New PreviewManager to handle generating previews asynchronously (#86)

* Add PreviewManager

* Refactoring and better error handling

* Integrate PreviewManager into api_server.py

* Integrate PreviewManager into distributed_job_manager.py

* Add method to preview_manager.py to delete previews and integrate it into api_server

* Misc logging improvements

* Misc code cleanup

* Replace existing preview on job completion - Minor code fixes

src/api/api_server.py

@@ -19,17 +19,17 @@ import yaml
 from flask import Flask, request, send_file, after_this_request, Response, redirect, url_for, abort
 
 from src.api.add_job_helpers import handle_uploaded_project_files, process_zipped_project
+from src.api.preview_manager import PreviewManager
 from src.api.serverproxy_manager import ServerProxyManager
 from src.distributed_job_manager import DistributedJobManager
 from src.engines.core.base_worker import string_to_status, RenderStatus
 from src.engines.engine_manager import EngineManager
 from src.render_queue import RenderQueue, JobNotFoundError
+from src.utilities.benchmark import cpu_benchmark, disk_io_benchmark
 from src.utilities.config import Config
 from src.utilities.misc_helper import system_safe_path, current_system_os, current_system_cpu, \
     current_system_os_version, num_to_alphanumeric
-from src.utilities.server_helper import generate_thumbnail_for_job
 from src.utilities.zeroconf_server import ZeroconfServer
-from src.utilities.benchmark import cpu_benchmark, disk_io_benchmark
 
 logger = logging.getLogger()
 server = Flask(__name__)
@@ -85,43 +85,31 @@ def long_polling_jobs():
 
 @server.route('/api/job/<job_id>/thumbnail')
 def job_thumbnail(job_id):
+
+    try:
         big_thumb = request.args.get('size', False) == "big"
         video_ok = request.args.get('video_ok', False)
-    found_job = RenderQueue.job_with_id(job_id, none_ok=True)
+        found_job = RenderQueue.job_with_id(job_id, none_ok=False)
-    if found_job:
 
-        os.makedirs(server.config['THUMBS_FOLDER'], exist_ok=True)
+        # trigger a thumbnail update - just in case
-        thumb_video_path = os.path.join(server.config['THUMBS_FOLDER'], found_job.id + '.mp4')
+        PreviewManager.update_previews_for_job(found_job, wait_until_completion=True, timeout=60)
-        thumb_image_path = os.path.join(server.config['THUMBS_FOLDER'], found_job.id + '.jpg')
+        previews = PreviewManager.get_previews_for_job(found_job)
-        big_video_path = os.path.join(server.config['THUMBS_FOLDER'], found_job.id + '_big.mp4')
+        all_previews_list = previews.get('output', previews.get('input', []))
-        big_image_path = os.path.join(server.config['THUMBS_FOLDER'], found_job.id + '_big.jpg')
 
-        # generate regular thumb if it doesn't exist
+        video_previews = [x for x in all_previews_list if x['kind'] == 'video']
-        if not os.path.exists(thumb_video_path) and not os.path.exists(thumb_video_path + '_IN-PROGRESS') and \
+        image_previews = [x for x in all_previews_list if x['kind'] == 'image']
-                found_job.status not in [RenderStatus.CANCELLED, RenderStatus.ERROR]:
+        filtered_list = video_previews if video_previews and video_ok else image_previews
-            generate_thumbnail_for_job(found_job, thumb_video_path, thumb_image_path, max_width=240)
 
-        # generate big thumb if it doesn't exist
+        # todo - sort by size or other metrics here
-        if not os.path.exists(big_video_path) and not os.path.exists(big_image_path + '_IN-PROGRESS') and \
+        if filtered_list:
-                found_job.status not in [RenderStatus.CANCELLED, RenderStatus.ERROR]:
+            preview_to_send = filtered_list[0]
-            generate_thumbnail_for_job(found_job, big_video_path, big_image_path, max_width=800)
+            mime_types = {'image': 'image/jpeg', 'video': 'video/mp4'}
-
+            file_mime_type = mime_types.get(preview_to_send['kind'], 'unknown')
-        # generated videos
+            return send_file(preview_to_send['filename'], mimetype=file_mime_type)
-        if video_ok:
+    except Exception as e:
-            if big_thumb and os.path.exists(big_video_path) and not os.path.exists(
+        logger.exception(f'Error getting thumbnail: {e}')
-                    big_video_path + '_IN-PROGRESS'):
+        return f'Error getting thumbnail: {e}', 500
-                return send_file(big_video_path, mimetype="video/mp4")
+    return "No thumbnail available", 404
-            elif os.path.exists(thumb_video_path) and not os.path.exists(thumb_video_path + '_IN-PROGRESS'):
-                return send_file(thumb_video_path, mimetype="video/mp4")
-
-        # Generated thumbs
-        if big_thumb and os.path.exists(big_image_path):
-            return send_file(big_image_path, mimetype='image/jpeg')
-        elif os.path.exists(thumb_image_path):
-            return send_file(thumb_image_path, mimetype='image/jpeg')
-
-        return found_job.status.value, 200
-    return found_job.status.value, 404
 
 
 # Get job file routing
@@ -305,14 +293,7 @@ def delete_job(job_id):
         if server.config['UPLOAD_FOLDER'] in output_dir and os.path.exists(output_dir):
             shutil.rmtree(output_dir)
 
-        # Remove any thumbnails
+        PreviewManager.delete_previews_for_job(found_job)
-        for filename in os.listdir(server.config['THUMBS_FOLDER']):
-            if job_id in filename:
-                os.remove(os.path.join(server.config['THUMBS_FOLDER'], filename))
-
-        thumb_path = os.path.join(server.config['THUMBS_FOLDER'], found_job.id + '.mp4')
-        if os.path.exists(thumb_path):
-            os.remove(thumb_path)
 
         # See if we own the project_dir (i.e. was it uploaded)
         project_dir = os.path.dirname(os.path.dirname(found_job.input_path))
@@ -495,6 +476,7 @@ def start_server():
             RenderQueue.evaluate_queue()
             time.sleep(delay_sec)
 
+    try:
         # get hostname
         local_hostname = socket.gethostname()
         local_hostname = local_hostname + (".local" if not local_hostname.endswith(".local") else "")
@@ -503,18 +485,20 @@ def start_server():
         server.config['HOSTNAME'] = local_hostname
         server.config['PORT'] = int(Config.port_number)
         server.config['UPLOAD_FOLDER'] = system_safe_path(os.path.expanduser(Config.upload_folder))
-    server.config['THUMBS_FOLDER'] = system_safe_path(os.path.join(os.path.expanduser(Config.upload_folder), 'thumbs'))
         server.config['MAX_CONTENT_PATH'] = Config.max_content_path
         server.config['enable_split_jobs'] = Config.enable_split_jobs
 
-    # Setup directory for saving engines to
+        # Setup storage directories
         EngineManager.engines_path = system_safe_path(os.path.join(os.path.join(os.path.expanduser(Config.upload_folder),
                                                                                 'engines')))
         os.makedirs(EngineManager.engines_path, exist_ok=True)
+        PreviewManager.storage_path = system_safe_path(os.path.join(os.path.expanduser(Config.upload_folder), 'previews'))
+
+        server.config['THUMBS_FOLDER'] = PreviewManager.storage_path  # todo: remove this
 
         # Debug info
         logger.debug(f"Upload directory: {server.config['UPLOAD_FOLDER']}")
-    logger.debug(f"Thumbs directory: {server.config['THUMBS_FOLDER']}")
+        logger.debug(f"Thumbs directory: {PreviewManager.storage_path}")
         logger.debug(f"Engines directory: {EngineManager.engines_path}")
 
         # disable most Flask logging
@@ -545,4 +529,6 @@ def start_server():
                        use_reloader=False, threaded=True)
         finally:
             RenderQueue.save_state()
+
+    finally:
         ZeroconfServer.stop()

src/api/preview_manager.py

@@ -0,0 +1,109 @@
+import logging
+import os
+import subprocess
+import threading
+from pathlib import Path
+
+from src.utilities.ffmpeg_helper import generate_thumbnail, save_first_frame
+
+logger = logging.getLogger()
+supported_video_formats = ['.mp4', '.mov', '.avi', '.mpg', '.mpeg', '.mxf', '.m4v', 'mkv']
+supported_image_formats = ['.jpg', '.png', '.exr', '.tif']
+
+
+class PreviewManager:
+
+    storage_path = None
+    _running_jobs = {}
+
+    @classmethod
+    def __generate_job_preview_worker(cls, job, replace_existing=False, max_width=320):
+
+        # Determine best source file to use for thumbs
+        job_file_list = job.file_list()
+        source_files = job_file_list if job_file_list else [job.input_path]
+        preview_label = "output" if job_file_list else "input"
+
+        # filter by type
+        found_image_files = [f for f in source_files if os.path.splitext(f)[-1].lower() in supported_image_formats]
+        found_video_files = [f for f in source_files if os.path.splitext(f)[-1].lower() in supported_video_formats]
+
+        # check if we even have any valid files to work from
+        if source_files and not found_video_files and not found_image_files:
+            logger.warning(f"No valid image or video files found in files from job: {job}")
+            return
+
+        base_path = os.path.join(cls.storage_path, f"{job.id}-{preview_label}-{max_width}")
+        preview_video_path = base_path + '.mp4'
+        preview_image_path = base_path + '.jpg'
+
+        if replace_existing:
+            for x in [preview_image_path, preview_video_path]:
+                try:
+                    os.remove(x)
+                except OSError:
+                    pass
+
+        # Generate image previews
+        if (found_video_files or found_image_files) and not os.path.exists(preview_image_path):
+            try:
+                path_of_source = found_image_files[-1] if found_image_files else found_video_files[-1]
+                logger.debug(f"Generating image preview for {path_of_source}")
+                save_first_frame(source_path=path_of_source, dest_path=preview_image_path, max_width=max_width)
+                logger.debug(f"Successfully created image preview for {path_of_source}")
+            except Exception as e:
+                logger.error(f"Error generating image preview for {job}: {e}")
+
+        # Generate video previews
+        if found_video_files and not os.path.exists(preview_video_path):
+            try:
+                path_of_source = found_video_files[0]
+                logger.debug(f"Generating video preview for {path_of_source}")
+                generate_thumbnail(source_path=path_of_source, dest_path=preview_video_path, max_width=max_width)
+                logger.debug(f"Successfully created video preview for {path_of_source}")
+            except subprocess.CalledProcessError as e:
+                logger.error(f"Error generating video preview for {job}: {e}")
+
+    @classmethod
+    def update_previews_for_job(cls, job, replace_existing=False, wait_until_completion=False, timeout=None):
+        job_thread = cls._running_jobs.get(job.id)
+        if job_thread and job_thread.is_alive():
+            logger.debug(f'Preview generation job already running for {job}')
+        else:
+            job_thread = threading.Thread(target=cls.__generate_job_preview_worker, args=(job, replace_existing,))
+            job_thread.start()
+            cls._running_jobs[job.id] = job_thread
+
+        if wait_until_completion:
+            job_thread.join(timeout=timeout)
+
+    @classmethod
+    def get_previews_for_job(cls, job):
+
+        directory_path = Path(cls.storage_path)
+        preview_files_for_job = [f for f in directory_path.iterdir() if f.is_file() and f.name.startswith(job.id)]
+
+        results = {}
+        for preview_filename in preview_files_for_job:
+            try:
+                pixel_width = str(preview_filename).split('-')[-1]
+                preview_label = str(os.path.basename(preview_filename)).split('-')[1]
+                extension = os.path.splitext(preview_filename)[-1].lower()
+                kind = 'video' if extension in supported_video_formats else \
+                    'image' if extension in supported_image_formats else 'unknown'
+                results[preview_label] = results.get(preview_label, [])
+                results[preview_label].append({'filename': str(preview_filename), 'width': pixel_width, 'kind': kind})
+            except IndexError:  # ignore invalid filenames
+                pass
+        return results
+
+    @classmethod
+    def delete_previews_for_job(cls, job):
+        all_previews = cls.get_previews_for_job(job)
+        flattened_list = [item for sublist in all_previews.values() for item in sublist]
+        for preview in flattened_list:
+            try:
+                logger.debug(f"Removing preview: {preview['filename']}")
+                os.remove(preview['filename'])
+            except OSError as e:
+                logger.error(f"Error removing preview '{preview.get('filename')}': {e}")

src/distributed_job_manager.py

@@ -10,6 +10,7 @@ import requests
 from plyer import notification
 from pubsub import pub
 
+from src.api.preview_manager import PreviewManager
 from src.api.server_proxy import RenderServerProxy
 from src.engines.engine_manager import EngineManager
 from src.render_queue import RenderQueue
@@ -52,12 +53,18 @@ class DistributedJobManager:
             return
 
         logger.debug(f"Job {job_id} status change: {old_status} -> {new_status}")
+
+        # Update previews - Force replace if job has completed successfully
+        PreviewManager.update_previews_for_job(render_job,
+                                               replace_existing=(render_job.status == RenderStatus.COMPLETED))
+
+        # Notify parent if necessary
         if render_job.parent:  # If local job is a subjob from a remote server
             parent_id, hostname = render_job.parent.split('@')[0], render_job.parent.split('@')[-1]
             RenderServerProxy(hostname).notify_parent_of_status_change(parent_id=parent_id, subjob=render_job)
 
-        # handle cancelling all the children
+        # Cancelling children if necessary
-        elif render_job.children and new_status in [RenderStatus.CANCELLED, RenderStatus.ERROR]:
+        if render_job.children and new_status in [RenderStatus.CANCELLED, RenderStatus.ERROR]:
             for child in render_job.children:
                 child_id, hostname = child.split('@')
                 RenderServerProxy(hostname).cancel_job(child_id, confirm=True)
@@ -143,6 +150,7 @@ class DistributedJobManager:
             logger.debug("Not splitting into subjobs")
 
         RenderQueue.add_to_render_queue(worker, force_start=job_data.get('force_start', False))
+        PreviewManager.update_previews_for_job(worker)
 
         return worker
 

src/engines/core/base_worker.py

@@ -99,6 +99,9 @@ class BaseRenderWorker(Base):
         self.__process = None
         self.last_output = None
 
+    def __repr__(self):
+        return f"<{self.__class__.__name__}|{self.id}|{self.name}|{self.status}|{self.input_path}>"
+
     @property
     def total_frames(self):
         return (self.end_frame or self.project_length) - self.start_frame + 1
@@ -131,9 +134,8 @@ class BaseRenderWorker(Base):
         generated_args = [str(x) for x in self.generate_worker_subprocess()]
         generated_args_flags = [x for x in generated_args if x.startswith('-')]
         if len(generated_args_flags) != len(set(generated_args_flags)):
-            msg = "Cannot generate subprocess - Multiple arg conflicts detected"
+            msg = f"Cannot generate subprocess - Multiple arg conflicts detected: {generated_args}"
             logger.error(msg)
-            logger.debug(f"Generated args for subprocess: {generated_args}")
             raise ValueError(msg)
         return generated_args
 

src/render_queue.py

@@ -121,19 +121,19 @@ class RenderQueue:
 
     @classmethod
     def start_job(cls, job):
-        logger.info(f'Starting render: {job.name} - Priority {job.priority}')
+        logger.info(f'Starting job: {job} - Priority {job.priority}')
         job.start()
         cls.save_state()
 
     @classmethod
     def cancel_job(cls, job):
-        logger.info(f'Cancelling job ID: {job.id}')
+        logger.info(f'Cancelling job: {job}')
         job.stop()
         return job.status == RenderStatus.CANCELLED
 
     @classmethod
     def delete_job(cls, job):
-        logger.info(f"Deleting job ID: {job.id}")
+        logger.info(f"Deleting job: {job}")
         job.stop()
         cls.job_queue.remove(job)
         cls.session.delete(job)