🅛 Common Lisp Potential

Abstract

This is an excuse to be a nerd and to sketch out a modern database written in CommonLisp.

It needs to be easy to operate. Store both .csv files and rich media. A pipeline that batch processes weekly data analytics into a .pdf file. Also, it needs to have basic backups and redundancies. To do this, I fork L Source to begin dev.

Introduction

The realm of programming has witnessed evolution of numerous languages, each boasting unique features and capabilities. I've had a sweet spot for LISP. Any honest programmer, engineer, or builder will tell you choosing the right tools for the job can be a battle.

But if you end up in a committe meeting about which hammer to use and the constrcution project is two months behind. Then your up-sh*t-creek without a paddle.

Database Design

Designing a database in Common Lisp, given the requirements such as ease of operation, handling .csv files and rich media, batch processing for weekly data analytics, and implementing basic backups and redundancies, involves several steps and considerations.

In Common Lisp, custom data structures are pivotal for representing the data from CSV files. For instance, when dealing with web analytics data, a structure might be defined with fields like date, visits, and bounceRate. Utilizing Lisp's defstruct or class for an object-oriented approach allows for the creation of these structures.

Parsing CSV files in Common Lisp necessitates functions that can convert the data into the defined Lisp data structures. Given that Common Lisp does not have a built-in CSV parser, external libraries like cl-csv can be employed to facilitate this task.

For storing rich media, considering the file system storage or integration with external storage solutions is essential. In this setup, the database would store references, such as file paths or URLs, to these media files.

When it comes to the database backend, Common Lisp requires interfacing with an external database since it doesn't have its own database system. Libraries like CL-SQL enable connections to SQL databases.

;; Connecting to a SQL database
(clsql:connect '("host" "database" "user" "password") :database-type :postgres)

;; Function to query data from the database
(defun get-data-from-db (query)
  (clsql:query query))

;; Example usage
(let ((data (get-data-from-db "SELECT * FROM analytics_table")))
  ;; Process and use the data
  )

Analytics

Batch processing for analytics is another crucial aspect. This involves implementing functions to aggregate and analyze the data on a weekly basis, leveraging Lisp's data manipulation capabilities. Generating PDF reports can be achieved through libraries like CL-PDF.

;; Importing CL-PDF package
(use-package :cl-pdf)

;; Function to generate a PDF report
(defun generate-pdf-report (data filename)
  (with-open-file (stream filename 
                          :direction :output 
                          :if-exists :supersede)
    (pdf:with-document ()
      (pdf:with-page ()
        ;; Add content to the page using data
        (pdf:draw-text (pdf:get-font "Helvetica" 12) 
                       50 800 
                       (format nil "Report Generated: ~A" (get-universal-time)))
        ;; Further data processing and PDF generation logic goes here
        ))
    (pdf:write-document stream)))

Ensuring data safety and continuity, the implementation of a system for regular database backups is necessary. Automating this process with Lisp scripts could enhance efficiency. For redundancies, a replicated database or a failover system should be in place.

Script

;; Assuming use of CL-SQL for database interactions
(use-package :cl-sql)

;; Function to connect to the database
(defun connect-to-db ()
  (clsql:connect '("host" "database" "user" "password") :database-type :postgres))

;; Function to perform the backup
(defun backup-database ()
  (let ((backup-command "pg_dump ...")) ;; Replace with actual backup command
    (uiop:run-program backup-command)))

;; Function to check and update replication or failover status
(defun check-replication-status ()
  ;; Code to check the status of replication/failover system
  )

;; Main function to automate the backup process
(defun automate-backup ()
  (connect-to-db)
  (backup-database)
  (check-replication-status)
  ;; Additional logic for storing backup and handling errors
  )

;; Running the backup automation
(automate-backup)

Front-end

Although Common Lisp handles backend processing, integrating with Re-tool for the frontend requires the development of an API in Lisp. This API would facilitate CRUD operations on your database by Re-tool.

For connecting Lisp to Re-tool, you would typically create a web server in Lisp that exposes an API. This API can be called from Re-tool to perform CRUD operations. Here's a basic example using the Hunchentoot web server:

;; Importing Hunchentoot
(use-package :hunchentoot)

;; Defining a simple handler for a GET request
(define-easy-handler (get-data :uri "/getdata") ()
  ;; Fetch data from the database or perform some logic
  (let ((data (get-some-data)))
    (setf (content-type*) "application/json")
    (format nil "~a" (convert-data-to-json data))))

;; Running the server
(setf hunchentoot:*dispatch-table* 
      '((t . get-data)))
(hunchentoot:start (make-instance 'hunchentoot:acceptor :port 8080))

Conclusion

Testing and documentation to ensure maintainability.

L Source