library/db_layer.py

290 lines
8.3 KiB
Python

import sys
import sqlite3
import permissions
dbFile = 'sqLibrary.db'
bookTable = 'books'
bookCategoryTable='book_categories'
categoryTable = 'categories'
bookTableCreation = '''
CREATE TABLE IF NOT EXISTS books
(id INTEGER PRIMARY KEY AUTOINCREMENT,
isbn, lccn, title, subtitle, authors, edition,
publisher, publish_year, publish_month, publish_location,
pages, pagination, weight,
last_updated DATETIME DEFAULT current_timestamp,
deleted BOOLEAN DEFAULT 0);
CREATE TABLE IF NOT EXISTS categories
(cat_id INTEGER PRIMARY KEY, category STRING UNIQUE ON CONFLICT IGNORE);
CREATE TABLE IF NOT EXISTS book_categories
(id INTEGER, cat_id INTEGER);
'''
columns = ['id', 'isbn', 'lccn',
'title', 'subtitle', 'authors', 'edition',
'publisher', 'publish year', 'publish month', 'publish location',
'pages', 'pagination', 'weight', 'last updated', 'deleted']
bookTriggerCreation = '''
CREATE TRIGGER IF NOT EXISTS update_books_time AFTER UPDATE ON books
BEGIN
UPDATE books SET last_updated = DATETIME('NOW') WHERE rowid = new.rowid;
END;
CREATE TRIGGER IF NOT EXISTS delete_book AFTER DELETE ON books
BEGIN
DELETE FROM book_categories WHERE id = old.rowid;
END;
CREATE TRIGGER IF NOT EXISTS delete_category AFTER DELETE ON categories
BEGIN
DELETE FROM book_categories WHERE cat_id = old.cat_id;
END;
CREATE TRIGGER IF NOT EXISTS insert_book_category_time AFTER INSERT
ON book_categories
BEGIN
UPDATE books SET last_updated = DATETIME('NOW') WHERE id = new.id;
END;
'''
################################3
# character escaping, etc for sql queries
#################################
def _colify(s):
return s.replace(" ","_").lower()
def _stringify(v):
return '"' + str(v).strip().replace('"','""') + '"'
###################################
# book functions
##################################
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def addBook(book):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
cols = []
vals = []
for k,v in book.items():
if v!="":
cols.append(_colify(k))
vals.append(_stringify(v))
query = ("INSERT INTO "+bookTable+" ("+", ".join(cols)+") VALUES ("+
", ".join(vals)+");")
c.execute(query)
conn.commit()
c.close()
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def updateBook(book, bookID):
'''
Takes book attribute dictionary and a string representating the book ID
number, and returns updates the book accordingly
'''
conn = sqlite3.connect(dbFile)
c = conn.cursor()
updates=[]
for k,v in book.items():
updates.append(_colify(k)+"="+_stringify(v))
query = ("UPDATE "+bookTable+" SET " + ", ".join(updates)+" WHERE id = " +
str(bookID)+";")
c.execute(query)
conn.commit()
c.close()
def getBooks():
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "SELECT * FROM "+bookTable+" WHERE deleted=0;"
c.execute(query)
books = [_query_to_book(b) for b in c]
c.close()
return books
def getBooksByCategory(cat):
'''
Takes a string representating the category ID number, and returns
non-deleted books in that category
'''
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = ("SELECT "+",".join(map(_colify,columns))+" FROM "+bookTable+
" JOIN "+bookCategoryTable+
" USING (id) WHERE cat_id = :id AND deleted=0;")
c.execute(query,cat)
books = [_query_to_book(b) for b in c]
c.close()
return books
def getRemovedBooks():
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "SELECT * FROM "+bookTable+" WHERE DELETED=1;"
c.execute(query)
books = [_query_to_book(b) for b in c]
c.close()
return books
def getBookByID(bookid):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "SELECT * FROM "+bookTable+" WHERE id = "+str(bookid)+";"
c.execute(query)
book = _query_to_book(c.fetchone())
c.close()
return book
# removes book from catalogue
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def removeBook(bookid):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "UPDATE " +bookTable+ " SET deleted=1 WHERE id = "+str(bookid)+";"
c.execute(query)
conn.commit()
c.close()
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def removeBooks(books):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query1 = "UPDATE " +bookTable+ " SET deleted=1 WHERE id = :id;"
for book in books:
c.execute(query1, book)
conn.commit()
c.close()
# restores trashed books
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def restoreBooks(books):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query1 = "UPDATE " +bookTable+ " SET deleted=0 WHERE id = :id;"
for book in books:
c.execute(query1,book)
conn.commit()
c.close()
# fully deletes book from books table
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def deleteBook(bookid):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "DELETE FROM " +bookTable+ " WHERE id = "+str(bookid)+";"
c.execute(query)
conn.commit()
c.close()
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def deleteBooks(books):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "DELETE FROM " +bookTable+ " WHERE id = :id;"
for book in books:
c.execute(query, book)
conn.commit()
c.close()
def _query_to_book(book_query):
# Make a dict out of column name and query results.
# Empty entries return None, which are removed from the dict.
return dict(filter(lambda t:t[1], zip(columns,book_query)))
#########################################
# Category related functions
########################################
def getBookCategories(book):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = ("SELECT id,cat_id,category FROM "+bookCategoryTable+" JOIN "+
categoryTable+" USING (cat_id) WHERE id = :id ;")
c.execute(query,book)
cats = []
for book_id,cat_id,cat_name in c:
cats.append({'id':book_id, 'cat_id':cat_id, 'category':cat_name})
c.close()
return cats
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def categorizeBook(book, cats):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = ("INSERT OR IGNORE INTO "+bookCategoryTable+
" (id,cat_id) VALUES (?, ?);")
for cat in cats:
args = (book['id'],cat['id'])
c.execute(query,args)
conn.commit()
c.close()
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def uncategorizeBook(book, cats):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "DELETE FROM "+bookCategoryTable+" WHERE (id = ? AND cat_id = ?);"
for cat in cats:
args = (book['id'],cat['id'])
c.execute(query,args)
conn.commit()
c.close()
def getCategories():
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = "SELECT cat_id, category FROM "+categoryTable+";"
c.execute(query)
cats = []
for cat_id,cat in c:
cats.append({'id':cat_id, 'category':cat})
c.close()
return cats
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def addCategory(cat):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query = ("INSERT OR IGNORE INTO "+categoryTable+" (category) VALUES ("
+_stringify(cat)+");")
c.execute(query)
conn.commit()
c.close()
@permissions.check_permissions(permissions.PERMISSION_LIBCOM)
def deleteCategories(cats):
conn = sqlite3.connect(dbFile)
c = conn.cursor()
query1 = "DELETE FROM " +categoryTable+ " WHERE cat_id = :id;"
for cat in cats:
c.execute(query1, cat)
conn.commit()
c.close()
#########################################
# Database initialization
#########################################
def _createBooksTable():
conn = sqlite3.connect(dbFile)
c = conn.cursor()
c.executescript(bookTableCreation)
conn.commit()
c.close()
def _createTriggers():
conn = sqlite3.connect(dbFile)
c = conn.cursor()
c.executescript(bookTriggerCreation)
conn.commit()
c.close()
def initializeDatabase():
_createBooksTable()
_createTriggers()