SQLite-backed implementation of the go-whosonfirst-spatial interfaces.
This is work in progress. It may change still. The goal is to have a package that conforms to the database.SpatialDatabase interface using mattn/go-sqlite3 and SQLite's RTree extension.
Documentation is incomplete.
This code depends on (4) tables as indexed by the go-whosonfirst-sqlite-features package:
- rtree - this table is used to perform point-in-polygon spatial queries.
- spr - this table is used to generate standard place response (SPR) results.
- properties - this table is used to append extra properties (to the SPR response) for
spatial.PropertiesResponseResultsresponses. - geojson - this table is used to satisfy the
whosonfirst/go-reader.Readerrequirements in thespatial.SpatialDatabaseinterface. It is meant to be a simple ID to bytes (or filehandle) lookup rather than a data structure that is parsed or queried.
Here's an example of the creating a compatible SQLite database for all the administative data in Canada using the wof-sqlite-index tool which is part of the go-whosonfirst-database-sqlite package:
$> ./bin/wof-sqlite-index \
-index-alt-files \
-spatial-tables \
-timings \
-dsn /usr/local/ca-alt.db \
-mode repo:// \
/usr/local/data/whosonfirst-data-admin-ca/
13:09:44.642004 [wof-sqlite-index-features] STATUS time to index rtree (11860) : 30.469010289s
13:09:44.642136 [wof-sqlite-index-features] STATUS time to index geometry (11860) : 5.155172377s
13:09:44.642141 [wof-sqlite-index-features] STATUS time to index properties (11860) : 4.631908497s
13:09:44.642143 [wof-sqlite-index-features] STATUS time to index spr (11860) : 19.160260741s
13:09:44.642146 [wof-sqlite-index-features] STATUS time to index all (11860) : 1m0.000182571s
13:10:44.642848 [wof-sqlite-index-features] STATUS time to index spr (32724) : 39.852608874s
13:10:44.642861 [wof-sqlite-index-features] STATUS time to index rtree (32724) : 57.361318918s
13:10:44.642864 [wof-sqlite-index-features] STATUS time to index geometry (32724) : 10.242155898s
13:10:44.642868 [wof-sqlite-index-features] STATUS time to index properties (32724) : 10.815961878s
13:10:44.642871 [wof-sqlite-index-features] STATUS time to index all (32724) : 2m0.000429956s
And then...
$> ./bin/pip \
-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/ca-alt.db' \
-latitude 45.572744 \
-longitude -73.586295
| jq \
| grep wof:id
2020/12/16 13:25:32 Time to point in polygon, 395.201983ms
"wof:id": "85633041",
"wof:id": "85874359",
"wof:id": "1108955735",
"wof:id": "85874359",
"wof:id": "85633041",
"wof:id": "890458661",
"wof:id": "136251273",
"wof:id": "136251273",
"wof:id": "85633041",
"wof:id": "136251273",
"wof:id": "85633041",
TBW: Indexing tables on start-up.
Database URIs for the go-whosonfirst-spatial-sqlite package take the form of:
"sqlite://" + {DATABASE_SQL_ENGINE} + "?dsn=" + {DATABASE_SQL_DSN}
Where DATABASE_SQL refers to the build-in database/sql package.
For example:
sqlite://sqlite3?dsn=test.db
By default this package bundles support for the mattn/go-sqlite3 driver but does NOT enable it by default. You will need to pass in the -tag mattn argument when building tools to enable it. This is the default behaviour in the cli Makefile target for building binary tools.
If you want or need to use the modernc.org/sqlite driver take a look at the database_mattn.go file for an example of how you might go about enabling it. As of this writing the modernc.org/sqlite package is not bundled with this package because it adds ~200MB of code to the vendor directory.
package main
import (
"context"
"encoding/json"
"fmt"
_ "github.com/mattn/go-sqlite3"
_ "github.com/whosonfirst/go-whosonfirst-spatial-sqlite"
"github.com/whosonfirst/go-whosonfirst-spatial/database"
"github.com/whosonfirst/go-whosonfirst-spatial/filter"
"github.com/whosonfirst/go-whosonfirst-spatial/geo"
"github.com/whosonfirst/go-whosonfirst-spatial/properties"
"github.com/whosonfirst/go-whosonfirst-spr"
)
func main() {
database_uri := "sqlite://sqlite3?dsn=whosonfirst.db"
properties_uri := "sqlite://sqlite3?dsn=whosonfirst.db"
latitude := 37.616951
longitude := -122.383747
props := []string{
"wof:concordances",
"wof:hierarchy",
"sfomuseum:*",
}
ctx := context.Background()
db, _ := database.NewSpatialDatabase(ctx, *database_uri)
pr, _ := properties.NewPropertiesReader(ctx, *properties_uri)
c, _ := geo.NewCoordinate(*longitude, *latitude)
f, _ := filter.NewSPRFilter()
r, _ := db.PointInPolygon(ctx, c, f)
r, _ = pr.PropertiesResponseResultsWithStandardPlacesResults(ctx, r, props)
enc, _ := json.Marshal(r)
fmt.Println(string(enc))
}
Error handling removed for the sake of brevity.
To be written
$> make cli go build -tags mattn -ldflags="-s -w" -mod vendor -o bin/http-server cmd/http-server/main.go go build -tags mattn -ldflags="-s -w" -mod vendor -o bin/grpc-server cmd/grpc-server/main.go go build -tags mattn -ldflags="-s -w" -mod vendor -o bin/grpc-client cmd/grpc-client/main.go go build -tags mattn -ldflags="-s -w" -mod vendor -o bin/update-hierarchies cmd/update-hierarchies/main.go go build -tags mattn -ldflags="-s -w" -mod vendor -o bin/pip cmd/pip/main.go
$> ./bin/pip -h
-alternate-geometry value
One or more alternate geometry labels (wof:alt_label) values to filter results by.
-cessation string
A valid EDTF date string.
-custom-placetypes string
A JSON-encoded string containing custom placetypes defined using the syntax described in the whosonfirst/go-whosonfirst-placetypes repository.
-enable-custom-placetypes
Enable wof:placetype values that are not explicitly defined in the whosonfirst/go-whosonfirst-placetypes repository.
-geometries string
Valid options are: all, alt, default. (default "all")
-inception string
A valid EDTF date string.
-is-ceased value
One or more existential flags (-1, 0, 1) to filter results by.
-is-current value
One or more existential flags (-1, 0, 1) to filter results by.
-is-deprecated value
One or more existential flags (-1, 0, 1) to filter results by.
-is-superseded value
One or more existential flags (-1, 0, 1) to filter results by.
-is-superseding value
One or more existential flags (-1, 0, 1) to filter results by.
-is-wof
Input data is WOF-flavoured GeoJSON. (Pass a value of '0' or 'false' if you need to index non-WOF documents. (default true)
-iterator-uri value
Zero or more URIs denoting data sources to use for indexing the spatial database at startup. URIs take the form of {ITERATOR_URI} + "#" + {PIPE-SEPARATED LIST OF ITERATOR SOURCES}. Where {ITERATOR_URI} is expected to be a registered whosonfirst/go-whosonfirst-iterate/v2 iterator (emitter) URI and {ITERATOR SOURCES} are valid input paths for that iterator. Supported whosonfirst/go-whosonfirst-iterate/v2 iterator schemes are: cwd://, directory://, featurecollection://, file://, filelist://, geojsonl://, null://, repo://.
-latitude float
A valid latitude.
-longitude float
A valid longitude.
-mode string
Valid options are: cli (default "cli")
-placetype value
One or more place types to filter results by.
-properties-reader-uri string
A valid whosonfirst/go-reader.Reader URI. Available options are: [fs:// null:// repo:// sqlite:// stdin://]. If the value is {spatial-database-uri} then the value of the '-spatial-database-uri' implements the reader.Reader interface and will be used.
-property value
One or more Who's On First properties to append to each result.
-server-uri string
A valid aaronland/go-http-server URI. (default "http://localhost:8080")
-sort-uri value
Zero or more whosonfirst/go-whosonfirst-spr/sort URIs.
-spatial-database-uri string
A valid whosonfirst/go-whosonfirst-spatial/data.SpatialDatabase URI. options are: [rtree:// sqlite://] (default "rtree://")
-verbose
Be chatty.
For example:
$> ./bin/pip \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/sfomuseum-data-architecture.db' \
-latitude 37.616951 \
-longitude -122.383747 \
-properties 'wof:hierarchy' \
-properties 'sfomuseum:*' \
| jq
{
"properties": [
{
"mz:is_ceased": 1,
"mz:is_current": 0,
"mz:is_deprecated": 0,
"mz:is_superseded": 1,
"mz:is_superseding": 1,
"mz:latitude": 37.617475,
"mz:longitude": -122.383371,
"mz:max_latitude": 37.61950174060331,
"mz:max_longitude": -122.38139655218178,
"mz:min_latitude": 37.61615511156664,
"mz:min_longitude": -122.3853565208227,
"mz:uri": "https://data.whosonfirst.org/115/939/616/5/1159396165.geojson",
"sfomuseum:is_sfo": 1,
"sfomuseum:placetype": "terminal",
"sfomuseum:terminal_id": "CENTRAL",
"wof:country": "US",
"wof:hierarchy": [
{
"building_id": 1159396339,
"campus_id": 102527513,
"continent_id": 102191575,
"country_id": 85633793,
"county_id": 102087579,
"locality_id": 85922583,
"neighbourhood_id": -1,
"region_id": 85688637,
"wing_id": 1159396165
}
],
"wof:id": 1159396165,
"wof:lastmodified": 1547232162,
"wof:name": "Central Terminal",
"wof:parent_id": 1159396339,
"wof:path": "115/939/616/5/1159396165.geojson",
"wof:placetype": "wing",
"wof:repo": "sfomuseum-data-architecture",
"wof:superseded_by": [
1159396149
],
"wof:supersedes": [
1159396171
]
},
... and so on
}
]
It is possible to filter results by one or more existential flags (-is-current, -is-ceased, -is-deprecated, -is-superseded, -is-superseding). For example, this query for a point at SFO airport returns 24 possible candidates:
$> ./bin/pip \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/sfom-arch.db' \
-latitude 37.616951 \
-longitude -122.383747
| jq | grep wof:id | wc -l
2020/12/17 17:01:16 Time to point in polygon, 38.131108ms
24
But when filtered using the -is-current 1 flag there is only a single result:
$> ./bin/pip \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/sfom-arch.db' \
-latitude 37.616951 \
-longitude -122.383747 \
-is-current 1
| jq
2020/12/17 17:00:11 Time to point in polygon, 46.401411ms
{
"places": [
{
"wof:id": "1477855655",
"wof:parent_id": "1477855607",
"wof:name": "Terminal 2 Main Hall",
"wof:country": "US",
"wof:placetype": "concourse",
"mz:latitude": 37.617044,
"mz:longitude": -122.383533,
"mz:min_latitude": 37.61569458544746,
"mz:min_longitude": 37.617044,
"mz:max_latitude": -122.3849257355292,
"mz:max_longitude": -122.38294919235318,
"mz:is_current": 1,
"mz:is_deprecated": 0,
"mz:is_ceased": 1,
"mz:is_superseded": 0,
"mz:is_superseding": 1,
"wof:path": "147/785/565/5/1477855655.geojson",
"wof:repo": "sfomuseum-data-architecture",
"wof:lastmodified": 1569430965
}
]
}
You can also filter results to one or more specific alternate geometry labels. For example here are the quattroshapes and whosonfirst-reversegeo geometries for a point in the city of Montreal, using a SQLite database created from the whosonfirst-data-admin-ca database:
$> ./bin/pip \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/ca-alt.db' \
-latitude 45.572744 \
-longitude -73.586295 \
-alternate-geometry quattroshapes \
-alternate-geometry whosonfirst-reversegeo
| jq | grep wof:name
2020/12/17 16:52:08 Time to point in polygon, 419.727612ms
"wof:name": "136251273 alt geometry (quattroshapes)",
"wof:name": "85633041 alt geometry (whosonfirst-reversegeo)",
"wof:name": "85874359 alt geometry (quattroshapes)",
Note: These examples assumes a database that was previously indexed using the whosonfirst/go-whosonfirst-database-sqlite wof-sqlite-index tool. For example:
$> ./bin/wof-sqlite-index \
-rtree \
-spr \
-properties \
-dsn /tmp/test.db
-mode repo:// \
/usr/local/data/sfomuseum-data-architecture/
The exclude alternate geometries from query results pass the -geometries default flag:
$> ./bin/pip \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/ca-alt.db' \
-latitude 45.572744 \
-longitude -73.586295 \
-geometries default
| jq | grep wof:name
2020/12/17 17:07:31 Time to point in polygon, 405.430776ms
"wof:name": "Canada",
"wof:name": "Saint-Leonard",
"wof:name": "Quartier Port-Maurice",
"wof:name": "Montreal",
"wof:name": "Quebec",
To limit query results to only alternate geometries pass the -geometries alternate flag:
$> ./bin/pip \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/ca-alt.db' \
-latitude 45.572744 \
-longitude -73.586295 \
-geometries alternate
2020/12/17 17:07:39 Time to point in polygon, 366.347365ms
"wof:name": "85874359 alt geometry (quattroshapes)",
"wof:name": "85633041 alt geometry (naturalearth)",
"wof:name": "85633041 alt geometry (naturalearth-display-terrestrial-zoom6)",
"wof:name": "136251273 alt geometry (whosonfirst)",
"wof:name": "136251273 alt geometry (quattroshapes)",
"wof:name": "85633041 alt geometry (whosonfirst-reversegeo)",
Support for remotely-hosted SQLite databases is available. For example:
$> go run -mod vendor cmd/pip/main.go \
-spatial-database-uri 'sqlite://sqlite3?dsn=http://localhost:8080/sfomuseum-architecture.db' \
-latitude 37.616951 \
-longitude -122.383747 \
-is-current 1 \
| json_pp | grep "wof:name"
"wof:name" : "Terminal Two Arrivals",
"wof:name" : "Terminal 2",
"wof:name" : "SFO Terminal Complex",
"wof:name" : "Terminal 2 Main Hall",
"wof:name" : "SFO Terminal Complex",
Big thanks to @psanford 's sqlitevfshttp package for making this possible.
$> ./bin/http-server -h
-authenticator-uri string
A valid sfomuseum/go-http-auth URI. (default "null://")
-cors-allow-credentials
Allow HTTP credentials to be included in CORS requests.
-cors-origin value
One or more hosts to allow CORS requests from; may be a comma-separated list.
-custom-placetypes string
A JSON-encoded string containing custom placetypes defined using the syntax described in the whosonfirst/go-whosonfirst-placetypes repository.
-enable-cors
Enable CORS headers for data-related and API handlers.
-enable-custom-placetypes
Enable wof:placetype values that are not explicitly defined in the whosonfirst/go-whosonfirst-placetypes repository.
-enable-geojson
Enable GeoJSON output for point-in-polygon API calls.
-enable-gzip
Enable gzip-encoding for data-related and API handlers.
-enable-www
Enable the interactive /debug endpoint to query points and display results.
-iterator-uri value
Zero or more URIs denoting data sources to use for indexing the spatial database at startup. URIs take the form of {ITERATOR_URI} + "#" + {PIPE-SEPARATED LIST OF ITERATOR SOURCES}. Where {ITERATOR_URI} is expected to be a registered whosonfirst/go-whosonfirst-iterate/v2 iterator (emitter) URI and {ITERATOR SOURCES} are valid input paths for that iterator. Supported whosonfirst/go-whosonfirst-iterate/v2 iterator schemes are: cwd://, directory://, featurecollection://, file://, filelist://, geojsonl://, null://, repo://.
-leaflet-initial-latitude float
The initial latitude for map views to use. (default 37.616906)
-leaflet-initial-longitude float
The initial longitude for map views to use. (default -122.386665)
-leaflet-initial-zoom int
The initial zoom level for map views to use. (default 14)
-leaflet-max-bounds string
An optional comma-separated bounding box ({MINX},{MINY},{MAXX},{MAXY}) to set the boundary for map views.
-log-timings
Emit timing metrics to the application's logger
-map-provider-uri string
A valid aaronland/go-http-maps/provider URI. (default "leaflet://?leaflet-tile-url=https://tile.openstreetmap.org/{z}/{x}/{y}.png")
-path-api string
The root URL for all API handlers (default "/api")
-path-data string
The URL for data (GeoJSON) handler (default "/data")
-path-ping string
The URL for the ping (health check) handler (default "/health/ping")
-path-pip string
The URL for the point in polygon web handler (default "/point-in-polygon")
-path-prefix string
Prepend this prefix to all assets (but not HTTP handlers). This is mostly for API Gateway integrations.
-properties-reader-uri string
A valid whosonfirst/go-reader.Reader URI. Available options are: [fs:// null:// repo:// sqlite:// stdin://]. If the value is {spatial-database-uri} then the value of the '-spatial-database-uri' implements the reader.Reader interface and will be used.
-server-uri string
A valid aaronland/go-http-server URI. (default "http://localhost:8080")
-spatial-database-uri string
A valid whosonfirst/go-whosonfirst-spatial/data.SpatialDatabase URI. options are: [rtree:// sqlite://] (default "rtree://")
For example:
$> bin/http-server \
-enable-www \
-spatial-database-uri 'sqlite://sqlite3?dsn=modernc:///usr/local/data/sfomuseum-data-architecture.db'
A couple things to note:
- The SQLite databases specified in the
sqlite:///?dsnstring are expected to minimally contain thertreeandsprandpropertiestables confirming to the schemas defined in the go-whosonfirst-sqlite-features. They are typically produced by the go-whosonfirst-sqlite-features-index package. See the documentation in the go-whosonfirst-spatial-sqlite package for details.
When you visit http://localhost:8080 in your web browser you should see something like this:
If you don't need, or want, to expose a user-facing interface simply remove the -enable-www and -nextzen-apikey flags. For example:
$> bin/http-server \
-spatial-database-uri 'sqlite://sqlite3?dsn/usr/local/data/sfomuseum-data-architecture.db'
And then to query the point-in-polygon API you would do something like this:
$> curl -X POST -s 'http://localhost:8080/api/point-in-polygon' -d '{"latitude":37.61701894316063, "longitude":-122.3866653442383}'
{
"places": [
{
"wof:id": 1360665043,
"wof:parent_id": -1,
"wof:name": "Central Parking Garage",
"wof:placetype": "wing",
"wof:country": "US",
"wof:repo": "sfomuseum-data-architecture",
"wof:path": "136/066/504/3/1360665043.geojson",
"wof:superseded_by": [],
"wof:supersedes": [
1360665035
],
"mz:uri": "https://data.whosonfirst.org/136/066/504/3/1360665043.geojson",
"mz:latitude": 37.616332,
"mz:longitude": -122.386047,
"mz:min_latitude": 37.61498599208708,
"mz:min_longitude": -122.38779093748578,
"mz:max_latitude": 37.61767331604971,
"mz:max_longitude": -122.38429192207244,
"mz:is_current": 0,
"mz:is_ceased": 1,
"mz:is_deprecated": 0,
"mz:is_superseded": 0,
"mz:is_superseding": 1,
"wof:lastmodified": 1547232156
}
... and so on
}
By default, results are returned as a list of "standard places response" (SPR) elements. You can also return results as a GeoJSON FeatureCollection by passing the -enable-geojson flag to the server and including a format=geojson query parameter with requests. For example:
$> bin/http-server \
-enable-geojson \
-spatial-database-uri 'sqlite://sqlite3?dsn=/usr/local/data/sfomuseum-data-architecture.db'
And then:
$> curl -s -XPOST -H 'Accept: application/geo+json' 'http://localhost:8080/api/point-in-polygon' -d '{"latitude":37.61701894316063,"longitude":-122.3866653442383 }'
{
"type": "FeatureCollection",
"features": [
{
"type": "Feature",
"geometry": {
"type": "MultiPolygon",
"coordinates": [ ...omitted for the sake of brevity ]
},
"properties": {
"mz:is_ceased": 1,
"mz:is_current": 0,
"mz:is_deprecated": 0,
"mz:is_superseded": 0,
"mz:is_superseding": 1,
"mz:latitude": 37.616332,
"mz:longitude": -122.386047,
"mz:max_latitude": 37.61767331604971,
"mz:max_longitude": -122.38429192207244,
"mz:min_latitude": 37.61498599208708,
"mz:min_longitude": -122.38779093748578,
"mz:uri": "https://data.whosonfirst.org/136/066/504/3/1360665043.geojson",
"wof:country": "US",
"wof:id": 1360665043,
"wof:lastmodified": 1547232156,
"wof:name": "Central Parking Garage",
"wof:parent_id": -1,
"wof:path": "136/066/504/3/1360665043.geojson",
"wof:placetype": "wing",
"wof:repo": "sfomuseum-data-architecture",
"wof:superseded_by": [],
"wof:supersedes": [
1360665035
]
}
}
... and so on
]
}
$> ./bin/grpc-server -h
-custom-placetypes string
A JSON-encoded string containing custom placetypes defined using the syntax described in the whosonfirst/go-whosonfirst-placetypes repository.
-enable-custom-placetypes
Enable wof:placetype values that are not explicitly defined in the whosonfirst/go-whosonfirst-placetypes repository.
-host string
The host to listen for requests on (default "localhost")
-is-wof
Input data is WOF-flavoured GeoJSON. (Pass a value of '0' or 'false' if you need to index non-WOF documents. (default true)
-iterator-uri value
Zero or more URIs denoting data sources to use for indexing the spatial database at startup. URIs take the form of {ITERATOR_URI} + "#" + {PIPE-SEPARATED LIST OF ITERATOR SOURCES}. Where {ITERATOR_URI} is expected to be a registered whosonfirst/go-whosonfirst-iterate/v2 iterator (emitter) URI and {ITERATOR SOURCES} are valid input paths for that iterator. Supported whosonfirst/go-whosonfirst-iterate/v2 iterator schemes are: cwd://, directory://, featurecollection://, file://, filelist://, geojsonl://, null://, repo://.
-port int
The port to listen for requests on (default 8082)
-properties-reader-uri string
A valid whosonfirst/go-reader.Reader URI. Available options are: [fs:// null:// repo:// sqlite:// stdin://]. If the value is {spatial-database-uri} then the value of the '-spatial-database-uri' implements the reader.Reader interface and will be used.
-spatial-database-uri string
A valid whosonfirst/go-whosonfirst-spatial/data.SpatialDatabase URI. options are: [rtree:// sqlite://] (default "rtree://")
For example:
$> ./bin/grpc-server -spatial-database-uri 'sqlite://sqlite3?dsn=modernc:///usr/local/data/arch.db'
2024/07/19 10:52:47 Listening on localhost:8082
And then in another terminal:
$> ./bin/grpc-client -latitude 37.621131 -longitude -122.384292 | jq '.places[]["name"]'
"San Francisco International Airport"
$> ./bin/grpc-client -h
-alternate-geometry value
One or more alternate geometry labels (wof:alt_label) values to filter results by.
-cessation string
A valid EDTF date string.
-geometries string
Valid options are: all, alt, default. (default "all")
-host string
The host of the gRPC server to connect to. (default "localhost")
-inception string
A valid EDTF date string.
-is-ceased value
One or more existential flags (-1, 0, 1) to filter results by.
-is-current value
One or more existential flags (-1, 0, 1) to filter results by.
-is-deprecated value
One or more existential flags (-1, 0, 1) to filter results by.
-is-superseded value
One or more existential flags (-1, 0, 1) to filter results by.
-is-superseding value
One or more existential flags (-1, 0, 1) to filter results by.
-latitude float
A valid latitude.
-longitude float
A valid longitude.
-null
Emit results to /dev/null
-placetype value
One or more place types to filter results by.
-port int
The port of the gRPC server to connect to. (default 8082)
-property value
One or more Who's On First properties to append to each result.
-sort-uri value
Zero or more whosonfirst/go-whosonfirst-spr/sort URIs.
-stdout
Emit results to STDOUT (default true)
For example:
$> ./bin/grpc-client -latitude 37.621131 -longitude -122.384292 | jq '.places[]["name"]'
"San Francisco International Airport"
- https://github.com/whosonfirst/go-whosonfirst-spatial
- https://github.com/whosonfirst/go-whosonfirst-spatial-www
- https://github.com/whosonfirst/go-whosonfirst-spatial-grpc
- https://github.com/whosonfirst/go-whosonfirst-database
- https://github.com/whosonfirst/go-whosonfirst-database-sqlite
- https://github.com/whosonfirst/go-reader