#1140 RsHeaders

src/main/java/org/takes/rq/RqHeaders.java

@@ -44,7 +44,7 @@
 import org.takes.misc.VerboseList;
 
 /**
- * HTTP headers parsing
+ * HTTP headers parsing.
  *
  * <p>All implementations of this interface must be immutable and
  * thread-safe.</p>

src/main/java/org/takes/rs/RsHeaders.java

@@ -0,0 +1,264 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2014-2022 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.takes.rs;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.LinkedList;
+import java.util.List;
+import java.util.Map;
+import java.util.Set;
+import lombok.EqualsAndHashCode;
+import org.cactoos.text.FormattedText;
+import org.cactoos.text.Lowered;
+import org.cactoos.text.TextOf;
+import org.cactoos.text.Trimmed;
+import org.cactoos.text.UncheckedText;
+import org.takes.HttpException;
+import org.takes.Response;
+import org.takes.misc.VerboseList;
+
+/**
+ * HTTP headers parsing.
+ *
+ * <p>All implementations of this interface must be immutable and
+ * thread-safe.</p>
+ *
+ * @since 0.1
+ */
+@SuppressWarnings("PMD.TooManyMethods")
+public interface RsHeaders extends Response {
+
+    /**
+     * Get single header.
+     *
+     * @param key Header name
+     * @return List of values (can be empty)
+     * @throws IOException If fails
+     */
+    List<String> header(CharSequence key) throws IOException;
+
+    /**
+     * Get all header names.
+     *
+     * @return All names
+     * @throws IOException If fails
+     */
+    Set<String> names() throws IOException;
+
+    /**
+     * Request decorator, for HTTP headers parsing.
+     *
+     * <p>The class is immutable and thread-safe.
+     *
+     * @since 0.13.8
+     */
+    @EqualsAndHashCode(callSuper = true)
+    final class Base extends RsWrap implements RsHeaders {
+        /**
+         * Ctor.
+         *
+         * @param req Original request
+         */
+        public Base(final Response req) {
+            super(req);
+        }
+
+        @Override
+        public List<String> header(final CharSequence key)
+            throws IOException {
+            final List<String> values = this.map().getOrDefault(
+                new UncheckedText(
+                    new Lowered(key.toString())
+                ).asString(),
+                Collections.emptyList()
+            );
+            final List<String> list;
+            if (values.isEmpty()) {
+                list = new VerboseList<>(
+                    Collections.emptyList(),
+                    new FormattedText(
+                        "there are no headers by name \"%s\" among %d others: %s",
+                        key,
+                        this.map().size(),
+                        this.map().keySet()
+                    )
+                );
+            } else {
+                list = new VerboseList<>(
+                    values,
+                    new FormattedText(
+                        "there are only %d headers by name \"%s\"",
+                        values.size(),
+                        key
+                    )
+                );
+            }
+            return list;
+        }
+
+        @Override
+        public Set<String> names() throws IOException {
+            return this.map().keySet();
+        }
+
+        /**
+         * Parse them all in a map.
+         *
+         * @return Map of them
+         * @throws IOException If fails
+         */
+        @SuppressWarnings("PMD.AvoidInstantiatingObjectsInLoops")
+        private Map<String, List<String>> map() throws IOException {
+            final Iterator<String> head = this.head().iterator();
+            if (!head.hasNext()) {
+                throw new HttpException(
+                    HttpURLConnection.HTTP_BAD_REQUEST,
+                    "a valid request must contain at least one line in the head"
+                );
+            }
+            head.next();
+            final Map<String, List<String>> map = new HashMap<>(0);
+            while (head.hasNext()) {
+                final String line = head.next();
+                final String[] parts = line.split(":", 2);
+                if (parts.length < 2) {
+                    throw new HttpException(
+                        HttpURLConnection.HTTP_BAD_REQUEST,
+                        String.format("invalid HTTP header: \"%s\"", line)
+                    );
+                }
+                final String key = new UncheckedText(
+                    new Lowered(new Trimmed(new TextOf(parts[0])))
+                ).asString();
+                if (!map.containsKey(key)) {
+                    map.put(key, new LinkedList<>());
+                }
+                map.get(key).add(
+                    new UncheckedText(
+                        new Trimmed(new TextOf(parts[1]))
+                    ).asString()
+                );
+            }
+            return map;
+        }
+    }
+
+    /**
+     * Smart decorator, with extra features.
+     *
+     * <p>The class is immutable and thread-safe.
+     *
+     * @since 0.16
+     */
+    @EqualsAndHashCode
+    final class Smart implements RsHeaders {
+        /**
+         * Original.
+         */
+        private final RsHeaders origin;
+
+        /**
+         * Ctor.
+         * @param req Original request
+         */
+        public Smart(final RsHeaders req) {
+            this.origin = req;
+        }
+
+        /**
+         * Ctor.
+         * @param req Original request
+         */
+        public Smart(final Response req) {
+            this(new RsHeaders.Base(req));
+        }
+
+        @Override
+        public List<String> header(final CharSequence name)
+            throws IOException {
+            return this.origin.header(name);
+        }
+
+        @Override
+        public Set<String> names() throws IOException {
+            return this.origin.names();
+        }
+
+        @Override
+        public Iterable<String> head() throws IOException {
+            return this.origin.head();
+        }
+
+        @Override
+        public InputStream body() throws IOException {
+            return this.origin.body();
+        }
+
+        /**
+         * Get single header or throw HTTP exception.
+         * @param name Name of header
+         * @return Value of it
+         * @throws IOException If fails
+         */
+        public String single(final CharSequence name) throws IOException {
+            final Iterator<String> params = this.header(name).iterator();
+            if (!params.hasNext()) {
+                throw new HttpException(
+                    HttpURLConnection.HTTP_BAD_REQUEST,
+                    String.format(
+                        "header \"%s\" is mandatory, not found among %s",
+                        name, this.names()
+                    )
+                );
+            }
+            return params.next();
+        }
+
+        /**
+         * If header is present, returns the first header value.
+         * If not, returns a default value.
+         * @param name Name of header key
+         * @param def Default value
+         * @return Header Value or default value
+         * @throws IOException If fails
+         */
+        public String single(final CharSequence name, final CharSequence def)
+            throws IOException {
+            final String value;
+            final Iterator<String> params = this.header(name).iterator();
+            if (params.hasNext()) {
+                value = params.next();
+            } else {
+                value = def.toString();
+            }
+            return value;
+        }
+
+    }
+}

src/test/java/org/takes/rs/RsHeadersTest.java

@@ -0,0 +1,54 @@
+/*
+ * The MIT License (MIT)
+ *
+ * Copyright (c) 2014-2022 Yegor Bugayenko
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included
+ * in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+package org.takes.rs;
+
+import java.io.IOException;
+import org.hamcrest.MatcherAssert;
+import org.hamcrest.Matchers;
+import org.junit.jupiter.api.Test;
+
+/**
+ * Test case for {@link RsHeaders}.
+ * @since 0.1
+ */
+final class RsHeadersTest {
+
+    /**
+     * RsHeaders can parse headers.
+     * @throws IOException If some problem inside
+     */
+    @Test
+    void parsesHttpHeaders() throws IOException {
+        MatcherAssert.assertThat(
+            new RsHeaders.Base(
+                new RsWithHeader(
+                    new RsEmpty(),
+                    "Content-type", "text/plain"
+                )
+            ).header("content-type"),
+            Matchers.hasItem("text/plain")
+        );
+    }
+
+}