#434

frontend/src/lib/api.ts

@@ -199,3 +199,28 @@ export const apiDelete = async <T = void> (
 
 export const isApiError = <T = unknown> (err: unknown): err is AxiosError<T> =>
     axios.isAxiosError (err)
+
+
+// Native downloads let the browser stream to disk without buffering a Blob in app memory.
+export const apiDownload = async (
+    path: string,
+    body: Record<string, string>,
+    locale: LocaleCode,
+): Promise<void> => {
+  const token = await csrfToken ()
+  const form = document.createElement ('form')
+  form.method = 'post'
+  form.action = `${API_BASE_URL}${path}?${new URLSearchParams ({ locale })}`
+  form.hidden = true
+  for (const [name, value] of Object.entries ({ ...body, authenticity_token: token }))
+  {
+    const input = document.createElement ('input')
+    input.type = 'hidden'
+    input.name = name
+    input.value = value
+    form.append (input)
+  }
+  document.body.append (form)
+  form.submit ()
+  form.remove ()
+}