From fdcde7d425ed371b7c886846526fc19b04abaf77 Mon Sep 17 00:00:00 2001
From: Bram Schoenmakers <me@bramschoenmakers.nl>
Date: Tue, 6 Aug 2024 06:12:12 +0200
Subject: [PATCH] Add CSV export

---
 README.org         |  3 ++-
 elfeed-export.el   | 34 ++++++++++++++++++++++++++++++++++
 elfeed-export.info | 15 ++++++++-------
 3 files changed, 44 insertions(+), 8 deletions(-)

diff --git a/README.org b/README.org
index 18001a2..af9b3ec 100644
--- a/README.org
+++ b/README.org
@@ -11,8 +11,9 @@ The following export formats are currently supported:
 
 | Format                  | Command                    |
 |-------------------------+----------------------------|
-| JSON                    | ~elfeed-export-to-json-file~ |
+| CSV                     | ~elfeed-export-to-csv-file~  |
 | Emacs Lisp Data (*.eld) | ~elfeed-export-to-lisp-file~ |
+| JSON                    | ~elfeed-export-to-json-file~ |
 
 Please note there is *no import functionality*. The goal is to have a (more or less) readable copy of your database. For a real backup, make a backup of ~/.elfeed instead.
 
diff --git a/elfeed-export.el b/elfeed-export.el
index b4d8bf2..52832c1 100644
--- a/elfeed-export.el
+++ b/elfeed-export.el
@@ -133,6 +133,34 @@ the entry should be exported."
   "Return the Lisp data string for all entries that should be exported."
   (prin1-to-string (elfeed-export--entries)))
 
+(defun elfeed-export--format-csv-value (value)
+  (let* ((string-value (if (listp value)
+                           (format "[%s]"
+                                   (mapconcat (lambda (elm)
+                                                (format "%s" elm))
+                                              value ";"))
+                         (format "%s" value)))
+         (escaped-string (string-replace "\"" "\"\"" string-value)))
+    (format "\"%s\"" escaped-string)))
+
+;;;###autoload
+(defun elfeed-export-to-csv ()
+  "Return the CSV string for all entries that should be exported."
+  (let* ((entries (elfeed-export--entries))
+         (columns (map-keys (seq-first entries))))
+    (concat
+     ;; header
+     (string-join columns ",")
+     "\n"
+     ;; data
+     (mapconcat (lambda (entry)
+                  (mapconcat (lambda (column)
+                               (elfeed-export--format-csv-value (alist-get column entry)))
+                             columns
+                             ","))
+                entries
+                "\n"))))
+
 ;;;###autoload
 (defun elfeed-export-to-json-file (path)
   "Write the JSON string to a file at PATH."
@@ -145,6 +173,12 @@ the entry should be exported."
   (interactive "F")
   (write-region (elfeed-export-to-lisp) nil path nil nil nil t))
 
+;;;###autoload
+(defun elfeed-export-to-csv-file (path)
+  "Write the CSV string to a file at PATH."
+  (interactive "F")
+  (write-region (elfeed-export-to-csv) nil path nil nil nil t))
+
 (provide 'elfeed-export)
 
 ;;; elfeed-export.el ends here
diff --git a/elfeed-export.info b/elfeed-export.info
index c079d2c..5b28c68 100644
--- a/elfeed-export.info
+++ b/elfeed-export.info
@@ -39,8 +39,9 @@ Emacs (https://github.com/skeeto/elfeed).
 
 Format                    Command
 ---------------------------------------------------------
-JSON                      ‘elfeed-export-to-json-file’
+CSV                       ‘elfeed-export-to-csv-file’
 Emacs Lisp Data (*.eld)   ‘elfeed-export-to-lisp-file’
+JSON                      ‘elfeed-export-to-json-file’
 
    Please note there is *no import functionality*.  The goal is to have
 a (more or less) readable copy of your database.  For a real backup,
@@ -162,12 +163,12 @@ configuration snippet:
 Tag Table:
 Node: Top87
 Node: Introduction406
-Node: Installation1092
-Node: Configuration1497
-Node: Customize export fields2231
-Node: Customize entry filters3328
-Node: By tag3740
-Node: By feed4214
+Node: Installation1150
+Node: Configuration1555
+Node: Customize export fields2289
+Node: Customize entry filters3386
+Node: By tag3798
+Node: By feed4272
 
 End Tag Table