Merge pull request #15 from target/scale_log_addition

Adding lock and log for scale stable weight

Author: arpal7

src/main/java/com/target/devicemanager/components/scale/ScaleController.java

@@ -86,15 +86,16 @@ public SseEmitter getLiveWeight() throws IOException {
                     content = @Content(schema = @Schema(implementation = DeviceError.class)))
     })
     public FormattedWeight getStableWeight() throws ScaleException {
+        long randomWithTS = System.currentTimeMillis();
         String url = "/v1/scale/stableweight";
-        LOGGER.info("request: " + url);
+        LOGGER.info("request: " + randomWithTS + " " + url);
         CompletableFuture<FormattedWeight> completableFuture = new CompletableFuture<>();
         try {
             FormattedWeight weight = scaleManager.getStableWeight(completableFuture);
-            LOGGER.info("response: " + url + " - 200 OK");
+            LOGGER.info("response: " + randomWithTS + " " + url + " - 200 OK ");
             return weight;
         } catch (ScaleException scaleException) {
-            LOGGER.info("response: " + url + " - " + scaleException.getDeviceError().getStatusCode().toString() + ", " + scaleException.getDeviceError());
+            LOGGER.info("response: " + randomWithTS + " " + url + " - " + scaleException.getDeviceError().getStatusCode().toString() + ", " + scaleException.getDeviceError());
             throw scaleException;
         }
     }

src/main/java/com/target/devicemanager/components/scale/ScaleDevice.java

@@ -193,15 +193,19 @@ void startStableWeightRead(int timeout) {
             long currentTimeMsec = System.currentTimeMillis();
             long endTimeMsec = currentTimeMsec + timeout;
             while(currentTimeMsec <= endTimeMsec) {
+                LOGGER.error("Read Weight Time Remaining " + (endTimeMsec - currentTimeMsec));
                 try {
                     scale.readWeight(weight, STABLE_WEIGHT_READ_TIMEOUT);
+                    LOGGER.error("After ReadWeight " + weight[0]);
                     fireScaleStableWeightDataEvent(new FormattedWeight(weight[0]));
                     stableWeightInProgress = false;
                     weight = new int[1];
                     return;
                 } catch (JposException jposException) {
                     if(isConnected()) {
                         LOGGER.error(MARKER, "Scale Failed to Read Stable Weight: " + jposException.getErrorCode() + ", " + jposException.getErrorCodeExtended());
+                    } else {
+                        LOGGER.error(MARKER, "Scale not connected in Read Stable Weight: " + jposException.getErrorCode() + ", " + jposException.getErrorCodeExtended());
                     }
                     if(jposException.getErrorCode() != JposConst.JPOS_E_TIMEOUT) {
                         fireScaleWeightErrorEvent(jposException);

src/main/java/com/target/devicemanager/components/scale/ScaleManager.java

@@ -113,22 +113,27 @@ void subscribeToLiveWeight(SseEmitter liveWeightEmitter) throws IOException {
     }
 
     public FormattedWeight getStableWeight(CompletableFuture<FormattedWeight> stableWeightClient) throws ScaleException {
-        //Create new future and add it to the list
-        stableWeightClients.add(stableWeightClient);
-        scaleDevice.startStableWeightRead(STABLE_WEIGHT_TIMEOUT_MSEC);
-        try {
-            //Timeout as a double check against timing errors that would cause us to hang forever
-            return stableWeightClient.get(HANG_TIMEOUT_MSEC, TimeUnit.MILLISECONDS);
-        } catch (ExecutionException executionException) {
-            Throwable jposException = executionException.getCause();
-            ScaleException scaleException = new ScaleException((JposException)jposException);
-            throw scaleException;
-        } catch (InterruptedException interruptedException) {
-            ScaleException scaleException = new ScaleException(new JposException(JposConst.JPOS_E_FAILURE));
-            throw scaleException;
-        } catch (TimeoutException timeoutException) {
-            ScaleException scaleException = new ScaleException(new JposException(JposConst.JPOS_E_TIMEOUT));
-            throw scaleException;
+        if (scaleDevice.tryLock()) {
+            //Create new future and add it to the list
+            stableWeightClients.add(stableWeightClient);
+            scaleDevice.startStableWeightRead(STABLE_WEIGHT_TIMEOUT_MSEC);
+            try {
+                //Timeout as a double check against timing errors that would cause us to hang forever
+                return stableWeightClient.get(HANG_TIMEOUT_MSEC, TimeUnit.MILLISECONDS);
+            } catch (ExecutionException executionException) {
+                Throwable jposException = executionException.getCause();
+                throw (new ScaleException((JposException)jposException));
+            } catch (InterruptedException interruptedException) {
+                throw (new ScaleException(new JposException(JposConst.JPOS_E_FAILURE)));
+            } catch (TimeoutException timeoutException) {
+                throw (new ScaleException(new JposException(JposConst.JPOS_E_TIMEOUT)));
+            }
+            finally {
+                scaleDevice.unlock();
+            }
+        } else {
+            LOGGER.error("Scale Device Busy. Please Wait To Get Stable Weight.");
+            throw (new ScaleException(new JposException(JposConst.JPOS_E_BUSY)));
         }
     }