add methods to generate random port within given range (#1651)

Author: asolntsev

src/main/java/net/datafaker/providers/base/Internet.java

@@ -21,12 +21,13 @@
 public class Internet extends AbstractProvider<BaseProviders> {
     private static final Pattern COLON = Pattern.compile(":");
     private static final List<String> HTTP_SCHEMES = List.of("http://", "https://");
+    private static final int MIN_PORT_NUMBER = 0;
+    private static final int MAX_PORT_NUMBER = 65535;
 
     protected Internet(BaseProviders faker) {
         super(faker);
     }
 
-
     /**
      * A lowercase username composed of the first_name and last_name joined with a '.'. Some examples are:
      * <ul>
@@ -128,11 +129,11 @@ private String stripAccents(String input) {
     /**
      * Converts a name to a local part (the part before the '@') of an email
      * address.
-     * 
+     *
      * Will use the first and last names of the provided name, ignoring middle
      * names, and will remove any prefixes or suffixes that are defined in the
      * faker's configuration.
-     * 
+     *
      * @param name The name ({@link Name}) to be converted to a local part.
      * @return A String representing the local part of an email address.
      * @since 2.4.5
@@ -211,7 +212,7 @@ public String url() {
      * @since 2.0.0
      */
     public String url(boolean schemeChoice, boolean portChoice, boolean pathChoice, boolean fileChoice, boolean paramsChoice, boolean anchorChoice) {
-        String scheme = schemeChoice ? HTTP_SCHEMES.get(faker.random().nextInt(0, 1)) : "https://";
+        String scheme = schemeChoice ? faker.options().nextElement(HTTP_SCHEMES) : "https://";
         String port = portChoice ? (":" + port()) : "";
         String path = pathChoice ? ("/" + slug(faker.lorem().words(2), "/")) : "/";
         String file = fileChoice ? faker.lorem().words(1).get(0) : "";
@@ -314,7 +315,32 @@ public String password(int minimumLength, int maximumLength, boolean includeUppe
      * @return a port number
      */
     public int port() {
-        return faker.random().nextInt(0, 65535);
+        return port(MIN_PORT_NUMBER, MAX_PORT_NUMBER);
+    }
+
+    /**
+     * Returns a port number within given range
+     *
+     * @param range either Well-Known Ports (0-1023), Registered Ports (1024-49151) or Dynamic/Private Ports (49152-65535)
+     * @return a port number
+     */
+    public int port(PortRange range) {
+        return port(range.from, range.to);
+    }
+
+    /**
+     * Returns a port number between {@code from} and {@code to} (inclusive)
+     *
+     * @param from minimum port number (must not be less than 0)
+     * @param to maximum port number (must not be greater than 65535)
+     * @return a port number within given range
+     */
+    public int port(int from, int to) {
+        if (from < MIN_PORT_NUMBER)
+            throw new IllegalArgumentException("Port number %s cannot be less than %s".formatted(from, MIN_PORT_NUMBER));
+        if (to > MAX_PORT_NUMBER)
+            throw new IllegalArgumentException("Port number %s cannot be greater than %s".formatted(to, MAX_PORT_NUMBER));
+        return faker.random().nextInt(from, to);
     }
 
     /**
@@ -653,4 +679,18 @@ private static InetAddress inet6Address(String host) {
             throw new RuntimeException("Failed to create Inet6Address from host '%s'".formatted(host), e);
         }
     }
+
+    public enum PortRange {
+        WellKnownPorts(0, 1023),
+        RegisteredPorts(1024, 49151),
+        DynamicPrivatePorts(49152, 65535);
+
+        private final int from;
+        private final int to;
+
+        PortRange(int from, int to) {
+            this.from = from;
+            this.to = to;
+        }
+    }
 }

src/test/java/net/datafaker/providers/base/InternetTest.java

@@ -1,8 +1,8 @@
 package net.datafaker.providers.base;
 
 import net.datafaker.Faker;
+import net.datafaker.providers.base.Internet.PortRange;
 import net.datafaker.service.FakeValuesService;
-
 import org.apache.commons.validator.routines.EmailValidator;
 import org.assertj.core.api.Condition;
 import org.junit.jupiter.api.RepeatedTest;
@@ -18,8 +18,11 @@
 import java.util.stream.Collectors;
 
 import static java.lang.Integer.parseInt;
+import static net.datafaker.providers.base.Internet.PortRange.RegisteredPorts;
+import static net.datafaker.providers.base.Internet.PortRange.WellKnownPorts;
 import static org.assertj.core.api.Assertions.anyOf;
 import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatThrownBy;
 import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
 import static org.mockito.Mockito.doReturn;
 import static org.mockito.Mockito.mock;
@@ -31,7 +34,7 @@ class InternetTest {
     public static final Pattern IPV6_HOST_ADDRESS = Pattern.compile("[0-9a-fA-F]{1,4}(:([0-9a-fA-F]{1,4})){1,7}");
     private final Faker faker = new Faker();
 
-    @RepeatedTest(100)
+    @RepeatedTest(10)
     @SuppressWarnings("removal")
     void testUsername() {
         assertThat(faker.internet().username()).matches("^(\\w+)\\.(\\w+)$");
@@ -182,7 +185,7 @@ void testWebdomain() {
         assertThat(faker.internet().webdomain()).matches("www\\.[\\w-]+\\.\\w+");
     }
 
-    @RepeatedTest(100)
+    @RepeatedTest(10)
     void testUrl() {
         // This test assumes that java.net.URL has better validation than we can come up with in
         // regex.
@@ -263,11 +266,41 @@ void testPasswordMinLengthMaxLengthIncludeUpperCaseIncludeSpecial() {
         assertThat(faker.internet().password(10, 25, true, true)).matches("[a-zA-Z\\d!@#$%^&*]{10,25}");
     }
 
-    @RepeatedTest(100)
+    @RepeatedTest(10)
     void testPort() {
         assertThat(faker.internet().port()).isBetween(0, 65535);
     }
 
+    @RepeatedTest(10)
+    void portWithinGivenBounds() {
+        assertThat(faker.internet().port(0, 1)).isBetween(0, 1);
+        assertThat(faker.internet().port(100, 200)).isBetween(100, 200);
+        assertThat(faker.internet().port(1000, 1000)).isEqualTo(1000);
+        assertThat(faker.internet().port(65535, 65535)).isEqualTo(65535);
+    }
+
+    @RepeatedTest(10)
+    void portWithinGivenRange() {
+        assertThat(faker.internet().port(WellKnownPorts)).isBetween(0, 1023);
+        assertThat(faker.internet().port(RegisteredPorts)).isBetween(1024, 49151);
+        assertThat(faker.internet().port(PortRange.DynamicPrivatePorts)).isBetween(49152, 65535);
+    }
+
+    @Test
+    void portWithinGivenRange_validation() {
+        assertThatThrownBy(() -> faker.internet().port(-1, 100))
+            .isInstanceOf(IllegalArgumentException.class)
+            .hasMessage("Port number -1 cannot be less than 0");
+
+        assertThatThrownBy(() -> faker.internet().port(100, 99))
+            .isInstanceOf(IllegalArgumentException.class)
+            .hasMessage("Min (100) > Max (99)");
+
+        assertThatThrownBy(() -> faker.internet().port(65535, 65536))
+            .isInstanceOf(IllegalArgumentException.class)
+            .hasMessage("Port number 65536 cannot be greater than 65535");
+    }
+
     @Test
     @SuppressWarnings("removal")
     void shouldGenerateAPasswordWithMinAndMaxLength() {
@@ -463,7 +496,7 @@ void testUuidv7() {
         assertThat(faker.internet().uuidv7()).matches("^[0-9a-f]{8}-[0-9a-f]{4}-7[0-9a-f]{3}-[0-9a-f]{4}-[0-9a-f]{12}$");
     }
 
-    @RepeatedTest(100)
+    @RepeatedTest(10)
     void testFarsiIDNs() {
         // in this case, we're just making sure Farsi doesn't blow up.
         // there have been issues with Farsi not being produced.