Feature: customapi info widget (#7168)

docs/widgets/info/customapi.md

@@ -0,0 +1,36 @@
+---
+title: Custom API
+description: Custom API Information Widget Configuration
+---
+
+_(Find the Custom API service widget [here](../services/customapi.md))_
+
+The Custom API information widget shows values from a custom self-hosted or third party API in your Homepage header, alongside an icon.
+
+```yaml
+- customapi:
+    url: http://custom.api.host.or.ip:port/path/to/exact/api/endpoint
+    icon: mdi-api # optional, see below
+    label: My API # optional, shown below the values
+    href: https://custom.api.host # optional, makes the widget a link
+    refreshInterval: 10000 # optional - in milliseconds, defaults to 10s
+    username: username # auth - optional
+    password: password # auth - optional
+    method: GET # optional, e.g. POST
+    headers: # optional, must be object
+      X-API-Token: token
+    requestBody: # optional, can be string or object
+    mappings:
+      - field: key
+        label: Field 1
+      - field: path.to.key2
+        label: Field 2
+        format: number # optional - defaults to text
+      - field: path.to.key3
+        label: Field 3
+        format: percent
+```
+
+The `icon` accepts the same values as [service icons](../../configs/services.md#icons), e.g. `mdi-api`, `si-github`, `sh-homepage`, a dashboard icon name like `homepage.png`, or a full URL. If no icon is set, a generic API icon is shown.
+
+Mappings support the same `field`, `format`, `remap`, `scale`, `prefix` and `suffix` options as the [Custom API service widget](../services/customapi.md). The `additionalField` option and the `display` modes are not supported.

docs/widgets/info/index.md

@@ -7,6 +7,7 @@ search:
 
 You can also find a list of all available info widgets in the sidebar navigation.
 
+- [Custom API](customapi.md)
 - [Date & Time](datetime.md)
 - [Glances](glances.md)
 - [Greeting](greeting.md)

docs/widgets/services/customapi.md

@@ -3,6 +3,8 @@ title: Custom API
 description: Custom Widget Configuration from the API
 ---
 
+_(Find the Custom API information widget [here](../info/customapi.md))_
+
 This widget can show information from custom self-hosted or third party API.
 
 Fields need to be defined in the `mappings` section YAML object to correlate with the value in the APIs JSON object. Final field definition needs to be the key with the desired value information.

mkdocs.yml

@@ -194,6 +194,7 @@ nav:
           - widgets/services/zabbix.md
       - "Information Widgets":
           - widgets/info/index.md
+          - widgets/info/customapi.md
           - widgets/info/datetime.md
           - widgets/info/glances.md
           - widgets/info/greeting.md

src/__tests__/pages/api/widgets/customapi.test.js

@@ -0,0 +1,118 @@
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+import createMockRes from "test-utils/create-mock-res";
+
+const { getPrivateWidgetOptions, httpProxy, logger } = vi.hoisted(() => ({
+  getPrivateWidgetOptions: vi.fn(),
+  httpProxy: vi.fn(),
+  logger: { debug: vi.fn() },
+}));
+
+vi.mock("utils/config/widget-helpers", () => ({
+  getPrivateWidgetOptions,
+}));
+
+vi.mock("utils/proxy/http", () => ({
+  httpProxy,
+}));
+
+vi.mock("utils/logger", () => ({
+  default: () => logger,
+}));
+
+import handler from "pages/api/widgets/customapi";
+
+const json = (body) => Buffer.from(JSON.stringify(body));
+
+async function callRoute(options, index = "0") {
+  getPrivateWidgetOptions.mockResolvedValueOnce(options);
+  const res = createMockRes();
+  await handler({ query: { index } }, res);
+  return res;
+}
+
+describe("pages/api/widgets/customapi", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it.each([
+    ["no widget at that index", undefined],
+    ["a widget without a url", { method: "GET" }],
+    ["an invalid url", { url: "api.local/data" }],
+  ])("returns 400 without calling upstream for %s", async (_, options) => {
+    const res = await callRoute(options, "3");
+
+    expect(getPrivateWidgetOptions).toHaveBeenCalledWith("customapi", "3");
+    expect(res.statusCode).toBe(400);
+    expect(httpProxy).not.toHaveBeenCalled();
+  });
+
+  it("proxies an authenticated POST with custom headers and a JSON body", async () => {
+    httpProxy.mockResolvedValueOnce([200, "application/json", json({ json: { hello: "world" } })]);
+
+    const res = await callRoute({
+      url: "https://httpbin.org/post",
+      username: "admin",
+      password: "hunter2",
+      method: "POST",
+      headers: { "X-Secret-Token": "super-secret", "Content-Type": "application/json" },
+      requestBody: { hello: "world" },
+    });
+
+    expect(httpProxy).toHaveBeenCalledWith(new URL("https://httpbin.org/post"), {
+      method: "POST",
+      headers: {
+        "User-Agent": "homepage",
+        Accept: "application/json",
+        "X-Secret-Token": "super-secret",
+        "Content-Type": "application/json",
+        Authorization: `Basic ${Buffer.from("admin:hunter2").toString("base64")}`,
+      },
+      body: '{"hello":"world"}',
+    });
+    expect(res.statusCode).toBe(200);
+    expect(res.body).toEqual({ json: { hello: "world" } });
+  });
+
+  it("sends a string body as-is and lets config override default headers", async () => {
+    httpProxy.mockResolvedValueOnce([200, "application/json", json({ data: { viewer: { login: "shamoon" } } })]);
+    const query = '{"query":"{ viewer { login } }"}';
+
+    const res = await callRoute({
+      url: "https://api.github.com/graphql",
+      method: "POST",
+      headers: { Authorization: "Bearer ghp_token", "User-Agent": "my-dashboard" },
+      requestBody: query,
+    });
+
+    expect(httpProxy).toHaveBeenCalledWith(expect.any(URL), {
+      method: "POST",
+      headers: { "User-Agent": "my-dashboard", Accept: "application/json", Authorization: "Bearer ghp_token" },
+      body: query,
+    });
+    expect(res.body).toEqual({ data: { viewer: { login: "shamoon" } } });
+  });
+
+  it.each([
+    ["an HTTP error", [403, "application/json", json({ message: "API rate limit exceeded for 1.2.3.4" })]],
+    [
+      "a network failure",
+      [500, "application/json", { error: { message: "connect ECONNREFUSED", rawError: { address: "10.0.0.5" } } }],
+    ],
+    ["a non-JSON response", [200, "text/html", Buffer.from("<html><body>Login</body></html>")]],
+  ])("returns only a sanitized error for %s", async (_, upstream) => {
+    httpProxy.mockResolvedValueOnce(upstream);
+
+    const res = await callRoute({ url: "https://api.github.com/repos/gethomepage/homepage?token=abc" });
+
+    expect(httpProxy).toHaveBeenCalledWith(expect.any(URL), {
+      method: "GET",
+      headers: { "User-Agent": "homepage", Accept: "application/json" },
+    });
+    expect(res.statusCode).toBe(upstream[0] === 200 ? 500 : upstream[0]);
+    expect(res.body.error.url).toBe("api.github.com (see logs for details)");
+    expect(JSON.stringify(res.body)).not.toMatch(/rate limit|ECONNREFUSED|10\.0\.0\.5|<html>|token=abc/);
+    expect(res.setHeader).not.toHaveBeenCalled();
+  });
+});

src/components/widgets/customapi/customapi.jsx

@@ -0,0 +1,53 @@
+import classNames from "classnames";
+import { useTranslation } from "next-i18next/pages";
+import { TbApi } from "react-icons/tb";
+import useSWR from "swr";
+
+import Container from "../widget/container";
+import Error from "../widget/error";
+import Raw from "../widget/raw";
+import WidgetLabel from "../widget/widget_label";
+
+import ResolvedIcon from "components/resolvedicon";
+import { formatValue, getValue } from "widgets/customapi/utils";
+
+export default function CustomApi({ options }) {
+  const { t } = useTranslation();
+
+  const { index, icon, label, mappings = [], refreshInterval = 10000 } = options;
+
+  const { data, error } = useSWR(`/api/widgets/customapi?${new URLSearchParams({ index }).toString()}`, {
+    refreshInterval: Math.max(1000, refreshInterval),
+  });
+
+  if (error || (data?.error && !mappings.some((mapping) => mapping.field === "error"))) {
+    return <Error options={options} />;
+  }
+
+  return (
+    <Container options={options} additionalClassNames="information-widget-customapi">
+      <Raw>
+        <div className="flex flex-row items-center">
+          <div className="flex-none mr-2">
+            {icon ? (
+              <ResolvedIcon icon={icon} width={24} height={24} />
+            ) : (
+              <TbApi className="w-6 h-6 text-theme-800 dark:text-theme-200" />
+            )}
+          </div>
+          <div className={classNames("flex flex-wrap items-center gap-0.5", !data && "animate-pulse")}>
+            {mappings.map((mapping) => (
+              <div key={mapping.label} className="flex flex-col items-center justify-center px-1 text-xs">
+                <span className="text-theme-800 dark:text-theme-200">{mapping.label}</span>
+                <span className="text-theme-800/70 dark:text-theme-200/50">
+                  {data ? formatValue(t, mapping, getValue(mapping.field, data)) : "-"}
+                </span>
+              </div>
+            ))}
+          </div>
+        </div>
+        {label && <WidgetLabel label={label} />}
+      </Raw>
+    </Container>
+  );
+}

src/components/widgets/customapi/customapi.test.jsx

@@ -0,0 +1,117 @@
+// @vitest-environment jsdom
+
+import { screen } from "@testing-library/react";
+import { beforeEach, describe, expect, it, vi } from "vitest";
+
+import { renderWithProviders } from "test-utils/render-with-providers";
+
+const { useSWR } = vi.hoisted(() => ({ useSWR: vi.fn() }));
+vi.mock("swr", () => ({ default: useSWR }));
+
+vi.mock("components/resolvedicon", () => ({
+  default: ({ icon }) => <div data-testid="resolved-icon" data-icon={icon} />,
+}));
+
+import CustomApi from "./customapi";
+
+const settings = { settings: { target: "_self" } };
+
+describe("components/widgets/customapi", () => {
+  beforeEach(() => {
+    vi.clearAllMocks();
+  });
+
+  it("shows GitHub repo stats once loaded, with the fallback icon and a label", () => {
+    const options = {
+      index: 6,
+      label: "Homepage",
+      refreshInterval: 300000,
+      mappings: [
+        { field: "stargazers_count", label: "Stars", format: "number" },
+        { field: "open_issues_count", label: "Open", format: "number" },
+        { field: "forks_count", label: "Forks", format: "number" },
+      ],
+    };
+
+    useSWR.mockReturnValue({ data: undefined, error: undefined });
+    const { container, rerender } = renderWithProviders(<CustomApi options={options} />, settings);
+
+    expect(useSWR).toHaveBeenCalledWith("/api/widgets/customapi?index=6", { refreshInterval: 300000 });
+    expect(screen.getAllByText("-")).toHaveLength(3);
+    expect(screen.queryByTestId("resolved-icon")).toBeNull();
+    expect(container.querySelector("svg")).not.toBeNull();
+
+    useSWR.mockReturnValue({
+      data: { stargazers_count: 32809, open_issues_count: 1, forks_count: 2127, owner: { login: "gethomepage" } },
+      error: undefined,
+    });
+    rerender(<CustomApi options={options} />);
+
+    expect(screen.queryByText("-")).toBeNull();
+    expect(screen.getByText("Stars").nextSibling).toHaveTextContent("32809");
+    expect(screen.getByText("Open").nextSibling).toHaveTextContent("1");
+    expect(screen.getByText("Forks").nextSibling).toHaveTextContent("2127");
+    expect(screen.getByText("Homepage")).toHaveClass("information-widget-label");
+  });
+
+  it("shows a nested weather value with a configured icon and suffix", () => {
+    useSWR.mockReturnValue({
+      data: { current: { time: "2026-09-22T20:15", temperature_2m: 7.8, wind_speed_10m: 12.4 } },
+      error: undefined,
+    });
+
+    renderWithProviders(
+      <CustomApi
+        options={{
+          index: 7,
+          icon: "mdi-thermometer",
+          mappings: [{ field: "current.temperature_2m", label: "Temp", format: "float", suffix: "°C" }],
+        }}
+      />,
+      settings,
+    );
+
+    expect(useSWR).toHaveBeenCalledWith("/api/widgets/customapi?index=7", { refreshInterval: 10000 });
+    expect(screen.getByTestId("resolved-icon")).toHaveAttribute("data-icon", "mdi-thermometer");
+    expect(screen.getByText("7.8 °C")).toBeInTheDocument();
+  });
+
+  it("shows a status API's error field as data when it is mapped", () => {
+    useSWR.mockReturnValue({ data: { error: "E_NONE", pending: 3 }, error: undefined });
+
+    renderWithProviders(
+      <CustomApi
+        options={{
+          index: 0,
+          mappings: [
+            { field: "error", label: "Status", remap: [{ value: "E_NONE", to: "OK" }] },
+            { field: "pending", label: "Queue", format: "number" },
+          ],
+        }}
+      />,
+      settings,
+    );
+
+    expect(screen.queryByText("widget.api_error")).toBeNull();
+    expect(screen.getByText("OK")).toBeInTheDocument();
+    expect(screen.getByText("3")).toBeInTheDocument();
+  });
+
+  it("shows the error state when the upstream API fails, clamping a too-fast refresh", () => {
+    useSWR.mockReturnValue({
+      data: { error: { message: "HTTP Error", url: "api.github.com (see logs for details)" } },
+      error: undefined,
+    });
+
+    renderWithProviders(
+      <CustomApi
+        options={{ index: 6, refreshInterval: 500, mappings: [{ field: "stargazers_count", label: "Stars" }] }}
+      />,
+      settings,
+    );
+
+    expect(useSWR).toHaveBeenCalledWith("/api/widgets/customapi?index=6", { refreshInterval: 1000 });
+    expect(screen.getByText("widget.api_error")).toBeInTheDocument();
+    expect(screen.queryByText("Stars")).toBeNull();
+  });
+});

src/components/widgets/widget.jsx

@@ -16,6 +16,7 @@ const widgetMappings = {
   longhorn: dynamic(() => import("components/widgets/longhorn/longhorn")),
   kubernetes: dynamic(() => import("components/widgets/kubernetes/kubernetes")),
   stocks: dynamic(() => import("components/widgets/stocks/stocks")),
+  customapi: dynamic(() => import("components/widgets/customapi/customapi")),
 };
 
 export default function Widget({ widget, style }) {

src/pages/api/widgets/customapi.js

@@ -0,0 +1,46 @@
+import { getPrivateWidgetOptions } from "utils/config/widget-helpers";
+import createLogger from "utils/logger";
+import { sanitizeErrorURL } from "utils/proxy/api-helpers";
+import { httpProxy } from "utils/proxy/http";
+
+const logger = createLogger("customapi");
+
+export default async function handler(req, res) {
+  const { index } = req.query;
+
+  const options = await getPrivateWidgetOptions("customapi", index);
+
+  if (!options?.url) {
+    return res.status(400).json({ error: "Missing Custom API URL" });
+  }
+
+  let url;
+  try {
+    url = new URL(options.url);
+  } catch {
+    return res.status(400).json({ error: "Invalid Custom API URL" });
+  }
+
+  const headers = { "User-Agent": "homepage", Accept: "application/json", ...(options.headers ?? {}) };
+  if (options.username && options.password) {
+    headers.Authorization = `Basic ${Buffer.from(`${options.username}:${options.password}`).toString("base64")}`;
+  }
+
+  const params = { method: options.method ?? "GET", headers };
+  if (options.requestBody) {
+    params.body = typeof options.requestBody === "object" ? JSON.stringify(options.requestBody) : options.requestBody;
+  }
+
+  const [status, , data] = await httpProxy(url, params);
+
+  if (status >= 400) {
+    logger.debug("HTTP Error %d calling %s//%s%s", status, url.protocol, url.host, url.pathname);
+    return res.status(status).json({ error: { message: "HTTP Error", url: sanitizeErrorURL(url) } });
+  }
+
+  try {
+    return res.status(status).json(JSON.parse(Buffer.from(data).toString()));
+  } catch {
+    return res.status(500).json({ error: { message: "Invalid JSON", url: sanitizeErrorURL(url) } });
+  }
+}

src/test-utils/render-with-providers.jsx

@@ -9,5 +9,7 @@ export function renderWithProviders(ui, { settings = {} } = {}) {
     setSettings: () => {},
   };
 
-  return render(<SettingsContext.Provider value={value}>{ui}</SettingsContext.Provider>);
+  const wrapper = ({ children }) => <SettingsContext.Provider value={value}>{children}</SettingsContext.Provider>;
+
+  return render(ui, { wrapper });
 }

src/utils/config/widget-helpers.js

@@ -31,7 +31,7 @@ export async function cleanWidgetGroups(widgets) {
     const optionKeys = Object.keys(sanitizedOptions);
 
     // delete private options from the sanitized options
-    ["username", "password", "key", "apiKey"].forEach((pO) => {
+    ["username", "password", "key", "apiKey", "headers", "requestBody", "method"].forEach((pO) => {
       if (optionKeys.includes(pO)) {
         delete sanitizedOptions[pO];
       }
@@ -57,7 +57,7 @@ export async function getPrivateWidgetOptions(type, widgetIndex) {
 
   const privateOptions =
     widgets.map((widget) => {
-      const { index, url, username, password, key, apiKey } = widget.options;
+      const { index, url, username, password, key, apiKey, headers, requestBody, method } = widget.options;
 
       return {
         type: widget.type,
@@ -68,6 +68,9 @@ export async function getPrivateWidgetOptions(type, widgetIndex) {
           password,
           key,
           apiKey,
+          headers,
+          requestBody,
+          method,
         },
       };
     }) || {};

src/utils/config/widget-helpers.test.js

@@ -60,6 +60,17 @@ describe("utils/config/widget-helpers", () => {
     expect(cleaned[2].options.apiKey).toBeUndefined();
   });
 
+  it("cleanWidgetGroups removes customapi request options", async () => {
+    const cleaned = await cleanWidgetGroups([
+      {
+        type: "customapi",
+        options: { index: 0, url: "http://x", headers: { a: "b" }, requestBody: "body", method: "POST", icon: "mdi-x" },
+      },
+    ]);
+
+    expect(cleaned[0].options).toEqual({ index: 0, icon: "mdi-x" });
+  });
+
   it("getPrivateWidgetOptions returns private options for a specific widget", async () => {
     fs.readFile.mockResolvedValueOnce("ignored");
     yaml.load.mockReturnValueOnce([{ search: { url: "http://x", username: "u", password: "p", key: "k" } }]);

src/widgets/customapi/component.jsx

@@ -1,161 +1,13 @@
 import classNames from "classnames";
 import { useTranslation } from "next-i18next/pages";
 
+import { formatValue, getColor, getValue } from "./utils";
+
 import Block from "components/services/widget/block";
 import Container from "components/services/widget/container";
 import * as shvl from "utils/config/shvl";
 import useWidgetAPI from "utils/proxy/use-widget-api";
 
-function getValue(field, data) {
-  let value = data;
-  let lastField = field;
-  let key = "";
-
-  // Support APIs that return arrays or scalars directly.
-  if (typeof field === "undefined") {
-    return value;
-  }
-
-  // shvl is easier, everything else is kept for backwards compatibility.
-  if (typeof field === "string") {
-    return shvl.get(data, field, null) ?? data[field] ?? null;
-  }
-
-  while (typeof lastField === "object") {
-    key = Object.keys(lastField)[0] ?? null;
-
-    if (key === null) {
-      break;
-    }
-
-    value = value[key];
-    lastField = lastField[key];
-  }
-
-  if (typeof value === "undefined") {
-    return null;
-  }
-
-  return value[lastField] ?? null;
-}
-
-function getSize(data) {
-  if (Array.isArray(data) || typeof data === "string") {
-    return data.length;
-  } else if (typeof data === "object" && data !== null) {
-    return Object.keys(data).length;
-  }
-
-  return NaN;
-}
-
-function formatValue(t, mapping, rawValue) {
-  let value = rawValue;
-
-  // Remap the value.
-  const remaps = mapping?.remap ?? [];
-  for (let i = 0; i < remaps.length; i += 1) {
-    const remap = remaps[i];
-    if (remap?.any || remap?.value === value) {
-      value = remap.to;
-      break;
-    }
-  }
-
-  // Scale the value. Accepts either a number to multiply by or a string
-  // like "12/345".
-  const scale = mapping?.scale;
-  if (typeof scale === "number") {
-    value *= scale;
-  } else if (typeof scale === "string") {
-    const parts = scale.split("/");
-    const numerator = parts[0] ? parseFloat(parts[0]) : 1;
-    const denominator = parts[1] ? parseFloat(parts[1]) : 1;
-    value = (value * numerator) / denominator;
-  }
-
-  // Format the value using a known type.
-  switch (mapping?.format) {
-    case "number":
-      value = t("common.number", { value: parseInt(value, 10) });
-      break;
-    case "float":
-      value = t("common.number", { value });
-      break;
-    case "percent":
-      value = t("common.percent", { value });
-      break;
-    case "duration":
-      value = t("common.duration", { value });
-      break;
-    case "bytes":
-      value = t("common.bytes", { value });
-      break;
-    case "bitrate":
-      value = t("common.bitrate", { value });
-      break;
-    case "date":
-      value = t("common.date", {
-        value,
-        lng: mapping?.locale,
-        dateStyle: mapping?.dateStyle ?? "long",
-        timeStyle: mapping?.timeStyle,
-      });
-      break;
-    case "relativeDate":
-      value = t("common.relativeDate", {
-        value,
-        lng: mapping?.locale,
-        style: mapping?.style,
-        numeric: mapping?.numeric,
-      });
-      break;
-    case "size":
-      value = t("common.number", { value: getSize(value) });
-      break;
-    case "text":
-    default:
-    // nothing
-  }
-
-  // Apply fixed prefix.
-  const prefix = mapping?.prefix;
-  if (prefix) {
-    value = `${prefix} ${value}`;
-  }
-
-  // Apply fixed suffix.
-  const suffix = mapping?.suffix;
-  if (suffix) {
-    value = `${value} ${suffix}`;
-  }
-
-  return value;
-}
-
-function getColor(mapping, customData) {
-  const value = getValue(mapping.additionalField.field, customData);
-  const { color } = mapping.additionalField;
-
-  switch (color) {
-    case "adaptive":
-      try {
-        const number = parseFloat(value);
-        return number > 0 ? "text-emerald-300" : "text-rose-300";
-      } catch (e) {
-        return "";
-      }
-    case "black":
-      return `text-black`;
-    case "white":
-      return `text-white`;
-    case "theme":
-      return `text-theme-500`;
-    default:
-      return "";
-  }
-}
-
 export default function Component({ service }) {
   const { t } = useTranslation();
 

src/widgets/customapi/utils.js

@@ -0,0 +1,151 @@
+import * as shvl from "utils/config/shvl";
+
+export function getValue(field, data) {
+  let value = data;
+  let lastField = field;
+  let key = "";
+
+  // Support APIs that return arrays or scalars directly.
+  if (typeof field === "undefined") {
+    return value;
+  }
+
+  // shvl is easier, everything else is kept for backwards compatibility.
+  if (typeof field === "string") {
+    return shvl.get(data, field, null) ?? data[field] ?? null;
+  }
+
+  while (typeof lastField === "object") {
+    key = Object.keys(lastField)[0] ?? null;
+
+    if (key === null) {
+      break;
+    }
+
+    value = value[key];
+    lastField = lastField[key];
+  }
+
+  if (typeof value === "undefined") {
+    return null;
+  }
+
+  return value[lastField] ?? null;
+}
+
+export function getSize(data) {
+  if (Array.isArray(data) || typeof data === "string") {
+    return data.length;
+  } else if (typeof data === "object" && data !== null) {
+    return Object.keys(data).length;
+  }
+
+  return NaN;
+}
+
+export function formatValue(t, mapping, rawValue) {
+  let value = rawValue;
+
+  // Remap the value.
+  const remaps = mapping?.remap ?? [];
+  for (let i = 0; i < remaps.length; i += 1) {
+    const remap = remaps[i];
+    if (remap?.any || remap?.value === value) {
+      value = remap.to;
+      break;
+    }
+  }
+
+  // Scale the value. Accepts either a number to multiply by or a string
+  // like "12/345".
+  const scale = mapping?.scale;
+  if (typeof scale === "number") {
+    value *= scale;
+  } else if (typeof scale === "string") {
+    const parts = scale.split("/");
+    const numerator = parts[0] ? parseFloat(parts[0]) : 1;
+    const denominator = parts[1] ? parseFloat(parts[1]) : 1;
+    value = (value * numerator) / denominator;
+  }
+
+  // Format the value using a known type.
+  switch (mapping?.format) {
+    case "number":
+      value = t("common.number", { value: parseInt(value, 10) });
+      break;
+    case "float":
+      value = t("common.number", { value });
+      break;
+    case "percent":
+      value = t("common.percent", { value });
+      break;
+    case "duration":
+      value = t("common.duration", { value });
+      break;
+    case "bytes":
+      value = t("common.bytes", { value });
+      break;
+    case "bitrate":
+      value = t("common.bitrate", { value });
+      break;
+    case "date":
+      value = t("common.date", {
+        value,
+        lng: mapping?.locale,
+        dateStyle: mapping?.dateStyle ?? "long",
+        timeStyle: mapping?.timeStyle,
+      });
+      break;
+    case "relativeDate":
+      value = t("common.relativeDate", {
+        value,
+        lng: mapping?.locale,
+        style: mapping?.style,
+        numeric: mapping?.numeric,
+      });
+      break;
+    case "size":
+      value = t("common.number", { value: getSize(value) });
+      break;
+    case "text":
+    default:
+    // nothing
+  }
+
+  // Apply fixed prefix.
+  const prefix = mapping?.prefix;
+  if (prefix) {
+    value = `${prefix} ${value}`;
+  }
+
+  // Apply fixed suffix.
+  const suffix = mapping?.suffix;
+  if (suffix) {
+    value = `${value} ${suffix}`;
+  }
+
+  return value;
+}
+
+export function getColor(mapping, customData) {
+  const value = getValue(mapping.additionalField.field, customData);
+  const { color } = mapping.additionalField;
+
+  switch (color) {
+    case "adaptive":
+      try {
+        const number = parseFloat(value);
+        return number > 0 ? "text-emerald-300" : "text-rose-300";
+      } catch (e) {
+        return "";
+      }
+    case "black":
+      return `text-black`;
+    case "white":
+      return `text-white`;
+    case "theme":
+      return `text-theme-500`;
+    default:
+      return "";
+  }
+}

src/widgets/customapi/utils.test.js

@@ -0,0 +1,82 @@
+import { describe, expect, it } from "vitest";
+
+import { formatValue, getColor, getSize, getValue } from "./utils";
+
+const t = (key, { value }) => `${key.replace("common.", "")}:${value}`;
+
+const data = {
+  status: "online",
+  stats: { cpu: 12.5, change: -1.2, users: ["a", "b"] },
+  "dotted.key": 7,
+};
+
+describe("widgets/customapi/utils", () => {
+  it.each([
+    ["the root when no field is set", undefined, data],
+    ["a dotted path", "stats.cpu", 12.5],
+    ["a literal key containing a dot", "dotted.key", 7],
+    ["null for a missing path", "stats.missing", null],
+    ["a legacy object path", { stats: "cpu" }, 12.5],
+    ["null for a legacy path through a missing key", { missing: "cpu" }, null],
+    ["null for an empty legacy path", {}, null],
+  ])("getValue returns %s", (_, field, expected) => {
+    expect(getValue(field, data)).toEqual(expected);
+  });
+
+  it.each([
+    [["a", "b", "c"], 3],
+    ["abcd", 4],
+    [{ a: 1, b: 2 }, 2],
+    [null, NaN],
+    [5, NaN],
+  ])("getSize(%j) is %s", (input, expected) => {
+    expect(getSize(input)).toEqual(expected);
+  });
+
+  it.each([
+    [{}, "raw", "raw"],
+    [{ format: "number" }, "42.9", "number:42"],
+    [{ format: "float" }, 4.2, "number:4.2"],
+    [{ format: "percent", scale: 100 }, 0.25, "percent:25"],
+    [{ format: "duration" }, 90, "duration:90"],
+    [{ format: "bytes", scale: "1024/1" }, 2, "bytes:2048"],
+    [{ format: "bitrate", scale: "/8" }, 800, "bitrate:100"],
+    [{ format: "date" }, "2026-09-22", "date:2026-09-22"],
+    [{ format: "relativeDate" }, "2026-09-22", "relativeDate:2026-09-22"],
+    [{ format: "size" }, ["a", "b"], "number:2"],
+    [
+      {
+        remap: [
+          { value: 0, to: "Off" },
+          { value: 1, to: "On" },
+        ],
+      },
+      1,
+      "On",
+    ],
+    [
+      {
+        remap: [
+          { value: "ok", to: "Healthy" },
+          { any: true, to: "Unknown" },
+        ],
+      },
+      "degraded",
+      "Unknown",
+    ],
+    [{ format: "number", prefix: "$", suffix: "USD" }, 10, "$ number:10 USD"],
+  ])("formatValue with %j formats %j as %j", (mapping, raw, expected) => {
+    expect(formatValue(t, mapping, raw)).toBe(expected);
+  });
+
+  it.each([
+    ["adaptive", "stats.cpu", "text-emerald-300"],
+    ["adaptive", "stats.change", "text-rose-300"],
+    ["black", "stats.cpu", "text-black"],
+    ["white", "stats.cpu", "text-white"],
+    ["theme", "stats.cpu", "text-theme-500"],
+    [undefined, "stats.cpu", ""],
+  ])("getColor %s for %s is %j", (color, field, expected) => {
+    expect(getColor({ additionalField: { field, color } }, data)).toBe(expected);
+  });
+});