save data to esp flash

Author: tomas-fryza

examples/31-asyncio-files/save_to_flash.py

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+import uasyncio as asyncio
+import sys
+import os
+
+# Function to generate a unique file name with a three-digit integer
+def generate_filename():
+    base_name = "output"
+    files = os.listdir()
+
+    max_num = 0
+    for file in files:
+        if file.startswith(base_name) and file.endswith('.txt'):
+            try:
+                num = int(file[len(base_name):-4])
+                max_num = max(max_num, num)  # Find the highest number
+            except ValueError:
+                continue
+
+    new_file_name = f"{base_name}_{max_num + 1:03d}.txt"
+    
+    return new_file_name
+
+# Open file for writing (for Process 2)
+try:
+    fname = generate_filename()
+    file = open(fname, 'w')
+    print(f"New file `{fname}` created")
+except OSError as e:
+    print("[!] Failed to open file:", e)
+    sys.exit()
+
+# Process 1: Print to serial monitor
+async def process_to_serial():
+    while True:
+        print("This is being printed to the serial monitor")
+        await asyncio.sleep(1)
+
+# Process 2: Write to file
+async def process_to_file():
+    while True:
+        file.write("This is being written to the file\n")
+        file.flush()  # Ensure data is written immediately
+        await asyncio.sleep(1)
+
+# Main coroutine
+async def main():
+    print("Starting tasks...")
+    task1 = asyncio.create_task(process_to_serial())
+    task2 = asyncio.create_task(process_to_file())
+
+    # Run both tasks concurrently
+    try:
+        await asyncio.gather(task1, task2)
+    except asyncio.CancelledError:
+        print("Tasks cancelled.")
+
+try:
+    # Event loop used to schedule and run tasks
+    loop = asyncio.get_event_loop()
+    loop.run_until_complete(main())
+
+except KeyboardInterrupt:
+    # This part runs when Ctrl+C is pressed
+    print("Program stopped. Exiting...")
+    
+    # Optional cleanup code
+    file.close()
+    loop.stop()  # Not available in all uasyncio versions