Support FirebaseAnalytics.GetSessionIdAsync(), and add to testapp. (#526)

* Add test to Analytics for GetSessionId.

* Add SWIG_FUTURE macro for Future<int64_t>.

* Name method GetSessionIdAsync.

* Try explicitly using long long.

* Remove explicit SWIG_FUTURE

* Revert "Remove explicit SWIG_FUTURE"

This reverts commit 808fd9b.

* Change future type to long.

* Include <cstdint> before stdint.i, and use int64_t again.

* Revert to using long long instead of int64_t.

* Remove cstdint, no longer needed.

* Revert "Remove cstdint, no longer needed."

This reverts commit 5afb56b.

* Add explanatory comment.

* Fix testapp.

* Fix delay in C# code.

* Add more debug output.

* Build error

* Remove usage of InnerException

* Move SetConsent test first.

* Fix build error.

Author: jonsimantov

analytics/src/swig/analytics.i

@@ -66,7 +66,10 @@
 %include "firebase/analytics/parameter_names.h"
 %include "firebase/analytics/user_property_names.h"
 
-
+// Including cstdint before stdint.i ensures the int64_t typedef is correct,
+// otherwise on some platforms it is defined as "long long int" instead of
+// "long int".
+#include <cstdint>
 %include "stdint.i"
 
 namespace firebase {
@@ -288,6 +291,10 @@ class ParameterCopy : private firebase::analytics::Parameter {
   }
 %}
 
+// GetSessionId returns Future<long long> in SWIG.
+%include "app/src/swig/future.i"
+%SWIG_FUTURE(Future_LongLong, long, internal, long long, FirebaseException)
+
 %include "analytics/src/include/firebase/analytics.h"
 
 %rename(ConsentType) firebase::analytics::ConsentType;

analytics/testapp/Assets/Firebase/Sample/Analytics/UIHandler.cs

@@ -151,6 +151,21 @@ public Task<string> DisplayAnalyticsInstanceId() {
       }).Unwrap();
     }
 
+    // Get the current app session ID
+    public Task<long> DisplaySessionId() {
+      return FirebaseAnalytics.GetSessionIdAsync().ContinueWithOnMainThread(task => {
+        if (task.IsCanceled) {
+          DebugLog("Session ID fetch was canceled.");
+        } else if (task.IsFaulted) {
+          DebugLog(String.Format("Encounted an error fetching session ID {0}",
+                                  task.Exception.ToString()));
+        } else if (task.IsCompleted) {
+          DebugLog(String.Format("Session ID: {0}", task.Result));
+        }
+        return task;
+      }).Unwrap();
+    }
+
     // Output text to the debug log text field, as well as the console.
     public void DebugLog(string s) {
       print(s);
@@ -207,6 +222,9 @@ void GUIDisplayControls() {
         if (GUILayout.Button("Show Analytics Instance ID")) {
           DisplayAnalyticsInstanceId();
         }
+        if (GUILayout.Button("Show Session ID")) {
+          DisplaySessionId();
+	}
         if (GUILayout.Button("Test SetConsent")) {
           AnalyticsSetConsent();
         }

analytics/testapp/Assets/Firebase/Sample/Analytics/UIHandlerAutomated.cs

@@ -30,6 +30,7 @@ public override void Start() {
         TestAnalyticsScoreDoesNotThrow,
         TestAnalyticsGroupJoinDoesNotThrow,
         TestAnalyticsLevelUpDoesNotThrow,
+        TestGetSessionId,
 	TestAnalyticsSetConsentDoesNotThrow,
         TestInstanceIdChangeAfterReset,
         TestResetAnalyticsData,
@@ -194,6 +195,27 @@ Task TestInstanceIdChangeAfterReset() {
       return tcs.Task;
     }
 
+    Task TestGetSessionId() {
+      // Depending on platform, GetSessionId needs a few seconds for Analytics
+      // to initialize (especially on iOS simulator). Pause for 5 seconds before
+      // running this test.
+      var tcs = new TaskCompletionSource<bool>();
+      Task.Delay(TimeSpan.FromSeconds(5)).ContinueWithOnMainThread(task_ => {
+	  base.DisplaySessionId().ContinueWithOnMainThread(task => {
+	      if (task.IsCanceled) {			      	 
+		tcs.TrySetException(new Exception("Unexpectedly canceled"));
+	      } else if (task.IsFaulted) {
+		tcs.TrySetException(task.Exception);
+	      } else if (task.Result == 0) {
+		tcs.TrySetException(new Exception("Zero ID returned"));
+	      } else {
+		tcs.TrySetResult(true);
+	      }
+	    });
+	});
+      return tcs.Task;
+    }
+
     Task TestResetAnalyticsData() {
       TaskCompletionSource<bool> tcs = new TaskCompletionSource<bool>();
       base.DisplayAnalyticsInstanceId().ContinueWithOnMainThread(task => {