Generate CSVs dynamically with Jinja

Creating Comma-Separated Values (CSV) files is a common requirement in various applications. Jinja templating offers a simple and efficient way to generate CSV files dynamically. This article demonstrates how to create a CSV file from data using Jinja templates and how to set headers dynamically, providing a versatile solution for your data processing needs.

Create a CSV File with Jinja

To create a CSV file using Jinja, follow these steps:

1. Prepare Your Data: First, organize your data into a list of dictionaries. Each dictionary represents a row in the CSV, with keys representing column headers and corresponding values.

   {%- set csv_data = [
       {
       "name": "rewsty",
       "address": "123 rewsty lane",
       "timezone": "EST"
       }
   ] -%}

2. Generate CSV Headers Dynamically: Use Jinja filters to dynamically set the CSV headers. In the provided example, the fieldnames parameter is populated with the keys from the first dictionary in the csv_data list.

   {{- csv_data | csv(fieldnames = csv_data[0].keys() | list) -}}

   Here, csv_data[0].keys() | list generates a list of keys from the first dictionary in csv_data, ensuring dynamic header generation.

Example output

The above Jinja code will generate a CSV output similar to the following:

name,address,timezone
rewsty,123 rewsty lane,EST

Benefits of dynamic CSV generation with Jinja

1. Flexibility: Dynamic header generation allows you to adapt your CSV format based on the structure of your data.

2. Simplicity: Jinja's concise syntax simplifies the process of transforming data into CSV format.

3. Automation: As your data changes, Jinja can adapt the CSV headers automatically, streamlining your workflow.