okhttp: Support GET in okhttp transport

okhttp/src/main/java/io/grpc/okhttp/OkHttpClientStream.java

@@ -34,6 +34,7 @@ package io.grpc.okhttp;
 import static com.google.common.base.Preconditions.checkNotNull;
 import static com.google.common.base.Preconditions.checkState;
 
+import com.google.common.io.BaseEncoding;
 import io.grpc.Attributes;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
@@ -83,7 +84,7 @@ class OkHttpClientStream extends AbstractClientStream2 {
       String authority,
       String userAgent,
       StatsTraceContext statsTraceCtx) {
-    super(new OkHttpWritableBufferAllocator(), statsTraceCtx, headers, false);
+    super(new OkHttpWritableBufferAllocator(), statsTraceCtx, headers, method.isSafe());
     this.statsTraceCtx = checkNotNull(statsTraceCtx, "statsTraceCtx");
     this.method = method;
     this.authority = authority;
@@ -127,6 +128,9 @@ class OkHttpClientStream extends AbstractClientStream2 {
     @Override
     public void writeHeaders(Metadata metadata, byte[] payload) {
       String defaultPath = "/" + method.getFullMethodName();
+      if (payload != null) {
+        defaultPath += "?" + BaseEncoding.base64().encode(payload);
+      }
       metadata.discardAll(GrpcUtil.USER_AGENT_KEY);
       synchronized (state.lock) {
         state.streamReady(metadata, defaultPath);

okhttp/src/test/java/io/grpc/okhttp/OkHttpClientStreamTest.java

@@ -35,9 +35,12 @@ import static com.google.common.truth.Truth.assertThat;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 import static org.mockito.Matchers.eq;
+import static org.mockito.Matchers.isA;
+import static org.mockito.Mockito.times;
 import static org.mockito.Mockito.verify;
 import static org.mockito.Mockito.verifyNoMoreInteractions;
 
+import com.google.common.io.BaseEncoding;
 import io.grpc.Metadata;
 import io.grpc.MethodDescriptor;
 import io.grpc.MethodDescriptor.MethodType;
@@ -47,7 +50,9 @@ import io.grpc.internal.GrpcUtil;
 import io.grpc.internal.StatsTraceContext;
 import io.grpc.okhttp.internal.framed.ErrorCode;
 import io.grpc.okhttp.internal.framed.Header;
+import java.io.ByteArrayInputStream;
 import java.io.InputStream;
+import java.nio.charset.Charset;
 import java.util.List;
 import java.util.concurrent.atomic.AtomicReference;
 import org.junit.Before;
@@ -176,6 +181,38 @@ public class OkHttpClientStreamTest {
             .inOrder();
   }
 
+  @Test
+  public void getUnaryRequest() {
+    MethodDescriptor<?, ?> getMethod = MethodDescriptor.<Void, Void>newBuilder()
+        .setType(MethodDescriptor.MethodType.UNARY)
+        .setFullMethodName("/service/method")
+        .setIdempotent(true)
+        .setSafe(true)
+        .setRequestMarshaller(marshaller)
+        .setResponseMarshaller(marshaller)
+        .build();
+    stream = new OkHttpClientStream(getMethod, new Metadata(), frameWriter, transport,
+        flowController, lock, MAX_MESSAGE_SIZE, "localhost", "good-application",
+        StatsTraceContext.NOOP);
+    stream.start(new BaseClientStreamListener());
+
+    // GET streams send headers after halfClose is called.
+    verify(frameWriter, times(0)).synStream(
+        eq(false), eq(false), eq(3), eq(0), headersCaptor.capture());
+    verify(transport, times(0)).streamReadyToStart(isA(OkHttpClientStream.class));
+
+    byte[] msg = "request".getBytes(Charset.forName("UTF-8"));
+    stream.writeMessage(new ByteArrayInputStream(msg));
+    stream.halfClose();
+    verify(transport).streamReadyToStart(eq(stream));
+    stream.transportState().start(3);
+
+    verify(frameWriter).synStream(eq(false), eq(false), eq(3), eq(0), headersCaptor.capture());
+    assertThat(headersCaptor.getValue()).contains(
+        new Header(Header.TARGET_PATH, "/" + getMethod.getFullMethodName() + "?"
+            + BaseEncoding.base64().encode(msg)));
+  }
+
   // TODO(carl-mastrangelo): extract this out into a testing/ directory and remove other definitions
   // of it.
   private static class BaseClientStreamListener implements ClientStreamListener {