Refinement and implementation of DSL ruleset specifications

Author: stijn-dejongh

dsl/pom.xml

@@ -25,6 +25,12 @@
   </properties>
 
   <dependencies>
+    <dependency>
+      <groupId>com.opencsv</groupId>
+      <artifactId>opencsv</artifactId>
+      <version>5.9</version>
+    </dependency>
+
     <dependency>
       <groupId>be.sddevelopment.validation</groupId>
       <artifactId>core</artifactId>
@@ -69,6 +75,11 @@
       <artifactId>archunit</artifactId>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-params</artifactId>
+      <scope>test</scope>
+    </dependency>
     <dependency>
       <groupId>com.tngtech.archunit</groupId>
       <artifactId>archunit-junit5</artifactId>

dsl/src/main/java/be/sddevelopment/validation/dsl/CsvFile.java

@@ -0,0 +1,29 @@
+package be.sddevelopment.validation.dsl;
+
+import java.nio.file.Path;
+import java.util.Vector;
+import java.util.stream.Stream;
+
+public record CsvFile (
+    String fileIdentifier,
+    Vector<String> headerFields,
+    Vector<Vector<String>> lines
+) {
+    public CsvFile {
+        if (headerFields == null || lines == null) {
+            throw new IllegalArgumentException("Header fields and lines must not be null");
+        }
+    }
+
+    public Vector<String> line(int lineNumber) {
+        return lines.get(lineNumber);
+    }
+
+    public static CsvFile fromLines(Stream<String> lines) {
+        return null;
+    }
+
+    public static CsvFile fromFile(Path dataFile) {
+        return null;
+    }
+}

dsl/src/main/java/be/sddevelopment/validation/dsl/FileValidatorParser.java

@@ -0,0 +1,52 @@
+package be.sddevelopment.validation.dsl;
+
+import be.sddevelopment.commons.annotations.Utility;
+import be.sddevelopment.validation.core.ModularRuleset;
+import be.sddevelopment.validation.core.ModularRuleset.ModularValidatorBuilder;
+import org.apache.commons.lang3.StringUtils;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+import java.util.List;
+import java.util.function.Function;
+
+import static be.sddevelopment.commons.access.AccessProtectionUtils.utilityClassConstructor;
+
+@Utility
+public final class FileValidatorParser {
+
+    private FileValidatorParser() {
+        utilityClassConstructor();
+    }
+
+    public static ModularRuleset<CsvFile> fromSpecification(Path validationSpec) throws SpecificationParserException {
+        try {
+            var lines = Files.readAllLines(validationSpec);
+            var ruleSet = ModularRuleset.aValid(CsvFile.class);
+            lines.stream()
+                    .filter(StringUtils::isNotBlank)
+                    .filter(FileValidatorParser::isRuleSpecification)
+                    .map(FileValidatorParser::<CsvFile>toRuleAdder)
+                    .forEach(ruleAdder -> ruleAdder.apply(ruleSet));
+            return ruleSet.iHaveSpoken();
+        } catch (IOException e) {
+            throw new SpecificationParserException("Error processing validation specification file", e);
+        }
+    }
+
+    private static final List<String> KNOWN_RULESPECS = List.of(
+            "RecordIdentifier",
+            "FieldExists",
+            "FieldPopulated",
+            "RecordExists"
+    );
+
+    static boolean isRuleSpecification(String specificationLine) {
+        return KNOWN_RULESPECS.stream().anyMatch(specificationLine::contains);
+    }
+
+    static <T> Function<ModularValidatorBuilder<T>, ModularValidatorBuilder<T>> toRuleAdder(String line) {
+        return ruleset -> ruleset;
+    }
+}

dsl/src/main/java/be/sddevelopment/validation/dsl/SpecificationParserException.java

@@ -0,0 +1,18 @@
+package be.sddevelopment.validation.dsl;
+
+/**
+ * Exception thrown when an error occurs while parsing a validation specification.
+ * To be used by the {@link FileValidatorParser} or related specification file to {@link be.sddevelopment.validation.core.ModularRuleset} parsers.
+ *
+ * @since 1.1.0
+ */
+public class SpecificationParserException extends Exception {
+
+    public SpecificationParserException(String message) {
+        super(message);
+    }
+
+    public SpecificationParserException(String message, Throwable cause) {
+        super(message, cause);
+    }
+}

dsl/src/main/java/be/sddevelopment/validation/dsl/ValidatorParser.java

@@ -1,7 +1,7 @@
 /**
  * <p>
  * Contains the domain-specific language classes (DSL) for the validation framework. These classes are used to create the validation rules, based on the DSL specifications provided to it.
- * The most notable entries are {@link be.sddevelopment.validation.dsl.ValidatorParser}.
+ * The most notable entries are {@link be.sddevelopment.validation.dsl.FileValidatorParser}.
  * </p>
  *
  * @since 1.1.0-SNAPSHOT

dsl/src/main/java/be/sddevelopment/validation/dsl/package-info.java

@@ -0,0 +1,31 @@
+package be.sddevelopment.validation.dsl;
+
+import be.sddevelopment.commons.testing.naming.ReplaceUnderscoredCamelCasing;
+import org.assertj.core.api.WithAssertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.DisplayNameGeneration;
+import org.junit.jupiter.api.Test;
+
+@DisplayName("Comma Separated Values File")
+@DisplayNameGeneration(ReplaceUnderscoredCamelCasing.class)
+class CsvFileTest implements WithAssertions {
+
+    @Test
+    void canBeCreatedFromLines() {
+        var dataWithHeader = """
+            NAME,HEIGHT,SPECIES
+            Luke Skywalker,172,Human
+            C-3PO,167,Droid
+            R2-D2,96,Droid
+            Boba Fett,183, Human
+        """;
+
+        var csvFile = CsvFile.fromLines(dataWithHeader.lines());
+
+        assertThat(csvFile).isNotNull()
+                .extracting(CsvFile::headerFields)
+                .asInstanceOf(LIST)
+                .containsExactly("NAME", "HEIGHT", "SPECIES");
+        assertThat(csvFile.line(0)).containsExactly("Luke Skywalker", "172", "Human");
+    }
+}

dsl/src/test/java/be/sddevelopment/validation/dsl/CsvFileTest.java

@@ -0,0 +1,78 @@
+package be.sddevelopment.validation.dsl;
+
+import be.sddevelopment.commons.testing.naming.ReplaceUnderscoredCamelCasing;
+import be.sddevelopment.validation.core.ModularRuleset;
+import be.sddevelopment.validation.core.Rationale;
+import com.opencsv.CSVParser;
+import com.opencsv.bean.util.OpencsvUtils;
+import org.assertj.core.api.WithAssertions;
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.DisplayNameGeneration;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.ValueSource;
+
+import java.io.IOException;
+import java.nio.file.Paths;
+
+@DisplayName("Parsing of validation rules")
+@DisplayNameGeneration(ReplaceUnderscoredCamelCasing.class)
+class FileValidatorParserTest implements WithAssertions {
+
+    @Test
+    void createsAValidatorBasedOnSpecifications() throws IOException, SpecificationParserException {
+        var validationSpec = Paths.get("src/test/resources/parsing/star_wars/STARWARS_VALIDATOR.puml");
+        var dataFile = Paths.get("src/test/resources/parsing/star_wars/STARWARS_INPUT_DATA.csv");
+        assertThat(validationSpec).exists();
+        assertThat(validationSpec).isRegularFile();
+
+        var validator = FileValidatorParser.fromSpecification(validationSpec);
+        assertThat(validator).isNotNull();
+
+        var result = validator.check(CsvFile.fromFile(dataFile));
+
+        assertThat(result).isNotNull()
+                .matches(Rationale::isPassing);
+    }
+
+    @Nested
+    class parsesSimplesRulesTest {
+
+        @ParameterizedTest
+        @ValueSource(strings = {
+                "RecordIdentifier('NAME')",
+                "FieldPopulated('SPECIES')",
+                "FieldExists('HOMEWORLD')",
+                "RecordExists('C-3PO')"
+        })
+        void recognizesSimpleRule(String ruleToParse) {
+            assertThat(ruleToParse).matches(
+                    FileValidatorParser::isRuleSpecification,
+                    "is recognized as a rule specification"
+            );
+        }
+
+        @Test
+        void canCheckFieldExistence() {
+            var dataFile = CsvFile.fromLines(
+                    """
+                    NAME,HEIGHT,SPECIES
+                    Luke Skywalker,172,Human
+                    C-3PO,167,Droid
+                    R2-D2,96,Droid
+                    Boba Fett,183, Human
+                    """.lines()
+            );
+            var rule = "FieldExists('HOMEWORLD')";
+            var ruleAdder = FileValidatorParser.<CsvFile>toRuleAdder(rule);
+
+            var ruleset = ModularRuleset.aValid(CsvFile.class);
+            ruleAdder.apply(ruleset);
+
+            var result = ruleset.iHaveSpoken().check(dataFile);
+
+            assertThat(result).isNotNull().matches(Rationale::isFailing, "fails because the field does not exist");
+        }
+    }
+}

dsl/src/test/java/be/sddevelopment/validation/dsl/FileValidatorParserTest.java

@@ -1,5 +1,5 @@
 ValidatorFor(".*STARWARS.*\\.csv") {
-	Header{
+	Header {
 		Field('NAME')
 		Field('HEIGHT')
 		Field('MASS')
@@ -11,6 +11,7 @@ ValidatorFor(".*STARWARS.*\\.csv") {
 		Field('HOMEWORLD')
 		Field('SPECIES')
 	}
+
 	RecordIdentifier('NAME')
 	FieldPopulated('SPECIES')
 	FieldPopulated('HOMEWORLD')