koop

Turn GeoJSON into FeatureServices

Koop provides a flexible server for exposing 3rd party data sources (APIs) as both Feature Services and other data formats. This project is meant to provide a simple / plugable platform for experimenting with various data within the ArcGIS platform. Koop aims to provide a platform for accessing any API and making it easy to consume within the realm of Esri's geospatial web products.

Features

v1.0 January 2014

Data Adapters
- Gist / Github
- Socrata Open Data APIs
- ArcGIS Online
  - note: this is special case where koop can expose non-featureservices as actual feature services
API Caching
- Support simple data caching with automatic cache expiration via etags, shas, etc
Request caching
- should cache request and return 304
Feature Service Layer Queries
- Full support of http://resources.arcgis.com/en/help/arcgis-rest-api/
API Registration
- register hosts from Socrata and AGOL deploys

v1.1 March 2014 (planned)

Data formats
- PNG Tiles
- Vector Tiles
- Map Services
- UTF Grid
Support mixed geometry types
HTML Templates
Feature access via REST endpoints

Architecture

Dependencies

Node.js (version > 0.10.0)
MongoDB ( optional, but recommended for faster caching )

Installation

Koop is a Node.js project so you'll need Node.js, preferably a version > 0.10.0.

    # clone the repo
    git clone git@github.com:ArcGIS/koop.git

    # install the dependencies
    cd koop
    npm install

    // visit [http://localhost:1337](http://localhost:1337)

Running Koop

Koop run its own http server and you can start it like this (koop will use 1337 as its default port):

    // to run with a local cache (no persistent cache)
    node app.js 

    // to run with mongo (provide a valid mongodb connection string)
    node app.js --mongo=localhost:27017/koop  

    // to run on a non default port 
    PORT=1337 node app.js --mongo=localhost:27017/koop

Tests

Currently the tests use grunt to run them, and they depend on a running instance of koop. Once you have koop running issue:

    # install grunt if you dont have it
    sudo npm install -g grunt-cli

    # run the tests 
    grunt test

Demo + More Docs

We've deployed a sample server as a testbed / proof of concept to http://koop.dc.esri.com

Data Providers

Koop is now designed to expose 3rd party services as FeatureServices that are consumable within Esri products and services. Currently Koop has the following providers shipped by default:

gists
github
agol
socrata

Each provider resides in api/providers/

Defining a new provider

Each provider defines custom routes, a controller, and a model. Each of these uses module.exports to export an object (common js modules). Each is then fused into koop at start up time and becomes available within the server.

"Note": The name of the provider dir is used to define the name of the provider and its controller within koop.

Routes

Define custom routes in the "routes" index.js file:

        // defined in api/providers/sample/routes/index.js
 
        module.exports = {
          'get /sample': {
            controller: 'sample',
            action: 'index'
          }
        }

The above creates a /sample route that calls the index method on the sample controller ( defined in /api/providers/sample/controller/index.js ).

Controller

Defines the handlers to used to respond to routes

      module.exports = {
        // this tells koop to treat this provider like AGS service and show up at the root data provider endpoint 
        provider: false,

        // our index method to simple print text 
        index: function(req, res){
          res.send('Sample Providers, to make this a real one set provider true');
        }
  
      };

each method takes in a request and response property and needs to send something to the reponse.

Models

Should be used to interact directly with 3rd party services and databases
Models make the http requests to API and should hand back raw data to the controllers

Example URL Structure 1: Gists as a FeatureService

Example URL Structure 2: Github Repo as a FeatureService

http://koop.dc.esri.com/github/colemanm/hurricanes/fl_2004_hurricanes
http://koop.dc.esri.com/github/colemanm/hurricanes/fl_2004_hurricanes/FeatureServer
http://koop.dc.esri.com/github/colemanm/hurricanes/fl_2004_hurricanes/FeatureServer/0/query
Note: Repos can of course have directories, and this presents an issue with creating dynamic routes that match arbitrary paths in github. To sole this Koop will replace dashes with slashed in its github routes:
- http://koop.dc.esri.com/github/geobabbler/geodata/geojson-border_crossings/FeatureServer/0/query
- The above url would pull down this geojson file: https://github.com/geobabbler/geodata/blob/master/geojson/border_crossings.geojson

Feature Service Support

We'd like to have full feature service query support from any geojson data source. Currently the coverage is limited to the following params:

To see a full list of what koop will support in time visit http://resources.arcgis.com/en/help/arcgis-rest-api/

Caching

Koop uses either a local cache or a MongoDB instance to store data so that it doesnt flood external API with requests. This is helpful for avoiding API rate limits and general makes Koop faster (quick access to data). By default Koop will use a local hash to store data, but this is inefficient and doesnt persist across processes. To get around this Koop can use MongoDB which works well for non-relational data and has the added bonus of having geospatial query support.

Resources

Issues

Find a bug or want to request a new feature? Please let us know by submitting an issue.

Contributing

Esri welcomes contributions from anyone and everyone. Please see our guidelines for contributing.

Credit

Licensing

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.

A copy of the license is available in the repository's license.txt file.

[](Esri Tags: ArcGIS Web Mapping GeoJson FeatureServices) [](Esri Language: JavaScript)

wboykinm / koop