Merge pull request #469 from lankavitharana/addXsltParamSupport

Add parameter passing support for xslt transformations
ballerina-platform · May 14, 2024 · fe7bb90 · fe7bb90
2 parents 340fcbd + 69bd69d
commit fe7bb90
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Showing 7 changed files with 108 additions and 6 deletions.
diff --git a/ballerina/Ballerina.toml b/ballerina/Ballerina.toml
@@ -1,7 +1,7 @@
 [package]
 org = "ballerina"
 name = "xslt"
-version = "2.6.0"
+version = "2.6.1"
 authors = ["Ballerina"]
 keywords = ["xslt", "xml", "html", "xsl", "transformation"]
 repository = "https://github.com/ballerina-platform/module-ballerina-xslt"
@@ -15,8 +15,8 @@ graalvmCompatible = true
 [[platform.java17.dependency]]
 groupId = "io.ballerina.stdlib"
 artifactId = "xslt-native"
-version = "2.6.0"
-path = "../native/build/libs/xslt-native-2.6.0.jar"
+version = "2.6.1"
+path = "../native/build/libs/xslt-native-2.6.1-SNAPSHOT.jar"
 
 [[platform.java17.dependency]]
 path = "./lib/jakarta.activation-1.2.2.jar"

diff --git a/ballerina/Dependencies.toml b/ballerina/Dependencies.toml
@@ -62,7 +62,7 @@ modules = [
 [[package]]
 org = "ballerina"
 name = "xslt"
-version = "2.6.0"
+version = "2.6.1"
 dependencies = [
 	{org = "ballerina", name = "io"},
 	{org = "ballerina", name = "jballerina.java"},

diff --git a/ballerina/natives.bal b/ballerina/natives.bal
@@ -23,8 +23,9 @@ import ballerina/jballerina.java;
 #
 # + input - An XML object, which needs to be transformed
 # + xsl - The XSL style sheet represented in an XML object
+# + params - Optional parameters passed into the xslt template
 # + return - The transformed result represented in an XML object or else an `error` if the given `XML` object
 #            cannot be transformed
-public isolated function transform(xml input, xml xsl) returns xml|error = @java:Method {
+public isolated function transform(xml input, xml xsl, map<string|decimal> params = {}) returns xml|error = @java:Method {
     'class: "io.ballerina.stdlib.xslt.XsltTransformer"
 } external;
diff --git a/ballerina/tests/read-from-file.bal b/ballerina/tests/read-from-file.bal
@@ -34,6 +34,24 @@ function testReadFromFile() {
     }
 }
 
+@test:Config {}
+function testReadFromFileWithParams() returns error? {
+    string xmlFilePath = "tests/resources/datafiles/cd_catalog.xml";
+    string xslFilePath = "tests/resources/datafiles/cd_catalog_with_params.xsl";
+    string strParam = "Music CD Collection With Artist";
+    decimal intParam = 5;
+    map<string|decimal> params = {"param1":strParam, "param2": intParam};
+    xml result = check readFromFileWithParams(xmlFilePath, xslFilePath, params);
+    xml expected = check readXml("tests/resources/datafiles/read_from_file_with_params_result.xml");
+    test:assertEquals(result, expected);
+}
+
+function readFromFileWithParams(string xmlFilePath, string xslFilePath, map<string|decimal> params) returns xml|error {
+    xml xmlValue = check readXml(xmlFilePath);
+    xml xslValue = check readXml(xslFilePath);
+    return transform(xmlValue, xslValue, params);
+}
+
 @test:Config {
     enable: false
 }

diff --git a/ballerina/tests/resources/datafiles/cd_catalog_with_params.xsl b/ballerina/tests/resources/datafiles/cd_catalog_with_params.xsl
@@ -0,0 +1,27 @@
+<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
+    <xsl:param name="param1"></xsl:param>
+    <xsl:param name="param2"></xsl:param>
+    <xsl:template match="/">
+        <html>
+            <body>
+                <h2>My CD Collection</h2>
+                <h3>
+                    <xsl:value-of select="$param1"/>
+                </h3>
+                <h4>My Rating - <xsl:value-of select="$param2"/></h4>
+                <table border="1">
+                    <tr bgcolor="#9acd32">
+                        <th style="text-align:left">Title</th>
+                        <th style="text-align:left">Artist</th>
+                    </tr>
+                    <xsl:for-each select="catalog/cd">
+                        <tr>
+                            <td><xsl:value-of select="title"/></td>
+                            <td><xsl:value-of select="artist"/></td>
+                        </tr>
+                    </xsl:for-each>
+                </table>
+            </body>
+        </html>
+    </xsl:template>
+</xsl:stylesheet>
diff --git a/ballerina/tests/resources/datafiles/read_from_file_with_params_result.xml b/ballerina/tests/resources/datafiles/read_from_file_with_params_result.xml
@@ -0,0 +1,29 @@
+<html>
+   <body>
+      <h2>My CD Collection</h2>
+      <h3>Music CD Collection With Artist</h3>
+      <h4>My Rating - 5</h4>
+      <table border="1">
+         <tr bgcolor="#9acd32">
+            <th style="text-align:left">Title</th>
+            <th style="text-align:left">Artist</th>
+         </tr>
+         <tr>
+            <td>Empire Burlesque</td>
+            <td>Bob Dylan</td>
+         </tr>
+         <tr>
+            <td>Hide your heart</td>
+            <td>Bonnie Tyler</td>
+         </tr>
+         <tr>
+            <td>Greatest Hits</td>
+            <td>Dolly Parton</td>
+         </tr>
+         <tr>
+            <td>Still got the blues</td>
+            <td>Gary Moore</td>
+         </tr>
+      </table>
+   </body>
+</html>
diff --git a/native/src/main/java/io/ballerina/stdlib/xslt/XsltTransformer.java b/native/src/main/java/io/ballerina/stdlib/xslt/XsltTransformer.java
@@ -23,7 +23,11 @@
 import io.ballerina.runtime.api.types.XmlNodeType;
 import io.ballerina.runtime.api.utils.StringUtils;
 import io.ballerina.runtime.api.utils.XmlUtils;
+import io.ballerina.runtime.api.values.BArray;
 import io.ballerina.runtime.api.values.BError;
+import io.ballerina.runtime.api.values.BIterator;
+import io.ballerina.runtime.api.values.BMap;
+import io.ballerina.runtime.api.values.BString;
 import io.ballerina.runtime.api.values.BXml;
 import io.ballerina.runtime.api.values.BXmlItem;
 import io.ballerina.runtime.api.values.BXmlSequence;
@@ -56,7 +60,7 @@ public class XsltTransformer {
     private static final PrintStream errStream = System.err;
     private static final String OPERATION = "Failed to perform XSL transformation: ";
 
-    public static Object transform(BXml xmlInput, BXml xslInput) {
+    public static Object transform(BXml xmlInput, BXml xslInput, BMap<BString, Object> paramInput) {
 
         try {
             boolean unwrap = false;
@@ -83,6 +87,7 @@ public static Object transform(BXml xmlInput, BXml xslInput) {
 
             Transformer transformer = new BasicTransformerFactory().newInstance().newTransformer(xslSource);
             transformer.setOutputProperty("omit-xml-declaration", "yes");
+            applyParameters(transformer, paramInput);
             transformer.transform(xmlSource, streamResult);
 
             String resultStr = stringWriter.getBuffer().toString().trim();
@@ -104,6 +109,28 @@ public static Object transform(BXml xmlInput, BXml xslInput) {
         }
     }
 
+    /**
+     * Apply template parameters to the transformer.
+     *
+     * @param transformer The transformer to be used
+     * @param paramInput The input parameter map
+     */
+    private static void applyParameters(Transformer transformer, BMap<BString, Object> paramInput) {
+        BIterator<?> iterator = paramInput.getIterator();
+        while (iterator.hasNext()) {
+            BArray next = (BArray) iterator.next();
+            BString key = (BString) next.get(0);
+            Object value = next.get(1);
+            // Note that you can add any value as long as toString method of that value works properly,
+            // Only support string and int at the moment, may be able to improve the logic to support
+            // xml as well, but current XmlItem ballerina runtime value toString method does not return
+            // the value expected by the transformer, so not supporting that at the moment
+            // And here, no need to check the types of the values as the compiler will make sure
+            // only viable types of values will arrive here
+            transformer.setParameter(key.getValue(), value);
+        }
+    }
+
     /**
      * Converts the given string to a BXmlSequence object.
      *