Surge

Increase price as demand increases.

Features!

• User management (create, update, login)
• Rule management (threshold, request pairs)
• Price coefficient calculation

Tech

• Go - an open source programming language that makes it easy to build simple, reliable, and efficient software.
• Gin - a web framework written in Go (Golang).
• Gorm - The fantastic ORM library for Golang.
• OpenStreetMap - OpenStreetMap is the free wiki world map.
• PostgreSQL - PostgreSQL is a powerful, open source object-relational database system.
• PostGIS - PostGIS is a spatial database extender for PostgreSQL.
• Docker - for containerization.
• Logrus - Logrus is a structured logger for Go (golang), completely API compatible with the standard library logger.
• JWT - JSON Web Tokens are an open, industry standard RFC 7519 method for representing claims securely between two parties.
• Swagger - Simplify API development for users, teams, and enterprises with the Swagger open source and professional toolset.

How to run

Surge requires Docker and docker-compose to run.

$ git clone https://github.com/mhmd-bb/snapp-surge.git
$ cd snapp-surge
$ cp sample.env .env
$ cp ./osm-export/sample.env ./osm-export/.env
$ docker-compose up -d --build

Note

If you have timeout problem while downloading project dependencies use a VPN. (Sanctions...)

How to use

• After all services are up and running you can open http://localhost:8080/docs/index.html to see Swagger documentation.
• A Default user is created for you on application startup (you can change the user pass in .env file) so you can login.
• Don't forget to create rules (threshold, coefficient pairs).

You can easily use the Swagger Documentation; But I'm providing some curl commands as well:

User

Login:

$ curl -X POST "http://localhost:8080/users/login" -H  "accept: application/json" -H  "Content-Type: application/json" -d "{  \"password\": \"admin\",  \"username\": \"admin\"}"

Update Password:

$ curl -X PATCH "http://localhost:8080/users/password" -H  "accept: application/json" -H  "Authorization: Bearer {Your Token}" -H  "Content-Type: application/json" -d "{  \"password\": \"admin\"}"

Create New User:

$ curl -X POST "http://localhost:8080/users/register" -H  "accept: application/json" -H  "Authorization: Bearer {Your Token}" -H  "Content-Type: application/json" -d "{  \"password\": \"mohammad\",  \"username\": \"mohamamd\"}"

Rule

Get All Rules:

$ curl -X GET "http://localhost:8080/rules" -H  "accept: application/json" -H  "Authorization: Bearer {Your Token}"

Create New Rule:

$ curl -X POST "http://localhost:8080/rules" -H  "accept: application/json" -H  "Authorization: Bearer {Your Token}" -H  "Content-Type: application/json" -d "{  \"coefficient\": 1.1,  \"threshold\": 10}"

Delete Rule:

$ curl -X DELETE "http://localhost:8080/rules/1" -H  "accept: application/json" -H  "Authorization: Bearer {Your Token}"

And most importantly:

Ride Request which returns coefficient and increases district request counter:

$ curl -X POST "http://localhost:8080/surge/ride" -H  "accept: application/json" -H  "Content-Type: application/json" -d "{  \"lat\": 51.13199462890625,  \"lon\": 35.73425097869431}"

How the project works

How the map data is collected and stored:

• District Polygons of Tehran city are exported using overpass-turbo with geojson format and stored in osm-export folder.
• As you start the services using docker-compose, the gdal service exports the geojson file to PostGIS.

This way i can do spatial queries on the database and find the requested location's district.

How request counters are stored:

Instead of reseting the counter of a district every two hours and losing data on each reset i used the idea below:

The overal idea is that we have a moving window on small buckets (like a 2 hour Moving window on 10 minute Buckets).

Each Bucket has:

• counter
• expiration time (10 minutes for example)
• creation date
• district id

When a district's Bucket expires a new Bucket is created with counter value of 1.

The Moving window sums all Bucket counters of a district (in last 2 hours for example). This way we can have count of requests in the last two hours with +-10 minute accuracy.