Core: Allow servers to express supported endpoints via endpoint field in ConfigResponse

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

@@ -0,0 +1,161 @@
+/*
+ * 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 java.util.List;
+import java.util.Objects;
+import java.util.Set;
+import org.apache.hc.core5.http.Method;
+import org.apache.iceberg.relocated.com.google.common.base.Joiner;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.apache.iceberg.relocated.com.google.common.base.Splitter;
+import org.apache.iceberg.relocated.com.google.common.base.Strings;
+import org.apache.iceberg.relocated.com.google.common.base.Supplier;
+
+/**
+ * Holds an endpoint definition that consists of the HTTP method (GET, POST, DELETE, ...) and the
+ * resource path as defined in the Iceberg OpenAPI REST specification without parameter
+ * substitution, such as <b>/v1/{prefix}/namespaces/{namespace}</b>.
+ */
+public class Endpoint {
+
+  // namespace endpoints
+  public static final Endpoint V1_LIST_NAMESPACES =
+      Endpoint.create("GET", ResourcePaths.V1_NAMESPACES);
+  public static final Endpoint V1_LOAD_NAMESPACE =
+      Endpoint.create("GET", ResourcePaths.V1_NAMESPACE);
+  public static final Endpoint V1_CREATE_NAMESPACE =
+      Endpoint.create("POST", ResourcePaths.V1_NAMESPACES);
+  public static final Endpoint V1_UPDATE_NAMESPACE =
+      Endpoint.create("POST", ResourcePaths.V1_NAMESPACE_PROPERTIES);
+  public static final Endpoint V1_DELETE_NAMESPACE =
+      Endpoint.create("DELETE", ResourcePaths.V1_NAMESPACE);
+  public static final Endpoint V1_COMMIT_TRANSACTION =
+      Endpoint.create("POST", ResourcePaths.V1_TRANSACTIONS_COMMIT);
+
+  // table endpoints
+  public static final Endpoint V1_LIST_TABLES = Endpoint.create("GET", ResourcePaths.V1_TABLES);
+  public static final Endpoint V1_LOAD_TABLE = Endpoint.create("GET", ResourcePaths.V1_TABLE);
+  public static final Endpoint V1_CREATE_TABLE = Endpoint.create("POST", ResourcePaths.V1_TABLES);
+  public static final Endpoint V1_UPDATE_TABLE = Endpoint.create("POST", ResourcePaths.V1_TABLE);
+  public static final Endpoint V1_DELETE_TABLE = Endpoint.create("DELETE", ResourcePaths.V1_TABLE);
+  public static final Endpoint V1_RENAME_TABLE =
+      Endpoint.create("POST", ResourcePaths.V1_TABLE_RENAME);
+  public static final Endpoint V1_REGISTER_TABLE =
+      Endpoint.create("POST", ResourcePaths.V1_TABLE_REGISTER);
+  public static final Endpoint V1_REPORT_METRICS =
+      Endpoint.create("POST", ResourcePaths.V1_TABLE_METRICS);
+
+  // view endpoints
+  public static final Endpoint V1_LIST_VIEWS = Endpoint.create("GET", ResourcePaths.V1_VIEWS);
+  public static final Endpoint V1_LOAD_VIEW = Endpoint.create("GET", ResourcePaths.V1_VIEW);
+  public static final Endpoint V1_CREATE_VIEW = Endpoint.create("POST", ResourcePaths.V1_VIEWS);
+  public static final Endpoint V1_UPDATE_VIEW = Endpoint.create("POST", ResourcePaths.V1_VIEW);
+  public static final Endpoint V1_DELETE_VIEW = Endpoint.create("DELETE", ResourcePaths.V1_VIEW);
+  public static final Endpoint V1_RENAME_VIEW =
+      Endpoint.create("POST", ResourcePaths.V1_VIEW_RENAME);
+
+  private static final Splitter ENDPOINT_SPLITTER = Splitter.on(" ");
+  private static final Joiner ENDPOINT_JOINER = Joiner.on(" ");
+  private final String httpMethod;
+  private final String path;
+
+  private Endpoint(String httpMethod, String path) {
+    Preconditions.checkArgument(
+        !Strings.isNullOrEmpty(httpMethod), "Invalid HTTP method: null or empty");
+    Preconditions.checkArgument(!Strings.isNullOrEmpty(path), "Invalid path: null or empty");
+    this.httpMethod = Method.normalizedValueOf(httpMethod).toString();
+    this.path = path;
+  }
+
+  public String httpMethod() {
+    return httpMethod;
+  }
+
+  public String path() {
+    return path;
+  }
+
+  public static Endpoint create(String httpMethod, String path) {
+    return new Endpoint(httpMethod, path);
+  }
+
+  @Override
+  public String toString() {
+    return ENDPOINT_JOINER.join(httpMethod(), path());
+  }
+
+  public static Endpoint fromString(String endpoint) {
+    List<String> elements = ENDPOINT_SPLITTER.splitToList(endpoint);
+    Preconditions.checkArgument(
+        elements.size() == 2,
+        "Invalid endpoint (must consist of two elements separated by a single space): %s",
+        endpoint);
+    return create(elements.get(0), elements.get(1));
+  }
+
+  /**
+   * Checks if the set of endpoints support the given {@link Endpoint}.
+   *
+   * @param supportedEndpoints The set of supported endpoints to check
+   * @param endpoint The endpoint to check against the set of supported endpoints
+   * @throws UnsupportedOperationException if the given {@link Endpoint} is not included in the set
+   *     of endpoints.
+   */
+  public static void check(Set<Endpoint> supportedEndpoints, Endpoint endpoint) {
+    if (!supportedEndpoints.contains(endpoint)) {
+      throw new UnsupportedOperationException(
+          String.format("Server does not support endpoint: %s", endpoint));
+    }
+  }
+
+  /**
+   * Checks if the set of endpoints support the given {@link Endpoint}.
+   *
+   * @param supportedEndpoints The set of supported endpoints to check
+   * @param endpoint The endpoint to check against the set of supported endpoints
+   * @param supplier The supplier throwing a {@link RuntimeException} if the given {@link Endpoint}
+   *     is not included in the set of endpoints.
+   */
+  public static void check(
+      Set<Endpoint> supportedEndpoints, Endpoint endpoint, Supplier<RuntimeException> supplier) {
+    if (!supportedEndpoints.contains(endpoint)) {
+      throw supplier.get();
+    }
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (this == o) {
+      return true;
+    }
+
+    if (!(o instanceof Endpoint)) {
+      return false;
+    }
+
+    Endpoint endpoint = (Endpoint) o;
+    return Objects.equals(httpMethod, endpoint.httpMethod) && Objects.equals(path, endpoint.path);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(httpMethod, path);
+  }
+}