documentation/getting-started/002-search.md

Mapzen Search: Finding places

Geospatial search, frequently referred to as geocoding, is the process of matching an address to its corresponding geographic coordinates. There's nothing inherent in the words we use to describe an address that conveys its location at some coordinates on earth, i.e. [lat,lon]. Making the leap from text to coordinates is an intricate and challenging process. Lucky for you, we've done all the hard work and made it accessible though a free web service.

Build a query

The Mapzen Search request takes the form of https://search.mapzen.com/v1/search?api_key={your-api-key}, where the JSON inputs inside the {} include search parameters such as the text to find and filtering options. Note that you must append your own Mapzen Search API key to the URL, following &api_key= at the end.

Search the world

In the simplest search, you can provide only one parameter, the text you want to match in any part of the location details. To accomplish this, build a query where the text is set to the item you want to find.

For example, if you want to find a YMCA facility, here's what you'd need to append to the base URL of the service, search.mapzen.com.

/v1/search?api_key={YOUR-KEY}&text=YMCA

Note the parameter values are set as follows:

parameter	value
api_key	get yours here
text	YMCA

If you clicked on the query link above, you probably saw some cool GeoJSON, more on that later, with the following set of places in the results:

• YMCA, Bargoed Community, United Kingdom

• YMCA, Nunspeet, Gelderland
• YMCA, Belleville, IL
• YMCA, Forest City, IA
• YMCA, Fargo, ND
• YMCA, Taipei, Taipei City
• YMCA, Orpington, Greater London
• YMCA, Frisco, TX
• YMCA, Jefferson, OH
• YMCA, Belleville, IL

Note that the results are spread out throughout the world because you have not given your current location or provided any other geographic context in which to search.

Narrow your search

If you are looking for places in a particular region, or country, or only want to look in the immediate vicinity of a user with a known location, you can narrow your search to an area. There are different ways of including a region in your query. Mapzen Search currently supports three types: country, rectangle, and country.

Search within a particular country

Sometimes your work might require that all the search results be from a particular country. To do this, you can set the boundary.country parameter value to the alpha-2 or alpha-3 ISO-3166 country code.

Now, you want to search for YMCA again, but this time only in Great Britain. To do this, you will need to know that the alpha-3 code for Great Britain is GBR and set the parameters like this:

/v1/search?api_key={YOUR-KEY}&text=YMCA&boundary.country=GBR

parameter	value
api_key	get yours here
text	YMCA
boundary.country	GBR

Note that all the results reside within Great Britain:

• YMCA, Bargoed Community, United Kingdom

• YMCA, Orpington, Greater London
• YMCA, Erdington, West Midlands
• YMCA, Malvern CP, United Kingdom
• YMCA, Ancoats, Greater Manchester
• YMCA, Carmarthen Community, United Kingdom
• YMCA, Halebank, Cheshire
• YMCA, Brightlingsea CP, United Kingdom
• YMCA, Lenton Abbey, Nottinghamshire
• YMCA, Old Clee, Lincolnshire

If you attempt the same search request with different country codes, you can see how the results change.

/v1/search?api_key={YOUR-KEY}&text=YMCA&boundary.country=USA

Results in the United States:

• YMCA, Belleville, IL

• YMCA, Forest City, IA
• YMCA, Fargo, ND
• YMCA, Frisco, TX
• YMCA, Jefferson, OH
• YMCA, Belleville, IL
• YMCA, Chapel Hill, NC
• YMCA, West Lampeter, PA
• YMCA, Bremerton, WA
• YMCA, Westerly, RI

Search within a rectangular region

In the case where you need to specify the boundary using a rectangle, all we need is a pair of coordinates on earth. Here are a few examples:

Let's say you wanted to find museums in the state of Texas. You'd need to set the boundary.rect.* parameter grouping to values representing the bounding box around Texas: min_lon=-106.65 min_lat=25.84 max_lon=-93.51 max_lat=36.5

PRO TIP: You can lookup a bounding box for a known region here

/v1/search?api_key={YOUR-KEY}&text=YMCA&boundary.rect.min_lat=25.84&boundary.rect.min_lon=-106.65&boundary.rect.max_lat=36.5&boundary.rect.max_lon=-93.51

parameter	value
api_key	get yours here
text	YMCA
boundary.rect.min_lat	25.84
boundary.rect.min_lon	-106.65
boundary.rect.max_lat	36.5
boundary.rect.max_lon	-93.51

• YMCA, Austin, TX

• YMCA, Frisco, TX
• Y.M.C.A, Fort Worth, TX
• YMCA, Rockwall, TX
• YMCA, Missouri City, TX
• YMCA, Northshore, TX
• YMCA, Austin, TX
• YMCA, Tulsa, OK
• YMCA, Los Alamos, NM
• YMCA, Tulsa, OK

Search within a circular region

Sometimes you don't have a rectangle to work with, but rather you've got a point on earth, for example your location coordinates, and a maximum distance within which acceptable results can be located.

Example time

Find all YMCA locations within a 35km radius of a spot in Ontario, Canada, This time, we'll use the boundary.circle.* parameter grouping to get the job done. boundary.circle.lat and boundary.circle.lon should be set to your location in Madrid, while boundary.circle.radius should be set to the acceptable distance from that location. Note that the boundary.circle.radius parameter is always specified in kilometers.

/v1/search?api_key={YOUR_API_KEY}&text=YMCA&boundary.circle.lon=-79.186484&boundary.circle.lat=43.818156&boundary.circle.radius=35

parameter	value
api_key	get yours here
text	YMCA
boundary.circle.lat	43.818156
boundary.circle.lon	-79.186484
boundary.circle.radius	35

You can see the results have fewer than the standard 10 items, because there aren't that many YMCA locations in the specified radius:

• YMCA, Toronto, Ontario

• YMCA, Markham, Ontario
• YMCA, Toronto, Ontario
• Metro Central YMCA, Toronto, Ontario
• Pinnacle Jr YMCA, Toronto, Ontario
• Cooper Koo Family Cherry Street YMCA Centre, Toronto, Ontario

We respect your boundaries

If you're going to attempt using multiple boundary types in a single search request, be aware that the results will come from the intersection of all the boundaries! So if you provide regions that don't overlap, you'll be looking at an empty set of results. You've been warned. Here's a visual of how it works:

Prioritizing Nearby Places

Many usecases call for the ability to surface nearby results to the front of the list, while still allow important matches from further away to be visible. If that's your conundrum, here's what you've got to do.

...around a point of focus

Search will focus on a given point anywhere on earth, and results within ~100km will be prioritized higher, thereby surfacing highest in the list. Once all the nearby results have been found, additional results will come from the rest of the world, without any further location-based prioritization.

Example time

Let's find YMCA again, but this time near Sydney Opera House, Australia

/v1/search?api_key={YOUR-KEY}&text=YMCA&focus.point.lat=-33.856680&focus.point.lon=151.215281

parameter	value
api_key	get yours here
text	YMCA
focus.point.lat	-33.856680
focus.point.lon	151.215281

Looking at the results, you can see that the few locations closer to Sydney show up at the top of the list, sorted by distance. You also still get back a significant amount of remote locations, for a well balanced mix. Oh, and since you provided a focus point, we can now compute distance from that point for each result, so check that out in each feature.

• YMCA, Redfern, New South Wales [distance: 3.836]

• YMCA, St Ives (NSW), New South Wales [distance: 14.844]
• YMCA, Epping (NSW), New South Wales [distance: 16.583]
• YMCA, Revesby, New South Wales [distance: 21.335]
• YMCA, Kochâang, South Gyeongsang [distance: 8071.436]
• YMCA, Center, IN [distance: 14882.675]
• YMCA, Lake Villa, IL [distance: 14847.667]
• YMCA, Onondaga, NY [distance: 15818.08]
• YMCA, 's-Gravenhage, Zuid-Holland [distance: 16688.292]
• YMCA, Loughborough, United Kingdom [distance: 16978.367]

Prioritizing within Boundaries

Now that we've seen how to use boundary and focus to narrow down and sort your results, let's examine a few scenarios where they work well together.

Prioritize within a country

TBD: insert image here

Example time

Let's revisit the YMCA search we conducted with a focus around the Sydney Opera House. When providing only focus.point, we saw results come back from distant parts of the world, as expected. But say you wanted to only see results from the country in which your focus point lies. Let's combine that same focus point, Sydney Opera House, with the country boundary of Australia. Check this out.

/v1/search?api_key={YOUR-KEY}&text=YMCA&focus.point.lat=-33.856680&focus.point.lon=151.215281

parameter	value
api_key	get yours here
text	YMCA
focus.point.lat	-33.856680
focus.point.lon	151.215281
boundary.country	AUS

The results below look very different from the ones we saw previously with only a focus point specified. These results are all from within Australia. You'll note the closest results show up at the beginning of the list, which is facilitated by the focus parameter. Pretty spectacular, right!?

• YMCA, Redfern, New South Wales [distance: 3.836]

• YMCA, St Ives (NSW), New South Wales [distance: 14.844]
• YMCA, Epping (NSW), New South Wales [distance: 16.583]
• YMCA, Revesby, New South Wales [distance: 21.335]
• YMCA, Larrakeyah, Northern Territory [distance: 3144.296]
• YMCA, Kepnock, Queensland [distance: 1001.657]
• YMCA, Kings Meadows, Tasmania [distance: 917.144]
• YMCA, Katherine East, Northern Territory [distance: 2873.376]
• YMCA, Sadadeen, Northern Territory [distance: 2026.731]
• YMCA, Ararat, Victoria [distance: 841.022]

Prioritize within a circular boundary

TBD: insert image here

Let's say you're looking for the nearest YMCA locations, and are willing to travel no further than 50km from your current location. You'd like the results to be sorted by distance from current location, in order to make your selection process easier. We can get this behavior by using focus.point in combination with boundary.circle.*. We can reuse the focus.point.* values as the boundary.circle.lat and boundary.circle.lon, and simply specify the required boundary.circle.radius value in kilometers.

/v1/search?api_key={YOUR-KEY}&text=YMCA&focus.point.lat=-33.856680&focus.point.lon=151.215281&boundary.circle.lat=-33.856680&boundary.circle.lon=151.215281&boundary.circle.radius=50

parameter	value
api_key	get yours here
text	YMCA
focus.point.lat	-33.856680
focus.point.lon	151.215281
boundary.circle.lat	-33.856680
boundary.circle.lon	151.215281
boundary.circle.radius	50

Check out the results. They are all less than 50km away from the focus point:

• YMCA, Redfern, New South Wales [distance: 3.836]

• YMCA, St Ives (NSW), New South Wales [distance: 14.844]
• YMCA, Epping (NSW), New South Wales [distance: 16.583]
• YMCA, Revesby, New South Wales [distance: 21.335]
• Caringbah YMCA, Caringbah, New South Wales [distance: 22.543]
• YMCA building, Loftus, New South Wales [distance: 25.756]

Filtering your Search...

Mapzen search offers two types of options for selecting the dataset you want to search:

• sources : the originating source of the data
• layers : the kind of place you're looking to find

...by Data Source

Mapzen Search brings together data from various open sources. All the search examples we've seen so far, return a mix of results from all the different sources. Here's a list of what we import at this time:

source	name	short name
OpenStreetMap	openstreetmap	osm
OpenAddresses	openaddresses	oa
Quattroshapes	quattroshapes	qs
GeoNames	geonames	ga

We've added a helpful sources parameter to the Search API, to allow users to select which of these data sources they want to include in their search. So if you're only intersted in searching OpenAddressses, for example, your query would look as follows.

Example time

Let's search for YMCA again but only within the OpenAddresses data source.

/v1/search?api_key={YOUR-KEY}&text=YMCA&sources=oa

parameter	value
api_key	get yours here
text	YMCA
sources	oa

Since OpenAddresses is, as the name suggests, only address data, here's what you can expect to find:

• 0 Ymca, New Brunswick

• 0 Ymca Drive, Cary, NC
• 14843 Ymca Lane, Cormorant, MN
• 14660 Ymca Lane, Cormorant, MN
• 6221 Ymca Lane, Northampton County, VA
• 6223 Ymca Lane, Northampton County, VA
• 74 Ymca Road, Wairoa District, Hawke's Bay Region
• 108 Ymca Drive, Clinton, SC
• 101 Ymca Drive, Kannapolis, NC
• 31440 Ymca Road, Washington, OH

If you wanted to combine several data sources together, you would simply set sources to a comma separated list of desired source names. Note that the order of the comma separated values does not impact sorting order of the results. They are still sorted based on the linguistic match quality to text and distance from focus, if one was specified.

/v1/search?api_key={YOUR-KEY}&text=YMCA&sources=osm,gn

parameter	value
api_key	get yours here
text	YMCA
sources	osm,gn

...by Data Type

Mapzen Search brings together a variety of place types into a single database. We refer to these place types as layers, and think of them as ranging from fine to coarse. Our layers are derived from the hierarchy created by the gazetteer Who's on First and can be used to facilitate coarse geocoding. Here's a list of the types of places you could find in our results, sorted by granularity:

layer	description
venue	points of interest, businesses, things with walls
address	places with a street address
country	places that issue passports, nations, nation-states
region	states and provinces
county	official governmental area; usually bigger than a locality, almost always smaller than a region
locality	towns, hamlets, cities, etc.
localadmin	TBD
neighbourhood	...ehm, neighbourhoods
coarse	alias for simultaneously using country, region, county, locality, localadmin, and neighbourhood

Example time

*** COMING SOON***

Using Autocomplete & Search Together

For end-user applications, /autocomplete is intended to be used alongside /search to facilitate real-time feedback for user s

Results

Now that you've seen some examples of search, let's examine the results closer. When requesting search results you will always get back GeoJSON results, unless something goes terribly wrong, in which case you'll get a really helpful error.

You can go here to learn more about the GeoJSON data format specification. We'll assume you're familiar with the general layout and only point out some important details here.

You will find the following top-level structure to every response:

{
  "geocoding":{...},
  "type":"FeatureCollection",
  "features":[...],
  "bbox":[...]
}

For the purposes of getting started quickly, let's keep our focus on the features property of the result. This is where you will find the list of results that best matched your input parameters.

Each item in this list will contain all the information needed to identify it in human-readable format in the properties block, as well as computer friendly coordinates in the geometry property. Note the label property, which is a human-friendly representation of the place, ready to be displayed to an end-user.

{  
  "type":"Feature",
  "properties":{  
    "gid":"...",
    "layer":"address",
    "source":"osm",
    "name":"30 West 26th Street",
    "housenumber":"30",
    "street":"West 26th Street",
    "postalcode":"10010",
    "country_a":"USA",
    "country":"United States",
    "region":"New York",
    "region_a":"NY",
    "county":"New York County",
    "localadmin":"Manhattan",
    "locality":"New York",
    "neighbourhood":"Flatiron District",
    "confidence":0.9624939994613662,
    "label":"30 West 26th Street, Manhattan, NY"
  },
  "geometry":{  
    "type":"Point",
    "coordinates":[  
      -73.990342,
      40.744243
    ]
  }
}

There is so much more to tell you about the plethora of data being returned for each search, we had to split it out into its own section. Read more about the response format.

Result count

You may have noticed that there were 10 places in the results for all the previous search examples. That's the default number of results the API will return, unless otherwise specified.

Example time

Want a single result? Just set the size parameter to the desired number:

parameter	value
api_key	get yours here
text	YMCA
size	1

/v1/search?api_key={YOUR-KEY}&text=stinky beach&size=1

How about 25 results?

/v1/search?api_key={YOUR-KEY}&text=YMCA&size=25

parameter	value
api_key	get yours here
text	YMCA
size	25

cApiTaliZAtioN

You may have noticed already that cApiTaliZAtioN isn't a big deal for search. You can type ymca or YMCA or even yMcA. See for yourself by comparing the results of the previous search to the following:

/v1/search?api_key={YOUR-KEY}&text=yMcA