lisp/ob-sqlite.el

   1 ;;; ob-sqlite.el --- org-babel functions for sqlite database interaction
   2
   3 ;; Copyright (C) 2010-2013 Free Software Foundation, Inc.
   4
   5 ;; Author: Eric Schulte
   6 ;; Keywords: literate programming, reproducible research
   7 ;; Homepage: http://orgmode.org
   8
   9 ;; This file is part of GNU Emacs.
  10
  11 ;; GNU Emacs is free software: you can redistribute it and/or modify
  12 ;; it under the terms of the GNU General Public License as published by
  13 ;; the Free Software Foundation, either version 3 of the License, or
  14 ;; (at your option) any later version.
  15
  16 ;; GNU Emacs is distributed in the hope that it will be useful,
  17 ;; but WITHOUT ANY WARRANTY; without even the implied warranty of
  18 ;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  19 ;; GNU General Public License for more details.
  20
  21 ;; You should have received a copy of the GNU General Public License
  22 ;; along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.
  23
  24 ;;; Commentary:
  25
  26 ;; Org-Babel support for evaluating sqlite source code.
  27
  28 ;;; Code:
  29 (require 'ob)
  30 (require 'ob-eval)
  31 (require 'ob-ref)
  32
  33 (declare-function org-fill-template "org" (template alist))
  34 (declare-function org-table-convert-region "org-table"
  35                   (beg0 end0 &optional separator))
  36 (declare-function orgtbl-to-csv "org-table" (table params))
  37 (declare-function org-table-to-lisp "org-table" (&optional txt))
  38
  39 (defvar org-babel-default-header-args:sqlite '())
  40
  41 (defvar org-babel-header-args:sqlite
  42   '((db        . :any)
  43     (header    . :any)
  44     (echo      . :any)
  45     (bail      . :any)
  46     (csv       . :any)
  47     (column    . :any)
  48     (html      . :any)
  49     (line      . :any)
  50     (list      . :any)
  51     (separator . :any)
  52     (nullvalue . :any))
  53   "Sqlite specific header args.")
  54
  55 (defun org-babel-expand-body:sqlite (body params)
  56   "Expand BODY according to the values of PARAMS."
  57   (org-babel-sqlite-expand-vars
  58    body (mapcar #'cdr (org-babel-get-header params :var))))
  59
  60 (defvar org-babel-sqlite3-command "sqlite3")
  61
  62 (defun org-babel-execute:sqlite (body params)
  63   "Execute a block of Sqlite code with Babel.
  64 This function is called by `org-babel-execute-src-block'."
  65   (let ((result-params (split-string (or (cdr (assoc :results params)) "")))
  66         (db (cdr (assoc :db params)))
  67         (separator (cdr (assoc :separator params)))
  68         (nullvalue (cdr (assoc :nullvalue params)))
  69         (headers-p (equal "yes" (cdr (assoc :colnames params))))
  70         (others (delq nil (mapcar
  71                            (lambda (arg) (car (assoc arg params)))
  72                            (list :header :echo :bail :column
  73                                  :csv :html :line :list))))
  74         exit-code)
  75     (unless db (error "ob-sqlite: can't evaluate without a database"))
  76     (with-temp-buffer
  77       (insert
  78        (org-babel-eval
  79         (org-fill-template
  80          "%cmd %header %separator %nullvalue %others %csv %db "
  81          (list
  82           (cons "cmd" org-babel-sqlite3-command)
  83           (cons "header" (if headers-p "-header" "-noheader"))
  84           (cons "separator"
  85                 (if separator (format "-separator %s" separator) ""))
  86           (cons "nullvalue"
  87                 (if nullvalue (format "-nullvalue %s" nullvalue) ""))
  88           (cons "others"
  89                 (mapconcat
  90                  (lambda (arg) (format "-%s" (substring (symbol-name arg) 1)))
  91                  others " "))
  92           ;; for easy table parsing, default header type should be -csv
  93           (cons "csv" (if (or (member :csv others) (member :column others)
  94                               (member :line others) (member :list others)
  95                               (member :html others) separator)
  96                           ""
  97                         "-csv"))
  98           (cons "db " db)))
  99         ;; body of the code block
 100         (org-babel-expand-body:sqlite body params)))
 101       (if (or (member "scalar" result-params)
 102               (member "verbatim" result-params)
 103               (member "html" result-params)
 104               (member "code" result-params)
 105               (equal (point-min) (point-max)))
 106           (buffer-string)
 107         (org-table-convert-region (point-min) (point-max)
 108                                   (if (or (member :csv others)
 109                                           (member :column others)
 110                                           (member :line others)
 111                                           (member :list others)
 112                                           (member :html others) separator)
 113                                       nil
 114                                     '(4)))
 115         (org-babel-sqlite-table-or-scalar
 116          (org-babel-sqlite-offset-colnames
 117           (org-table-to-lisp) headers-p))))))
 118
 119 (defun org-babel-sqlite-expand-vars (body vars)
 120   "Expand the variables held in VARS in BODY."
 121   (mapc
 122    (lambda (pair)
 123      (setq body
 124            (replace-regexp-in-string
 125             (format "\$%s" (car pair))
 126             ((lambda (val)
 127                (if (listp val)
 128                    ((lambda (data-file)
 129                       (with-temp-file data-file
 130                         (insert (orgtbl-to-csv
 131                                  val '(:fmt (lambda (el) (if (stringp el)
 132                                                              el
 133                                                            (format "%S" el)))))))
 134                       data-file)
 135                     (org-babel-temp-file "sqlite-data-"))
 136                  (if (stringp val) val (format "%S" val))))
 137              (cdr pair))
 138             body)))
 139    vars)
 140   body)
 141
 142 (defun org-babel-sqlite-table-or-scalar (result)
 143   "If RESULT looks like a trivial table, then unwrap it."
 144   (if (and (equal 1 (length result))
 145            (equal 1 (length (car result))))
 146       (org-babel-read (caar result))
 147     (mapcar (lambda (row)
 148               (if (equal 'hline row)
 149                   'hline
 150                 (mapcar #'org-babel-read row))) result)))
 151
 152 (defun org-babel-sqlite-offset-colnames (table headers-p)
 153   "If HEADERS-P is non-nil then offset the first row as column names."
 154   (if headers-p
 155       (cons (car table) (cons 'hline (cdr table)))
 156     table))
 157
 158 (defun org-babel-prep-session:sqlite (session params)
 159   "Raise an error because support for SQLite sessions isn't implemented.
 160 Prepare SESSION according to the header arguments specified in PARAMS."
 161   (error "SQLite sessions not yet implemented"))
 162
 163 (provide 'ob-sqlite)
 164
 165
 166
 167 ;;; ob-sqlite.el ends here