ritherdon-archive/src/utils.lisp

(in-package #:cl-user)
(defpackage #:utils
  (:use #:cl
	#:caveman2
	#:log4cl
	#:app-constants)
  (:export #:i18n-load
           #:_
           #:parse-iso-date
	   #:request-params
	   #:string-is-nil-or-empty?
	   #:separate-files-in-web-request
	   #:set-alert
	   #:get-alert
	   #:get-and-reset-alert
	   #:checkbox-to-bool
	   #:asciify
	   #:slugify
	   #:get-image-dimensions
	   #:run-bash-command
	   #:create-thumbnail
	   #:create-timestamp-id)
  (:documentation "Utilities that do not depend on models."))

(in-package #:utils)

(defun asciify (string)
  (str:downcase (slug:asciify string)))

(defun slugify (string)
  "Turns a string of text into a slug."
  (str:downcase (slug:slugify string)))

(defun request-params (request)
  (loop :for (key . value) :in request
	:collect (let ((*package* (find-package :keyword)))
		   (read-from-string key))
	:collect value))

;; PORT CODE TO NO LONGER CALL THIS VERSION OF THE FUNCTION (MOVED TO VALIDATION PACKAGE).
(defun string-is-nil-or-empty? (string-to-test)
  "Tests to see if `STRING-TO-TEST' is empty of just whitespace.
This is essentially the 'IsNullOrWhiteSpace' function I use in C#. It
expands the 'empty string' check to include a check to see if there is
string with just a '(white) space' in it."
  (if (or (string= string-to-test " ")
	  (zerop (length string-to-test))
	  (null  string-to-test))
      t
      nil))

(defun separate-files-in-web-request (request &optional request-value)
  "Creates a new list of 'upload' files from a web `REQUEST'.
You will mostly use this for processing a multi-file upload (HTML)
form. The standard value for the 'name' attribute in (file) input tag
in the HTML form is `CONTENT-FILES' but you can use a different
name. Just specify it in this function's `REQUEST-VALUE' argument."
  (loop :for item :in request
	if (or (string= "CONTENT-FILES" (car item))
	       (string= request-value (car item)))
	  collect item))

(defun set-alert (message)
  "Sets the alert `MESSAGE' stored in session, provide info. to users.
The intention is store a `MESSAGE' across a redirect during a HTTP
POST request."
  (setf (gethash :alert ningle:*session*) message))

(defun get-alert ()
  "Get alert message from session data."
  (gethash :alert ningle:*session*))

(defun get-and-reset-alert ()
  "Returns the `ALERT' message and clears its content from the session hash."
  (let ((message (get-alert)))
    (set-alert nil)
    message))

(defun checkbox-to-bool (value)
  "Converts a HTML Checkbox `VALUE' to a Boolean.
The `VALUE' will either be 'on' or 'off'. 'Boolean' in this instance
is assuming you are using SQLite and need to convert `VALUE' to an
integer/number. If you are needing a traditional Boolean value, DO NOT USE
THIS FUNCTION."
  (cond ((or (string= "checked" value) (string= "on" value)) +true+)
	((or (string= "off" value) (null value)) +false+)
	((null value) +false+)))

(defun get-image-dimensions (filepath)
  "Uses Image Magick (via Bash) to get the resolution of an image as 'WxH'.
The `FILEPATH' must be already merged with
`ritherdon-archive.config::*application-root*' before you call this function."
  (let* ((command
	   (format nil "identify -format \"%wx%h\" ~a" filepath))
	 (out-message (uiop:run-program command :output :string
						:ignore-error-status t
						:error-output :string)))
    out-message))

(defun run-bash-command (command)
  "Runs the Bash command."
  (uiop:run-program command :output :string
			    :ignore-error-status t
			    :error-output :string))

(defun create-thumbnail (storage-sub-directory file-name)
  "Runs a Bash command to convert a file to a thumbnail  in /storage/media dir.
The file is reduced to 512x512 pixels if bigger than that. A new file
is then created with a 'thumbnail-' pre-fix. This process relies on
Image Magick. So, it must be installed on the system for this function
to operate properly."
  (run-bash-command
  (format nil "convert ~a -resize 512x512\\> ~a"
	  (storage:file-exists-p "" storage-sub-directory file-name)
	  (storage:make-path "" storage-sub-directory
			     (format nil "thumbnail-~a" file-name)))))

(defun create-timestamp-id ()
  "Creates a integer based on time the function is called, in YYYYMMDD format."
  (multiple-value-bind
	(second minute hour day month year)
      (get-decoded-time)
    (format nil "~d~2,'0d~d~2,'0d~2,'0d~2,'0d" year month day hour minute second)))