[#1] Define SDK structure, add operations with container and object

Signed-off-by: Ori Bruk <o.bruk@yadro.com>

client/src/main/java/info/FrostFS/sdk/GrpcClient.java

@@ -0,0 +1,89 @@
+package info.FrostFS.sdk;
+
+import frostFS.container.ContainerServiceGrpc;
+import frostFS.netmap.NetmapServiceGrpc;
+import frostFS.object.ObjectServiceGrpc;
+import frostFS.session.SessionServiceGrpc;
+import io.grpc.Channel;
+import io.grpc.netty.GrpcSslContexts;
+import io.grpc.netty.NettyChannelBuilder;
+import io.netty.handler.ssl.util.InsecureTrustManagerFactory;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import javax.net.ssl.SSLException;
+import java.net.URI;
+import java.net.URISyntaxException;
+
+public class GrpcClient {
+    private static final Logger log = LoggerFactory.getLogger(GrpcClient.class);
+
+    private final ContainerServiceGrpc.ContainerServiceBlockingStub containerServiceBlockingClient;
+    private final NetmapServiceGrpc.NetmapServiceBlockingStub netmapServiceBlockingClient;
+    private final ObjectServiceGrpc.ObjectServiceBlockingStub objectServiceBlockingClient;
+    private final ObjectServiceGrpc.ObjectServiceStub objectServiceClient;
+    private final SessionServiceGrpc.SessionServiceBlockingStub sessionServiceBlockingClient;
+
+    public GrpcClient(String host) {
+        Channel channel = initGrpcChannel(host);
+        this.containerServiceBlockingClient = ContainerServiceGrpc.newBlockingStub(channel);
+        this.netmapServiceBlockingClient = NetmapServiceGrpc.newBlockingStub(channel);
+        this.objectServiceBlockingClient = ObjectServiceGrpc.newBlockingStub(channel);
+        this.objectServiceClient = ObjectServiceGrpc.newStub(channel);
+        this.sessionServiceBlockingClient = SessionServiceGrpc.newBlockingStub(channel);
+    }
+
+    public static Channel initGrpcChannel(String host) {
+        URI uri;
+        try {
+            uri = new URI(host);
+        } catch (URISyntaxException exp) {
+            var message = String.format("Host %s has invalid format. Error: %s", host, exp.getMessage());
+            log.error(message);
+            throw new IllegalArgumentException(message);
+        }
+
+        var channelBuilder = NettyChannelBuilder.forAddress(uri.getHost(), uri.getPort())
+                .usePlaintext();
+
+        switch (uri.getScheme()) {
+            case "https":
+                try {
+                    channelBuilder.sslContext(
+                            GrpcSslContexts.forClient().trustManager(InsecureTrustManagerFactory.INSTANCE).build()
+                    );
+                } catch (SSLException e) {
+                    throw new RuntimeException(e);
+                }
+                break;
+            case "http":
+                break;
+            default:
+                var message = String.format("Host %s  has invalid URI scheme: %s", host, uri.getScheme());
+                log.error(message);
+                throw new IllegalArgumentException(message);
+        }
+
+        return channelBuilder.build();
+    }
+
+    public ContainerServiceGrpc.ContainerServiceBlockingStub getContainerServiceBlockingClient() {
+        return containerServiceBlockingClient;
+    }
+
+    public NetmapServiceGrpc.NetmapServiceBlockingStub getNetmapServiceBlockingClient() {
+        return netmapServiceBlockingClient;
+    }
+
+    public ObjectServiceGrpc.ObjectServiceBlockingStub getObjectServiceBlockingClient() {
+        return objectServiceBlockingClient;
+    }
+
+    public ObjectServiceGrpc.ObjectServiceStub getObjectServiceClient() {
+        return objectServiceClient;
+    }
+
+    public SessionServiceGrpc.SessionServiceBlockingStub getSessionServiceBlockingClient() {
+        return sessionServiceBlockingClient;
+    }
+}