Safe Sale

Full craigslist ad showing recommended locations
Showing safest locations
Configuring the app through chrome

Inspiration

We wanted to make a small impact towards harassment in Vancouver. The four of us have used online classifieds before and knowing how nerve-racking it can be buying from a stranger, decided we'd help others by building a tool / application.

What it does

Safe Sale is a chrome extension that runs whenever you are viewing a product on craigslist. When a seller has specified a location to pickup, it will retrieve a list of safest locations to complete the transaction based on Vancouver RCMP's crime and safety statistics.

How we built it

We built the application into two separate modules. The first module is the backend API running on NodeJS, ExpressJS, and CockroachDB that interfaces with Google Maps API and Google Directions. After receiving a incoming request for safe locations, the backend will determine the closest locations with the maximum security also taking into account whether the user wants to commute via transit, walking, or driving. The second module is the chrome extension that is build using jQuery, MustacheJS and Google Chrome API. It injects code into craigslist ads that have a location set.

Challenges we ran into

Finding a good data source to cross reference crime and safety statistics. We also had no experience with cockroachdb and how to configure/set it up to use it with our NodeJS backend. Lastly, Google API has a limit on each token key, which got very frustrating while trying to test because Google doesn't have visible stats on how much you're used the token.

Accomplishments that we're proud of

Most of us had no web experience, so we're very proud to have build an app that uses many different web technologies and manage to communicate / work together. For some of us it is our first hackathon and we're proud to have made it through the night.

What we learned

We're learnt how to build more advanced chrome extensions that are able to make external requests, as well as be able to integrating a foreign database (cockroachdb) into our existing codebase.

What's next for Safe Sale

Create extensions for other browsers so that we don't leave anyone out.

Built With

Submitted to

nwHacks 2017

Created by

I worked on the Frontend Chrome extension that injects data into each Craigslist Ad. I also made sure that it made requests to the Backend and displayed any returned data correctly. Lastly, I dabbled in AWS to install and configure the master node for CockroachDB.

Anthony Smith
I worked on the back end of the system and gathered the statistics that we used. I learned a lot about the Google APIs that we used, as well as exposure to Cockroachdb.

Joe Tsui
I worked on the backend with Node.js. Also helped with data aggregation using python

Brandon Chong
I worked on the front end chrome extension, and assisted with some javascript injection of html code. Additionally, I also helped with styling the html injection into the Craigslist page.

Steven Shih

Updates

Anthony Smith started this project — Mar 19, 2017 03:31 PM EDT

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