More work on a server conversion interface

src/calibre/srv/convert.py

@@ -4,9 +4,42 @@
 
 from __future__ import absolute_import, division, print_function, unicode_literals
 
-from calibre.srv.errors import BookNotFound
+import os
+import shutil
+import tempfile
+from functools import partial
+from threading import Lock
+
+from calibre.srv.errors import BookNotFound, HTTPNotFound
 from calibre.srv.routes import endpoint, json
 from calibre.srv.utils import get_library_data
+from calibre.utils.monotonic import monotonic
+
+receive_data_methods = {'GET', 'POST'}
+conversion_jobs = {}
+cache_lock = Lock()
+
+
+class JobStatus(object):
+
+    def __init__(self, job_id, tdir, library_id, pathtoebook, conversion_data):
+        self.job_id = job_id
+        self.tdir = tdir
+        self.library_id, self.pathtoebook = library_id, pathtoebook
+        self.conversion_data = conversion_data
+        self.running = self.ok = True
+        self.last_check_at = monotonic()
+
+    def cleanup(self):
+        safe_delete_tree(self.tdir)
+
+
+def expire_old_jobs():
+    now = monotonic()
+    with cache_lock:
+        remove = [job_id for job_id, job_status in conversion_jobs.iteritems() if now - job_status.last_check_at >= 360]
+        for job_id in remove:
+            conversion_jobs.pop(job_id)
 
 
 def conversion_defaults():
@@ -17,6 +50,75 @@ def conversion_defaults():
     return ans
 
 
+def safe_delete_file(path):
+    try:
+        os.remove(path)
+    except EnvironmentError:
+        pass
+
+
+def safe_delete_tree(path):
+    try:
+        shutil.rmtree(path, ignore_errors=True)
+    except EnvironmentError:
+        pass
+
+
+def job_done(job):
+    with cache_lock:
+        try:
+            job_status = conversion_jobs[job.job_id]
+        except KeyError:
+            return
+        job_status.running = False
+        if job.failed:
+            job_status.ok = False
+            job_status.was_aborted = job.was_aborted
+            job_status.traceback = job.traceback
+    safe_delete_file(job_status.pathtoebook)
+
+
+def queue_job(ctx, rd, library_id, copy_format_to, fmt, book_id, conversion_data):
+    tdir = tempfile.mkdtemp(dir=rd.tdir)
+    fd, pathtoebook = tempfile.mkstemp(prefix='', suffix=('.' + fmt.lower()), dir=tdir)
+    with os.fdopen(fd, 'wb') as f:
+        copy_format_to(f)
+    job_id = ctx.start_job(
+            'Convert book %s (%s)' % (book_id, fmt), 'calibre.srv.convert_book',
+            'convert_book', args=(pathtoebook, conversion_data),
+            job_done_callback=job_done
+    )
+    expire_old_jobs()
+    with cache_lock:
+        conversion_jobs[job_id] = JobStatus(job_id, tdir, library_id, pathtoebook, conversion_data)
+    return job_id
+
+
+@endpoint('/conversion/start/{book_id}', postprocess=json, needs_db_write=True, types={'book_id': int}, methods=receive_data_methods)
+def start_conversion(ctx, rd, book_id):
+    db, library_id = get_library_data(ctx, rd)[:2]
+    if not ctx.has_id(rd, db, book_id):
+        raise BookNotFound(book_id, db)
+    data = json.loads(rd.request_body_file.read())
+    input_fmt = data['input_fmt']
+    job_id = queue_job(ctx, rd, library_id, partial(db.copy_format_to, book_id, input_fmt), input_fmt, book_id, data)
+    return job_id
+
+
+@endpoint('/conversion/status/{job_id}', postprocess=json, needs_db_write=True, types={'job_id': int})
+def conversion_status(ctx, rd, job_id):
+    with cache_lock:
+        job_status = conversion_jobs.get(job_id)
+        if job_status is None:
+            raise HTTPNotFound('No job with id: {}'.format(job_id))
+        job_status.last_check_at = monotonic()
+        if job_status.running:
+            pass
+        else:
+            del conversion_jobs[job_id]
+            job_status.cleanup()
+
+
 @endpoint('/conversion/book-data/{book_id}', postprocess=json, types={'book_id': int})
 def conversion_data(ctx, rd, book_id):
     from calibre.ebooks.conversion.config import (
@@ -40,5 +142,6 @@ def conversion_data(ctx, rd, book_id):
         'conversion_specifics': load_specifics(db, book_id),
         'title': db.field_for('title', book_id),
         'authors': db.field_for('authors', book_id),
+        'book_id': book_id
     }
     return ans

src/pyj/book_list/convert_book.pyj

@@ -5,14 +5,15 @@ from __python__ import bound_methods, hash_literals
 from elementmaker import E
 from gettext import gettext as _
 
-from ajax import ajax
+from ajax import ajax, ajax_send
 from book_list.book_details import report_load_failure
 from book_list.library_data import load_status, url_books_query
 from book_list.router import back, report_a_load_failure
 from book_list.top_bar import create_top_bar, set_title
 from book_list.ui import set_panel_handler
-from dom import add_extra_css, build_rule, clear
+from dom import add_extra_css, build_rule, clear, ensure_id
 from utils import conditional_timeout, parse_url_params
+from widgets import create_button
 
 CLASS_NAME = 'convert-book-panel'
 
@@ -24,21 +25,67 @@ add_extra_css(def():
 
 
 conversion_data = None
-conversion_data_load_status = {'loading':True, 'ok':False, 'error_html':None, 'current_fetch': None}
+conversion_data_load_status = {'loading':True, 'ok':False, 'error_html':None, 'current_fetch':None}
+
+
+def on_conversion_started(end_type, xhr, ev):
+    pass
+
+
+def get_conversion_options(container):
+    ans = {}
+    for k in Object.keys(conversion_data.conversion_defaults):
+        if Object.prototype.hasOwnProperty.call(conversion_data.conversion_specifics, k):
+            ans[k] = conversion_data.conversion_specifics[k]
+        else:
+            ans[k] = conversion_data.conversion_defaults[k]
+    return ans
+
+
+def start_conversion():
+    container = document.getElementById(conversion_data.container_id)
+    data = {
+        'input_fmt': container.querySelector('select[name="input_formats"]').value,
+        'output_fmt': container.querySelector('select[name="output_formats"]').value,
+        'options': get_conversion_options(container),
+        'book_id': conversion_data.book_id,
+    }
+    query = url_books_query()
+    ajax_send(f'/conversion/start/{conversion_data.book_id}', data, on_conversion_started, query=query)
 
 
 def create_convert_book(container):
-    conversion_data.container_id = container.id
+    conversion_data.container_id = ensure_id(container)
     set_title(container.parentNode, _('Convert: {}').format(conversion_data.title))
-    top = E.div(style="display: flex",
+    container.appendChild(E.div(class_='top'))
+
+    def generate_choice(name):
+        formats = conversion_data[name]
+        ans = E.select(name=name)
+        for fmt in formats:
+            ans.appendChild(E.option(fmt, value=fmt))
+        return ans
+    tcell = 'display: table-cell; padding-top: 1em; padding-left: 1em'
+
+    start_conv = E.div(
         E.div(
-            _('Input format')
+            E.div(
+                style='display: table-row',
+                E.div(style=tcell, _('Input format:')),
+                E.div(generate_choice('input_formats'), style=tcell),
+            ),
+            E.div(
+                style='display: table-row',
+                E.div(style=tcell, _('Output format:')),
+                E.div(generate_choice('output_formats'), style=tcell),
+            )
         ),
         E.div(
-            _('Output format')
+            style='margin: 1em',
+            create_button(_('Start conversion'), action=start_conversion)
         )
     )
-    container.appendChild(top)
+    container.lastChild.appendChild(start_conv)
 
 
 # Initialization {{{
@@ -52,7 +99,6 @@ def on_data_loaded(end_type, xhr, ev):
 
     def bad_load(msg):
         conversion_data_load_status.ok = False
-        conversion_data_load_status.loading = False
         conversion_data_load_status.error_html = msg or xhr.error_html
 
     if end_type is 'load':