Backend examples for OpenBB Pro

Introduction

An OpenBB Pro Custom Backend is a versatile way to connect your data to widgets inside OpenBB Pro. Whether hosted internally or externally, this method provides a standardized structure that OpenBB Pro widgets can read and then display any data.

Note: Most of the examples provided use Python FastAPI due to our familiarity with the library, but the same could be done utilizing different languages.

The Main tenants are:

1. Data returned should be in JSON format (Note : you can utilize the "dataKey" variable in the widgets.json if you have nested JSON.)

Example JSON

```json
[
  {
    "ticker": "AAPL",
    "name": "Apple Inc.",
    "price": 150.5,
    "marketCap": 2500000000,
    "change": 1.25
  },
  {
    "ticker": "GOOGL",
    "name": "Alphabet Inc.",
    "price": 2800.75,
    "marketCap": 1900000000,
    "change": -0.75
  },
  {
    "ticker": "MSFT",
    "name": "Microsoft Corporation",
    "price": 300.25,
    "marketCap": 220000000,
    "change": 0.98
  },
]
```

2. An endpoint returning a widgets.json file : This file defines widget properties such as name, description, category, type, endpoint, and other information. Each widget will be defined in this file – You can find the format in any of the templates folder with a detailed definition below.

3. CORS Enabled : If hosting locally you must enable CORS.

4. Adding Authentication (optional) : If your backend requires authentication we offer the ability to set a query param or header when you connect to it through OpenBB Pro. These values are sent on every request when configured. If you require another method - please reach out to us.

Supported Integrations and Templates

Each Integration below has a folder which contains an example of different implementations - We recommend starting with the Table Widget Example.

Integration	Description
Table Widget	A simple table widget from a file or endpoint
Chart Widget	How to return a plotly chart or a built in chart
Markdown Widget	Markdown Widget and example with a parameter
Metric Widget	Showing a single metric

Advanced Examples	Description
Parameters Widget	Example of setting up widgets with parameters
Grouping Widgets	How to group widgets on the dashboard
Column and Cell Rendering	An example of widgets with custom column and cell rendering

Database Connection Examples	Description
ClickHouse	ClickHouse is an open-source column-oriented DBMS.
Supabase	Supabase is an open source Firebase alternative.
MindsDB	MindsDB is an open-source AI layer for existing databases.
ElasticSearch	Elasticsearch is a search engine based on the Lucene library.
ArticDB	Using ArticDB to add data to a widget.
Snowflake	Snowflake is a cloud-based data warehousing platform.

Getting Started

1. Go into the folder you want to run (we recommend the "Table Widget Example") and read the README.md file with instructions.

2. Run pip install -r requirements.txt

3. Run uvicorn main:app --port 5050 to start your backend.

4. Create a Custom Backend on OpenBB Pro with the link to your API URL (e.g., http://localhost:5050).

Code explained

main.py

This file is responsible for running the FastAPI with endpoints that will be consumed by OpenBB Pro.

• Enables cross-origin resource sharing (CORS) and configures it according to the domain where FastAPI is running and the Pro link.

• Initializes FastAPI with app = FastAPI()

• Ensures that there's a /widgets.json file that OpenBB Pro can use to configure the widgets configured

  Endpoint to fetch widgets.json file

  @app.get("/widgets.json")
  def get_widgets():
      """Widgets configuration file for OpenBB Pro"""
      file_path = "widgets.json"
      with open(file_path, "r") as file:
          data = json.load(file)
      return JSONResponse(content=data)

• Creates remaining endpoints that retrieve data that will be consumed by OpenBB Pro

widgets.json

This file contains the settings for all the widgets that the backend contains. Each dictionary within represents a widget with different configurations.

You must ensure that in your widgets.json you pass the three required fields - everything else is optional but allows for more configuration.

Also note that the key must be unique.

Example widgets.json file

{
  "financial_data": { // must be unique in your widgets.json
    "name": "Financial data", // required - Name of the Widget
    "description": "Financial data from the backend", // required - Description of the Widget
    "endpoint": "financial_data", // required - What endpoint to hit from the main.py file
  }
}

For more examples on what you can pass and setting up your own backend - you can head to our documentation at https://docs.openbb.co/pro.

Additional Configurations / Troubleshooting

HTTPS

Some browsers (Safari) or applications (Excel on Mac) require HTTPS to be enabled to fetch data from an API.

To enable HTTPS in your local environment, follow these steps:

1. Install mkcert.
2. cd into the backend you will be using, e.g. cd snowflake_python.
3. Run mkcert localhost 127.0.0.1 ::1. This will create localhost+2.pem and localhost+2-key.pem files in the current directory.
4. Run uvicorn main:app --port 5050 --ssl-keyfile=localhost+2-key.pem --ssl-certfile=localhost+2.pem --reload to start the server with HTTPS enabled.