mbt

Documentation

Overview

Diglet is a set of geospatial tools focused around rendering large feature sets efficiently.

Index

• Variables
• func FeatureTiles(f *geo.Feature) (tiles []ts.Tile)
• func MvtAdapter(f *geo.Feature, t ts.Tile) (a *mvt.Feature)
• func ShapeTiles(shp *geo.Shape) (tiles []ts.Tile)
• type CsvSource
  • func NewCsvSource(path string, filter []string, delimiter string, fields GeoFields) *CsvSource
  • func (c *CsvSource) Publish(workers int) (features chan *geo.Feature, err error)
• type FeatureSource
• type GeoFields
  • func (g GeoFields) HasCoordinates() bool
  • func (g GeoFields) HasShape() bool
  • func (g GeoFields) Validate() bool
• type GeojsonSource
  • func NewGeojsonSource(path string, filter []string) *GeojsonSource
  • func (gj *GeojsonSource) Publish(workers int) (features chan *geo.Feature, err error)
• type Tiles
  • func InitTiles(mbtpath string, upsert bool, desc string, extent uint) (tiles Tiles, err error)
  • func (t Tiles) Build(source FeatureSource, layerName string, zmin, zmax int) (err error)

Variables

var (
	CsvExt     = "csv"
	GeojsonExt = "geojson"
)

var Cmd = cli.Command{
	Name:        "mbt",
	Aliases:     []string{"build"},
	Usage:       "Builds an mbtiles database from the input data source",
	Description: "Builds an mbtiles database from the given format",
	ArgsUsage:   "input_source",
	Action: func(c *cli.Context) {

		out := c.String("output")
		desc := c.String("desc")
		layer := c.String("layer-name")
		zmin := c.Int("min")
		zmax := c.Int("max")
		extent := uint(c.Int("extent"))
		upsert := c.Bool("upsert")
		force := c.Bool("force")

		if len(c.Args()) == 0 || out == "" {
			util.Die(c, "input_source & --out required")
		} else if zmax < zmin || zmin < 0 || zmax > 23 {
			util.Die(c, "--max > --min, --min > 0 --max < 24 not satisfied")
		}

		source, err := getSource(c)
		util.Check(err)
		if force {
			os.Remove(out)
		}
		tiles, err := InitTiles(out, upsert, desc, extent)
		util.Check(err)
		err = tiles.Build(source, layer, zmin, zmax)
		util.Check(err)

		file, _ := os.Open(out)
		defer file.Close()
		stat, _ := file.Stat()
		exp := float64(stat.Size()) / float64(1<<20)
		util.Info("%s was successfully caught!", out)
		util.Info("Diglet gained %f MB of EXP!", exp)
	},
	Flags: []cli.Flag{
		cli.StringFlag{
			Name:  "o, output",
			Usage: "REQUIRED: Path to write mbtiles to",
		},
		cli.StringFlag{
			Name:  "input-type",
			Value: "sniff",
			Usage: "Type of input files, 'sniff' will pick type based on the extension",
		},
		cli.BoolFlag{
			Name:  "f, force",
			Usage: "Remove the existing .mbtiles file before running.",
		},
		cli.BoolFlag{
			Name:  "u, upsert",
			Usage: "Upsert into mbtiles instead of replacing.",
		},
		cli.StringFlag{
			Name:  "layer-name",
			Value: "features",
			Usage: "Name of the layer for the features to be added to",
		},
		cli.StringFlag{
			Name:  "desc, description",
			Value: "Generated from Diglet",
			Usage: "Value inserted into the description entry of the mbtiles",
		},
		cli.IntFlag{
			Name:  "extent",
			Value: 4096,
			Usage: "Extent of tiles to be built. Default is 4096",
		},
		cli.IntFlag{
			Name:  "max, max-zoom",
			Value: 10,
			Usage: "Maximum zoom level to build tiles for",
		},
		cli.IntFlag{
			Name:  "min, min-zoom",
			Value: 5,
			Usage: "Minimum zoom level to build tiles from",
		},
		cli.StringFlag{
			Name: "filter",
			Usage: "Only include fields keys in this comma delimited list.\t" +
				"EXAMPLE --filter name,date,case_number,id\t" +
				"NOTE all fields are lowercased and non-word chars replaced with '_'",
		},
		cli.StringFlag{
			Name:  "csv-lat",
			Usage: "Column containing a single longitude point",
		},
		cli.StringFlag{
			Name:  "csv-lon",
			Usage: "Column containing a single longitude point",
		},
		cli.StringFlag{
			Name: "csv-shape",
			Usage: "Column containing shape in geojson-like 'coordinates' form.\t" +
				"Does not support multi-geometries",
		},
		cli.StringFlag{
			Name:  "csv-delimiter",
			Value: ",",
		},
	},
}

var CoverZoom = 18

CoverZoom sets the zoom level for flat coverings This is a global b/c it could go away if a dynamic cover is implemented

Functions

func FeatureTiles

func FeatureTiles(f *geo.Feature) (tiles []ts.Tile)

FeatureTiles returns a list of tiles that cover the feature at CoverZoom level Dups are not checked for, so they can exist

func MvtAdapter

func MvtAdapter(f *geo.Feature, t ts.Tile) (a *mvt.Feature)

MvtAdapter populates an mvt feature from a diglet geo feature

func ShapeTiles

func ShapeTiles(shp *geo.Shape) (tiles []ts.Tile)

Shape tiles returns a list of tiles that cover a shape at CoverZoom level

Types

type CsvSource

type CsvSource struct {
	// contains filtered or unexported fields
}

func NewCsvSource

func NewCsvSource(path string, filter []string, delimiter string, fields GeoFields) *CsvSource

func (*CsvSource) Publish

func (c *CsvSource) Publish(workers int) (features chan *geo.Feature, err error)

type FeatureSource

type FeatureSource interface {
	Publish(workers int) (chan *geo.Feature, error)
}

type GeoFields

type GeoFields map[string]string

func (GeoFields) HasCoordinates

func (g GeoFields) HasCoordinates() bool

func (GeoFields) HasShape

func (g GeoFields) HasShape() bool

func (GeoFields) Validate

func (g GeoFields) Validate() bool

type GeojsonSource

type GeojsonSource struct {
	// contains filtered or unexported fields
}

func NewGeojsonSource

func NewGeojsonSource(path string, filter []string) *GeojsonSource

func (*GeojsonSource) Publish

func (gj *GeojsonSource) Publish(workers int) (features chan *geo.Feature, err error)

type Tiles

type Tiles struct {
	// contains filtered or unexported fields
}

func InitTiles

func InitTiles(mbtpath string, upsert bool, desc string, extent uint) (tiles Tiles, err error)

func (Tiles) Build

func (t Tiles) Build(source FeatureSource, layerName string, zmin, zmax int) (err error)