craigching / nextbus

NextBus Assignment

Table of Contents

• Overview
• Note to reveiwers
• Building
• Running
• System Test
• TODO

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Overview

In this programming assignment, I implement a client that consumes the REST-based API at http://svc.metrotransit.org to provide the arrival of the next bus given a route, direction, and stop. There are two versions of the client, a command line utility and a web user interface.

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Note to reviewers

This repository contains multiple projects. nextbus-core is the core of the project and provides a command line interface for requesting the next departure from a bus stop. The command line utility is documented below. nextbus-core is the most robustly implemented project. There are numerous unit tests as well as an exhaustive system test to prove the functionality of nextbus-core. The focus of review should be on the code implemented here.

There are also two stretch goals implemented in the projects nextbus-service and nextbus-docker. These projects are less robust as they were more ambitious with less time given for implementation and testing. Nevertheless, they are built on nextbus-core and provide fairly robust functionality. There is a hosted instance of these two projects on Amazon Web Services here. Please note that the UI is very minimal, but functional. I take full responsibility for any shortcomings associated with any of these projects!

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Building

In order to build, you need the following:

• A Java 8 JDK (http://www.oracle.com/technetwork/java/javase/downloads/jdk8-downloads-2133151.html)
• The Apache Maven build tool (https://maven.apache.org)
• A sane UNIX shell (bash or zsh maybe bash on cygwin for Windows)
• Optionally, you need docker to build nextbus-docker

This project was built using the following versions of the JDK:

% java -version
java version "1.8.0_161"
Java(TM) SE Runtime Environment (build 1.8.0_161-b12)
Java HotSpot(TM) 64-Bit Server VM (build 25.161-b12, mixed mode)

and Maven:

% mvn -version
Apache Maven 3.3.9 (bb52d8502b132ec0a5a3f4c09453c07478323dc5; 2015-11-10T10:41:47-06:00)
Maven home: /Users/cching/apps/maven/latest
Java version: 1.8.0_161, vendor: Oracle Corporation
Java home: /Library/Java/JavaVirtualMachines/jdk1.8.0_161.jdk/Contents/Home/jre
Default locale: en_US, platform encoding: UTF-8
OS name: "mac os x", version: "10.12.6", arch: "x86_64", family: "mac"

and zsh:

% zsh --version
zsh 5.2 (x86_64-apple-darwin16.0)

and Docker CE:

% docker version
Client:
 Version:      18.03.1-ce
 API version:  1.37
 Go version:   go1.9.5
 Git commit:   9ee9f40
 Built:        Thu Apr 26 07:17:20 2018
 OS/Arch:      linux/amd64
 Experimental: false
 Orchestrator: swarm

Server:
 Engine:
  Version:      18.03.1-ce
  API version:  1.37 (minimum version 1.12)
  Go version:   go1.9.5
  Git commit:   9ee9f40
  Built:        Thu Apr 26 07:15:30 2018
  OS/Arch:      linux/amd64
  Experimental: false

Once the JDK and Maven are correctly installed, the project can be built by executing (from the top-level directory):

% mvn clean install

This will build the project and run unit tests. If you don't want to install docker, you can build with the following command:

% mvn -pl "\!nextbus-docker" clean install

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Running

To run the command line program, make sure the project has built successfully. Then, you can run the nextbus.sh shell script from the root directory. The command-line utility supports two modes of operation. The first is as specified in the assignment:

% ./nextbus.sh <route> <stop> <direction>

For example:

% ./nextbus.sh "METRO Blue Line" "Target Field Station Platform 1" south
5 minutes

The other way to run it is with robust command-line options. This allows the user to get a list of routes, directions, and stops making it easier to debug and track down problems:

You may specify <route> <stop> <direction> or you may use the robust options below.

Option                Description
------                -----------
-?, -h, --help        show help
--direction <String>  A valid direction on the given route, one of south, east,
                        west, or north
--list                List routes, directions, or stops depending on given
                        arguments
--route <String>      A valid route
--stop <String>       A valid stop on the given route

For example:

% ./nextbus.sh --route "METRO Blue Line" --stop "Target Field Station Platform 1" --direction south
5 minutes

If you want to run the java dropwizard service, you can run it using the service.sh script from the root directory:

% ./service.sh

Assuming you don't have port conflicts with 8080 and 8081, you should then be able to access the UI from localhost:8080. If you built the docker service, you can start it with:

% ./docker-run.sh

This will start a docker container and the UI should be accessible from localhost:8080.

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System Test

There is an exhaustive system test that is disabled in the project. To run it, uncomment the two lines here and here then run mvn test or you can run it from within your IDE if desired.

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TODO

There is a simple emacs org mode file called TODO.org. I keep track of things that need doing there and check them off as I finish them.