npm package discovery and stats viewer.

Discover Tips

  • General search

    [free text search, go nuts!]

  • Package details

    pkg:[package-name]

  • User packages

    @[username]

Sponsor

Optimize Toolset

I’ve always been into building performant and accessible sites, but lately I’ve been taking it extremely seriously. So much so that I’ve been building a tool to help me optimize and monitor the sites that I build to make sure that I’m making an attempt to offer the best experience to those who visit them. If you’re into performant, accessible and SEO friendly sites, you might like it too! You can check it out at Optimize Toolset.

About

Hi, 👋, I’m Ryan Hefner  and I built this site for me, and you! The goal of this site was to provide an easy way for me to check the stats on my npm packages, both for prioritizing issues and updates, and to give me a little kick in the pants to keep up on stuff.

As I was building it, I realized that I was actually using the tool to build the tool, and figured I might as well put this out there and hopefully others will find it to be a fast and useful way to search and browse npm packages as I have.

If you’re interested in other things I’m working on, follow me on Twitter or check out the open source projects I’ve been publishing on GitHub.

I am also working on a Twitter bot for this site to tweet the most popular, newest, random packages from npm. Please follow that account now and it will start sending out packages soon–ish.

Open Software & Tools

This site wouldn’t be possible without the immense generosity and tireless efforts from the people who make contributions to the world and share their work via open source initiatives. Thank you 🙏

© 2024 – Pkg Stats / Ryan Hefner

@carto/cartonik

v0.9.1

Published

Render maps with @carto/mapnik

Downloads

136

Readme

Cartonik :earth_africa:

CircleCI

Render maps with @carto/mapnik

:rocket: Features

  • Render tiles from a Mapnik XML
  • Support several formats: png, jpeg, grid.json, mvt, etc..
  • Support traditional mapnik datasources: shape, postgis, gdal, ogr, etc..
  • Render static images from tiles based on center (long, lat) or bounding box (east, south, west, north) coordinates.
  • Optimized for high-performance services

:package: Installation

Cartonik requires Node.js 12

npm install @carto/cartonik

:globe_with_meridians: Render tiles

const { rendererFactory } = require('@carto/cartonik')

const renderer = rendererFactory({ xml: '<Map>...</Map>' })
const [ format, z, x, y ] = [ 'png', 0, 0, 0 ]

const tile = await renderer.getTile(format, z, x, y)

:computer: Usage: rendererFactory(options)

const options = { ... }
const renderer = rendererFactory(options)

:triangular_ruler: Renderer options

  • type: string (either raster or vector, default raster). Whether the renderer aims to render Mapnik Vector Tiles or traditional raster formats (png, utf).
  • xml: string (required). The Mapnik XML configuration.
  • base: string. Path to the folder where the datasource files are (e.g. shapefiles).
  • strict: boolean (default false). Enables mapnik strict mode.
  • bufferSize: number (default 256). Extra space, in pixels, surrounding the map size being rendered. This allows you to have text and symbols rendered correctly when they overlap the image boundary.
  • poolSize: number (default os.cpus().length). Max number of preloaded maps available for rendering.
  • poolMaxWaitingClients: number (default 32). Max number of waiting clients to acquire one of the preloaded maps.
  • tileSize: number (default 256). Size of the tile in pixels.
  • limits: object.
    • render: number (default 0 = disabled). Time in milliseconds to wait for the renderer to return a tile.
  • metrics: boolean (default false). Configure @carto/mapnik to gather statistics about rendering performance.
  • variables: object. A key-value dictionary to customize map configuration at render-time. Placeholders defined in xml (e.g. <PolygonSymbolizer fill="@water"/>) will be replaced with the values defined here (e.g. { water: 'blue' }).

Raster renderer options (type = raster)

  • metatile: number (default 2). The number of tiles included in a metatile. One metatile generates a group of images at once in batches before separating them into the final tiles - this improves efficiency in various ways.
  • metatileCache: object.
    • timeout: number (default 1 minute). When the timeout fires, it removes the cached tiles.
    • deleteOnHit: boolean (default false). Removes the cached tile after delivered.
  • scale: number (default 1). Multiplier to scale up size-related properties of symbolizers.
  • resolution: number (default 4). When format = utf, the factor to scale down the tile size.

Vector renderer options (type = vector)

  • gzip: boolean (default true). Compression method used to encoding a vector tile.

:mag: Get information about the renderer

const { rendererFactory } = require('@carto/cartonik')

const renderer = rendererFactory({ xml: '<Map>...</Map>' })

const stats = renderer.getStats()

console.log(stats)
//  Map { 'cache.png' => 1, 'pool.count' => 2, 'pool.used' => 1, 'pool.unused' => 1, 'pool.waiting' => 0 }

:fireworks: Static images (previews)

const { preview, rendererFactory } = require('@carto/cartonik')

const renderer = rendererFactory({ xml: '<Map>...</Map>' })

const { image } = await preview({
    center: {
        lng: -3.68529754,
        lat: 40.40197212
    },
    dimensions: {
        width: 200,
        height: 200
    },
    getTile: async function (format, x, y, z) {
        const { buffer } = await renderer.getTile(format, z, x, y)
        return { buffer }
    }
})

:computer: Usage: preview(options)

const options = { ... }
const renderer = preview(options)

:triangular_ruler: Preview options

  • getTile: function (required). Function to retrive the required tiles to build the preview image.
  • bbox: object. The bounding box for the west, south, east, and north coordinates of the requested area.
    • west: number. Longitude coordinate.
    • south: number. Latitude coordinate.
    • east: number. Longitude coordinate.
    • north: number. Latitude coordinate.
  • center: object. Point where the preview is centered. This option must be used along dimensions option.
    • lng: number. Long coordinate.
    • lat: number. Latitude coordinate.
  • dimensions: object. Preview's size in pixels. This options must be defined along center option and will be multiplied by scale to keep the resolution.
    • width: number.
    • heigth: number.
  • zoom: number default 0. The z cordinate, x and y will be calculated based on either bbox or center coordinates.
  • scale: number [1-4], default 1. Resolution (scale: 1 is 72dpi, scale: 4, is 288dpi).
  • format: string either png or jpg, default png.
  • quality: number. When used with jpg format, accepts 1-100 and defaults to 80. When used with png format, accepts 2-256 (# of colors to reduce the image to) and defaults to null.
  • limit: number default 19008. Max width or height of requested image in pixels. Default is 19008.
  • tileSize: number default 256. Size of tiles used in getTile function.
  • concurrency: number default 32. Number of concurrent calls to getTile. Useful to avoid map-pool exhaustion. Ideally, should match with poolSize (os.cpus().length) + poolMaxWaitingClients (32).

:1234: Versioning

We use SemVer for versioning. For the versions available, see the tags on this repository.

:busts_in_silhouette: Contributors

:page_with_curl: License

This project is licensed under the BSD 3-clause "New" or "Revised" License - see the LICENSE file for details.