EDIT: It seems that I'm hitting the query limit, but I'm not being returned a full 200 results. So upon further research it looks like the Google API will let me query 10 boxes, return those results, and then smacks me with an OVER_QUERY_LIMIT status for the rest. So I figure I now have two options: slow my queries, or broaden my distance to create fewer boxes along the route.
I'm currently fooling around building a little web app that provides a details about places along a route (like gas stations and coffee on a road trip). I'm using the Google Maps API with the Places Library and RouteBoxer. I'm generating all the appropriate boxes with RouteBoxer, but when the boxes are passed to the Places Library I'm only getting back some of the places. Usually I'll get the first half of the route (on shorter routes) or a few random chunks (for longer routes). San Francisco to Seattle returns me gas stations around Seattle and around Medford, OR only.
Initially I thought maybe I was hitting the results cap of 200, but it's making a separate request for each box, and my total results often aren't hitting 200. Results returned are generally pretty consistent from what I can see. When looking at the details of my network requests and responses, it seems that the script is moving through the boxes making requests with the Places library, and suddenly it stops part way through.
The live app where you can see results and boxes is on Heroku.
My JavaScript isn't the strongest by any means. That's part of why I wanted to work with this API, so please pardon my ignorance if I'm making a trivial mistake. The full script is below. Any direction is tremendously appreciated!
var infowindow = new google.maps.InfoWindow();
var map;
var routeBoxer;
var service;
function initialize() {
directionsDisplay = new google.maps.DirectionsRenderer();
var mapOptions = {
zoom: 4,
center: new google.maps.LatLng(39, -98),
mapTypeId: google.maps.MapTypeId.ROADMAP,
};
map = new google.maps.Map(document.getElementById('map-canvas'), mapOptions);
service = new google.maps.places.PlacesService(map);
routeBoxer = new RouteBoxer();
directionService = new google.maps.DirectionsService();
directionsRenderer = new google.maps.DirectionsRenderer({ map: map })
directionsDisplay.setMap(map);
directionsDisplay.setPanel(document.getElementById('directions-panel'));
}
function calcRoute() {
var start = document.getElementById('start').value;
var end = document.getElementById('end').value;
var waypt1 = document.getElementById('waypoint1').value;
var waypt2 = document.getElementById('waypoint2').value;
var waypts = []
if (waypt1) {
waypts.push({
location:waypt1,
stopover:true});
}
if (waypt2) {
waypts.push({
location:waypt2,
stopover:true});
}
var request = {
origin: start,
destination: end,
waypoints: waypts,
optimizeWaypoints: true,
travelMode: google.maps.TravelMode.DRIVING
};
directionService.route(request, function(response, status) {
if (status == google.maps.DirectionsStatus.OK) {
directionsDisplay.setDirections(response);
// Build boxes around route
var path = response.routes[0].overview_path;
var boxes = routeBoxer.box(path, 2); // distance in km from route
drawBoxes(boxes);
for (var i=0; i < boxes.length; i++) {
var bounds = boxes[i];
findPlaces(bounds);
findPlacesByText(bounds);
}
} else {
alert("Directions query failed: " + status);
}
});
}
function findPlaces(bounds) {
var selectedTypes = [];
var inputElements = document.getElementsByClassName('placeOption');
for (var i=0; inputElements[i]; i++) {
if (inputElements[i].checked) {
selectedTypes.push(inputElements[i].value)
}
}
var request = {
bounds: bounds,
types: selectedTypes
};
if (selectedTypes.length > 0) {
service.radarSearch(request, callback);
}
}
function findPlacesByText(bounds) {
var selectedTypes = '';
var inputElements = document.getElementsByClassName('textOption');
for (var i=0; inputElements[i]; i++) {
if (inputElements[i].checked) {
selectedTypes += inputElements[i].value + ', '
}
}
var request = {
bounds: bounds,
query: selectedTypes
};
if (selectedTypes.length > 0) {
service.textSearch(request, callback);
}
}
function callback(results, status) {
if (status == google.maps.places.PlacesServiceStatus.OK) {
for (var i = 0; i < results.length; i++) {
createMarker(results[i]);
}
}
}
function createMarker(place) {
var marker = new google.maps.Marker({
map: map,
position: place.geometry.location
});
var request = {
reference: place.reference
};
google.maps.event.addListener(marker,'click',function(){
service.getDetails(request, function(place, status) {
if (status == google.maps.places.PlacesServiceStatus.OK) {
var contentStr = '<h5>' + place.name + '</h5><p>' + place.formatted_address;
if (!!place.formatted_phone_number) contentStr += '<br />' + place.formatted_phone_number;
if (!!place.website) contentStr += '<br /><a target="_blank" href="' + place.website + '">' + place.website + '</a>';
contentStr += '<br />' + place.types + '</p>';
infowindow.setContent(contentStr);
infowindow.open(map,marker);
} else {
var contentStr = "<h5>No Result, status=" + status + "</h5>";
infowindow.setContent(contentStr);
infowindow.open(map,marker);
}
});
});
}
google.maps.event.addDomListener(window, 'load', initialize);
After much experimentation and further research, I decided to try to slow my queries. The way I handled that was to write a new function that calls my query function, and then recursively calls itself with a delay for the next route box. If an OVER_QUERY_LIMIT status is returned, it recalls that box with an increased delay. So far it seems to be working great, but it quickly increases the delay to nearly a half second (or more) between calls, which can take a while if you have a long route with many boxes. My new function that seems to have solves the problem is below. It'll take some more fine-tuning to really get it right, but it's close!
var delay = 100;
...
function queryPlaces(boxes, searchIndex) {
// delay calls to Places API to prevent going over query limit (10/sec)
var bounds = boxes[searchIndex];
findPlaces(bounds);
findPlacesByText(bounds);
if (searchIndex > 0) {
searchIndex--;
setTimeout(queryPlaces, delay, boxes, searchIndex);
}
}