Throttle getAddressFromCoords

package.json

@@ -5,14 +5,14 @@
   "repository": "ReactTraining/react-workshop",
   "homepage": "https://reacttraining.com",
   "license": "GPL-3.0",
-  "authors": ["Ryan Florence", "Michael Jackson"],
+  "authors": [
+    "Ryan Florence",
+    "Michael Jackson"
+  ],
   "scripts": {
-    "start":
-      "node ./scripts/build.js && webpack-dev-server --inline --content-base subjects",
-    "server-exercise":
-      "supervisor -- -r babel-register subjects/ServerRendering/exercise/server.js",
-    "server-solution":
-      "supervisor -- -r babel-register subjects/ServerRendering/solution/server.js",
+    "start": "node ./scripts/build.js && webpack-dev-server --inline --content-base subjects",
+    "server-exercise": "supervisor -- -r babel-register subjects/ServerRendering/exercise/server.js",
+    "server-solution": "supervisor -- -r babel-register subjects/ServerRendering/solution/server.js",
     "start-api": "node api.js"
   },
   "dependencies": {
@@ -30,7 +30,6 @@
     "bootstrap": "^3.3.4",
     "bootstrap-webpack": "0.0.5",
     "css-loader": "^0.23.1",
-    "debounce-promise": "^3.0.1",
     "events": "^1.0.2",
     "expect": "^1.13.4",
     "exports-loader": "^0.6.3",

subjects/RenderProps/utils/getAddressFromCoords.js

@@ -1,21 +1,35 @@
-import debounce from "debounce-promise"
-
 const GoogleMapsAPI = "https://maps.googleapis.com/maps/api"
 
-const unthrottledGetAddressFromCoords = (latitude, longitude) => {
-  const url = `${GoogleMapsAPI}/geocode/json?latlng=${latitude},${
-    longitude
-  }`
+const getAddressFromCoords = (latitude, longitude) => {
+  const url = `${GoogleMapsAPI}/geocode/json?latlng=${latitude},${longitude}`
 
   return fetch(url)
     .then(res => res.json())
     .then(json => json.results[0].formatted_address)
 }
 
-// Throttle requests to once per second
-const getAddressFromCoords = debounce(
-  unthrottledGetAddressFromCoords,
-  1000
-)
+const maxCallsPerMinute = 20
+let lastCallTime = 0
+let lastWarningTime = 0
+let promise = Promise.resolve()
+
+const throttledGetAddressFromCoords = (latitude, longitude) => {
+  const currentTime = Date.now()
+  const requiredWaitTime = 60000 / maxCallsPerMinute
+
+  if (lastCallTime + requiredWaitTime < currentTime) {
+    lastCallTime = currentTime
+    promise = getAddressFromCoords(latitude, longitude)
+  } else if (currentTime - lastWarningTime > 5000) {
+    lastWarningTime = currentTime
+    window.alert(
+      "It looks like you're calling getAddressFromCoords many times " +
+        "quickly in a loop. Take a closer look at the componentDidUpdate " +
+        "function in <GeoAddress>..."
+    )
+  }
+
+  return promise
+}
 
-export default getAddressFromCoords
+export default throttledGetAddressFromCoords