jpop

jpop is a tomcat based REST service that will open a jsonl url resource and generate a population report from the contents. Once the application is started the service can be accessed via a web browser, curl, wget, etc..

Report contents

Data from the jsonl file will be summarized into a report with the following fields

totalPopulation - The sum of the populations of all citites
largestPopulation - The largest population of any city
mostPopulousCities - City with largest population.  If there are ties all cities are displayed
states - All the distinct states.

Report options

The report accepts two parameters

| option       | use                            | default value                                            |
|--------------|--------------------------------|----------------------------------------------------------|
| url          | url of jsonl datasource        | https://dl.dropboxusercontent.com/u/2436323/cities.jsonl |
| ignoreErrors | ignore parsing errors of jsonl | false                                                    |

jsonl format

Each row contains a json object containing the following fields:

city (String): The name of the city
state (String): The 2 digit state abbreviation
population (Integer): The population of the city

Example:

{"city": "New York", "state": "NY", "population": 8550405}
{"city": "Los Angeles", "state": "CA", "population": 3971883}

Build instructions

Git clone

jpop is housed in a GitHub repository. To clone the application create a directory of your choosing and run the following command (you must have git installed):

 git clone git@github.com:gudstrand/jpop.git

Gradle build

To build and launch the webserver cd into the jpop directory and run the following gradle command (mak sure to include the "w", it is not a typo!):

gradlew bootRun

This command will build and package the server, and launch it on port 8080 on the localhost.

Alternative

You can also build the application with the command

gradlew build

This command will build the application jar. That can be run with the following commmand

java -jar jpop-rest-service-0.1.0.jar

Using JPOP

The Jpop REST service accepts only one parameter, that is the url of the jsonl data source. If none is provided it will default to https://dl.dropboxusercontent.com/u/2436323/cities.jsonl

To access another url provide the parameters on the request line :

http://localhost:8080/population?url=https://dl.dropboxusercontent.com/u/2436323/cities.jsonl

Compressed resources

jpop can also access gzip compressed jsonl resources too if they have a .gz extension.

http://localhost:8080/population?url=https://dl.dropboxusercontent.com/u/7002771/allrecs.jsonl.gz

Web Report

You can also view an online population report here :

http://localhost:8080/popreport?url=https://dl.dropboxusercontent.com/u/7002771/allrecs.jsonl.gz

POST via curl

JPOP also accepts POST requests. Below are some examples using curl

Specify URL

curl --data "url=https://dl.dropboxusercontent.com/u/7002771/statecodetolong.jsonl" http://localhost:8080/population

ignoreErrors

curl --data "url=https://dl.dropboxusercontent.com/u/7002771/statecodetolong.jsonl&ignoreErrors=true" http://localhost:8080/population