WIP: Spike - Add OR operator to cps-path

Antlr changes to be made to recognize OR as input in cps-path

Adding OR operator to the antlr grammer file 

PATH : cps-path-parser/src/main/antlr4/org/onap/cps/cpspath/parser/antlr4/CpsPath.g4

Solution : listElementRef :  OB leafCondition ( ( KW_AND | KW_OR) leafCondition)* CB 
                multipleLeafConditions : OB leafCondition ( ( KW_AND | KW_OR) leafCondition)* CB 

It is tested by antlr test

Code changes made to recognise the operatoe i.e., and ,or

PATH:cps-path-parser/src/main/java/org/onap/cps/cpspath/parser/CpsPathBuilder.java

Solution:

String parent = ctx.getParent().getText();
        String payload = ctx.getPayload().getText();
        payloads.add(payload);
        String operator = findOperator(parent, payloads);
        appendCondition(normalizedXpathBuilder, ctx.leafName().getText(), comparisonValue, operator);
        if (processingAncestorAxis) {
            appendCondition(normalizedAncestorPathBuilder, ctx.leafName().getText(), comparisonValue, operator);
        }
    }

    private String findOperator(String parent, List<String> payloads) {
        StringBuilder parentStringBuilder = new StringBuilder(parent);
        try {
            payloads.forEach(payload -> parentStringBuilder.delete(parentStringBuilder.indexOf(payload), parentStringBuilder.indexOf(payload) + payload.length()));
            parentStringBuilder.delete(0, parentStringBuilder.indexOf("[") + 1);
            return parentStringBuilder.toString().trim();
        } catch (RuntimeException e) {
            return null;
        }
    }

 private void appendCondition(final StringBuilder currentNormalizedPathBuilder, final String name,
                                 final Object value, String operator) {
        final char lastCharacter = currentNormalizedPathBuilder.charAt(currentNormalizedPathBuilder.length() - 1);
        currentNormalizedPathBuilder.append(lastCharacter == '[' ? "" : " " + operator + " ");
        currentNormalizedPathBuilder.append("@");
        currentNormalizedPathBuilder.append(name);
        currentNormalizedPathBuilder.append("='");
        currentNormalizedPathBuilder.append(value);
        currentNormalizedPathBuilder.append("'");
    }
}

PATH:cps-path-parser/src/test/groovy/org/onap/cps/cpspath/parser/CpsPathQuerySpec.groovy

1. def 'Parse cps path having OR operator containing #scenario.'() {
        when: 'the given cps path is parsed'

       def result = CpsPathUtil.getCpsPathQuery(cpsPath)
        then: 'the query has the right normalized xpath type'
        assert result.normalizedXpath == expectedNormalizedXPath
        where: 'the following data is used'
        scenario                                              | cpsPath                                         || expectedNormalizedXPath
        'parent & child with more than one attribute'         | '/parent/child[@key1=1 or @key2="abc"]/child2'  || "/parent/child[@key1='1' or @key2='abc']/child2"
    }

 2.   def 'Parse cps path that ends with a yang list containing #scenario and having or operator '() {
        when: 'the given cps path is parsed'
        def result = CpsPathQuery.createFrom(cpsPath)
        then: 'the query has the right xpath type'
        result.cpsPathPrefixType == DESCENDANT
        and: 'the right parameters are set'
        result.descendantName == "child"
        result.leavesData.size() == expectedNumberOfLeaves
        where: 'the following data is used'
        scenario                  | cpsPath                                            || expectedNumberOfLeaves
        'more than one attribute' | '//child[@int-leaf=5 or @leaf-name="leaf value"]'  || 2
    }

Testcases in 

CpsDataPersistenceQueryDataNodeSpec.groovy

@Sql([CLEAR_DATA, SET_DATA])
def 'Cps Path query using descendant anywhere with #scenario OR condition(s) for a container element.'() {
    when: 'a query is executed to get a data node by the given cps path'
    def result = objectUnderTest.queryDataNodes(DATASPACE_NAME, ANCHOR_FOR_SHOP_EXAMPLE, cpsPath, OMIT_DESCENDANTS)
    then: 'the correct number of data nodes are retrieved'
    result.size() == expectedXPaths.size()
    and: 'xpaths of the retrieved data nodes are as expected'
    for (int i = 0; i < result.size(); i++) {
        assert result[i].getXpath() == expectedXPaths[i]
    }
    where: 'the following data is used'
    scenario                   | cpsPath                                               || expectedXPaths
    'more than one leaf'       | '//author[@FirstName="Joe" or @title="title"]'        || ["/shops/shop[@id='1']/categories[@code='1']/book/author[@FirstName='Joe' or @Surname='Bloggs']"]
    'leaves has OR condition'  | '//author[@FirstName="Joe" or @Firstname="Jane"]'     || ["/shops/shop[@id=''1'']/categories[@code=''1'']/book/author[@FirstName='Joe']", "/shops/shop[@id=''1'']/categories[@code=''2'']/book/author[@FirstName=''Jane'']"]
}