Adds ipaddr filter to test if string is valid IP Address.

src/main/java/com/hubspot/jinjava/lib/filter/FilterLibrary.java

@@ -74,6 +74,7 @@ protected void registerDefaults() {
         ReverseFilter.class,
         RoundFilter.class,
         SumFilter.class,
+        IpAddrFilter.class,
 
         EscapeFilter.class,
         EAliasedEscapeFilter.class,

src/main/java/com/hubspot/jinjava/lib/filter/IpAddrFilter.java

@@ -0,0 +1,50 @@
+package com.hubspot.jinjava.lib.filter;
+
+import java.util.regex.Pattern;
+
+import com.hubspot.jinjava.doc.annotations.JinjavaDoc;
+import com.hubspot.jinjava.doc.annotations.JinjavaParam;
+import com.hubspot.jinjava.doc.annotations.JinjavaSnippet;
+import com.hubspot.jinjava.interpret.JinjavaInterpreter;
+
+@JinjavaDoc(
+    value = "Evaluates to true if the value is a valid IPv4 or IPv6 address",
+    params = {
+        @JinjavaParam(value = "value", type = "string", desc = "String to check IP Address"),
+    },
+    snippets = {
+        @JinjavaSnippet(
+            desc = "This example shows how to test if a string is a valid ip address",
+            code = "{% set ip = '1.0.0.1' %}\n" +
+                "{% if ip|ipaddr %}\n" +
+                "    The string is a valid IP address\n" +
+                "{% endif %}")
+    })
+public class IpAddrFilter implements Filter {
+
+  private static final Pattern IP4_PATTERN = Pattern.compile("(([01]?\\d\\d?|2[0-4]\\d|25[0-5])\\.){3}([01]?\\d\\d?|2[0-4]\\d|25[0-5])");
+  private static final Pattern IP6_PATTERN = Pattern.compile("^(?:[0-9a-fA-F]{1,4}:){7}[0-9a-fA-F]{1,4}$");
+  private static final Pattern IP6_COMPRESSED_PATTERN = Pattern.compile("^((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)::((?:[0-9A-Fa-f]{1,4}(?::[0-9A-Fa-f]{1,4})*)?)$");
+
+  @Override
+  public Object filter(Object object, JinjavaInterpreter interpreter, String... arg) {
+
+    if (object == null) {
+      return false;
+    }
+
+    if (object instanceof String) {
+      String address = ((String) object).trim();
+      return IP4_PATTERN.matcher(address).matches()
+          || IP6_PATTERN.matcher(address).matches()
+          || IP6_COMPRESSED_PATTERN.matcher(address).matches();
+    }
+    return false;
+  }
+
+  @Override
+  public String getName() {
+    return "ipaddr";
+  }
+
+}

src/test/java/com/hubspot/jinjava/lib/filter/IpAddrFilterTest.java

@@ -0,0 +1,54 @@
+package com.hubspot.jinjava.lib.filter;
+
+import static org.assertj.core.api.AssertionsForClassTypes.assertThat;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import com.hubspot.jinjava.Jinjava;
+import com.hubspot.jinjava.interpret.JinjavaInterpreter;
+
+public class IpAddrFilterTest {
+
+  private IpAddrFilter ipAddrFilter;
+  private JinjavaInterpreter interpreter;
+
+  @Before
+  public void setup() {
+    ipAddrFilter = new IpAddrFilter();
+    interpreter = new Jinjava().newInterpreter();
+  }
+
+  @Test
+  public void itAcceptsValidIpV4Address() {
+    assertThat(ipAddrFilter.filter("255.182.100.1", interpreter)).isEqualTo(true);
+    assertThat(ipAddrFilter.filter("125.0.100.1", interpreter)).isEqualTo(true);
+    assertThat(ipAddrFilter.filter("128.0.0.1", interpreter)).isEqualTo(true);
+    assertThat(ipAddrFilter.filter("   128.0.0.1   ", interpreter)).isEqualTo(true);
+  }
+
+  @Test
+  public void itRejectsInvalidIpV4Address() {
+    assertThat(ipAddrFilter.filter("255.182.100.abc", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter("125.512.100.1", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter("125.512.100.1.1", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter("125.512.100", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter(104, interpreter)).isEqualTo(false);
+  }
+
+  @Test
+  public void itAcceptsValidIpV6Address() {
+    assertThat(ipAddrFilter.filter("1200:0000:AB00:1234:0000:2552:7777:1313", interpreter)).isEqualTo(true);
+    assertThat(ipAddrFilter.filter("21DA:D3:0:2F3B:2AA:FF:FE28:9C5A", interpreter)).isEqualTo(true);
+    assertThat(ipAddrFilter.filter("2000::", interpreter)).isEqualTo(true);
+  }
+
+  @Test
+  public void itRejectsInvalidIpV6Address() {
+    assertThat(ipAddrFilter.filter("1200::AB00:1234::2552:7777:1313", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter("1200:0000:AB00:1234:O000:2552:7777:1313", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter("1200::AB00:1234::2552:7777:1313:1232", interpreter)).isEqualTo(false);
+    assertThat(ipAddrFilter.filter("321", interpreter)).isEqualTo(false);
+  }
+
+}