Auth Manager API part 1: HTTPRequest, HTTPHeader (#11769)

* Auth Manager API part 1: HTTPRequest, HTTPHeader

* review

* remove static methods

* verify error messages

* checkstyle

* review

* review

* review

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

@@ -0,0 +1,110 @@
+/*
+ * 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.Set;
+import java.util.stream.Collectors;
+import org.apache.iceberg.relocated.com.google.common.base.Preconditions;
+import org.immutables.value.Value;
+
+/**
+ * Represents a group of HTTP headers.
+ *
+ * <p>Header name comparison in this class is always case-insensitive, in accordance with RFC 2616.
+ *
+ * <p>This class exposes methods to convert to and from different representations such as maps and
+ * multimap, for easier access and manipulation – especially when dealing with multiple headers with
+ * the same name.
+ */
+@Value.Style(depluralize = true)
+@Value.Immutable
+@SuppressWarnings({"ImmutablesStyle", "SafeLoggingPropagation"})
+public interface HTTPHeaders {
+
+  HTTPHeaders EMPTY = of();
+
+  /** Returns all the header entries in this group. */
+  Set<HTTPHeader> entries();
+
+  /** Returns all the entries in this group for the given name (case-insensitive). */
+  default Set<HTTPHeader> entries(String name) {
+    return entries().stream()
+        .filter(header -> header.name().equalsIgnoreCase(name))
+        .collect(Collectors.toSet());
+  }
+
+  /** Returns whether this group contains an entry with the given name (case-insensitive). */
+  default boolean contains(String name) {
+    return entries().stream().anyMatch(header -> header.name().equalsIgnoreCase(name));
+  }
+
+  /**
+   * Adds the given header to the current group if no entry with the same name is already present.
+   * Returns a new instance with the added header, or the current instance if the header is already
+   * present.
+   */
+  default HTTPHeaders putIfAbsent(HTTPHeader header) {
+    Preconditions.checkNotNull(header, "header");
+    return contains(header.name())
+        ? this
+        : ImmutableHTTPHeaders.builder().from(this).addEntry(header).build();
+  }
+
+  /**
+   * Adds the given headers to the current group if no entries with same names are already present.
+   * Returns a new instance with the added headers, or the current instance if all headers are
+   * already present.
+   */
+  default HTTPHeaders putIfAbsent(HTTPHeaders headers) {
+    Preconditions.checkNotNull(headers, "headers");
+    List<HTTPHeader> newHeaders =
+        headers.entries().stream().filter(e -> !contains(e.name())).collect(Collectors.toList());
+    return newHeaders.isEmpty()
+        ? this
+        : ImmutableHTTPHeaders.builder().from(this).addAllEntries(newHeaders).build();
+  }
+
+  static HTTPHeaders of(HTTPHeader... headers) {
+    return ImmutableHTTPHeaders.builder().addEntries(headers).build();
+  }
+
+  /** Represents an HTTP header as a name-value pair. */
+  @Value.Style(redactedMask = "****", depluralize = true)
+  @Value.Immutable
+  @SuppressWarnings({"ImmutablesStyle", "SafeLoggingPropagation"})
+  interface HTTPHeader {
+
+    String name();
+
+    @Value.Redacted
+    String value();
+
+    @Value.Check
+    default void check() {
+      if (name().isEmpty()) {
+        throw new IllegalArgumentException("Header name cannot be empty");
+      }
+    }
+
+    static HTTPHeader of(String name, String value) {
+      return ImmutableHTTPHeader.builder().name(name).value(value).build();
+    }
+  }
+}

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

@@ -0,0 +1,126 @@
+/*
+ * 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 com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import java.net.URI;
+import java.net.URISyntaxException;
+import java.util.Map;
+import javax.annotation.Nullable;
+import org.apache.hc.core5.net.URIBuilder;
+import org.apache.iceberg.exceptions.RESTException;
+import org.immutables.value.Value;
+
+/** Represents an HTTP request. */
+@Value.Style(redactedMask = "****", depluralize = true)
+@Value.Immutable
+@SuppressWarnings({"ImmutablesStyle", "SafeLoggingPropagation"})
+public interface HTTPRequest {
+
+  enum HTTPMethod {
+    GET,
+    HEAD,
+    POST,
+    DELETE
+  }
+
+  /**
+   * Returns the base URI configured at the REST client level. The base URI is used to construct the
+   * full {@link #requestUri()}.
+   */
+  URI baseUri();
+
+  /**
+   * Returns the full URI of this request. The URI is constructed from the base URI, path, and query
+   * parameters. It cannot be modified directly.
+   */
+  @Value.Lazy
+  default URI requestUri() {
+    // if full path is provided, use the input path as path
+    String fullPath =
+        (path().startsWith("https://") || path().startsWith("http://"))
+            ? path()
+            : String.format("%s/%s", baseUri(), path());
+    try {
+      URIBuilder builder = new URIBuilder(RESTUtil.stripTrailingSlash(fullPath));
+      queryParameters().forEach(builder::addParameter);
+      return builder.build();
+    } catch (URISyntaxException e) {
+      throw new RESTException(
+          "Failed to create request URI from base %s, params %s", fullPath, queryParameters());
+    }
+  }
+
+  /** Returns the HTTP method of this request. */
+  HTTPMethod method();
+
+  /** Returns the path of this request. */
+  String path();
+
+  /** Returns the query parameters of this request. */
+  Map<String, String> queryParameters();
+
+  /** Returns the headers of this request. */
+  @Value.Default
+  default HTTPHeaders headers() {
+    return HTTPHeaders.EMPTY;
+  }
+
+  /** Returns the raw, unencoded request body. */
+  @Nullable
+  @Value.Redacted
+  Object body();
+
+  /** Returns the encoded request body as a string. */
+  @Value.Lazy
+  @Nullable
+  @Value.Redacted
+  default String encodedBody() {
+    Object body = body();
+    if (body instanceof Map) {
+      return RESTUtil.encodeFormData((Map<?, ?>) body);
+    } else if (body != null) {
+      try {
+        return mapper().writeValueAsString(body);
+      } catch (JsonProcessingException e) {
+        throw new RESTException(e, "Failed to encode request body: %s", body);
+      }
+    }
+    return null;
+  }
+
+  /**
+   * Returns the {@link ObjectMapper} to use for encoding the request body. The default is {@link
+   * RESTObjectMapper#mapper()}.
+   */
+  @Value.Default
+  default ObjectMapper mapper() {
+    return RESTObjectMapper.mapper();
+  }
+
+  @Value.Check
+  default void check() {
+    if (path().startsWith("/")) {
+      throw new RESTException(
+          "Received a malformed path for a REST request: %s. Paths should not start with /",
+          path());
+    }
+  }
+}

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

@@ -0,0 +1,137 @@
+/*
+ * 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.apache.iceberg.rest.HTTPHeaders.HTTPHeader;
+import org.junit.jupiter.api.Test;
+
+class TestHTTPHeaders {
+
+  private final HTTPHeaders headers =
+      HTTPHeaders.of(
+          HTTPHeader.of("header1", "value1a"),
+          HTTPHeader.of("HEADER1", "value1b"),
+          HTTPHeader.of("header2", "value2"));
+
+  @Test
+  void entries() {
+    assertThat(headers.entries())
+        .containsExactlyInAnyOrder(
+            HTTPHeader.of("header1", "value1a"),
+            HTTPHeader.of("HEADER1", "value1b"),
+            HTTPHeader.of("header2", "value2"));
+
+    // duplicated entries
+    assertThat(
+            HTTPHeaders.of(HTTPHeader.of("header1", "value1"), HTTPHeader.of("header1", "value1"))
+                .entries())
+        .containsExactly(HTTPHeader.of("header1", "value1"));
+  }
+
+  @Test
+  void entriesByName() {
+    assertThat(headers.entries("header1"))
+        .containsExactlyInAnyOrder(
+            HTTPHeader.of("header1", "value1a"), HTTPHeader.of("HEADER1", "value1b"));
+    assertThat(headers.entries("HEADER1"))
+        .containsExactlyInAnyOrder(
+            HTTPHeader.of("header1", "value1a"), HTTPHeader.of("HEADER1", "value1b"));
+    assertThat(headers.entries("header2"))
+        .containsExactlyInAnyOrder(HTTPHeader.of("header2", "value2"));
+    assertThat(headers.entries("HEADER2"))
+        .containsExactlyInAnyOrder(HTTPHeader.of("header2", "value2"));
+    assertThat(headers.entries("header3")).isEmpty();
+    assertThat(headers.entries("HEADER3")).isEmpty();
+    assertThat(headers.entries(null)).isEmpty();
+  }
+
+  @Test
+  void contains() {
+    assertThat(headers.contains("header1")).isTrue();
+    assertThat(headers.contains("HEADER1")).isTrue();
+    assertThat(headers.contains("header2")).isTrue();
+    assertThat(headers.contains("HEADER2")).isTrue();
+    assertThat(headers.contains("header3")).isFalse();
+    assertThat(headers.contains("HEADER3")).isFalse();
+    assertThat(headers.contains(null)).isFalse();
+  }
+
+  @Test
+  void putIfAbsentHTTPHeader() {
+    HTTPHeaders actual = headers.putIfAbsent(HTTPHeader.of("Header1", "value1c"));
+    assertThat(actual).isSameAs(headers);
+
+    actual = headers.putIfAbsent(HTTPHeader.of("header3", "value3"));
+    assertThat(actual.entries())
+        .containsExactly(
+            HTTPHeader.of("header1", "value1a"),
+            HTTPHeader.of("HEADER1", "value1b"),
+            HTTPHeader.of("header2", "value2"),
+            HTTPHeader.of("header3", "value3"));
+
+    assertThatThrownBy(() -> headers.putIfAbsent((HTTPHeader) null))
+        .isInstanceOf(NullPointerException.class)
+        .hasMessage("header");
+  }
+
+  @Test
+  void putIfAbsentHTTPHeaders() {
+    HTTPHeaders actual = headers.putIfAbsent(HTTPHeaders.of(HTTPHeader.of("Header1", "value1c")));
+    assertThat(actual).isSameAs(headers);
+
+    actual =
+        headers.putIfAbsent(
+            ImmutableHTTPHeaders.builder()
+                .addEntry(HTTPHeader.of("Header1", "value1c"))
+                .addEntry(HTTPHeader.of("header3", "value3"))
+                .build());
+    assertThat(actual)
+        .isEqualTo(
+            ImmutableHTTPHeaders.builder()
+                .addEntries(
+                    HTTPHeader.of("header1", "value1a"),
+                    HTTPHeader.of("HEADER1", "value1b"),
+                    HTTPHeader.of("header2", "value2"),
+                    HTTPHeader.of("header3", "value3"))
+                .build());
+
+    assertThatThrownBy(() -> headers.putIfAbsent((HTTPHeaders) null))
+        .isInstanceOf(NullPointerException.class)
+        .hasMessage("headers");
+  }
+
+  @Test
+  void invalidHeader() {
+    // invalid input (null name or value)
+    assertThatThrownBy(() -> HTTPHeader.of(null, "value1"))
+        .isInstanceOf(NullPointerException.class)
+        .hasMessage("name");
+    assertThatThrownBy(() -> HTTPHeader.of("header1", null))
+        .isInstanceOf(NullPointerException.class)
+        .hasMessage("value");
+
+    // invalid input (empty name)
+    assertThatThrownBy(() -> HTTPHeader.of("", "value1"))
+        .isInstanceOf(IllegalArgumentException.class)
+        .hasMessage("Header name cannot be empty");
+  }
+}