Towards proper session handling.

app.py

@@ -33,6 +33,7 @@
 # * Vajira Thambawita <[email protected]>
 # * Thomas Dreibholz <[email protected]>
 
+import datetime
 import deepfakeecg
 import ecg_plot
 import gradio
@@ -49,10 +50,17 @@ import PIL
 
 
 TempDirectory      = None
+Sessions           = {}
 LastResults        = None
 SelectedECGIndex   = 0
 
 
+# ###### Print log message ##################################################
+def log(logstring):
+   print(('\x1b[34m' + datetime.datetime.now().strftime('%Y-%m-%dT%H:%M:%S') +
+          ': ' + logstring + '\x1b[0m'));
+
+
 # ###### Make a unique session ID ###########################################
 SessionCounterLock = threading.Lock()
 SessionCounter     = 0
@@ -69,6 +77,44 @@ def generateSessionID():
    return sessionID
 
 
+
+# ###### DeepFakeECG Plus Session (session with web browser) ################
+class Session:
+
+   # ###### Constructor #####################################################
+   def __init__(self):
+      self.Lock    = threading.Lock()
+      self.Counter = 0
+      self.Results = None
+
+   # ###### Increment counter ###############################################
+   def increment(self):
+      with self.lock:
+         self.counter += 1
+         return self.counter
+
+
+# ###### Initialize a new session ###########################################
+def initializeSession(request: gradio.Request):
+   Sessions[request.session_hash] = Session()
+   log(f'Session "{request.session_hash}" initialized')
+
+
+# ###### Clean up a session #################################################
+def cleanUpSession(request: gradio.Request):
+   if request.session_hash in Sessions:
+      del instances[request.session_hash]
+   log(f'Session "{request.session_hash}" cleaned up')
+
+
+# ###### Increment counter in session #######################################
+def incrementCounter(request: gradio.Request):
+   if request.session_hash in Sessions:
+      instance = Sessions[request.session_hash]
+      return instance.increment()
+   log(f'ERROR: Session "{request.session_hash}" is not initialized!')
+
+
 # ###### Get last results ###################################################
 def getLastResults() -> list:
    return LastResults
@@ -184,20 +230,19 @@ def dataToCSV(data, outputFileName, ecgType = deepfakeecg.DATA_ECG12) -> sys.pat
 
 
 # ###### Download CSV #######################################################
-def downloadCSV(sessionID) -> None:
-   print(f'CSV #{SelectedECGIndex}!')
-   print(f"sessionID={sessionID}")
+def downloadCSV(request: gradio.Request) -> None:
+   log(f'Session "{request.session_hash}": Download CSV file')
+
 
 # ###### Download PDF #######################################################
-def downloadPDF(sessionID) -> None:
-   print(f'PDF #{SelectedECGIndex}!')
-   print(f"sessionID={sessionID}")
+def downloadPDF(request: gradio.Request) -> None:
+   log(f'Session "{request.session_hash}": Download PDF file')
 
 
 # ###### Analyze the selected ECG ###########################################
-def analyze() -> None:
+def analyze(request: gradio.Request) -> None:
 
-   print(f'Analyze #{SelectedECGIndex}!')
+   log(f'Session "{request.session_hash}": Analyze #{SelectedECGIndex}!')
 
    data = getLastResult(SelectedECGIndex)
    print(data)
@@ -275,6 +320,12 @@ img.logo-image {
 # ====== Create GUI =========================================================
 with gradio.Blocks(css = css, theme = gradio.themes.Glass(secondary_hue=gradio.themes.colors.blue)) as gui:
 
+   # ====== Session handling ================================================
+   # Session initialization, to be called when page is loaded
+   gui.load(initializeSession)
+   # Session clean-up, to be called when page is closed/refreshed
+   gui.unload(cleanUpSession)
+
    # ====== Unique session ID for this instance =============================
    sessionID = gradio.State(0)
    gui.load(generateSessionID, outputs = [ sessionID ])
@@ -324,8 +375,8 @@ with gradio.Blocks(css = css, theme = gradio.themes.Glass(secondary_hue=gradio.t
    buttonAnalyze.click(analyze)
 
    # ====== Add click event handling for download buttons ===================
-   buttonCSV.click(downloadCSV, inputs = [ sessionID ])
-   buttonPDF.click(downloadPDF, inputs = [ sessionID ])
+   buttonCSV.click(downloadCSV)
+   buttonPDF.click(downloadPDF)
 
    # ====== Run on startup ==================================================
    gui.load(predict,
@@ -336,8 +387,12 @@ with gradio.Blocks(css = css, theme = gradio.themes.Glass(secondary_hue=gradio.t
             outputs = [ outputGallery ]
            )
 
+
 # ====== Run the GUI ========================================================
 if __name__ == "__main__":
    TempDirectory = tempfile.TemporaryDirectory('DeepFakeECGPlus')
-   gui.launch(allowed_paths = [ TempDirectory ])
+   log(f'Prepared temporary directory {TempDirectory.name}')
+   gui.launch(allowed_paths = [ TempDirectory.name ])
+   log(f'Cleaning up temporary directory {TempDirectory.name}')
    TempDirectory.cleanup()
+   log('Done!')