = `Using key ${key} for requests.`;
+    const result = sanitizeForDiscord(text);
+    expect(result).not.toContain(key);
+    expect(result).toContain("<redacted>");
+  });
+
+  // (e) Harmless text is not modified (no false positives)
+  it("does not modify harmless text", () => {
+    const text = "Hello! The agent processed your request successfully in 120ms.";
+    const result = sanitizeForDiscord(text, { home: "/home/user", repoRoot: "/home/user/project" });
+    expect(result).toBe(text);
+  });
+
+  // (f) Empty string returns empty string
+  it("handles empty string input", () => {
+    expect(sanitizeForDiscord("")).toBe("");
+    expect(sanitizeForDiscord("", { home: "/home/user", repoRoot: "/home/user/project" })).toBe("");
+  });
+
+  // (g) No opts provided — plain text stays unchanged when no token patterns present
+  it("returns text unchanged when no opts and no token patterns", () => {
+    const text = "This is a perfectly normal response from the agent.";
+    expect(sanitizeForDiscord(text)).toBe(text);
+  });
+
+  // Ordering: repoRoot (sub-path of home) is replaced before home
+  it("replaces repoRoot before home so nested paths are handled correctly", () => {
+    const text = "/home/user/project/src/index.ts and /home/user/other.ts";
+    const result = sanitizeForDiscord(text, {
+      repoRoot: "/home/user/project",
+      home: "/home/user",
+    });
+    expect(result).toBe("<disclaw>/src/index.ts and ~/other.ts");
+  });
+
+  // Windows-style backslash paths are sanitized
+  it("replaces Windows backslash paths", () => {
+    const text = "File at C:\\Users\\dev\\.disclaw\\workspaces\\agent-x\\src\\main.ts";
+    const result = sanitizeForDiscord(text, {
+      repoRoot: "C:\\Users\\dev\\.disclaw\\workspaces\\agent-x",
+      home: "C:\\Users\\dev",
+    });
+    expect(result).toBe("File at <disclaw>\\src\\main.ts");
+  });
+
+  // Mixed slash styles (common on Windows when tools output forward slashes)
+  it("replaces forward-slash variants of Windows paths", () => {
+    const text = "File at C:/Users/dev/.disclaw/workspaces/agent-x/src/main.ts";
+    const result = sanitizeForDiscord(text, {
+      repoRoot: "C:\\Users\\dev\\.disclaw\\workspaces\\agent-x",
+      home: "C:\\Users\\dev",
+    });
+    expect(result).toBe("File at <disclaw>/src/main.ts");
+  });
+});