add option to choose client/server side linerizability

scripts/functions.sh

@@ -27,7 +27,7 @@ function quit {
 
 function start {
   echo -e "Starting first server."
-  dgraph server -p build/p -w build/w --memory_mb 4096 --zero localhost:5080 > build/server.log 2>&1 &
+  dgraph server -p build/p -w build/w --lru_mb 4096 --zero localhost:5080 > build/server.log 2>&1 &
   # Wait for membership sync to happen.
   sleep $sleepTime
   return 0

src/main/java/io/dgraph/DgraphClient.java

@@ -171,9 +171,20 @@ public class Transaction implements AutoCloseable {
     TxnContext context;
     boolean finished;
     boolean mutated;
+    LinRead.Sequencing sequencing;
 
     Transaction() {
       context = TxnContext.newBuilder().setLinRead(DgraphClient.this.getLinRead()).build();
+      sequencing = LinRead.Sequencing.CLIENT_SIDE;
+    }
+
+    /**
+     * Sets the sequencing for this transaction. By default client_side_sequencing is used
+     *
+     * @param sequencing Sequencing Mode (ClIENT_SIDE or SERVER_SIDE).
+     */
+    public void setSequencing(LinRead.Sequencing sequencing) {
+      this.sequencing = sequencing;
     }
 
     /**
@@ -187,12 +198,14 @@ public class Transaction implements AutoCloseable {
      */
     public Response queryWithVars(final String query, final Map<String, String> vars) {
       logger.debug("Starting query...");
+      LinRead.Builder lr = LinRead.newBuilder(context.getLinRead());
+      lr.setSequencing(this.sequencing);
       final Request request =
           Request.newBuilder()
               .setQuery(query)
               .putAllVars(vars)
               .setStartTs(context.getStartTs())
-              .setLinRead(context.getLinRead())
+              .setLinRead(lr.build())
               .build();
       final DgraphGrpc.DgraphBlockingStub client = anyClient();
       logger.debug("Sending request to Dgraph...");

src/main/proto/api.proto

@@ -48,6 +48,7 @@ message Response {
 message Assigned {
 	map<string, string> uids = 1;
 	TxnContext context = 2;
+	Latency latency = 12;
 }
 
 message Mutation {
@@ -60,7 +61,7 @@ message Mutation {
 	repeated NQuad del = 11;
 	uint64 start_ts = 13;
 	bool commit_now = 14;
-	bool ignore_index_conflict = 15;
+	bool ignore_index_conflict = 15; // this field is not parsed or used by the server anymore.
 }
 
 
@@ -95,7 +96,13 @@ message Version {
 }
 
 message LinRead {
+	enum Sequencing {
+		CLIENT_SIDE = 0;
+		SERVER_SIDE = 1;
+	}
+
 	map<uint32, uint64> ids = 1;
+	Sequencing sequencing = 2;
 }
 
 message Latency {
@@ -154,6 +161,8 @@ message SchemaNode {
 	bool reverse = 5;
 	bool count = 6;
 	bool list = 7;
+	bool upsert = 8;
+	bool lang = 9;
 }
 
 // vim: noexpandtab sw=2 ts=2

src/test/java/io/dgraph/AcctUpsertTest.java

@@ -44,9 +44,9 @@ private void setup() {
 
     String schema =
         "\n"
-            + "   first:  string   @index(term) .\n"
-            + "   last:   string   @index(hash) .\n"
-            + "   age:    int      @index(int)  .\n"
+            + "   first:  string   @index(term) @upsert .\n"
+            + "   last:   string   @index(hash) @upsert .\n"
+            + "   age:    int      @index(int)  @upsert .\n"
             + "   when:   int                   .\n";
     Operation op = Operation.newBuilder().setSchema(schema).build();
     dgraphClient.alter(op);

src/test/java/io/dgraph/DeleteEdgeTest.java

@@ -69,7 +69,7 @@ public void deleteEdgesTest() {
             + "   }\n"
             + "   schools {\n"
             + "    uid\n"
-            + "    name@en\n"
+            + "    name\n"
             + "   }\n"
             + "  }\n"
             + " }";

src/test/java/io/dgraph/DgraphClientTest.java

@@ -82,7 +82,7 @@ public void testMergeContext() throws Exception {
   @Test
   public void testTxnQueryVariables() throws Exception {
     // Set schema
-    Operation op = Operation.newBuilder().setSchema("name: string @index(exact) .").build();
+    Operation op = Operation.newBuilder().setSchema("name: string @index(exact) @upsert .").build();
     dgraphClient.alter(op);
 
     // Add data
@@ -173,7 +173,7 @@ public void testClientWithDeadline() throws Exception {
     DgraphGrpc.DgraphBlockingStub blockingStub = DgraphGrpc.newBlockingStub(channel);
     dgraphClient = new DgraphClient(Collections.singletonList(blockingStub), 1);
 
-    Operation op = Operation.newBuilder().setSchema("name: string @index(exact) .").build();
+    Operation op = Operation.newBuilder().setSchema("name: string @index(exact) @upsert .").build();
 
     // Alters schema without exceeding the given deadline.
     dgraphClient.alter(op);

src/test/java/io/dgraph/MutatesTest.java

@@ -20,7 +20,8 @@ public class MutatesTest extends DgraphIntegrationTest {
 
   @Test
   public void testInsert3Quads() throws Exception {
-    Operation op = Operation.newBuilder().setSchema("name: string @index(fulltext) .").build();
+    Operation op =
+        Operation.newBuilder().setSchema("name: string @index(fulltext) @upsert .").build();
     dgraphClient.alter(op);
 
     Transaction txn = dgraphClient.newTransaction();