markam/linkwave.scm
Tom Willemsen 908bbc3cfb Use a transaction when adding new bookmarks
During testing it was discovered that the `first-result' procedure
throws an exception, which left the database in a somewhat
inconsistent state, the bookmark had been added, but (at least one of)
the tags weren't added.  This should make it all succeed or all fail.
2012-12-28 01:00:26 +01:00

49 lines
1.7 KiB
Scheme

(declare (uses paths))
(require-extension sqlite3)
(require-library posix srfi-4)
(: string-no-null (string -> string))
(define (string-no-null str)
(if (and (> (string-length str) 0)
(char=? (string-ref str (- (string-length str) 1)) #\nul))
(substring str 0 (- (string-length str) 1))
str))
(: print-row (string fixnum string string -> void))
(define (print-row url seconds name description)
(format #t "~a~% ~a~% ~a~% ~a~%~%" (string-no-null name) (string-no-null description)
(string-no-null url) (seconds->string seconds)))
(define (add-bookmark url name description tags)
(execute db "INSERT INTO bookmark VALUES (?, STRFTIME('%s'), ?, ?)"
url name description)
(let ((bookmark-id (last-insert-rowid db)))
(for-each (lambda (tag)
(let ((tag-id (first-result db "SELECT rowid FROM tag WHERE name = ?" tag)))
(unless tag-id
(execute db "INSERT INTO tag VALUES (?)" tag)
(set! tag-id (last-insert-rowid db)))
(execute db "INSERT INTO bookmark_tag VALUES (?, ?)"
bookmark-id tag-id)))
tags))
#t)
(define (url-string? str)
(and (> (string-length str) 7)
(or (string= (substring str 0 7) "http://")
(string= (substring str 0 8) "https://"))))
(define db (open-database (data-file "linkwave.db")))
(let ((cla (command-line-arguments)))
(if (null? cla)
(for-each-row print-row db "select * from bookmark")
(cond
((url-string? (car cla))
(with-transaction
db (lambda () (add-bookmark (car cla) (cadr cla) (caddr cla) (cdddr cla)))))
(else
(format #t "Unrecognized option: ~a~%" (car cla))))))
(finalize! db #t)