Project Name

DelSurProps - backend

About the project

What it is

An API that connects the React frontend with a PostgreSQL database.

What it does

1. GET: Filters real state objects based on the input the API receives and returns the output back to the frontend.
2. DELETE - POST: Deletes and Creates real state objects based on the frontend input.

Link

• Front end demo: https://endearing-melomakarona-8df72e.netlify.app
• Video of the working app w/ backend and frontend: https://youtu.be/kzu_LFJki7s
• delsurprops.com.ar (site shut down as per client request)

Front end

https://github.com/Matias-Ramos/Inmobiliaria

Full stack diagram

Challenges on this project:

• First time writting a Golang API.
• Learnt and implemented JWT for session authentication.
• SQL query generation on the backend.
• REST API architecture.

Code

Language

Golang

Program structure

I won't go through all the program structure, but only through the three files that have the biggest complexity, as I find the overall perspective quite helpful to understand the logic in them. Remember that further details are written as comments in the respective files:

post.go

• PostData()
  • generateInsertQuery()
    • convertToLowerCase()
    • parseToSqlSyntax()

get.go

• GetDBdata()
  • generateGetQuery()
    • handleLocationField() - due to query syntax uniqueness, a specific method was required.
    • handleBuildingStatusField() - due to query syntax uniqueness, a specific method was required.
    • handleCommonField()
      • includeNullValues()
  • initBuildingType()

auth

Endpoints

GET

• http://localhost:8080/api/venta_inmuebles
• http://localhost:8080/api/alquiler_inmuebles
• http://localhost:8080/api/emprendimientos

POST

• http://localhost:8080/admin/post/{category}

DELETE

• http://localhost:8080/admin/delete/{category}

AUTH

• http://localhost:8080/admin/jwt

Queries

• ?location=string
• ?price_init=integer / ?price_limit=integer
• ?env_init=nullInteger / ?env_limit=nullInteger
• ?bedroom_init=nullInteger / ?bedroom_limit=nullInteger
• ?bathroom_init=nullInteger / ?bathroom_limit=nullInteger
• ?garage_init=nullInteger / ?garage_limit=nullInteger
• ?total_surface_init=nullInteger / ?total_surface_limit=nullInteger
• ?covered_surface_init=nullInteger / ?covered_surface_limit=nullInteger
• ?building_status= in_progress-or-pozo/pozo/in_progress

*nullInteger = accepts both null and integer.

Running the project

1. Clone the project and run "go run main.go" or "go run ." in the IDE terminal.

Environment setup

2. Create a .env file in the root directory of the project with the following environment variables:

• PGS_USER="new_user"
• PGS_PWD="secure777"
• PGS_DB_NAME="Inmobiliaria_BD"
• API_KEY="1234"
• JWT_SECRET="super-secret-auth-key"

Database setup

3. Create a database with a user, password and database name as shown in the previous point. As for the tables:

common fields for all tables:

• id - bigint notnull
• location - text notnull
• price - integer notnull
• env - smallint
• bedrooms - smallint
• bathrooms - smallint
• garages - smallint
• images - text[] notnull
• link_ml - text
• link_zonaprop - text
• link_argenprop - text

venta_inmuebles:

• currency - text

alquiler_inmuebles:

• total_surface - smallint
• covered_surface - smallint

emprendimientos:

• total_surface - smallint
• covered_surface - smallint
• pozo - boolean notnull
• in_progress - boolean notnull

POST

4. Hit "localhost:8080/admin/jwt" with a get request. Inside the header, add a key value pair "Access":1234. You will receive a token, save it.

5. Hit "localhost:8080/admin/alquiler_inmueble" (note that the category is singular, unlike the database name that is plural) with a post request.
   Inside the header, add a key value pair "Authentication": jwtToken, being jwtToken the value you saved in the previous step.
   Inside the body, this is an example of a valid value to send in JSON format: {"location":"1","price":"2","currency":"usd","env":"3","bedrooms":"4","bathrooms":"5","garages":"6","link_ml":"7","link_zonaprop":"8","link_argenprop":"9","image_links":["10","11"]}

DELETE

6. Hit "localhost:8080/admin/alquiler_inmuebles".
   Inside the header, add a key value pair "Authentication": jwtToken, being jwtToken the value you saved in the previous step.
   Inside the body, this is an example of a valid value to send in JSON format: {"buildingId": 1628372893729}
   Note that in order to know the ID you can either check the database, or use the Get request that will be shown next.

GET

7. Hit "localhost:8080/admin/alquiler_inmuebles".
   No query params will retrieve all the records.
   The possible queries may be find in the previous section "Queries", but here is an example:
   /alquiler_inmuebles?location=Villa+Crespo&price_init=10000&price_limit=20000&env_init=1&env_limit=7&bedroom_init=1&bedroom_limit=7&bathroom_init=1&bathroom_limit=7&garage_init=0&garage_limit=7