fix(monitor): use global console channel and implement shard filtering (#87)

This PR fixes the issue where console monitoring was empty when a specific shard was targeted on the official Screeps server.

### Changes:
- **Unified Subscription**: Changed WebSocket subscription path from `shard/console` (invalid) to the global `console` channel.
- **Shard Filtering**: Implemented client-side filtering in `handleConsoleEvent` to only display logs matching the targeted shard.
- **Precise Timing**: Retained the shard-specific `api.time()` call for accurate tick duration tracking.
- **Tests**: Added and updated 48 unit tests verifying the fix and shard filtering logic.
- **Distribution**: Rebuilt `dist/index.js` and bumped version to `v0.2.1`.

Reviewed-on: #87

__tests__/monitor.test.js

@@ -11,12 +11,15 @@ vi.mock("@actions/core", () => ({
   endGroup: vi.fn(),
 }));
 
-// ── mock @actions/artifact so tests never attempt real uploads ──────────────
-vi.mock("@actions/artifact", () => ({
-  DefaultArtifactClient: vi.fn().mockImplementation(() => ({
+import * as artifact from "@actions/artifact";
+vi.mock("@actions/artifact", () => {
+  const mockClient = {
     uploadArtifact: vi.fn().mockResolvedValue({}),
-  })),
-}));
+  };
+  return {
+    create: vi.fn(() => mockClient),
+  };
+});
 
 import * as core from "@actions/core";
 import fs from "fs";
@@ -28,8 +31,10 @@ import {
   buildSubscribePath,
   detectTraceback,
   detectWarning,
+  outputMultiline,
   buildProgressMessage,
   writeLogFile,
+  uploadLogArtifacts,
   handleConsoleEvent,
   monitorConsole,
 } from "../monitor.js";
@@ -53,20 +58,20 @@ describe("isOfficialServer", () => {
 });
 
 describe("buildSubscribePath", () => {
-  it("returns shard0/console for official server (no shard provided)", () => {
-    expect(buildSubscribePath("screeps.com")).toBe("shard0/console");
+  it("returns console for official server (no shard provided)", () => {
+    expect(buildSubscribePath("screeps.com")).toBe("console");
   });
 
   it("returns console for private server (no shard provided)", () => {
     expect(buildSubscribePath("builder64")).toBe("console");
   });
 
-  it("returns <shard>/console when shard is provided (official)", () => {
-    expect(buildSubscribePath("screeps.com", "shard3")).toBe("shard3/console");
+  it("returns console when shard is provided (official)", () => {
+    expect(buildSubscribePath("screeps.com", "shard3")).toBe("console");
   });
 
-  it("returns <shard>/console when shard is provided (private)", () => {
-    expect(buildSubscribePath("builder64", "myshard")).toBe("myshard/console");
+  it("returns console when shard is provided (private)", () => {
+    expect(buildSubscribePath("builder64", "myshard")).toBe("console");
   });
 });
 
@@ -123,6 +128,33 @@ describe("detectWarning", () => {
   });
 });
 
+describe("outputMultiline", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("prefixes lines with shard when provided", () => {
+    outputMultiline("line1\nline2", "info", "shard0");
+    expect(core.info).toHaveBeenCalledWith("[shard0] line1");
+    expect(core.info).toHaveBeenCalledWith("[shard0] line2");
+  });
+
+  it("does not prefix when shard is missing", () => {
+    outputMultiline("line1", "info");
+    expect(core.info).toHaveBeenCalledWith("line1");
+  });
+
+  it("uses core.warning for level=warning", () => {
+    outputMultiline("warn", "warning", "s0");
+    expect(core.warning).toHaveBeenCalledWith("[s0] warn");
+  });
+
+  it("uses core.error for level=error", () => {
+    outputMultiline("err", "error", "s0");
+    expect(core.error).toHaveBeenCalledWith("[s0] err");
+  });
+});
+
 describe("buildProgressMessage", () => {
   it("formats correctly at 0 elapsed", () => {
     expect(buildProgressMessage(0, 50)).toBe("[Monitor] 0/50 ticks elapsed...");
@@ -141,48 +173,79 @@ describe("buildProgressMessage", () => {
   });
 });
 
+describe("uploadLogArtifacts", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("instantiates client and calls uploadArtifact", async () => {
+    await uploadLogArtifacts(
+      ["/path/to/shard0_console_log.txt"],
+      "custom-name",
+    );
+    expect(artifact.create().uploadArtifact).toHaveBeenCalledWith(
+      "custom-name",
+      ["/path/to/shard0_console_log.txt"],
+      "/path/to",
+      { continueOnError: true },
+    );
+  });
+
+  it("does nothing if filePaths is empty", async () => {
+    await uploadLogArtifacts([]);
+    expect(artifact.create().uploadArtifact).not.toHaveBeenCalled();
+  });
+});
+
 // ────────────────────────────────────────────────────────────────────────────
 // handleConsoleEvent
 // ────────────────────────────────────────────────────────────────────────────
 
 describe("handleConsoleEvent", () => {
   let state;
-  let stdoutBuffer;
+  let shardBuffers;
 
   beforeEach(() => {
     vi.clearAllMocks();
     state = { sawTraceback: false, sawErrorLog: false, sawWarningLog: false };
-    stdoutBuffer = [];
+    shardBuffers = {};
   });
 
   const makeEvent = (log = [], results = [], error = null) => ({
     data: { messages: { log, results }, error },
   });
 
-  it("calls core.info for each stdout line when logToFile=false", () => {
-    const event = makeEvent(["line1", "line2"]);
-    handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state);
-    expect(core.info).toHaveBeenCalledWith("line1");
-    expect(core.info).toHaveBeenCalledWith("line2");
-    expect(stdoutBuffer).toHaveLength(0);
+  it("calls core.info for each stdout line with shard prefix when logToFile=false", () => {
+    const event = {
+      data: {
+        shard: "shard0",
+        messages: { log: ["line1"], results: ["line2"] },
+      },
+    };
+    handleConsoleEvent(event, { logToFile: false }, shardBuffers, state);
+    expect(core.info).toHaveBeenCalledWith("[shard0] line1");
+    expect(core.info).toHaveBeenCalledWith("[shard0] line2");
+    expect(Object.keys(shardBuffers)).toHaveLength(0);
   });
 
   it("buffers stdout when logToFile=true; does not call core.info", () => {
-    const event = makeEvent(["line1", "line2"]);
-    handleConsoleEvent(event, { logToFile: true }, stdoutBuffer, state);
+    const event = {
+      data: { shard: "shard0", messages: { log: ["line1", "line2"] } },
+    };
+    handleConsoleEvent(event, { logToFile: true }, shardBuffers, state);
     expect(core.info).not.toHaveBeenCalled();
-    expect(stdoutBuffer).toEqual(["line1", "line2"]);
+    expect(shardBuffers["shard0"]).toEqual(["line1", "line2"]);
   });
 
   it("includes results lines in output", () => {
     const event = makeEvent([], ["result1"]);
-    handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state);
+    handleConsoleEvent(event, { logToFile: false }, shardBuffers, state);
     expect(core.info).toHaveBeenCalledWith("result1");
   });
 
   it("calls core.error when error field is non-empty", () => {
     const event = makeEvent([], [], "Script crashed");
-    handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state);
+    handleConsoleEvent(event, { logToFile: false }, shardBuffers, state);
     expect(core.error).toHaveBeenCalledWith("Script crashed");
     expect(state.sawErrorLog).toBe(true);
   });
@@ -190,44 +253,74 @@ describe("handleConsoleEvent", () => {
   it("sets state.sawTraceback when error contains stack frames", () => {
     const error = "TypeError: boom\n    at Object.<anonymous> (main:1:1)";
     const event = makeEvent([], [], error);
-    handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state);
+    handleConsoleEvent(event, { logToFile: false }, shardBuffers, state);
     expect(state.sawTraceback).toBe(true);
     expect(state.sawErrorLog).toBe(true);
   });
 
   it("does not set sawTraceback for plain error without stack frames", () => {
     const event = makeEvent([], [], "Script error: low CPU");
-    handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state);
+    handleConsoleEvent(event, { logToFile: false }, shardBuffers, state);
     expect(state.sawTraceback).toBe(false);
     expect(state.sawErrorLog).toBe(true);
   });
 
   it("sets state.sawWarningLog and calls core.warning for warn lines", () => {
     const event = makeEvent(["<font color='orange'>low energy</font>"]);
-    handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state);
+    handleConsoleEvent(event, { logToFile: false }, shardBuffers, state);
     expect(state.sawWarningLog).toBe(true);
     expect(core.warning).toHaveBeenCalled();
   });
 
   it("calls core.warning regardless of logToFile setting", () => {
     const event = makeEvent(["<font color='orange'>warn line</font>"]);
-    handleConsoleEvent(event, { logToFile: true }, stdoutBuffer, state);
+    handleConsoleEvent(event, { logToFile: true }, shardBuffers, state);
     expect(core.warning).toHaveBeenCalled();
   });
 
   it("handles missing messages gracefully (no crash on empty event)", () => {
     const event = { data: {} };
     expect(() =>
-      handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state),
+      handleConsoleEvent(event, { logToFile: false }, shardBuffers, state),
     ).not.toThrow();
   });
 
   it("handles completely empty event gracefully", () => {
     const event = {};
     expect(() =>
-      handleConsoleEvent(event, { logToFile: false }, stdoutBuffer, state),
+      handleConsoleEvent(event, { logToFile: false }, shardBuffers, state),
     ).not.toThrow();
   });
+
+  it("filters messages by shard when targetShard is provided", () => {
+    const event = { data: { shard: "shard0", messages: { log: ["msg0"] } } };
+    handleConsoleEvent(event, { shard: "shard1" }, shardBuffers, state);
+    expect(core.info).not.toHaveBeenCalled();
+
+    handleConsoleEvent(event, { shard: "shard0" }, shardBuffers, state);
+    expect(core.info).toHaveBeenCalledWith("[shard0] msg0");
+  });
+
+  it("does not filter when targetShard is undefined", () => {
+    const event = { data: { shard: "shard0", messages: { log: ["msg0"] } } };
+    handleConsoleEvent(event, {}, shardBuffers, state);
+    expect(core.info).toHaveBeenCalledWith("[shard0] msg0");
+  });
+
+  it("buffers messages separately for different shards", () => {
+    const event0 = { data: { shard: "shard0", messages: { log: ["msg0"] } } };
+    const event1 = { data: { shard: "shard1", messages: { log: ["msg1"] } } };
+    handleConsoleEvent(event0, { logToFile: true }, shardBuffers, state);
+    handleConsoleEvent(event1, { logToFile: true }, shardBuffers, state);
+    expect(shardBuffers["shard0"]).toEqual(["msg0"]);
+    expect(shardBuffers["shard1"]).toEqual(["msg1"]);
+  });
+
+  it("uses 'default' key when shard is missing in event", () => {
+    const event = { data: { messages: { log: ["msg"] } } };
+    handleConsoleEvent(event, { logToFile: true }, shardBuffers, state);
+    expect(shardBuffers["default"]).toEqual(["msg"]);
+  });
 });
 
 // ────────────────────────────────────────────────────────────────────────────
@@ -357,19 +450,19 @@ describe("monitorConsole", () => {
     );
   });
 
-  it("subscribes to 'shard0/console' for the official server (default)", async () => {
+  it("subscribes to 'console' for the official server (default)", async () => {
     const api = buildMockApi({
       hostname: "screeps.com",
       ticks: [100, 101, 102, 103],
     });
     await monitorConsole(api, { ...BASE_OPTS, hostname: "screeps.com" });
     expect(api.socket.subscribe).toHaveBeenCalledWith(
-      "shard0/console",
+      "console",
       expect.any(Function),
     );
   });
 
-  it("subscribes to custom shard when provided", async () => {
+  it("subscribes to 'console' even when custom shard is provided", async () => {
     const api = buildMockApi({
       hostname: "screeps.com",
       ticks: [100, 101, 102, 103],
@@ -380,10 +473,10 @@ describe("monitorConsole", () => {
       shard: "shard3",
     });
     expect(api.socket.subscribe).toHaveBeenCalledWith(
-      "shard3/console",
+      "console",
       expect.any(Function),
     );
-    // Verify polling also uses shard3
+    // Verify polling still uses shard3 for timing
     expect(api.time).toHaveBeenCalledWith("shard3");
   });
 
@@ -504,4 +597,37 @@ describe("monitorConsole", () => {
     expect(result.sawTraceback).toBe(true);
     expect(result.sawErrorLog).toBe(true);
   });
+
+  it("creates separate log files for different shards when logToFile=true", async () => {
+    const api = buildMockApi({ ticks: [100, 101, 102, 103] });
+
+    setTimeout(() => {
+      api._fireConsole({
+        shard: "shard0",
+        messages: { log: ["msg0"], results: [] },
+        error: null,
+      });
+      api._fireConsole({
+        shard: "shard1",
+        messages: { log: ["msg1"], results: [] },
+        error: null,
+      });
+    }, 50);
+
+    // Verify uploadArtifact was called with two files
+    await monitorConsole(api, {
+      ...BASE_OPTS,
+      logToFile: true,
+    });
+
+    expect(artifact.create().uploadArtifact).toHaveBeenCalledWith(
+      "screeps-console-log",
+      expect.arrayContaining([
+        expect.stringContaining("shard0_console_log.txt"),
+        expect.stringContaining("shard1_console_log.txt"),
+      ]),
+      expect.any(String),
+      { continueOnError: true },
+    );
+  });
 });

index.js

@@ -197,7 +197,7 @@ export async function postCode() {
       });
   }
 
-  // ── Console monitoring (optional) ────────────────────────────────────────
+  // Console monitoring (optional)
   const monitorTicks = parseInt(core.getInput("monitor") || "0", 10);
   if (monitorTicks > 0) {
     const result = await monitorConsole(api, {

monitor.js

@@ -1,13 +1,9 @@
 import * as core from "@actions/core";
-import { DefaultArtifactClient } from "@actions/artifact";
+import { create } from "@actions/artifact";
 import fs from "fs";
 import path from "path";
 import os from "os";
 
-// ────────────────────────────────────────────────────────────────────────────
-// Shard / subscribe-path helpers
-// ────────────────────────────────────────────────────────────────────────────
-
 /**
  * Returns true if the hostname is the official Screeps server.
  * Used to decide whether to prefix the subscribe path with a shard name.
@@ -33,14 +29,11 @@ export function isOfficialServer(hostname) {
  * @returns {string}
  */
 export function buildSubscribePath(hostname, shard) {
-  if (shard) return `${shard}/console`;
-  return isOfficialServer(hostname) ? "shard0/console" : "console";
+  // The console channel on Screeps official and most private servers is 'console'.
+  // We subscribe to the aggregate feed and filter by shard in handleConsoleEvent.
+  return "console";
 }
 
-// ────────────────────────────────────────────────────────────────────────────
-// Detection helpers
-// ────────────────────────────────────────────────────────────────────────────
-
 /**
  * Returns true when errorText contains JavaScript stack-frame lines.
  * Screeps places runtime errors (including stack traces) in event.data.error.
@@ -76,17 +69,42 @@ export function detectWarning(logLines) {
  * @returns {string}
  */
 export function safeDecode(text) {
-  if (typeof text !== "string" || !text.includes("%")) return text;
+  if (typeof text !== "string") return text;
+  let result = text;
+  if (result.includes("%")) {
     try {
-    return decodeURIComponent(text);
+      result = decodeURIComponent(result);
     } catch (err) {
-    return text;
+      // Ignore decoding errors
     }
   }
+  // Screeps console often contains HTML entities
+  return result
+    .replace(/&lt;/g, "<")
+    .replace(/&gt;/g, ">")
+    .replace(/&quot;/g, '"')
+    .replace(/&amp;/g, "&");
+}
 
-// ────────────────────────────────────────────────────────────────────────────
-// Output helpers
-// ────────────────────────────────────────────────────────────────────────────
+/**
+ * Outputs text to the action log, splitting by newline to ensure proper display.
+ * Optionally prepends a [shard] prefix.
+ *
+ * @param {string} text
+ * @param {"info"|"warning"|"error"} level
+ * @param {string} [shard]
+ */
+export function outputMultiline(text, level = "info", shard = null) {
+  if (!text) return;
+  const prefix = shard ? `[${shard}] ` : "";
+  const lines = text.split(/\r?\n/);
+  lines.forEach((line) => {
+    const formattedLine = `${prefix}${line}`;
+    if (level === "error") core.error(formattedLine);
+    else if (level === "warning") core.warning(formattedLine);
+    else core.info(formattedLine);
+  });
+}
 
 /**
  * Builds a CI-friendly progress string for core.info().
@@ -99,10 +117,6 @@ export function buildProgressMessage(elapsed, total) {
   return `[Monitor] ${elapsed}/${total} ticks elapsed...`;
 }
 
-// ────────────────────────────────────────────────────────────────────────────
-// File / artifact helpers
-// ────────────────────────────────────────────────────────────────────────────
-
 /**
  * Writes an array of log lines to a UTF-8 text file, one line per entry.
  *
@@ -115,37 +129,33 @@ export async function writeLogFile(lines, filePath) {
 }
 
 /**
- * Uploads a file as a named workflow artifact using @actions/artifact.
+ * Uploads one or more files as a named workflow artifact using @actions/artifact.
  * Degrades gracefully to core.warning() if the runner does not support the
- * artifact service (e.g. a bare self-hosted runner without the service configured).
+ * artifact service.
  *
- * @param {string} filePath      - Absolute path of the file to upload
+ * @param {string[]} filePaths   - Absolute paths of the files to upload
  * @param {string}   [artifactName="screeps-console-log"] - Artifact display name
  * @returns {Promise<void>}
  */
-export async function uploadLogArtifact(
-  filePath,
+export async function uploadLogArtifacts(
+  filePaths,
   artifactName = "screeps-console-log",
 ) {
+  if (!filePaths || filePaths.length === 0) return;
   try {
-    const client = new DefaultArtifactClient();
-    await client.uploadArtifact(
-      artifactName,
-      [filePath],
-      path.dirname(filePath),
-    );
-    core.info(`[Monitor] Console log uploaded as artifact '${artifactName}'.`);
+    const client = create();
+    const rootDir = path.dirname(filePaths[0]);
+    await client.uploadArtifact(artifactName, filePaths, rootDir, {
+      continueOnError: true,
+    });
+    core.info(`[Monitor] Console logs uploaded as artifact '${artifactName}'.`);
   } catch (err) {
     core.warning(
-      `[Monitor] Could not upload console log as artifact: ${err.message}`,
+      `[Monitor] Could not upload console logs as artifact: ${err.message}`,
     );
   }
 }
 
-// ────────────────────────────────────────────────────────────────────────────
-// Console event handler
-// ────────────────────────────────────────────────────────────────────────────
-
 /**
  * Processes a single 'console' WebSocket event from the Screeps socket.
  * Mutates `state` and `stdoutBuffer` in place; never throws.
@@ -167,58 +177,63 @@ export async function uploadLogArtifact(
  *   - All stdout lines → core.info() when logToFile=false,
  *                        pushed to stdoutBuffer when logToFile=true.
  *
- * @param {{ data?: { messages?: { log?: string[], results?: string[] }, error?: string } }} event
- * @param {{ logToFile: boolean }} opts
- * @param {string[]} stdoutBuffer - Mutable buffer used in logToFile mode
+ * @param {{ data?: { messages?: { log?: string[], results?: string[] }, error?: string, shard?: string } }} event
+ * @param {{ logToFile: boolean, shard?: string }} opts
+ * @param {Record<string, string[]>} shardBuffers - Mutable buffer Map used in logToFile mode
  * @param {{ sawTraceback: boolean, sawErrorLog: boolean, sawWarningLog: boolean }} state
  */
-export function handleConsoleEvent(event, opts, stdoutBuffer, state) {
-  const { logToFile } = opts;
+export function handleConsoleEvent(event, opts, shardBuffers, state) {
+  const { logToFile, shard: targetShard } = opts;
   const data = event?.data ?? {};
+
+  // Shard filtering: If a shard is specified in opts, only process messages from that shard.
+  // Official server events include a 'shard' property in event.data.
+  if (targetShard && data.shard && data.shard !== targetShard) {
+    return;
+  }
+
   const logLines = data?.messages?.log ?? [];
   const results = data?.messages?.results ?? [];
   const errorText = data?.error ?? null;
 
-  // ── Warn detection (always live regardless of logToFile) ─────────────────
+  // Warn detection (always live regardless of logToFile)
   if (detectWarning(logLines)) {
     state.sawWarningLog = true;
     const warnPattern = /<font\s+color=['"](?:orange|yellow)['"]/i;
     logLines
       .filter((l) => warnPattern.test(l))
-      .forEach((l) => core.warning(safeDecode(l)));
+      .forEach((l) => outputMultiline(safeDecode(l), "warning", data.shard));
   }
 
-  // ── Traceback detection in log lines (Screeps sometimes sends errors here) ─
+  // Traceback detection in log lines (Screeps sometimes sends errors here)
   if (logLines.some((l) => detectTraceback(l))) {
     state.sawTraceback = true;
     state.sawErrorLog = true;
   }
 
-  // ── Stdout lines ──────────────────────────────────────────────────────────
+  // Stdout lines
   const allStdout = [...logLines, ...results].map(safeDecode);
   if (allStdout.length > 0) {
     if (logToFile) {
-      stdoutBuffer.push(...allStdout);
+      const shard = data.shard || "default";
+      if (!shardBuffers[shard]) shardBuffers[shard] = [];
+      shardBuffers[shard].push(...allStdout);
     } else {
-      allStdout.forEach((l) => core.info(l));
+      allStdout.forEach((l) => outputMultiline(l, "info", data.shard));
     }
   }
 
-  // ── Error field (always live) ─────────────────────────────────────────────
+  // Error field (always live)
   if (errorText) {
     state.sawErrorLog = true;
     const decodedError = safeDecode(errorText);
-    core.error(decodedError);
+    outputMultiline(decodedError, "error", data.shard);
     if (detectTraceback(decodedError)) {
       state.sawTraceback = true;
     }
   }
 }
 
-// ────────────────────────────────────────────────────────────────────────────
-// Tick polling
-// ────────────────────────────────────────────────────────────────────────────
-
 /**
  * Sleeps for the given number of milliseconds.
  *
@@ -262,10 +277,6 @@ export async function pollUntilDone(
   return elapsed;
 }
 
-// ────────────────────────────────────────────────────────────────────────────
-// Main orchestrator
-// ────────────────────────────────────────────────────────────────────────────
-
 /**
  * @typedef {Object} MonitorOptions
  * @property {number}  monitor         - Number of game ticks to collect.
@@ -317,7 +328,7 @@ export async function monitorConsole(api, opts) {
   const subscribePath = buildSubscribePath(hostname, providedShard);
 
   // Shared mutable state — updated by handleConsoleEvent via event listener
-  const stdoutBuffer = [];
+  const shardBuffers = {}; // { [shardName]: string[] }
   const state = {
     sawTraceback: false,
     sawErrorLog: false,
@@ -325,13 +336,13 @@ export async function monitorConsole(api, opts) {
   };
   let lastProgressTick = 0;
 
-  // ── Step 1: record starting tick ─────────────────────────────────────────
+  // Step 1: record starting tick
   const { time: startTick } = await api.time(shard);
 
-  // ── Step 2: connect socket + subscribe ───────────────────────────────────
+  // Step 2: connect socket + subscribe
   await api.socket.connect();
   await api.socket.subscribe(subscribePath, (event) => {
-    handleConsoleEvent(event, opts, stdoutBuffer, state);
+    handleConsoleEvent(event, opts, shardBuffers, state);
   });
 
   core.info(
@@ -340,7 +351,7 @@ export async function monitorConsole(api, opts) {
       "...",
   );
 
-  // ── Step 3 & 4: tick-poll loop ───────────────────────────────────────────
+  // Step 3 & 4: tick-poll loop
   try {
     await pollUntilDone(
       api,
@@ -368,15 +379,29 @@ export async function monitorConsole(api, opts) {
       },
     );
   } finally {
-    // ── Step 5: always disconnect cleanly ────────────────────────────────
+    // Step 5: always disconnect cleanly
     api.socket.disconnect();
   }
 
-  // ── Step 6: artifact upload ───────────────────────────────────────────────
-  if (logToFile && stdoutBuffer.length > 0) {
-    const tmpFile = path.join(os.tmpdir(), "screeps_console_log.txt");
-    await writeLogFile(stdoutBuffer, tmpFile);
-    await uploadLogArtifact(tmpFile);
+  // Step 6: artifact upload
+  const shardKeys = Object.keys(shardBuffers);
+  if (logToFile && shardKeys.length > 0) {
+    const tmpDir = await fs.promises.mkdtemp(
+      path.join(os.tmpdir(), "screeps-monitor-"),
+    );
+    const filePaths = [];
+
+    for (const sName of shardKeys) {
+      const fileName =
+        sName === "default"
+          ? "screeps_console_log.txt"
+          : `${sName}_console_log.txt`;
+      const tmpFile = path.join(tmpDir, fileName);
+      await writeLogFile(shardBuffers[sName], tmpFile);
+      filePaths.push(tmpFile);
+    }
+
+    await uploadLogArtifacts(filePaths);
   } else if (logToFile) {
     core.info(
       "[Monitor] No stdout lines were collected; skipping artifact upload.",

package.json

@@ -1,7 +1,7 @@
 {
   "name": "screeps-deploy-action",
-  "version": "0.2.0",
-  "description": "Deploys screeps code to the official game or an pirvate server.",
+  "version": "0.2.1",
+  "description": "Deploys screeps code to the official game or a private server.",
   "type": "module",
   "main": "index.js",
   "scripts": {
@@ -10,6 +10,7 @@
     "build": "ncc build index.js -o dist -m --external utf-8-validate --external bufferutil"
   },
   "dependencies": {
+    "@actions/artifact": "^1.1.2",
     "@actions/core": "^3.0.0",
     "glob": "^13.0.0",
     "screeps-api": "^1.7.2"