Merge ticket/022-edit-existing-metric-declarations

webapp/src/lib/api.ts

@@ -205,6 +205,28 @@ async function postJson<T>(path: string, body: unknown): Promise<T> {
   return res.json() as Promise<T>
 }
 
+// Same error handling as `postJson` (throws `ApiError` with the parsed message) but for a PUT — used where updating in place, rather than creating, is the operation.
+async function putJson<T>(path: string, body: unknown): Promise<T> {
+  const res = await fetch(path, {
+    method: 'PUT',
+    headers: { 'Content-Type': 'application/json' },
+    body: JSON.stringify(body),
+  })
+  if (!res.ok) {
+    let message = `${path} failed: ${res.status}`
+    try {
+      const errorBody = (await res.json()) as Partial<ApiErrorBody>
+      if (errorBody && typeof errorBody.error === 'string') {
+        message = errorBody.error
+      }
+    } catch {
+      // response body wasn't JSON; fall back to the generic message
+    }
+    throw new ApiError(message)
+  }
+  return res.json() as Promise<T>
+}
+
 async function sendJson<T>(path: string, method: string, body?: unknown): Promise<T> {
   const res = await fetch(path, {
     method,
@@ -275,6 +297,11 @@ export function declareMetric(request: MetricDeclaration): Promise<MetricDeclara
   return postJson('/api/metrics', request)
 }
 
+// Updates the metric declaration named `existingName` in place (`existingName` may differ from `request.name` to rename it), rather than declaring a second metric or failing on a duplicate-name conflict.
+export function updateMetric(existingName: string, request: MetricDeclaration): Promise<MetricDeclaration> {
+  return putJson(`/api/metrics/${encodeURIComponent(existingName)}`, request)
+}
+
 export function fetchMetricBucketValues(
   name: string,
   params: {