Repository files navigation

FastVector is aPostGISvector tiles built for serving large geometric tables. FastVector is written inPython using theFastAPI web framework.

FastVector is built with inspriration fromTiMVT.

It defers from TiMVT in the fact that it has multi server/database support, cql_filtering, and a fields parameter.

Source Code:https://github.com/mkeller3/FastVector

FastVector requires PostGIS >= 2.4.0.

In order for the api to work you will need to edit theconfig.py file with your database connections.

Example

DATABASES= {"data": {"host":"localhost",# Hostname of the server"database":"data",# Name of the database"username":"postgres",# Name of the user, ideally only SELECT rights"password":"postgres",# Password of the user"port":5432,# Port number for PostgreSQL"cache_age_in_seconds":6000,# Number of seconds for tile to be cache in clients browser. You can set to zero if you do not want any caching."max_features_per_tile":100000# Maximum features per tile. This helps with performance for tables with a large number of rows.    }}

To run the app locallyuvicorn main:app --reload

Build Dockerfile into a docker image to deploy to the cloud.

Mapbox GL JS is a JavaScript library for interactive, customizable vector maps on the web. It takes map styles that conform to theMapbox Style Specification, applies them to vector tiles thatconform to theMapbox Vector Tile Specification, and renders them usingWebGL.

You can add a layer to the map and specify TileJSON endpoint as a vector source URL. You should also specify asource-layer property. ForTable JSON it is{schema_name}.{table_name} by default.

map.addSource('points',{type:'vector',url:`http://localhost:8000/api/v1/tiles/data/public/state_centroids/{z}/{x}/{y}.pbf`});map.addLayer({'id':'state_centroids','type':'circle','source':'state_centroids','source-layer':'public.state_centroids','paint':{'circle-color':'red'}});

MapLibre is an Open-source JavaScript library for publishing maps on your websites.

map.addSource('state_centroids',{type:'vector',url:`http://localhost:8000/api/v1/tiles/data/public/state_centroids/{z}/{x}/{y}.pbf`});map.addLayer({'id':'points','type':'circle','source':'state_centroids','source-layer':'public.state_centroids','paint':{'circle-color':'red'}});

Leaflet is the leading open-source JavaScript library for mobile-friendly interactive maps.

You can add vector tiles usingLeaflet.VectorGrid plugin. You must initialize aVectorGrid.Protobuf with a URL template, just like in L.TileLayers. The difference is that you should define the styling for all the features.

L.vectorGrid.protobuf('http://localhost:8000/api/v1/tiles/data/public/state_centroids/{z}/{x}/{y}.pbf',{vectorTileLayerStyles:{'public.state_centroids':{color:'red',fill:true}}}).addTo(map);

Tables endpoint provides a listing of all the tables available to query as vector tiles.

Tables endpoint is available at/api/v1/table/tables.json

curl http://localhost:8000/api/v1/table/tables.json

Example Response

[  {"name":"states","schema":"public","type":"table","id":"public.states","database":"data","detailurl":"http://127.0.0.1:8000/api/v1/table/data/public/states.json","viewerurl":"http://127.0.0.1:8000/viewer/data/public/states"  },  {},...

Table endpoint is available at/api/v1/table/{database}/{scheme}/{table}.json

For example,states table inpublic schema indata database will be available at/api/v1/table/data/public/states.json

curl http://localhost:8000/api/v1/table/data/public/states.json

Example Response

{"id":"public.states","schema":"public","tileurl":"http://127.0.0.1:8000/api/v1/tiles/data/public/states/{z}/{x}/{y}.pbf","viewerurl":"http://127.0.0.1:8000/viewer/data/public/states","properties": [    {"name":"gid","type":"integer","description":null    },    {"name":"geom","type":"geometry","description":null    },    {"name":"state_name","type":"character varying","description":null    },    {"name":"state_fips","type":"character varying","description":null    },    {"name":"state_abbr","type":"character varying","description":null    },    {"name":"population","type":"integer","description":null    }  ],"geometrytype":"ST_MultiPolygon","type":"table","minzoom":0,"maxzoom":22,"bounds": [-178.2175984,18.9217863,-66.9692709999999,71.406235408712  ],"center": [-112.96125695842262,45.69082939790446  ]}

Tiles endpoint is available at/api/v1/tiles/{database}/{scheme}/{table}/{z}/{x}/{y}.pbf

For example,states table inpublic schema indata database will be available at/api/v1/table/data/public/states/{z}/{x}/{y}.pbf

If you have a table with a large amount of fields you can limit the amount of fields returned using the fields parameter.

If you use the fields parameter the tile will not be cached on the server.

For example, if we only want thestate_fips field.

/api/v1/table/data/public/states/{z}/{x}/{y}.pbf?fields=state_fips

CQL filtering is enabled viapygeofilter. This allows you to dynamically filter your tiles database size for larger tiles.

For example, filter the states layer to only show states with a population greater than 1,000,000.

/api/v1/table/data/public/states/{z}/{x}/{y}.pbf?cql_filter=population>1000000

Geoserver has examples of using cql filters.

If you use the cql_filter parameter the tile will not be cached on the server.

TableTileJSON endpoint is available at/api/v1/tiles/{database}/{scheme}/{table}.json

For example,states table inpublic schema indata database will be available at/api/v1/tiles/data/public/states.json

curl http://localhost:8000/api/v1/tiles/data/public/states.json

Example Response

{"tilejson":"2.2.0","name":"public.states","version":"1.0.0","scheme":"xyz","tiles": ["http://127.0.0.1:8000/api/v1/tiles/data/public/states/{z}/{x}/{y}.pbf"  ],"viewerurl":"http://127.0.0.1:8000/viewer/data/public/states","minzoom":0,"maxzoom":22}

The cache delete endpoint allows you to delete any vector tile cache on the server.

This is a DELETE HTTP method endpoint.

In your request you have to pass the following.

{"database":"data","scheme":"public","table":"states"}

Cache Size endpoint allows you to determine the size of a vector tile cache for each table.

curl http://localhost:8000/api/v1/api/v1/tiles/cache_size

Example Response

[  {"table":"data_public_counties","size_in_gigabytes":0.004711238  },  {"table":"data_public_states","size_in_gigabytes":0.000034666  }]

The viewer allows to preview a tile dataset in a web map viewer.

For example, you can view the states table at/viewer/data/public/states. It will automatically zoom to the extent of the table.