Content server: Implement deleting of books via the web interface

src/calibre/srv/standalone.py

@@ -11,6 +11,7 @@ import sys
 from calibre import as_unicode
 from calibre.constants import is_running_from_develop, isosx, iswindows, plugins
 from calibre.db.legacy import LibraryDatabase
+from calibre.db.delete_service import shutdown as shutdown_delete_service
 from calibre.srv.bonjour import BonJour
 from calibre.srv.handler import Handler
 from calibre.srv.http_response import create_http_handler
@@ -220,4 +221,7 @@ def main(args=sys.argv):
     # Needed for dynamic cover generation, which uses Qt for drawing
     from calibre.gui2 import ensure_app, load_builtin_fonts
     ensure_app(), load_builtin_fonts()
-    server.serve_forever()
+    try:
+        server.serve_forever()
+    finally:
+        shutdown_delete_service()

src/pyj/book_list/add.pyj

@@ -82,6 +82,17 @@ def list_duplicate_book(container, container_id, job_id, data, file):
     container.appendChild(b)
 
 
+def write_access_error(msg, xhr):
+    html = msg + '<br>'
+    if xhr.status is 403:
+        un = get_interface_data().username
+        if un:
+            html += _('You are not allowed to make changes to the library') + '<hr>'
+        else:
+            html += _('You must be logged in to make changes to the library') + '<hr>'
+    return html + '<br>' + xhr.error_html
+
+
 def on_complete(container_id, job_id, end_type, xhr, ev):
     idx = state.transfers.indexOf(xhr)
     if idx > -1:
@@ -100,14 +111,8 @@ def on_complete(container_id, job_id, end_type, xhr, ev):
     elif end_type is 'abort':
         return
     else:
-        html = _('Failed to upload the file: {}').format(this.name) + '<br>'
-        if xhr.status is 403:
-            un = get_interface_data().username
-            if un:
-                html += _('You are not allowed to make changes to the library') + '<hr>'
-            else:
-                html += _('You must be logged in to make changes to the library') + '<hr>'
-        safe_set_inner_html(container, html + '<br>' + xhr.error_html)
+        html = write_access_error(_('Failed to upload the file: {}').format(this.name), xhr)
+        safe_set_inner_html(container, html)
 
 
 def fake_send(container_id, job_id):
@@ -123,7 +128,7 @@ def send_file(file, container_id, job_id, add_duplicates):
     lid = loaded_books_query().library_id
     ad = 'y' if add_duplicates else 'n'
     xhr = ajax_send_file(
-        f'/cdb/add-book/{job_id}/{ad}/{encodeURIComponent(file.name)}/{lid}',
+        f'cdb/add-book/{job_id}/{ad}/{encodeURIComponent(file.name)}/{lid}',
         file, on_complete.bind(file, container_id, job_id), on_progress.bind(None, container_id, job_id))
     state.transfers.push(xhr)
     return xhr

src/pyj/book_list/book_details.pyj

@@ -7,6 +7,7 @@ from elementmaker import E
 from gettext import gettext as _
 
 from ajax import ajax, encode_query_component
+from book_list.delete_book import start_delete_book
 from book_list.globals import get_session_data
 from book_list.item_list import create_item, create_item_list
 from book_list.library_data import (
@@ -15,7 +16,7 @@ from book_list.library_data import (
 )
 from book_list.router import back, home, open_book
 from book_list.theme import get_color, get_font_size
-from book_list.top_bar import add_button, create_top_bar, set_title, clear_buttons
+from book_list.top_bar import add_button, clear_buttons, create_top_bar, set_title
 from book_list.ui import query_as_href, set_panel_handler, show_panel
 from book_list.views import search_query_for
 from date import format_date
@@ -415,6 +416,7 @@ def render_book(container_id, book_id):
     if not c:
         return
     metadata = book_metadata(book_id)
+    render_book.title = metadata.title
     set_title(c, metadata.title)
     authors = metadata.authors.join(' & ') if metadata.authors else _('Unknown')
     alt = _('{} by {}').format(metadata.title, authors)
@@ -453,6 +455,7 @@ def add_top_bar_buttons(container_id):
     container = document.getElementById(container_id)
     if container:
         clear_buttons(container)
+        add_button(container, 'trash', action=delete_book, tooltip=_('Delete this book'))
         book_id = parse_url_params().book_id
         if book_id is '0':
             add_button(container, 'random', def(): fetch_metadata(container_id, 0);)
@@ -630,6 +633,10 @@ def search_internet(container_id):
 
     ))
 
+
+def delete_book():
+    start_delete_book(current_library_id(), render_book.book_id, render_book.title or _('Unknown'))
+
 set_panel_handler('book_details', init)
 set_panel_handler('book_details^more_actions', create_more_actions_panel)
 set_panel_handler('book_details^search_internet', search_internet)

src/pyj/book_list/delete_book.pyj

@@ -0,0 +1,110 @@
+# vim:fileencoding=utf-8
+# License: GPL v3 Copyright: 2018, Kovid Goyal <kovid at kovidgoyal.net>
+from __python__ import bound_methods, hash_literals
+
+from elementmaker import E
+from gettext import gettext as _
+
+from ajax import ajax
+from book_list.add import write_access_error
+from book_list.library_data import book_after, force_refresh_on_next_load
+from book_list.router import back
+from book_list.ui import show_panel
+from dom import clear
+from modals import create_custom_dialog
+from read_book.db import get_db
+from utils import safe_set_inner_html
+from widgets import create_button
+
+
+def delete_from_cache(library_id, book_id, title):
+    db = get_db()
+    db.delete_books_matching(library_id, book_id)
+
+
+def do_delete_from_library(parent, close_modal, library_id, book_id, title):
+    parent.appendChild(E.div(_('Deleting {0} from library, please wait...').format(title)))
+
+    def oncomplete(end_type, xhr, ev):
+        if end_type is 'load' or end_type is 'abort':
+            close_modal()
+            if end_type is 'load':
+                force_refresh_on_next_load()
+                next_book_id = book_after(book_id)
+                if next_book_id:
+                    show_panel('book_details', {'book_id': str(next_book_id), 'library_id': library_id}, True)
+                else:
+                    back()
+            return
+        clear(parent)
+        msg = E.div()
+        safe_set_inner_html(msg, write_access_error(_('Failed to delete {0}, with error:').format(title), xhr))
+        parent.appendChild(E.div(
+            msg,
+            E.div(class_='button-box',
+                create_button(_('Close'), None, close_modal, True)
+            )
+        ))
+
+    ajax(f'cdb/delete-books/{book_id}/{library_id}', oncomplete, method='POST').send()
+
+
+def confirm_delete_from_library(library_id, book_id, title):
+    create_custom_dialog(_('Are you sure?'), def(parent, close_modal):
+
+        def action(doit):
+            if doit:
+                clear(parent)
+                do_delete_from_library(parent, close_modal, library_id, book_id, title)
+            else:
+                close_modal()
+
+        msg = _('This will <b>permanently delete</b> <i>{0}</i> from your calibre library. Are you sure?').format(title)
+        m = E.div()
+        safe_set_inner_html(m, msg)
+        parent.appendChild(E.div(
+            m,
+            E.div(class_='button-box',
+                create_button(_('OK'), None, action.bind(None, True)),
+                '\xa0',
+                create_button(_('Cancel'), None, action.bind(None, False), highlight=True),
+            )
+        ))
+    )
+
+
+def choose_which_delete(library_id, book_id, title):
+
+    create_custom_dialog(_('Delete from?'), def(parent, close_modal):
+
+        def action(from_cache, from_library):
+            close_modal()
+            if from_cache:
+                delete_from_cache(library_id, book_id, title)
+            if from_library:
+                confirm_delete_from_library(library_id, book_id, title)
+
+
+        parent.appendChild(E.div(
+            E.div(_('{0} is available both in the browser cache for offline reading and in'
+                    ' your calibre library. Where do you want to delete it from?').format(title)),
+            E.div(class_='button-box',
+                create_button(_('Cache'), None, action.bind(None, True, False)),
+                '\xa0',
+                create_button(_('Library and cache'), None, action.bind(None, True, True)),
+            )
+        ))
+    )
+
+
+def delete_book_stage2(library_id, book_id, title, has_offline_copies):
+    if has_offline_copies:
+        choose_which_delete(library_id, book_id, title)
+    else:
+        confirm_delete_from_library(library_id, book_id, title)
+
+
+def start_delete_book(library_id, book_id, title):
+    book_id = int(book_id)
+    db = get_db()
+    db.has_book_matching(library_id, book_id, delete_book_stage2.bind(None, library_id, book_id, title))

src/pyj/book_list/library_data.pyj

@@ -97,6 +97,16 @@ def current_book_ids():
     return library_data.previous_book_ids.concat(library_data.search_result.book_ids)
 
 
+def book_after(book_id):
+    ids = current_book_ids()
+    idx = ids.indexOf(int(book_id))
+    if idx > -1:
+        if idx < ids.length - 1:
+            return ids[idx + 1]
+        if idx > 0:  # wrap around
+            return ids[0]
+
+
 def on_data_loaded(end_type, xhr, ev):
     load_status.current_fetch = None
     def bad_load(msg):

src/pyj/read_book/db.pyj

@@ -348,6 +348,25 @@ class DB:
             if cursor:
                 cursor.continue()
 
+    def has_book_matching(self, library_id, book_id, proceed):
+        # Should really be using a multiEntry index to avoid iterating over all
+        # books in JS, but since the number of stored books is not that large,
+        # I can't be bothered.
+        c = self.idb.transaction(['books'], 'readonly').objectStore('books').index('recent_index').openCursor(None, 'prev')
+        c.onerror = def(event):
+            proceed(False)
+        book_id = int(book_id)
+        c.onsuccess = def (ev):
+            cursor = ev.target.result
+            if cursor:
+                book = cursor.value
+                if book.key[0] is library_id and book.key[1] is book_id:
+                    proceed(True)
+                    return
+                cursor.continue()
+            else:
+                proceed(False)
+
     def delete_book(self, book, proceed):
         c = self.idb.transaction(['books', 'files'], 'readwrite')
         files = c.objectStore('files')
@@ -366,6 +385,31 @@ class DB:
                 books.delete(book.key)
         next_step()
 
+    def delete_books_matching(self, library_id, book_id, proceed):
+        c = self.idb.transaction(['books'], 'readonly').objectStore('books').index('recent_index').openCursor(None, 'prev')
+        c.onerror = def(event):
+            pass
+        book_id = int(book_id)
+        matches = v'[]'
+
+        def delete_all():
+            if matches.length:
+                book = matches.pop()
+                self.delete_book(book, delete_all)
+            else:
+                if proceed:
+                    proceed()
+
+        c.onsuccess = def (ev):
+            cursor = ev.target.result
+            if cursor:
+                book = cursor.value
+                if book.key[0] is library_id and book.key[1] is book_id:
+                    matches.push(book)
+                cursor.continue()
+            else:
+                delete_all()
+
 
 def get_db(callback, show_read_book_error):
     if not get_db.ans: