Added formatCreditCard

.github/workflows/publish.yml

@@ -1,6 +1,7 @@
 name: Publish to the Maven Central
 
 on:
+  workflow_dispatch:
   release:
     types: [released]
 

.idea/misc.xml

@@ -44,6 +44,9 @@
     <pattern value="rife.render.TestDateTime" method="testTimeIso" />
     <pattern value="rife.render.TestDateTime" method="testYear" />
     <pattern value="rife.render.ValueBean" />
+    <pattern value="rife.render.RenderUtils" method="formatCreditCard" />
+    <pattern value="rife.render.RenderUtils" />
+    <pattern value="rife.render.RenderUtils" method="RenderUtils" />
   </component>
   <component name="ExternalStorageConfigurationManager" enabled="true" />
   <component name="PDMPlugin">

README.md

@@ -22,7 +22,7 @@ This project provides a collection of template renderers.
 ## Encoding Renderers
 
 | Renderer                         | Description                                            |
-|:---------------------------------|:--------------------------------------------------------|
+|:---------------------------------|:-------------------------------------------------------|
 | `rife.render.EncodeBase64`       | Encodes a template value to Base64                     |
 | `rife.render.EncodeHtml`         | Encodes a template value to HTML                       |
 | `rife.render.EncodeHtmlEntities` | Encodes a template value to HTML decimal entities      |
@@ -32,7 +32,13 @@ This project provides a collection of template renderers.
 | `rife.render.EncodeUnicode`      | Encodes a template value to Unicode escape codes       |
 | `rife.render.EncodeUrl`          | URL-encodes a template value                           |
 | `rife.render.EncodeXml`          | Encodes a template value to XML                        |
-| `rife.render.ShorteUrl`          | Shortens a template value using [is.gd](https://is.gd/) |
+
+## Format Renderers
+
+| Renderer                         | Description                                                      |
+|:---------------------------------|:-----------------------------------------------------------------|
+| `rife.render.formatCreditcard`   | Formats a template credit card number value to the last 4 digits |
+| `rife.render.ShorteUrl`          | Shortens a template value using [is./gd](https://is.gd/)         |
 
 
 ## Text Renderers

lib/build.gradle.kts

@@ -73,7 +73,7 @@ tasks {
             this as StandardJavadocDocletOptions
             keyWords(true)
             splitIndex(true)
-            links()
+            links("https://rife2.github.io/rife2/")
         }
     }
 }

lib/src/main/java/rife/render/FormatCreditCard.java

@@ -0,0 +1,44 @@
+/*
+ *  Copyright 2023 the original author or authors.
+ *
+ *  Licensed 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
+ *
+ *       https://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 rife.render;
+
+import rife.template.Template;
+import rife.template.ValueRenderer;
+
+/**
+ * Formats a template credit card number value to the last 4 digits.
+ *
+ * <p>Usage:</p>
+ *
+ * <pre>
+ *   &lt;!--v render:rife.render.FormatCreditCard:valueId/--&gt;
+ *   {{v render:rife.render.FormatCreditCard:valueId/}}
+ * </pre>
+ *
+ * @author <a href="https://erik.thauvin.net/">Erik C. Thauvin</a>
+ * @since 1.0
+ */
+public class FormatCreditCard implements ValueRenderer {
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    public String render(Template template, String valueId, String differentiator) {
+        return RenderUtils.formatCreditCard(RenderUtils.fetchValue(template, differentiator));
+    }
+}

lib/src/main/java/rife/render/RenderUtils.java

@@ -53,7 +53,7 @@ public final class RenderUtils {
     /**
      * Encodes a string to JavaScript/ECMAScript.
      *
-     * @param src the source string.
+     * @param src the source string
      * @return the enocded string
      */
     public static String encodeJS(String src) {
@@ -96,11 +96,53 @@ public final class RenderUtils {
         return Convert.toString(value);
     }
 
+    /**
+     * Returns the last 4 digits a credit card number. The number must satisfy the Luhn algorithm.
+     * Non-digits are stripped from the number.
+     *
+     * @param src the credit card number
+     * @return the last 4 digits of the credit card number or empty
+     */
+    public static String formatCreditCard(String src) {
+        if (src == null || src.isBlank()) {
+            return src;
+        }
+
+        try {
+            var cc = src.replaceAll("[^0-9]", "");
+
+            var len = cc.length();
+            if (len >= 4) {
+                // Luhn algorithm
+                var sum = 0;
+                boolean isSecond = false;
+                int digit;
+                for (int i = len - 1; i >= 0; i--) {
+                    digit = cc.charAt(i) - '0';
+                    if (isSecond) {
+                        digit = digit * 2;
+                    }
+                    sum += digit / 10;
+                    sum += digit % 10;
+
+                    isSecond = !isSecond;
+                }
+                if (sum % 10 == 0) {
+                    return cc.substring(len - 4);
+                }
+            }
+        } catch (NumberFormatException ignore) {
+            // do nothing
+        }
+
+        return "";
+    }
+
     /**
      * Translates a String to/from ROT13.
      *
-     * @param src the source String.
-     * @return the translated String.
+     * @param src the source String
+     * @return the translated String
      */
     public static String rot13(String src) {
         if (src == null || src.isBlank()) {
@@ -144,7 +186,7 @@ public final class RenderUtils {
      * @return the short URL
      */
     public static String shortenUrl(String url) {
-        if (url == null || url.isBlank() || !url.matches("^[Hh][Tt][Tt][Pp][Ss]?:\\/\\/\\w.*")) {
+        if (url == null || url.isBlank() || !url.matches("^[Hh][Tt][Tt][Pp][Ss]?://\\w.*")) {
             return url;
         }
 
@@ -203,8 +245,8 @@ public final class RenderUtils {
     /**
      * Converts a text string to HTML decimal entities.
      *
-     * @param src the String to convert.
-     * @return the converted string.
+     * @param src the String to convert
+     * @return the converted String
      */
     @SuppressWarnings("PMD.AvoidReassigningLoopVariables")
     public static String toHtmlEntities(String src) {

lib/src/main/java/rife/render/ShortenUrl.java

@@ -19,7 +19,6 @@ package rife.render;
 
 import rife.template.Template;
 import rife.template.ValueRenderer;
-import rife.tools.StringUtils;
 
 /**
  * <p>Shortens a template value using <a href="https://is.gd/">is.gid</a>. The value must a valid http or https URL.</p>
@@ -34,7 +33,7 @@ import rife.tools.StringUtils;
  * </pre>
  *
  * @author <a href="https://erik.thauvin.net/">Erik C. Thauvin</a>
-= * @since 1.0
+ * @since 1.0
  */
 public class ShortenUrl implements ValueRenderer {
     /**

lib/src/test/java/rife/render/TestEncode.java

@@ -100,16 +100,4 @@ class TestEncode {
         t.setAttribute(TestCase.FOO, "a test &");
         assertThat(t.getContent()).isEqualTo("<test>\n    <foo>a test &amp;</foo>\n</test>");
     }
-
-    @Test
-    void testShortenUrl() {
-        var t = TemplateFactory.HTML.get("shortenUrl");
-        var url = "https://example.com/";
-        var shortUrl = "https://is.gd/AG3Hwv";
-        t.setValue(TestCase.FOO, url);
-        assertThat(t.getContent()).isEqualTo(String.format("<a href=\"%s\">%s</a>", shortUrl, url));
-        t.setValue(TestCase.FOO, TestCase.FOO);
-        assertThat(t.getContent()).isEqualTo("<a href=\"foo\">foo</a>");
-
-    }
 }

lib/src/test/java/rife/render/TestFormat.java

@@ -0,0 +1,50 @@
+/*
+ *  Copyright 2023 the original author or authors.
+ *
+ *  Licensed 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
+ *
+ *       https://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 rife.render;
+
+import org.junit.jupiter.api.Test;
+import rife.template.TemplateFactory;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class TestFormat {
+    @Test
+    void testFormatCreditCard() {
+        var t = TemplateFactory.TXT.get("formatCreditCard");
+        t.setAttribute(TestCase.FOO, "4342 2565 6244 0179");
+        assertThat(t.getContent()).as("US VISA").isEqualTo("0179");
+        t.setAttribute(TestCase.FOO, "5130-3899-9169-8324");
+        assertThat(t.getContent()).as("FR MASTERCARD").isEqualTo("8324");
+        t.setAttribute(TestCase.FOO, "374380141731053");
+        assertThat(t.getContent()).as("UK AMEX").isEqualTo("1053");
+        t.setAttribute(TestCase.FOO, "000000000000001");
+        assertThat(t.getContent()).isEmpty();
+    }
+
+    @Test
+    void testShortenUrl() {
+        var t = TemplateFactory.HTML.get("shortenUrl");
+        var url = "https://example.com/";
+        var shortUrl = "https://is.gd/AG3Hwv";
+        t.setValue(TestCase.FOO, url);
+        assertThat(t.getContent()).isEqualTo(String.format("<a href=\"%s\">%s</a>", shortUrl, url));
+        t.setValue(TestCase.FOO, TestCase.FOO);
+        assertThat(t.getContent()).isEqualTo("<a href=\"foo\">foo</a>");
+
+    }
+}

lib/src/test/resources/templates/formatCreditCard.txt

@@ -0,0 +1 @@
+{{v render:rife.render.FormatCreditCard:foo/}}