4.x: double-slash URI issue helidon-io#7474 (helidon-io#7657)

* Double-slash URI issue helidon-io#7474

* Flaky test fix

* Review issues 2

Author: danielkec

common/uri/src/main/java/io/helidon/common/uri/UriPathNoParam.java

@@ -73,7 +73,7 @@ public String rawPathNoParams() {
     @Override
     public String path() {
         if (decodedPath == null) {
-            decodedPath = decode(rawPath);
+            decodedPath = decode(rawPath, false);
         }
         return decodedPath;
     }
@@ -104,11 +104,11 @@ public String toString() {
     @Override
     public void validate() {
         if (decodedPath == null) {
-            this.decodedPath = URI.create(rawPath).normalize().getPath();
+            this.decodedPath = decode(rawPath, true);
         }
     }
 
-    private static String decode(String rawPath) {
+    private static String decode(String rawPath, boolean validate) {
         /*
         Raw path may:
          - be encoded (%20)
@@ -121,10 +121,18 @@ private static String decode(String rawPath) {
         int dot = rawPath.indexOf(".");
         int doubleSlash = rawPath.indexOf("//");
 
-        if (percent == -1 && doubleSlash == -1 && dot == -1) {
+        if (!validate && percent == -1 && doubleSlash == -1 && dot == -1) {
             return rawPath;
         }
 
+        if (doubleSlash == 0) {
+            /*
+            RFC2396 - net_path starts with //, that would lead to loosing first path segment.
+            example: URI.create("//foo/bar").getPath() --> "/bar"
+            */
+            rawPath = rawPath.substring(1);
+        }
+
         return URI.create(rawPath).normalize().getPath();
     }
 }

common/uri/src/test/java/io/helidon/common/uri/UriPathTest.java

@@ -17,6 +17,8 @@
 package io.helidon.common.uri;
 
 import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
 
 import static org.hamcrest.CoreMatchers.is;
 import static org.hamcrest.MatcherAssert.assertThat;
@@ -37,4 +39,16 @@ void testEncodeSpace() {
         assertThat(path.path(), is("/my path"));
         assertThat(path.rawPath(), is("/my%20path"));
     }
+
+    @ParameterizedTest
+    @ValueSource(strings = {
+            "//foo/bar",
+            "//foo//bar",
+            "/foo//bar",
+            "/foo/bar",
+    })
+    void testDoubleSlash(String rawPath) {
+        UriPath path = UriPath.create(rawPath);
+        assertThat(path.path(), is("/foo/bar"));
+    }
 }

webclient/tests/webclient/src/test/java/io/helidon/webclient/tests/TracingPropagationTest.java

@@ -59,6 +59,8 @@
 class TracingPropagationTest {
     private static final Duration TIMEOUT = Duration.ofSeconds(15);
     private static final AtomicReference<CountDownLatch> SPAN_COUNT_LATCH = new AtomicReference<>();
+    // 2+1 after re-introduction of content-write span
+    private static final int EXPECTED_NUMBER_OF_SPANS = 3;
     private static MockTracer tracer;
     private final Http1Client client;
     private final URI uri;
@@ -92,7 +94,7 @@ protected void onSpanFinished(MockSpan mockSpan) {
 
     @Test
     void testTracingSuccess() throws InterruptedException {
-        SPAN_COUNT_LATCH.set(new CountDownLatch(2));
+        SPAN_COUNT_LATCH.set(new CountDownLatch(EXPECTED_NUMBER_OF_SPANS));
         Context context = Context.builder().id("tracing-unit-test").build();
         context.register(tracer);
 
@@ -110,10 +112,7 @@ void testTracingSuccess() throws InterruptedException {
         List<MockSpan> mockSpans = tracer.finishedSpans();
 
         // the server traces asynchronously, some spans may be written after we receive the response.
-        // we need to try to wait for such spans
-        // re-introduced content-write span
-        assertThat("There should be 3 spans reported", tracer.finishedSpans(), hasSize(3));
-
+        assertThat("There should be 3 spans reported", tracer.finishedSpans(), hasSize(EXPECTED_NUMBER_OF_SPANS));
 
         // we need the first span - parentId 0
         MockSpan clientSpan = findSpanWithParentId(mockSpans, 0);