Fixed review comments.

1. Changed Ad redirect urls to products.
2. Removed leftovers from Dockerfile/kub*manifests*yaml
3. Added retry for StackDriver.
4. Added log for Ad request.
5. Added comment for gradle caching.
6. Added README.md to src/adservice.

kubernetes-manifests/adservice.yaml

@@ -31,10 +31,6 @@ spec:
         env:
         - name: PORT
           value: "9555"
-        - name: LISTEN_ADDR
-          value: "0.0.0.0"
-        - name: ADS_URL
-          value: "http://localhost:10010/ads/"
         resources:
           requests:
             cpu: 200m

src/adservice/Dockerfile

@@ -2,6 +2,9 @@
 FROM openjdk:8
 RUN apt-get update && apt-get install net-tools telnet
 WORKDIR /app
+
+# Next three steps are for caching dependency downloads
+# to improve subsequent docker build.
 COPY ["build.gradle", "gradlew", "./"]
 COPY gradle gradle
 RUN ./gradlew downloadRepos
@@ -10,4 +13,3 @@ COPY . .
 RUN ./gradlew installDist
 EXPOSE 9555
 ENTRYPOINT ["/app/build/install/hipstershop/bin/AdService"]
-#ENTRYPOINT ["tail", "-f", "/dev/null"]

src/adservice/README.md

@@ -0,0 +1,26 @@
+# Ad Service
+
+The Ad service provides advertisement based on context keys. If no context keys are provided then it returns random ads.
+
+## Local Build
+
+The Ad service uses gradlew to compile/install/distribute. Gradle wrapper is already part of the source code. To build Ad Service, run
+```
+    cd src/adservice; ./gradlew installDist
+```
+It will create executable script src/adservice/build/install/hipstershop/bin/AdService
+
+### Upgrade gradle version
+If you need to upgrade the version of gradle then run
+```
+    cd src/adservice ; ./gradlew wrapper --gradle-version <new-version>
+```
+
+## Docker Build
+
+From repository root, run:
+
+```
+docker build --file src/adservice/Dockerfile .
+```
+

src/adservice/src/main/java/hipstershop/AdService.java

@@ -44,6 +44,7 @@ import java.util.ArrayList;
 import java.util.HashMap;
 import java.util.List;
 import java.util.Random;
+import java.util.concurrent.TimeUnit;
 import java.util.logging.Level;
 import java.util.logging.Logger;
 
@@ -101,6 +102,7 @@ public class AdService {
         Span span = tracer.getCurrentSpan();
         span.putAttribute("method", AttributeValue.stringAttributeValue("getAds"));
         List<Ad> ads = new ArrayList<>();
+        logger.info("received ad request (context_words=" + req.getContextKeysCount() + ")");
         if (req.getContextKeysCount() > 0) {
           span.addAnnotation(
               "Constructing Ads using context",
@@ -162,13 +164,12 @@ public class AdService {
   }
 
   static void initializeAds() {
-    String adsUrl = System.getenv("ADS_URL");
+    cacheMap.put("camera", Ad.newBuilder().setRedirectUrl( "/product/2ZYFJ3GM2N")
-    cacheMap.put("camera", Ad.newBuilder().setRedirectUrl(adsUrl + "/camera")
+        .setText("Film camera for sale. 50% off.").build());
-        .setText("MyPro camera for sale. 50% off.").build());
+    cacheMap.put("bike", Ad.newBuilder().setRedirectUrl("/product/9SIQT8TOJO")
-    cacheMap.put("bike", Ad.newBuilder().setRedirectUrl(adsUrl + "/bike")
+        .setText("City Bike for sale. 10% off.").build());
-        .setText("ZoomZoom bike for sale. 10% off.").build());
+    cacheMap.put("kitchen", Ad.newBuilder().setRedirectUrl("/product/1YMWWN1N4O")
-    cacheMap.put("kitchen", Ad.newBuilder().setRedirectUrl(adsUrl + "/kitchen")
+        .setText("Home Barista kitchen kit for sale. Buy one, get second kit for free").build());
-        .setText("CutPro knife for sale. Buy one, get second set for free").build());
     logger.info("Default Ads initialized");
   }
 
@@ -183,7 +184,10 @@ public class AdService {
 
     // Registers logging trace exporter.
     LoggingTraceExporter.register();
+    long sleepTime = 10; /* seconds */
+    int maxAttempts = 3;
 
+    for (int i=0; i<maxAttempts; i++) {
       try {
         StackdriverTraceExporter.createAndRegister(
             StackdriverTraceConfiguration.builder().build());
@@ -192,8 +196,19 @@ public class AdService {
                 .setExportInterval(Duration.create(15, 0))
                 .build());
       } catch (Exception e) {
+        if (i==(maxAttempts-1)) {
           logger.log(Level.WARNING, "Failed to register Stackdriver Exporter." +
-          " Census tracing and stats data will not reported to Stackdriver. Error message: " + e.toString());
+              " Tracing and Stats data will not reported to Stackdriver. Error message: " + e
+              .toString());
+        } else {
+          logger.info("Attempt to register Stackdriver Exporter in " + sleepTime + " seconds ");
+          try {
+            Thread.sleep(TimeUnit.SECONDS.toMillis(sleepTime));
+          } catch (Exception se) {
+            logger.log(Level.WARNING, "Exception while sleeping" + se.toString());
+          }
+        }
+      }
     }
 
     // Register Prometheus exporters and export metrics to a Prometheus HTTPServer.

src/adservice/src/main/java/hipstershop/AdServiceClient.java

@@ -142,6 +142,10 @@ public class AdServiceClient {
 
     // Registers Stackdriver exporters.
     if (cloudProjectId != null) {
+      long sleepTime = 10; /* seconds */
+      int maxAttempts = 3;
+
+      for (int i=0; i<maxAttempts; i++) {
         try {
           StackdriverTraceExporter.createAndRegister(
               StackdriverTraceConfiguration.builder().setProjectId(cloudProjectId).build());
@@ -151,8 +155,19 @@ public class AdServiceClient {
                   .setExportInterval(Duration.create(15, 0))
                   .build());
         } catch (Exception e) {
+          if (i==(maxAttempts-1)) {
             logger.log(Level.WARNING, "Failed to register Stackdriver Exporter." +
-            " Census tracing and stats data will not reported to Stackdriver. Error message: " + e.toString());
+                " Tracing and Stats data will not reported to Stackdriver. Error message: " + e
+                .toString());
+          } else {
+            logger.info("Attempt to register Stackdriver Exporter in " + sleepTime + " seconds");
+            try {
+              Thread.sleep(TimeUnit.SECONDS.toMillis(sleepTime));
+            } catch (Exception se) {
+              logger.log(Level.WARNING, "Exception while sleeping" + e.toString());
+            }
+          }
+        }
       }
     }