lisp/ob-sqlite.el

   1 ;;; ob-sqlite.el --- org-babel functions for sqlite database interaction
   2
   3 ;; Copyright (C) 2010-2012  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
  38 (defvar org-babel-default-header-args:sqlite '())
  39
  40 (defvar org-babel-header-args:sqlite
  41   '((db        . :any)
  42     (header    . :any)
  43     (echo      . :any)
  44     (bail      . :any)
  45     (csv       . :any)
  46     (column    . :any)
  47     (html      . :any)
  48     (line      . :any)
  49     (list      . :any)
  50     (separator . :any)
  51     (nullvalue . :any))
  52   "Sqlite specific header args.")
  53
  54 (defun org-babel-expand-body:sqlite (body params)
  55   "Expand BODY according to the values of PARAMS."
  56   (org-babel-sqlite-expand-vars
  57    body (mapcar #'cdr (org-babel-get-header params :var))))
  58
  59 (defvar org-babel-sqlite3-command "sqlite3")
  60
  61 (defun org-babel-execute:sqlite (body params)
  62   "Execute a block of Sqlite code with Babel.
  63 This function is called by `org-babel-execute-src-block'."
  64   (let ((result-params (split-string (or (cdr (assoc :results params)) "")))
  65         (db (cdr (assoc :db params)))
  66         (separator (cdr (assoc :separator params)))
  67         (nullvalue (cdr (assoc :nullvalue params)))
  68         (headers-p (equal "yes" (cdr (assoc :colnames params))))
  69         (others (delq nil (mapcar
  70                            (lambda (arg) (car (assoc arg params)))
  71                            (list :header :echo :bail :column
  72                                  :csv :html :line :list))))
  73         exit-code)
  74     (unless db (error "ob-sqlite: can't evaluate without a database."))
  75     (with-temp-buffer
  76       (insert
  77        (org-babel-eval
  78         (org-fill-template
  79          "%cmd %header %separator %nullvalue %others %csv %db "
  80          (list
  81           (cons "cmd" org-babel-sqlite3-command)
  82           (cons "header" (if headers-p "-header" "-noheader"))
  83           (cons "separator"
  84                 (if separator (format "-separator %s" separator) ""))
  85           (cons "nullvalue"
  86                 (if nullvalue (format "-nullvalue %s" nullvalue) ""))
  87           (cons "others"
  88                 (mapconcat
  89                  (lambda (arg) (format "-%s" (substring (symbol-name arg) 1)))
  90                  others " "))
  91           ;; for easy table parsing, default header type should be -csv
  92           (cons "csv" (if (or (member :csv others) (member :column others)
  93                               (member :line others) (member :list others)
  94                               (member :html others) separator)
  95                           ""
  96                         "-csv"))
  97           (cons "db " db)))
  98         ;; body of the code block
  99         (org-babel-expand-body:sqlite body params)))
 100       (if (or (member "scalar" result-params)
 101               (member "verbatim" result-params)
 102               (member "html" result-params)
 103               (member "code" result-params)
 104               (equal (point-min) (point-max)))
 105           (buffer-string)
 106         (org-table-convert-region (point-min) (point-max)
 107                                   (if (or (member :csv others)
 108                                           (member :column others)
 109                                           (member :line others)
 110                                           (member :list others)
 111                                           (member :html others) separator)
 112                                       nil
 113                                     '(4)))
 114         (org-babel-sqlite-table-or-scalar
 115          (org-babel-sqlite-offset-colnames
 116           (org-table-to-lisp) headers-p))))))
 117
 118 (defun org-babel-sqlite-expand-vars (body vars)
 119   "Expand the variables held in VARS in BODY."
 120   (mapc
 121    (lambda (pair)
 122      (setq body
 123            (replace-regexp-in-string
 124             (format "\$%s" (car pair))
 125             ((lambda (val)
 126                (if (listp val)
 127                    ((lambda (data-file)
 128                       (with-temp-file data-file
 129                         (insert (orgtbl-to-csv
 130                                  val '(:fmt (lambda (el) (if (stringp el)
 131                                                         el
 132                                                       (format "%S" el)))))))
 133                       data-file)
 134                     (org-babel-temp-file "sqlite-data-"))
 135                  (if (stringp val) val (format "%S" val))))
 136              (cdr pair))
 137             body)))
 138    vars)
 139   body)
 140
 141 (defun org-babel-sqlite-table-or-scalar (result)
 142   "If RESULT looks like a trivial table, then unwrap it."
 143   (if (and (equal 1 (length result))
 144            (equal 1 (length (car result))))
 145       (org-babel-read (caar result))
 146     (mapcar (lambda (row)
 147               (if (equal 'hline row)
 148                   'hline
 149                 (mapcar #'org-babel-read row))) result)))
 150
 151 (defun org-babel-sqlite-offset-colnames (table headers-p)
 152   "If HEADERS-P is non-nil then offset the first row as column names."
 153   (if headers-p
 154       (cons (car table) (cons 'hline (cdr table)))
 155     table))
 156
 157 (defun org-babel-prep-session:sqlite (session params)
 158   "Raise an error because support for sqlite sessions isn't implemented.
 159 Prepare SESSION according to the header arguments specified in PARAMS."
 160   (error "sqlite sessions not yet implemented"))
 161
 162 (provide 'ob-sqlite)
 163
 164
 165
 166 ;;; ob-sqlite.el ends here