koop

Turn data into FeatureServices

Koop provides a flexible server for exposing 3rd party data sources (APIs) as both Feature Services and other data formats (GeoJSON). 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.

Architecture

Dependencies

The following dependencies are needed in order to run Koop on your local machine / server:

Node.js (version > 0.10.0)
PostgreSQL / PostGIS - In PostgreSQL 9.3 you can create a PostGIS enabled database by executing CREATE EXTENSION postgis; inside an existing database.

Installation

clone the repo git clone git@github.com:Esri/koop.git
enter the koop project directory cd koop
install the node.js dependencies npm install

If npm install fails trying to install node-canvas (on a mac)

install xquartz - https://xquartz.macosforge.org/landing/
install cairo brew install cairo
Update the pkgconfig path export PKG_CONFIG_PATH=/usr/X11/lib/pkgconfig
try again to install node.js dependencies npm install

Configuration

Koop uses a config called /config/local.js to setup its database connection and data directories for caching data.

NOTE: it is crucial that you make the appropriate edits to your config/local.js file so that the values match your environment.

copy the example config file cp config/local.js.example config/local.js
edit config/local.js for your environment.

In particular you will need to:

Ensure that the specified logfile directory exists and you have write permissions on it.
Ensure that the PostGIS database configuration matches the host, port, user, password, and name of your database.
In order to use the Github and Gist providers you'll need to correctly set the "github_token" property to match your personal Github API token.

Running Koop

Koop runs its own http server and will use port 1337 by default. You can start koop in several ways (see below) and then visit http://localhost:1337

start the server with auto-reload via grunt:

grunt server

start the server with node:

node app.js

to run on a non default port

PORT=9999 node app.js

Tests

Currently the tests depend on a locally running instance of koop. Once you have koop running:

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)

jstopchick / koop