add flag to assume view endpoint support + some tests

core/src/main/java/org/apache/iceberg/rest/RESTSessionCatalog.java

@@ -116,6 +116,9 @@ public class RESTSessionCatalog extends BaseViewSessionCatalog
   private static final String DEFAULT_FILE_IO_IMPL = "org.apache.iceberg.io.ResolvingFileIO";
   private static final String REST_METRICS_REPORTING_ENABLED = "rest-metrics-reporting-enabled";
   private static final String REST_SNAPSHOT_LOADING_MODE = "snapshot-loading-mode";
+  // for backwards compatibility with older REST servers where it can be assumed that a particular
+  // server supports view endpoints but doesn't send the "endpoints" field in the ConfigResponse
+  private static final String VIEW_ENDPOINTS_SUPPORTED = "view-endpoints-supported";
   public static final String REST_PAGE_SIZE = "rest-page-size";
   private static final List<String> TOKEN_PREFERENCE_ORDER =
       ImmutableList.of(
@@ -149,6 +152,16 @@ public class RESTSessionCatalog extends BaseViewSessionCatalog
           .add(ResourcePaths.V1_REPORT_METRICS)
           .build();
 
+  private static final Set<Endpoint> VIEW_ENDPOINTS =
+      ImmutableSet.<Endpoint>builder()
+          .add(ResourcePaths.V1_LIST_VIEWS)
+          .add(ResourcePaths.V1_LOAD_VIEW)
+          .add(ResourcePaths.V1_CREATE_VIEW)
+          .add(ResourcePaths.V1_UPDATE_VIEW)
+          .add(ResourcePaths.V1_DELETE_VIEW)
+          .add(ResourcePaths.V1_RENAME_VIEW)
+          .build();
+
   private final Function<Map<String, String>, RESTClient> clientBuilder;
   private final BiFunction<SessionContext, Map<String, String>, FileIO> ioBuilder;
   private Cache<String, AuthSession> sessions = null;
@@ -247,8 +260,17 @@ public void initialize(String name, Map<String, String> unresolved) {
     // build the final configuration and set up the catalog's auth
     Map<String, String> mergedProps = config.merge(props);
     Map<String, String> baseHeaders = configHeaders(mergedProps);
-    this.endpoints =
-        config.endpoints().isEmpty() ? DEFAULT_ENDPOINTS : ImmutableSet.copyOf(config.endpoints());
+    if (config.endpoints().isEmpty()) {
+      this.endpoints =
+          PropertyUtil.propertyAsBoolean(mergedProps, VIEW_ENDPOINTS_SUPPORTED, false)
+              ? ImmutableSet.<Endpoint>builder()
+                  .addAll(DEFAULT_ENDPOINTS)
+                  .addAll(VIEW_ENDPOINTS)
+                  .build()
+              : DEFAULT_ENDPOINTS;
+    } else {
+      this.endpoints = ImmutableSet.copyOf(config.endpoints());
+    }
 
     this.sessions = newSessionCache(mergedProps);
     this.tableSessions = newSessionCache(mergedProps);

core/src/test/java/org/apache/iceberg/rest/TestEndpoint.java

@@ -0,0 +1,74 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.iceberg.rest;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
+
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+public class TestEndpoint {
+  @Test
+  public void nullOrEmptyValues() {
+    assertThatThrownBy(() -> Endpoint.create(null, "endpoint"))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage("Invalid HTTP method: null or empty");
+
+    assertThatThrownBy(() -> Endpoint.create("", "endpoint"))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage("Invalid HTTP method: null or empty");
+
+    assertThatThrownBy(() -> Endpoint.create("GET", null))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage("Invalid path: null or empty");
+
+    assertThatThrownBy(() -> Endpoint.create("GET", ""))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage("Invalid path: null or empty");
+  }
+
+  @ParameterizedTest
+  @ValueSource(strings = {"/path", " GET /path", "GET /path ", "GET  /path"})
+  public void invalidFromString(String endpoint) {
+    assertThatThrownBy(() -> Endpoint.fromString(endpoint))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage(
+            "Invalid endpoint (must consist of two elements separated by space): %s", endpoint);
+  }
+
+  @Test
+  public void validFromString() {
+    Endpoint endpoint = Endpoint.fromString("GET /path");
+    assertThat(endpoint.httpMethod()).isEqualTo("GET");
+    assertThat(endpoint.path()).isEqualTo("/path");
+  }
+
+  @Test
+  public void toStringRepresentation() {
+    assertThat(Endpoint.create("POST", "/path/of/resource"))
+        .asString()
+        .isEqualTo("POST /path/of/resource");
+    assertThat(Endpoint.create("GET", "/")).asString().isEqualTo("GET /");
+    assertThat(Endpoint.create("PUT", "/namespaces/{namespace}/{x}"))
+        .asString()
+        .isEqualTo("PUT /namespaces/{namespace}/{x}");
+  }
+}