Add tests for write-path error handling and packaging bugs

package.json

@@ -26,7 +26,7 @@
     "prepublishOnly": "npm run clean && npm run build",
     "pretest": "npm run build",
     "test": "vitest run",
-    "test:integration": "INFLUX_TEST_ENABLED=true vitest run tests/integration.test.ts",
+    "test:integration": "INFLUX_TEST_ENABLED=true vitest run integration",
     "test:watch": "vitest",
     "test:infra:up": "docker compose -f docker-compose.test.yml up -d --wait",
     "test:infra:down": "docker compose -f docker-compose.test.yml down",

tests/README.md

@@ -0,0 +1,50 @@
+# Test suite
+
+Run `npm run build` first — tests spawn the compiled `build/index.js`.
+
+| Command                    | Runs                                                               |
+| -------------------------- | ------------------------------------------------------------------ |
+| `npm test`                 | Everything; live-instance tests self-skip                          |
+| `npm run test:integration` | Every file matching `integration`, with `INFLUX_TEST_ENABLED=true` |
+
+## Conventions
+
+Three kinds of test live here, distinguished by how they are marked.
+
+**Active** — asserts what the code does today and must keep doing. Green.
+
+**`describe.skip("[P<n>] …")`** — acceptance criteria for a planned change that
+has not landed. Skipped so CI stays green, but each one fails against current
+code, so un-skipping is all that is needed to drive the work. Where an
+acceptance test has a paired active test asserting the opposite, the pair is
+deliberate: the active test goes red when the fix lands, which forces the stale
+characterization to be deleted rather than left behind. Two acceptance tests are
+no-regression guards that pass both before and after, and say so in a comment.
+
+**`it.todo(…)`** — a test that cannot be written yet because the answer it would
+assert against is unknown. Each names the question ID and what unblocks it.
+These appear in every vitest run, so the open list stays visible in CI output.
+
+## Coverage for the write-path error and packaging fixes
+
+| Bug                                             | Tests                                                   |
+| ----------------------------------------------- | ------------------------------------------------------- |
+| Write path drops the InfluxDB error body        | `write-error-core.test.ts`, `write-error-cloud.test.ts` |
+| Which endpoint each product type writes to      | `write-routing.test.ts`                                 |
+| `zod` is a runtime dependency, declared as dev  | `packaging.test.ts`                                     |
+| `ping()` version/build header passthrough       | `base-connection-ping.test.ts`                          |
+| `write_line_protocol` contract, error surfacing | `protocol-write.test.ts`                                |
+
+None of these are version-gated — they're bugs in the current server,
+independent of which InfluxDB release is on the other end.
+
+## Live-instance gates
+
+`INFLUX_TEST_ENABLED` covers any live instance; tests under it must pass on the
+CI Core container.
+
+```bash
+npm run test:infra:up
+source env.test.example && npm run test:integration
+npm run test:infra:down
+```

tests/base-connection-ping.test.ts

@@ -0,0 +1,85 @@
+/**
+ * `ping()` — version/build header parsing.
+ *
+ * The `x-influxdb-version` and `x-influxdb-build` response headers are fetched
+ * but never parsed, compared, or otherwise used. This pins the current
+ * passthrough behavior, independent of any specific InfluxDB version.
+ */
+
+import { describe, it, expect, vi, afterEach } from "vitest";
+import { BaseConnectionService } from "../src/services/base-connection.service.js";
+import { InfluxProductType } from "../src/helpers/enums/influx-product-types.enum.js";
+import type { McpServerConfig } from "../src/config.js";
+
+const TOKEN = "test-token-not-used";
+
+function configFor(type: InfluxProductType): McpServerConfig {
+  return {
+    influx: {
+      url: "http://localhost:19999/",
+      token: TOKEN,
+      type,
+      cluster_id:
+        type === InfluxProductType.CloudDedicated
+          ? "00000000-0000-0000-0000-000000000000"
+          : undefined,
+    },
+    server: { name: "influxdb-mcp-server", version: "test" },
+    tools: { profile: "operator" },
+  };
+}
+
+/** Stub `fetch` with a success response and return the recorded calls. */
+function stubFetchOk(headers: Record<string, string> = {}) {
+  const fetchMock = vi.fn().mockResolvedValue({
+    ok: true,
+    status: 200,
+    headers: { get: (name: string) => headers[name.toLowerCase()] ?? null },
+    json: async () => ({ status: "pass" }),
+  });
+  vi.stubGlobal("fetch", fetchMock);
+  return fetchMock;
+}
+
+afterEach(() => {
+  vi.unstubAllGlobals();
+});
+
+describe("ping – version reporting, current behavior", () => {
+  it("returns the x-influxdb-version header unparsed", async () => {
+    const fetchMock = stubFetchOk({
+      "x-influxdb-version": "3.11.0-0.rc.1",
+      "x-influxdb-build": "Enterprise",
+    });
+
+    const result = await new BaseConnectionService(
+      configFor(InfluxProductType.Enterprise),
+    ).ping();
+
+    expect(fetchMock).toHaveBeenCalled();
+    expect(result).toEqual({
+      ok: true,
+      version: "3.11.0-0.rc.1",
+      build: "Enterprise",
+    });
+  });
+
+  it('reports build "Other" when only a version header is present', async () => {
+    stubFetchOk({ "x-influxdb-version": "3.11.0" });
+
+    const result = await new BaseConnectionService(
+      configFor(InfluxProductType.Core),
+    ).ping();
+
+    expect(result).toEqual({ ok: true, version: "3.11.0", build: "Other" });
+  });
+
+  it("reports no version at all when the header is absent", async () => {
+    stubFetchOk();
+    const result = await new BaseConnectionService(
+      configFor(InfluxProductType.Enterprise),
+    ).ping();
+
+    expect(result).toEqual({ ok: true, version: undefined, build: undefined });
+  });
+});

tests/fixtures/write-errors.ts

@@ -0,0 +1,220 @@
+/**
+ * Write-path error fixtures.
+ *
+ * Companion to `error-responses.ts`, which covers the query path. Shapes follow
+ * the same two families:
+ *
+ *   Axios errors (Core/Enterprise/Clustered HTTP paths)
+ *     error.response.status, error.response.statusText, error.response.data
+ *   SDK HttpError (Cloud Dedicated/Serverless client paths)
+ *     error.statusCode, error.statusMessage, error.body, error.json, error.message
+ *
+ * ── Provenance ──────────────────────────────────────────────────────────────
+ *
+ * RECORDED   Body text observed against a real instance, or carried over from
+ *            `error-responses.ts`.
+ * PROVISIONAL Body text is a placeholder pending live verification. Tests
+ *            using these fixtures must assert on structure and on substrings
+ *            the fixture itself defines (`DUPLICATED_TAG_KEY`), never on
+ *            exact InfluxDB wording, so that correcting the fixture does not
+ *            invalidate the assertion.
+ *
+ * The duplicate-tag-key response shape is resolved: verified 2026-07-28
+ * against both an Enterprise instance (`--upgrade-pacha-tree`, 3.11.0-0.rc.1)
+ * and a Core instance (3.11.0-nightly) — identical response on both. See
+ * `CORE_400_DUPLICATE_TAG_UNDER_PARTIAL_DATA` below.
+ *
+ * Whether a stopped node makes `write_lp` return 503 (instead of the current
+ * 400) remains unverified — needs a live instance with a node stopped
+ * mid-write. See `CORE_503_NODE_STOPPED` below.
+ */
+
+import type { AxiosErrorShape, SdkErrorShape } from "./error-responses.js";
+
+export type { AxiosErrorShape, SdkErrorShape };
+
+// ── The 3.11 duplicate-tag-key case ─────────────────────────────────────────
+//
+// 3.11 rejects a line carrying the same tag key twice up front, the same way
+// duplicate field keys were already refused. The rejection needs to reach the
+// model naming the duplicated tag, not just as a generic "bad request."
+
+/**
+ * Line protocol that 3.11 rejects: the same tag key appears twice.
+ *
+ * A one-letter tag key (e.g. `m,t=a,t=a f=1i`) is not usable in an assertion —
+ * `not.toContain("t")` matches ordinary English in the generic error string
+ * and passes for the wrong reason — so the fixture uses a distinctive key
+ * instead. The condition under test is identical.
+ */
+export const DUPLICATE_TAG_LINE = "m,region=east,region=west f=1i";
+
+/** The tag key duplicated in {@link DUPLICATE_TAG_LINE}. */
+export const DUPLICATED_TAG_KEY = "region";
+
+/**
+ * RECORDED — duplicated tag named only inside the partial-write
+ * `data[].error_message` structure.
+ *
+ * Verified 2026-07-28 against both Core (3.11.0-nightly) and Enterprise
+ * (3.11.0-0.rc.1, `--upgrade-pacha-tree`) — identical on both. `data.error`
+ * resolves to the generic "partial write of line protocol occurred" and the
+ * actionable detail is one level down, under `data[].error_message`. The MCP
+ * server sends `accept_partial=true` on the Core/Enterprise v3 path, so this
+ * is the shape a real rejection takes; resolving `data.error` alone is not
+ * sufficient. `original_line` is truncated by InfluxDB itself, mid tag value —
+ * not something our code does.
+ */
+export const CORE_400_DUPLICATE_TAG_UNDER_PARTIAL_DATA: AxiosErrorShape = {
+  response: {
+    status: 400,
+    statusText: "Bad Request",
+    data: {
+      error: "partial write of line protocol occurred",
+      data: [
+        {
+          error_message: `invalid line protocol - multiple instances of '${DUPLICATED_TAG_KEY}' tag found`,
+          line_number: 1,
+          original_line: "m,region=east,region",
+        },
+      ],
+    },
+  },
+  message: "Request failed with status code 400",
+};
+
+// ── Status arms that currently discard the body ─────────────────────────────
+
+/** RECORDED — Core rejects an unauthenticated request with this exact text. */
+export const CORE_401_UNAUTHENTICATED: AxiosErrorShape = {
+  response: {
+    status: 401,
+    statusText: "Unauthorized",
+    data: { error: "the request was not authenticated" },
+  },
+  message: "Request failed with status code 401",
+};
+
+/** PROVISIONAL — permission-scoped token refused by the write endpoint. */
+export const CORE_403_UNAUTHORIZED: AxiosErrorShape = {
+  response: {
+    status: 403,
+    statusText: "Forbidden",
+    data: { error: "the request was not authorized" },
+  },
+  message: "Request failed with status code 403",
+};
+
+/** PROVISIONAL — body exceeds the configured limit. Plain-text body. */
+export const CORE_413_PAYLOAD_TOO_LARGE: AxiosErrorShape = {
+  response: {
+    status: 413,
+    statusText: "Payload Too Large",
+    data: "the request body was too large: limit is 10485760 bytes",
+  },
+  message: "Request failed with status code 413",
+};
+
+/** PROVISIONAL — line protocol parsed but semantically rejected. */
+export const CORE_422_UNPROCESSABLE: AxiosErrorShape = {
+  response: {
+    status: 422,
+    statusText: "Unprocessable Entity",
+    data: {
+      error:
+        "invalid column type for column 'value', expected iox::column_type::field::float, got iox::column_type::field::string",
+    },
+  },
+  message: "Request failed with status code 422",
+};
+
+// ── 503 — the status neither handler has an arm for ─────────────────────────
+
+/**
+ * PROVISIONAL — a stopped node.
+ *
+ * InfluxDB 3.11's release notes (Core/Enterprise-scoped) document a 400→503
+ * change for the legacy `/api/v2/write` endpoint that Core/Enterprise also
+ * expose for backward compatibility — not the `/api/v3/write_lp` endpoint
+ * this server actually calls for those product types. Whether
+ * `/api/v3/write_lp` behaves the same on a stopped node is unverified,
+ * answerable only on a live instance with a node stopped mid-write. The
+ * fixture exists so the handler's 503 arm is testable either way — the arm is
+ * also needed for the separate `Clustered` product (InfluxDB Clustered, the
+ * self-hosted sibling to Cloud Dedicated — not a multi-node Enterprise
+ * deployment), which does call `/api/v2/write` (see `write-routing.test.ts`).
+ * That's unrelated to these Core/Enterprise release notes: `Clustered` is a
+ * different product on its own release train.
+ */
+export const CORE_503_NODE_STOPPED: AxiosErrorShape = {
+  response: {
+    status: 503,
+    statusText: "Service Unavailable",
+    data: { error: "node is stopped and not accepting writes" },
+  },
+  message: "Request failed with status code 503",
+};
+
+// ── Object-body fallback ────────────────────────────────────────────────────
+
+/**
+ * RECORDED shape, unhandled status.
+ *
+ * Any status with no arm falls through to a fallback that interpolates
+ * `error.response.data` directly. When the body is parsed JSON — the normal
+ * case — the model receives `[object Object]`.
+ */
+export const CORE_500_OBJECT_BODY: AxiosErrorShape = {
+  response: {
+    status: 500,
+    statusText: "Internal Server Error",
+    data: { error: "internal error while persisting write" },
+  },
+  message: "Request failed with status code 500",
+};
+
+/** RECORDED shape — plain-text body on an unhandled status, which does survive. */
+export const CORE_500_STRING_BODY: AxiosErrorShape = {
+  response: {
+    status: 500,
+    statusText: "Internal Server Error",
+    data: "internal error while persisting write",
+  },
+  message: "Request failed with status code 500",
+};
+
+// ── Cloud SDK (HttpError) write failures ────────────────────────────────────
+//
+// `@influxdata/influxdb3-client` throws `HttpError`, which carries `statusCode`
+// rather than `response.status`. Every status branch in the write handler tests
+// `error.response?.status` and therefore misses on these entirely.
+
+/** PROVISIONAL — Cloud rejection of {@link DUPLICATE_TAG_LINE}. */
+export const CLOUD_SDK_400_DUPLICATE_TAG: SdkErrorShape = {
+  statusCode: 400,
+  statusMessage: "Bad Request",
+  body: `{"code":"invalid","message":"invalid line protocol: duplicate tag key '${DUPLICATED_TAG_KEY}' on line 1"}`,
+  json: {
+    code: "invalid",
+    message: `invalid line protocol: duplicate tag key '${DUPLICATED_TAG_KEY}' on line 1`,
+  },
+  message: `invalid line protocol: duplicate tag key '${DUPLICATED_TAG_KEY}' on line 1`,
+};
+
+/** RECORDED shape — Cloud rejects an invalid token. */
+export const CLOUD_SDK_401_UNAUTHORIZED: SdkErrorShape = {
+  statusCode: 401,
+  statusMessage: "Unauthorized",
+  body: '{"code":"unauthorized","message":"unauthorized access"}',
+  json: { code: "unauthorized", message: "unauthorized access" },
+  message: "unauthorized access",
+};
+
+/** PROVISIONAL — Cloud write rejected while a node is unavailable. */
+export const CLOUD_SDK_503_UNAVAILABLE: SdkErrorShape = {
+  statusCode: 503,
+  statusMessage: "Service Unavailable",
+  body: '{"code":"unavailable","message":"service temporarily unavailable"}',
+  json: { code: "unavailable", message: "service temporarily unavailable" },
+  message: "service temporarily unavailable",
+};