Apostrophe handling in CpsPathParser

Apostrophe is not currently handled correctly, and having apostrophe in
the xpath will lead to various errors.
For example, normalizing this xpath works:
  /path[@name="I'm quoted"] -> /path[@name='I\'m quoted']
However the resulting xpath will throw a PathParsingException if parsed!
(Thus path normalization is not idempotent.)

- Use '' for escaping apostrophe in single quoted leaf value,
  to comply with XPath standard (and use "" for escaping in ").
- Use Liquibase to make existing data comply with new rules.
- Leaf values in data leaves are now unescaped, e.g. "I'm quoted"
- Quoting is now consistent for leaf/text/contains conditions.

Issue-ID: CPS-1769
Signed-off-by: danielhanrahan <daniel.hanrahan@est.tech>
Change-Id: Iafc287f738254d7f99706c6bc548091c0ecd5aa0

2 files changed, 31 insertions, 20 deletions

diff --git a/cps-path-parser/src/main/antlr4/org/onap/cps/cpspath/parser/antlr4/CpsPath.g4 b/cps-path-parser/src/main/antlr4/org/onap/cps/cpspath/parser/antlr4/CpsPath.g4
index c88a822654..3aef120fed 100644
--- a/cps-path-parser/src/main/antlr4/org/onap/cps/cpspath/parser/antlr4/CpsPath.g4
+++ b/cps-path-parser/src/main/antlr4/org/onap/cps/cpspath/parser/antlr4/CpsPath.g4
@@ -1,6 +1,6 @@
 /*
  *  ============LICENSE_START=======================================================
- *  Copyright (C) 2021-2022 Nordix Foundation
+ *  Copyright (C) 2021-2023 Nordix Foundation
  *  Modifications Copyright (C) 2023 TechMahindra Ltd
  *  ================================================================================
  *  Licensed under the Apache License, Version 2.0 (the "License");
@@ -19,6 +19,12 @@
  *  ============LICENSE_END=========================================================
  */
 
+/*
+ * Parser Rules
+ * Some of the parser rules below are inspired by
+ * https://github.com/antlr/grammars-v4/blob/master/xpath/xpath31/XPath31Parser.g4
+ */
+
 grammar CpsPath ;
 
 cpsPath : ( prefix | descendant | incorrectPrefix ) multipleLeafConditions? textFunctionCondition? containsFunctionCondition? ancestorAxis? invalidPostFix?;
@@ -60,7 +66,7 @@ invalidPostFix : (AT | CB | COLONCOLON | comparativeOperators ).+ ;
 /*
  * Lexer Rules
  * Most of the lexer rules below are inspired by
- * https://raw.githubusercontent.com/antlr/grammars-v4/master/xpath/xpath31/XPath31.g4
+ * https://github.com/antlr/grammars-v4/blob/master/xpath/xpath31/XPath31Lexer.g4
  */
 
 AT : '@' ;
@@ -89,9 +95,9 @@ IntegerLiteral : FragDigits ;
 // Add below type definitions for leafvalue comparision in https://jira.onap.org/browse/CPS-440
 DecimalLiteral : ('.' FragDigits) | (FragDigits '.' [0-9]*) ;
 DoubleLiteral : (('.' FragDigits) | (FragDigits ('.' [0-9]*)?)) [eE] [+-]? FragDigits ;
-StringLiteral : ('"' (FragEscapeQuot | ~[^"])*? '"') | ('\'' (FragEscapeApos | ~['])*? '\'') ;
+StringLiteral : '"' (~["] | FragEscapeQuot)* '"' | '\'' (~['] | FragEscapeApos)* '\'' ;
 fragment FragEscapeQuot : '""' ;
-fragment FragEscapeApos : '\'' ;
+fragment FragEscapeApos : '\'\'';
 fragment FragDigits : [0-9]+ ;
 
 QName  : FragQName ;
diff --git a/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java b/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java
index 99135962f8..de261e64b3 100644
--- a/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java
+++ b/cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java
@@ -79,18 +79,13 @@ public class CpsPathBuilder extends CpsPathBaseListener {
 
     @Override
     public void exitLeafCondition(final LeafConditionContext ctx) {
-        Object comparisonValue;
+        final Object comparisonValue;
         if (ctx.IntegerLiteral() != null) {
             comparisonValue = Integer.valueOf(ctx.IntegerLiteral().getText());
         } else if (ctx.StringLiteral() != null) {
-            final boolean wasWrappedInDoubleQuote = ctx.StringLiteral().getText().startsWith("\"");
-            comparisonValue = stripFirstAndLastCharacter(ctx.StringLiteral().getText());
-            if (wasWrappedInDoubleQuote) {
-                comparisonValue = String.valueOf(comparisonValue).replace("'", "\\'");
-            }
+            comparisonValue = unwrapQuotedString(ctx.StringLiteral().getText());
         } else {
-            throw new PathParsingException(
-                    "Unsupported comparison value encountered in expression" + ctx.getText());
+            throw new PathParsingException("Unsupported comparison value encountered in expression" + ctx.getText());
         }
         leafContext(ctx.leafName(), comparisonValue);
     }
@@ -140,13 +135,13 @@ public class CpsPathBuilder extends CpsPathBaseListener {
     @Override
     public void exitTextFunctionCondition(final TextFunctionConditionContext ctx) {
         cpsPathQuery.setTextFunctionConditionLeafName(ctx.leafName().getText());
-        cpsPathQuery.setTextFunctionConditionValue(stripFirstAndLastCharacter(ctx.StringLiteral().getText()));
+        cpsPathQuery.setTextFunctionConditionValue(unwrapQuotedString(ctx.StringLiteral().getText()));
     }
 
     @Override
     public void exitContainsFunctionCondition(final CpsPathParser.ContainsFunctionConditionContext ctx) {
         cpsPathQuery.setContainsFunctionConditionLeafName(ctx.leafName().getText());
-        cpsPathQuery.setContainsFunctionConditionValue(stripFirstAndLastCharacter(ctx.StringLiteral().getText()));
+        cpsPathQuery.setContainsFunctionConditionValue(unwrapQuotedString(ctx.StringLiteral().getText()));
     }
 
     @Override
@@ -173,10 +168,6 @@ public class CpsPathBuilder extends CpsPathBaseListener {
         return cpsPathQuery;
     }
 
-    private static String stripFirstAndLastCharacter(final String wrappedString) {
-        return wrappedString.substring(1, wrappedString.length() - 1);
-    }
-
     @Override
     public void exitContainerName(final CpsPathParser.ContainerNameContext ctx) {
         final String containerName = ctx.getText();
@@ -207,11 +198,25 @@ public class CpsPathBuilder extends CpsPathBaseListener {
                                     .append(name)
                                     .append(getLastElement(comparativeOperators))
                                     .append("'")
-                                    .append(value)
+                                    .append(value.toString().replace("'", "''"))
                                     .append("'");
     }
 
-    private String getLastElement(final List<String> listOfStrings) {
+    private static String getLastElement(final List<String> listOfStrings) {
         return listOfStrings.get(listOfStrings.size() - 1);
     }
+
+    private static String unwrapQuotedString(final String wrappedString) {
+        final boolean wasWrappedInSingleQuote = wrappedString.startsWith("'");
+        final String value = stripFirstAndLastCharacter(wrappedString);
+        if (wasWrappedInSingleQuote) {
+            return value.replace("''", "'");
+        } else {
+            return value.replace("\"\"", "\"");
+        }
+    }
+
+    private static String stripFirstAndLastCharacter(final String wrappedString) {
+        return wrappedString.substring(1, wrappedString.length() - 1);
+    }
 }