add prometheus service widget

src/widgets/prometheus/component.jsx

@@ -0,0 +1,38 @@
+import { useTranslation } from "next-i18next";
+
+import Container from "components/services/widget/container";
+import Block from "components/services/widget/block";
+import useWidgetAPI from "utils/proxy/use-widget-api";
+
+export default function Component({ service }) {
+  const { t } = useTranslation();
+
+  const { widget } = service;
+  const { data: targetsData, error: targetsError } = useWidgetAPI(widget, "targets");
+
+  if (targetsError) {
+    return <Container error={targetsError} />;
+  }
+
+  if (!targetsData) {
+    return (
+      <Container service={service}>
+        <Block label="prometheus.targets_up" />
+        <Block label="prometheus.targets_down" />
+        <Block label="prometheus.targets_total" />
+      </Container>
+    );
+  }
+
+  const upCount = targetsData.data.activeTargets.filter(a => a.health === "up").length;
+  const downCount = targetsData.data.activeTargets.filter(a => a.health === "down").length;
+  const totalCount = targetsData.data.activeTargets.length;
+
+  return (
+    <Container service={service}>
+      <Block label="prometheus.targets_up" value={t("common.number", { value: upCount })} />
+      <Block label="prometheus.targets_down" value={t("common.number", { value: downCount })} />
+      <Block label="prometheus.targets_total" value={t("common.number", { value: totalCount })} />
+    </Container>
+  );
+}

src/widgets/prometheus/widget.js

@@ -0,0 +1,14 @@
+import genericProxyHandler from "utils/proxy/handlers/generic";
+
+const widget = {
+  api: "{url}/api/v1/{endpoint}",
+  proxyHandler: genericProxyHandler,
+
+  mappings: {
+    targets: {
+      endpoint: "targets"
+    },
+  },
+};
+
+export default widget;