#+title: elfeed-export
#+author: Bram Schoenmakers
#+export_file_name: elfeed-export.info
#+property: header-args:elisp :results none :exports code

* Introduction

/elfeed-export/ exports your feed entries from the [[https://github.com/skeeto/elfeed][elfeed RSS reader for Emacs]].

The following export formats are currently supported:

| Format                  | Command                    |
|-------------------------+----------------------------|
| 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.

* Installation

/elfeed-export/ is not on MELPA, therefore clone the directory first:

: git clone https://codeberg.org/bram85/elfeed-export.git

Then configure the package as follows:

#+begin_src elisp
  (use-package elfeed-export
    :ensure nil
    :load-path "/path/to/elfeed-export")
#+end_src

* Configuration

The following table shows the customizable settings for /elfeed-export/:

#+begin_src emacs-lisp :exports results :results table :colnames '("Custom variable" "Description")
  (let ((rows))
    (mapatoms
     (lambda (symbol)
       (when (and (string-match "\\_<elfeed-export"
                                (symbol-name symbol))
                  (custom-variable-p symbol))
         (push `(,symbol
                 ,(car
                   (split-string
                    (or (get (indirect-variable symbol)
                             'variable-documentation)
                        (get symbol 'variable-documentation)
                        "")
                    "\n")))
               rows))))
    (sort rows (lambda (item1 item2)
                 (string< (car item1) (car item2)))))
#+end_src

#+RESULTS:
| Custom variable            | Description                                                          |
|----------------------------+----------------------------------------------------------------------|
| elfeed-export-exclude-tags | Do not export entries that have any of these tags.                   |
| elfeed-export-fields       | Which fields to export per entry and a function to obtain the value. |
| elfeed-export-include-tags | Export entries that have any of these tags.                          |
| elfeed-export-predicates   | Entries that match all of these predicates are exported.             |

** Customize export fields

Which fields are exported can be configured with the ~elfeed-export-fields~ variable. You may want to remove certain fields from the default, or add new fields. The variable is an alist, each element has a symbol in the car for the column name, and a function in the cdr to retrieve a value.

Some elfeed extensions supplement the elfeed index with their data, such as [[https://github.com/sp1ff/elfeed-score][elfeed-score]]. To add a field to the export which shows the score per entry, add the following in your configuration file:

#+begin_src elisp
  (add-to-list 'elfeed-export-fields
               '(score . elfeed-score-scoring-get-score-from-entry)
               t)
#+end_src

Likewise, if you use [[https://github.com/rnadler/elfeed-curate][elfeed-curate]], you can export annotations as follows:

#+begin_src elisp
  (add-to-list 'elfeed-export-fields
               '(annotation . elfeed-curate-get-entry-annotation)
               t)
#+end_src

** Customize entry filters

The variable ~elfeed-export-predicates~ is a list of predicates applied to each entry. An entry that matches all predicates makes it into the export. Each predicate takes one argument: the entry object.

*** By tag

By default, there is a tag-based predicate, which is configured by the variables ~elfeed-export-include-tags~ and ~elfeed-export-exclude-tags~. They're a list of symbols that represent a tag. E.g., to export unread items only, use:

#+begin_src elisp
  (add-to-list 'elfeed-export-include-tags 'unread)
#+end_src

By default, items tagged as =noexport= are omitted.

*** By feed

To export entries for a certain RSS feed only, use the following configuration snippet:

#+begin_src elisp
  (add-to-list 'elfeed-export-predicates
               (lambda (entry)
                 (let* ((feed (elfeed-entry-feed entry))
                        (title (elfeed-feed-title feed))
                        (_url (elfeed-feed-url feed)))
                   (string-match-p (rx "LWN.net") title))))
#+end_src

** COMMENT Attribution :noexport:

The code to generate the table of configuration items was inspired by an idea of [[https://xenodium.com/generating-elisp-org-docs/][Álvaro Ramírez]] (a.k.a. xenodium).

* Meta :noexport:

Local variables:
eval: (add-hook 'after-save-hook #'org-texinfo-export-to-info 0 t)
End: