Probe upstream Zen server when initializing upstream cache.

3 files changed, 28 insertions, 2 deletions

diff --git a/zenserver/upstream/upstreamcache.cpp b/zenserver/upstream/upstreamcache.cpp
index c015ef3e9..e235db516 100644
--- a/zenserver/upstream/upstreamcache.cpp
+++ b/zenserver/upstream/upstreamcache.cpp
@@ -292,8 +292,20 @@ namespace detail {
 
 		virtual bool Initialize() override
 		{
-			// TODO: Test and authenticate Zen client connection
-			return !m_Client->ServiceUrl().empty();
+			try
+			{
+				ZenStructuredCacheSession Session(*m_Client);
+				ZenCacheResult			  Result;
+				for (int32_t Attempt = 0, MaxAttempts = 3; Attempt < MaxAttempts && !Result.Success; ++Attempt)
+				{
+					Result = Session.SayHello();
+				}
+				return Result.Success;
+			}
+			catch (std::exception&)
+			{
+				return false;
+			}
 		}
 
 		virtual std::string_view DisplayName() const override { return m_DisplayName; }
diff --git a/zenserver/upstream/zen.cpp b/zenserver/upstream/zen.cpp
index 55ddd310f..be4daa30a 100644
--- a/zenserver/upstream/zen.cpp
+++ b/zenserver/upstream/zen.cpp
@@ -382,6 +382,19 @@ ZenStructuredCacheSession::~ZenStructuredCacheSession()
 }
 
 ZenCacheResult
+ZenStructuredCacheSession::SayHello()
+{
+	ExtendableStringBuilder<256> Uri;
+	Uri << m_Client.ServiceUrl() << "/test/hello";
+
+	cpr::Session& Session = m_SessionState->Session;
+	Session.SetOption(cpr::Url{Uri.c_str()});
+	cpr::Response Response = Session.Get();
+
+	return {.Bytes = Response.downloaded_bytes, .ElapsedSeconds = Response.elapsed, .Success = Response.status_code == 200};
+}
+
+ZenCacheResult
 ZenStructuredCacheSession::GetCacheRecord(std::string_view BucketId, const IoHash& Key, ZenContentType Type)
 {
 	ExtendableStringBuilder<256> Uri;
diff --git a/zenserver/upstream/zen.h b/zenserver/upstream/zen.h
index ff4a551bf..36cfd1217 100644
--- a/zenserver/upstream/zen.h
+++ b/zenserver/upstream/zen.h
@@ -109,6 +109,7 @@ public:
 	ZenStructuredCacheSession(ZenStructuredCacheClient& OuterClient);
 	~ZenStructuredCacheSession();
 
+	ZenCacheResult SayHello();
 	ZenCacheResult GetCacheRecord(std::string_view BucketId, const IoHash& Key, ZenContentType Type);
 	ZenCacheResult GetCachePayload(std::string_view BucketId, const IoHash& Key, const IoHash& PayloadId);
 	ZenCacheResult PutCacheRecord(std::string_view BucketId, const IoHash& Key, IoBuffer Value, ZenContentType Type);