updates for threading

Dockerfile

@@ -35,8 +35,8 @@ RUN pip install --no-cache-dir --user -r /tmp/requirements.txt
 COPY --chown=user:user profiles.default.toml /home/user/.prefect/profiles.toml
 
 # Copy the application files
-COPY --chown=user:user app ./app
+COPY --chown=user:user app ./
-COPY --chown=user:user noaa_animate.py .
+# COPY --chown=user:user noaa_animate.py .
 COPY --chown=user:user start.sh .
 COPY --chown=user:user init_db.py .
 RUN chmod +x start.sh

app/app.py

@@ -1,3 +1,5 @@
+import threading
+from flows import create_animations
 import logging
 import os
 import re
@@ -68,7 +70,7 @@ def handle_api():
 
 @app.route("/videos/<path:filename>")
 def custom_static(filename):
-    return send_from_directory("../out", filename)
+    return send_from_directory("./out", filename)
 
 
 @app.route("/", methods=["GET"])
@@ -150,4 +152,5 @@ def proxy(url="", proto=PROTO):
 
 
 if __name__ == "__main__":
+    threading.Thread(target=create_animations.serve, daemon=True, kwargs={"name": "noaa-animate", "limit": 8}).start()
     app.run(host="0.0.0.0", port=9021, debug=True)

app/flows.py

@@ -0,0 +1,264 @@
+import os
+import re
+from datetime import datetime, timedelta
+from io import BytesIO
+from typing import Dict, Iterator, List
+
+import httpx
+# import imageio
+import numpy as np
+from moviepy.editor import ImageSequenceClip
+from PIL import Image
+from prefect import flow, task
+from prefect.tasks import task_input_hash
+
+BASE_URL = "https://services.swpc.noaa.gov/images/animations/geospace/"
+
+
+@task(
+    retries=3,
+    retry_delay_seconds=5,
+    cache_key_fn=task_input_hash,
+    cache_expiration=timedelta(minutes=2),
+    log_prints=True,
+)
+def get_file_links(url: str, ext: str | None = None) -> Iterator[str]:
+    response = httpx.get(url)
+    response.raise_for_status()
+    webpage_content = response.text
+    if ext is None:
+        print("Extension not supplied. Inferring (less efficient) png/jpg/jpeg")
+        exts = ["png", "jpg", "jpeg"]
+    else:
+        exts = [ext.lower()]
+    lines = webpage_content.split("\n")
+    for line in lines:
+        for ext in exts:
+            if ext in line:  # need to parse the href link
+                start_pos = line.find('href="') + len('href="')
+                end_pos = line.find('"', start_pos)
+                href = line[start_pos:end_pos]
+                if href.endswith(f"latest.{ext}"):
+                    print("Skipping latest")
+                    continue
+                if href.endswith(ext):
+                    if not href.startswith("http"):
+                        href = url + href
+                    yield href
+                break  # Exit the inner loop to avoid duplicate yields for multiple exts
+
+
+def url_tail_hash(context, parameters):
+    # return a constant
+    return parameters["url"].split("/")[-1]
+
+
+def out_path_hash(context, parameters):
+    return parameters["output_path"] + f"_L{len(parameters['images'])}"
+
+
+@task(
+    retries=5,
+    retry_delay_seconds=1,
+    cache_key_fn=task_input_hash,
+    cache_expiration=timedelta(minutes=5),
+    result_storage_key="{parameters[url]}",
+)
+def get_content(url: str, params: Dict[str, any] | None = None):
+    response = httpx.get(f"https://{url}", params=params)
+    try:
+        response.raise_for_status()
+        return response.content
+    except httpx.HTTPStatusError:
+        return None
+
+
+def preview_urls(urls):
+    print("URLS (head):")
+    print(urls[:5])
+    print("URLS (tail):")
+    print(urls[-5:])
+
+
+@task(
+    cache_key_fn=task_input_hash,
+    cache_expiration=timedelta(hours=1),
+)
+def get_images(urls: List[str] | List[str], limit: int = 0):
+    if limit > 0:
+        print(f"Limiting to {limit} urls")
+        urls = urls[-limit:]
+
+    urls = [url.replace("https://", "").replace("http://", "") for url in urls]
+    preview_urls(urls)
+
+    futures = get_content.map(urls)
+    images = [
+        (urls[i], f.result()) for i, f in enumerate(futures) if f.result() is not None
+    ]
+    return images
+
+
+def extract_timestamp_from_url(url: str) -> str:
+    # Assuming the timestamp format is in the format shown in the screenshot
+    match = re.search(r"\d{8}_\d{6}", url)
+    return match.group(0) if match else ""
+
+
+# @task(
+#     cache_key_fn=out_path_hash,
+#     cache_expiration=timedelta(minutes=3),
+#     result_storage_key="{parameters[output_path]}",
+# )
+# def create_animation(
+#     images: List[bytes], output_path: str, duration: float = 0.5
+# ) -> None:
+#     if not images:
+#         raise ValueError("No images!")
+#     pil_images = [Image.open(BytesIO(img_data)).convert("RGB") for img_data in images]
+#     imageio.mimsave(output_path, pil_images, duration=duration)
+#     return output_path
+
+
+def make_even_dimensions(image):
+    width, height = image.size
+    if width % 2 == 1:
+        width -= 1
+    if height % 2 == 1:
+        height -= 1
+    return image.resize((width, height), Image.ANTIALIAS)
+
+
+def crop_to_even(image):
+    width, height = image.size
+    # Adjust width and height to be even
+    if width % 2 == 1:
+        width -= 1
+    if height % 2 == 1:
+        height -= 1
+    return image.crop((0, 0, width, height))
+
+
+@task(
+    cache_key_fn=out_path_hash,
+    cache_expiration=timedelta(hours=4),
+    result_storage_key="{parameters[output_path]}",
+)
+def create_mp4_animation(images: List[bytes], output_path: str, fps: int = 24) -> None:
+    # Convert bytes to PIL images and then to numpy arrays
+    frames = [
+        np.array(crop_to_even(Image.open(BytesIO(img_data)).convert("RGB")))
+        for img_data in images
+    ]
+
+    # Create a video clip from the image sequence
+    clip = ImageSequenceClip(frames, fps=fps)
+
+    # Write the video clip to a file
+    clip.write_videofile(
+        output_path,
+        codec="libx264",
+        ffmpeg_params=["-pix_fmt", "yuv420p"],
+        preset="medium",
+        bitrate="800k",
+    )
+
+    return output_path
+
+
+def format_output_name(url: str, latest: bool = False):
+    if latest:
+        now = "latest"
+    else:
+        now = datetime.now().strftime("%Y%m%d-%H:%M:%S")
+    return (
+        url.replace("https://", "")
+        .replace("http://", "")
+        .replace("/", "-")
+        .replace(".", "_")
+        + now
+    )
+
+
+@task(
+    name="animate",
+    retries=0,
+    retry_delay_seconds=1,
+    log_prints=True,
+    cache_key_fn=task_input_hash,
+    cache_expiration=timedelta(minutes=3),
+)
+def animate(
+    url: str = "https://services.swpc.noaa.gov/images/animations/geospace/density/",
+    ext: str = "png",
+    latest: bool = True,
+    limit: int = 0,
+):
+    urls = get_file_links(url, ext)
+    if len(urls) == 0:
+        raise ValueError("No urls scraped")
+    images = get_images(list(sorted(urls)), limit=limit)
+    if len(images) == 0:
+        raise ValueError("No images retrieved.")
+    print(f"Retrieved {len(images)} images.")
+    sorted_images = sorted(images, key=lambda x: extract_timestamp_from_url(x[0]))
+    print("Head:")
+    print([u for u, i in sorted_images[:5]])
+    frames = [s[1] for s in sorted_images]
+    # create_animation(frames, "out.gif", duration=5)
+    out_name = format_output_name(url, latest=latest)
+    create_mp4_animation(frames, f"out/{out_name}.mp4")
+
+
+def deploy_name():
+    return datetime.utcnow().strftime("%Y-%m-%dT%H:%M:%S") + "Z"
+
+
+@flow(
+    name="create-animations",
+    retries=0,
+    retry_delay_seconds=1,
+    log_prints=True,
+    flow_run_name=None,
+    timeout_seconds=90,
+)
+def create_animations(
+    url: str | List[str] = BASE_URL + "velocity/",
+    ext: str | None = None,
+    latest: bool = False,
+    limit: int = 0,
+):
+    if isinstance(url, str):
+        url = [url]
+
+    futures = animate.map(url, ext, latest, limit)
+    return futures
+
+
+if __name__ == "__main__":
+    # make_animation.from_source(
+    #     source=TEST_REPO,
+    #     entrypoint="noaa_animate.py:make_animation",
+    # ).deploy(
+    #     name="noaa-animate", work_pool_name="process"
+    # )
+
+    from prefect.client.schemas.schedules import CronSchedule
+
+    sched = CronSchedule(cron="*/15 * * * *", timezone="America/Denver")
+
+    LINKS = [
+        BASE_URL + "density/",
+        BASE_URL + "velocity/",
+        BASE_URL + "pressure/",
+    ]
+    sched_params = {
+        "latest": True,
+        "url": LINKS,
+        "ext": "png",
+        "limit": 0,
+    }
+    create_animations.serve(
+        "noaa-animate", limit=8, schedule=None, parameters=sched_params
+    )
+    # make_animation(url)

init_db.py

@@ -16,34 +16,40 @@ def initialize_db(db_path):
         logging.info(f"{db_path} exists")  # Log a message if the database exists
         return
     try:
-        with sqlite3.connect(
+        # Using 'with' to ensure that the connection is closed automatically
-            db_path
+        with sqlite3.connect(db_path) as conn:
-        ) as conn:  # Using 'with' to ensure that the connection is closed automatically
               configure_database(conn)
     except sqlite3.Error as e:
         logging.error(f"Database error: {e}")  # Log any SQLite errors that occur
     except Exception as e:
-        logging.error(
+        logging.error(f"Exception in initialize_db: {e}")
-            f"Exception in initialize_db: {e}"
-        )  # Log any other exceptions that occur
 
 
 def configure_database(conn):
     cursor = conn.cursor()
     # Setting the journal mode to WAL for better concurrency
     cursor.execute("PRAGMA journal_mode = WAL;")
+    # Ensuring foreign key constraints are enforced for data integrity
+    cursor.execute("PRAGMA foreign_keys = ON;")
+    # disable legacy alter table behavior as it will cause problems during
+    # migrations when tables are renamed as references would otherwise be retained
+    # in some locations
+    # https://www.sqlite.org/pragma.html#pragma_legacy_alter_table
+    cursor.execute("PRAGMA legacy_alter_table=OFF")
+    # when using the WAL, we do need to sync changes on every write. sqlite
+    # recommends using 'normal' mode which is much faster
     # Setting synchronous to NORMAL for a balance between speed and reliability
     cursor.execute("PRAGMA synchronous = NORMAL;")
-    # Setting a busy timeout to prevent immediate failures when the database is locked
-    cursor.execute("PRAGMA busy_timeout = 5000;")
     # Increasing the cache size to reduce the number of disk I/O operations
-    cursor.execute("PRAGMA cache_size = -32000;")
+    cursor.execute("PRAGMA cache_size = 20000;")
     # Enabling memory-mapped I/O for potentially faster file operations
     cursor.execute("PRAGMA mmap_size = 536870912;")
+    # Setting a busy timeout to prevent immediate failures when the database is locked
+    # setting the value very high allows for more 'concurrency'
+    # without running into errors, but may result in slow api calls
+    cursor.execute("PRAGMA busy_timeout = 60000;")
     # Setting locking mode to EXCLUSIVE can enhance performance for single-user scenarios
-    cursor.execute("PRAGMA locking_mode = EXCLUSIVE;")
+    # cursor.execute("PRAGMA locking_mode = EXCLUSIVE;")
-    # Ensuring foreign key constraints are enforced for data integrity
-    cursor.execute("PRAGMA foreign_keys = ON;")
     conn.commit()  # Commit all PRAGMA configurations
 
     logging.info("Set up database with multi-user optimizations.")
@@ -55,13 +61,11 @@ def batch_transact(db_path, operations):
             db_path
         ) as conn:  # Ensure that the connection is handled properly
             cursor = conn.cursor()
-            cursor.execute(
+            # Start a transaction for batch operations
-                "BEGIN TRANSACTION;"
+            cursor.execute("BEGIN TRANSACTION;")  
-            )  # Start a transaction for batch operations
             for operation in operations:
-                cursor.execute(
+                # Execute each SQL operation provided in the operations list
-                    operation
+                cursor.execute(operation)  
-                )  # Execute each SQL operation provided in the operations list
             cursor.execute("COMMIT;")  # Commit all operations at once
     except sqlite3.Error as e:
         logging.error(f"Database error during batch transaction: {e}")
@@ -73,9 +77,8 @@ def maintenance(db_path):
     try:
         with sqlite3.connect(db_path) as conn:
             cursor = conn.cursor()
-            cursor.execute(
+            # Optimize the database to maintain performance
-                "PRAGMA optimize;"
+            cursor.execute("PRAGMA optimize;")
-            )  # Optimize the database to maintain performance
             cursor.execute("VACUUM;")  # Reclaim space and defragment the database file
     except sqlite3.Error as e:
         logging.error(f"Database error during maintenance: {e}")

start.sh

@@ -1,14 +1,14 @@
 #!/bin/bash
-# Start the web app
-cd app && make &
 
 # Start Prefect in the background
 prefect server start --host 0.0.0.0 &
 
 sleep 10
+# Start the web app
+make &
 
 # Start the deployment
-python noaa_animate.py &
+python flows.py &
 
 # Wait for all background jobs to finish
 wait