[ONOS-3878, 3876, 3879] Yang Parser Manager with Stack and Error Validation
Change-Id: I10e68bd676eca4d576de1234fbb67026c7b49939
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java
new file mode 100644
index 0000000..0878191
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManager.java
@@ -0,0 +1,110 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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
+ *
+ * http://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 org.onosproject.yangutils.parser.impl;
+
+import org.antlr.v4.runtime.ANTLRFileStream;
+import org.antlr.v4.runtime.ANTLRInputStream;
+import org.antlr.v4.runtime.CommonTokenStream;
+import org.antlr.v4.runtime.tree.ParseTree;
+import org.antlr.v4.runtime.tree.ParseTreeWalker;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.parser.YangUtilsParser;
+import org.onosproject.yangutils.parser.antlrgencode.GeneratedYangLexer;
+import org.onosproject.yangutils.parser.antlrgencode.GeneratedYangParser;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.parserutils.ParseTreeErrorListener;
+
+import java.io.IOException;
+
+/**
+ * Manages file parsing, parse tree creation and data model tree creation
+ * corresponding to an input YANG file.
+ */
+public class YangUtilsParserManager implements YangUtilsParser {
+
+ @Override
+ public YangNode getDataModel(String yangFile) throws IOException, ParserException {
+
+ /**
+ * Create a char stream that reads from YANG file. Throws an exception
+ * in case input YANG file is either null or non existent.
+ */
+ ANTLRInputStream input = null;
+ try {
+ input = new ANTLRFileStream(yangFile);
+ } catch (IOException e) {
+ e.printStackTrace();
+ throw e;
+ }
+
+ // Create a lexer that feeds off of input char stream.
+ GeneratedYangLexer lexer = new GeneratedYangLexer(input);
+
+ // Create a buffer of tokens pulled from the lexer.
+ CommonTokenStream tokens = new CommonTokenStream(lexer);
+
+ // Create a parser that feeds off the tokens buffer.
+ GeneratedYangParser parser = new GeneratedYangParser(tokens);
+
+ // Remove console error listener.
+ parser.removeErrorListeners();
+
+ // Create instance of customized error listener.
+ ParseTreeErrorListener parseTreeErrorListener = new ParseTreeErrorListener();
+
+ // Add customized error listener to catch errors during parsing.
+ parser.addErrorListener(parseTreeErrorListener);
+
+ // Begin parsing YANG file and generate parse tree.
+ ParseTree tree = parser.yangfile();
+
+ /**
+ * Throws an parser Exception if exception flag is set i.e. exception has
+ * occurred during parsing.
+ */
+ if (parseTreeErrorListener.isExceptionFlag()) {
+ // Get the exception occurred during parsing.
+ ParserException parserException = parseTreeErrorListener.getParserException();
+ parserException.setFileName(yangFile);
+ throw parserException;
+ }
+
+ // Create a walker to walk the parse tree.
+ ParseTreeWalker walker = new ParseTreeWalker();
+
+ // Create a listener implementation class object.
+ TreeWalkListener treeWalker = new TreeWalkListener();
+
+ /**
+ * Walk parse tree, provide call backs to methods in listener and
+ * build data model tree.
+ */
+ walker.walk(treeWalker, tree);
+
+ // Throws an parser exception which has occurred during listener walk.
+ if (treeWalker.getErrorInformation().isErrorFlag()) {
+ // Create object of listener exception
+ ParserException listenerException = new ParserException();
+ listenerException.setMsg(treeWalker.getErrorInformation().getErrorMsg());
+ listenerException.setFileName(yangFile);
+ throw listenerException;
+ }
+
+ // Returns the Root Node of the constructed data model tree.
+ return treeWalker.getRootNode();
+ }
+}
diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/parserutils/ListenerValidation.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/parserutils/ListenerValidation.java
new file mode 100644
index 0000000..6ecded3
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/parserutils/ListenerValidation.java
@@ -0,0 +1,54 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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
+ *
+ * http://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 org.onosproject.yangutils.parser.impl.parserutils;
+
+import org.onosproject.yangutils.parser.impl.TreeWalkListener;
+
+/**
+ * Its a utility to carry out listener validation.
+ */
+public final class ListenerValidation {
+
+ /**
+ * Creates a new belongto listener.
+ */
+ private ListenerValidation() {
+ }
+
+ /**
+ * Checks if error is set or parsed data stack is empty.
+ *
+ * @param listener Listener's object.
+ * @param errNode parsable node for which validation needs to be done.
+ * @return validation result.
+ */
+ public static boolean preValidation(TreeWalkListener listener, String errNode) {
+
+ // Check whether error found while walking YANG file, if yes return true.
+ if (listener.getErrorInformation().isErrorFlag()) {
+ return true;
+ }
+
+ // If stack is empty it indicates error condition
+ if (listener.getParsedDataStack().empty()) {
+ listener.getErrorInformation().setErrorFlag(true);
+ listener.getErrorInformation().setErrorMsg("Parsable stack empty at" + errNode + "entry");
+ return true;
+ }
+ return false;
+ }
+}
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diff --git a/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/parserutils/ParseTreeErrorListener.java b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/parserutils/ParseTreeErrorListener.java
new file mode 100644
index 0000000..d3926df
--- /dev/null
+++ b/utils/yangutils/src/main/java/org/onosproject/yangutils/parser/impl/parserutils/ParseTreeErrorListener.java
@@ -0,0 +1,65 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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
+ *
+ * http://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 org.onosproject.yangutils.parser.impl.parserutils;
+
+import org.antlr.v4.runtime.BaseErrorListener;
+import org.antlr.v4.runtime.RecognitionException;
+import org.antlr.v4.runtime.Recognizer;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+
+/**
+ * By default, ANTLR sends all errors to standard error, this is changed by
+ * providing this new implementation of interface ANTLRErrorListener. The
+ * interface has a syntaxError() method that applies to both lexer and
+ * parser.
+ */
+public class ParseTreeErrorListener extends BaseErrorListener {
+
+ // Exception of type parser exceptions are catched during parsing.
+ private ParserException parserException = new ParserException();
+
+ // Flag to indicate presence of exception.
+ private boolean exceptionFlag = false;
+
+ /**
+ * Returns the status of exception flag.
+ *
+ * @return flag which contains the status of exception.
+ */
+ public boolean isExceptionFlag() {
+ return exceptionFlag;
+ }
+
+ /**
+ * Returns the parser exception object populated with line, character
+ * position and message.
+ *
+ * @return object of parser exception.
+ */
+ public ParserException getParserException() {
+ return parserException;
+ }
+
+ @Override
+ public void syntaxError(Recognizer<?, ?> recognizer, Object offendingSymbol, int line, int charPositionInLine,
+ String msg, RecognitionException e) {
+ parserException.setLine(line);
+ parserException.setCharPosition(charPositionInLine);
+ parserException.setMsg(msg);
+ exceptionFlag = true;
+ }
+}
\ No newline at end of file
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManagerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManagerTest.java
new file mode 100644
index 0000000..f8a6120
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/impl/YangUtilsParserManagerTest.java
@@ -0,0 +1,103 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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
+ *
+ * http://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 org.onosproject.yangutils.parser.impl;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangNode;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+
+/**
+ * Test case for testing YANG utils parser manager.
+ */
+public class YangUtilsParserManagerTest {
+
+ YangUtilsParserManager manager = new YangUtilsParserManager();
+ File file;
+ BufferedWriter out;
+
+ @Before
+ public void setUp() throws Exception {
+ file = new File("demo.yang");
+ out = new BufferedWriter(new FileWriter(file));
+ }
+ @After
+ public void tearDown() throws Exception {
+ file.delete();
+ }
+
+ /**
+ * This test case checks whether the null pointer exception is generated
+ * when the input YANG file is null.
+ */
+ @Test(expected = NullPointerException.class)
+ public void getDataModelNullFileTest() throws IOException, ParserException {
+ YangUtilsParserManager manager = new YangUtilsParserManager();
+ YangNode node = manager.getDataModel(null);
+ }
+
+ /**
+ * This test case checks whether the io exception is generated
+ * when the input YANG file is non existent.
+ */
+ @Test(expected = IOException.class)
+ public void getDataModelNonExistentFileTest() throws IOException, ParserException {
+
+ YangUtilsParserManager manager = new YangUtilsParserManager();
+ YangNode node = manager.getDataModel("nonexistent.yang");
+ }
+
+ /**
+ * This test case checks if the input YANG file is correct no exception
+ * should be generated.
+ */
+ @Test
+ public void getDataModelCorrectFileTest() throws IOException, ParserException {
+
+ out.write("module ONOS {\n");
+ out.write("yang-version 1;\n");
+ out.write("namespace urn:ietf:params:xml:ns:yang:ietf-ospf;\n");
+ out.write("prefix On;\n");
+ out.write("}\n");
+ out.close();
+
+ YangNode node = manager.getDataModel("demo.yang");
+ }
+
+ /**
+ * This test case checks if the input YANG file with wrong YANG constructs
+ * than parser exception should be generated.
+ */
+ @Test(expected = ParserException.class)
+ public void getDataModelIncorrectFileTest() throws IOException, ParserException {
+
+ out.write("module ONOS {\n");
+ out.write("yang-version 1\n");
+ out.write("namespace urn:ietf:params:xml:ns:yang:ietf-ospf;\n");
+ out.write("prefix On;\n");
+ out.write("}\n");
+ out.close();
+
+ YangNode node = manager.getDataModel("demo.yang");
+ }
+}
\ No newline at end of file
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/parseutils/ListenerValidationTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/parseutils/ListenerValidationTest.java
new file mode 100644
index 0000000..c047f2b
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/parseutils/ListenerValidationTest.java
@@ -0,0 +1,103 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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
+ *
+ * http://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 org.onosproject.yangutils.parser.parseutils;
+
+import org.junit.Test;
+import org.onosproject.yangutils.datamodel.YangRevision;
+import org.onosproject.yangutils.parser.impl.TreeWalkListener;
+import org.onosproject.yangutils.parser.impl.parserutils.ListenerError;
+import org.onosproject.yangutils.parser.impl.parserutils.ListenerValidation;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Test case for testing listener validation util.
+ */
+public class ListenerValidationTest {
+
+ /**
+ * This test case checks in case error pre-exists, listener validate
+ * function returns true.
+ */
+ @Test
+ public void listenerValidationErrorExists() {
+
+ // Create an test error.
+ ListenerError testError = new ListenerError();
+ testError.setErrorFlag(true);
+ testError.setErrorMsg("Test Error");
+
+ // Create test walker and assign test error to it.
+ TreeWalkListener testWalker = new TreeWalkListener();
+ testWalker.setErrorInformation(testError);
+
+ // Create a temporary node of parsable.
+ YangRevision tmpNode = new YangRevision();
+ testWalker.getParsedDataStack().push(tmpNode);
+
+ boolean errorFlag = ListenerValidation.preValidation(testWalker, "ErrorTest");
+
+ /**
+ * Check for the values set in syntax error function. If not set properly
+ * report an assert.
+ */
+ assertThat(errorFlag, is(true));
+ }
+
+ /**
+ * This test case checks in case parsable stack is empty, listener validate
+ * function returns true.
+ */
+ @Test
+ public void listenerValidationEmptyStack() {
+
+ // Create test walker and assign test error to it.
+ TreeWalkListener testWalker = new TreeWalkListener();
+
+ boolean errorFlag = ListenerValidation.preValidation(testWalker, "ErrorTest");
+
+ /**
+ * Check for the values set in syntax error function. If not set properly
+ * report an assert.
+ */
+ assertThat(errorFlag, is(true));
+ }
+
+ /**
+ * This test case checks in case of error doesn't pre-exists and stack is,
+ * non empty, listener validate function returns false.
+ */
+ @Test
+ public void listenerValidationNoErrorNotExists() {
+
+ // Create test walker and assign test error to it.
+ TreeWalkListener testWalker = new TreeWalkListener();
+
+ // Create a temporary node of parsable.
+ YangRevision tmpNode = new YangRevision();
+ testWalker.getParsedDataStack().push(tmpNode);
+
+ boolean errorFlag = ListenerValidation.preValidation(testWalker, "ErrorTest");
+
+ /**
+ * Check for the values set in syntax error function. If not set properly
+ * report an assert.
+ */
+ assertThat(errorFlag, is(false));
+ }
+}
\ No newline at end of file
diff --git a/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/parseutils/ParseTreeErrorListenerTest.java b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/parseutils/ParseTreeErrorListenerTest.java
new file mode 100644
index 0000000..f91797e
--- /dev/null
+++ b/utils/yangutils/src/test/java/org/onosproject/yangutils/parser/parseutils/ParseTreeErrorListenerTest.java
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2016 Open Networking Laboratory
+ *
+ * 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
+ *
+ * http://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 org.onosproject.yangutils.parser.impl.parseutils;
+
+import org.antlr.v4.runtime.ANTLRFileStream;
+import org.antlr.v4.runtime.ANTLRInputStream;
+import org.antlr.v4.runtime.CommonTokenStream;
+import org.antlr.v4.runtime.tree.ParseTree;
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.onosproject.yangutils.parser.antlrgencode.GeneratedYangLexer;
+import org.onosproject.yangutils.parser.antlrgencode.GeneratedYangParser;
+import org.onosproject.yangutils.parser.exceptions.ParserException;
+import org.onosproject.yangutils.parser.impl.YangUtilsParserManager;
+import org.onosproject.yangutils.parser.impl.parserutils.ParseTreeErrorListener;
+
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Test case for testing parse tree error listener.
+ */
+public class ParseTreeErrorListenerTest {
+
+ YangUtilsParserManager manager = new YangUtilsParserManager();
+ File file;
+ BufferedWriter out;
+
+ @Before
+ public void setUp() throws Exception {
+ file = new File("demo.yang");
+ out = new BufferedWriter(new FileWriter(file));
+ }
+ @After
+ public void tearDown() throws Exception {
+ file.delete();
+ }
+
+ /**
+ * This test case checks whether the error received from parser is correctly
+ * handled.
+ */
+ @Test
+ public void syntaxErrorValidationTest() throws IOException {
+
+ out.write("module ONOS {\n");
+ out.write("yang-version 1\n");
+ out.write("namespace urn:ietf:params:xml:ns:yang:ietf-ospf;\n");
+ out.write("prefix On;\n");
+ out.write("}\n");
+ out.close();
+
+ ANTLRInputStream input = new ANTLRFileStream("demo.yang");
+
+ // Create a lexer that feeds off of input char stream.
+ GeneratedYangLexer lexer = new GeneratedYangLexer(input);
+ // Create a buffer of tokens pulled from the lexer.
+ CommonTokenStream tokens = new CommonTokenStream(lexer);
+ // Create a parser that feeds off the tokens buffer.
+ GeneratedYangParser parser = new GeneratedYangParser(tokens);
+ // Remove console error listener.
+ parser.removeErrorListeners();
+ // Create instance of customized error listener.
+ ParseTreeErrorListener parseTreeErrorListener = new ParseTreeErrorListener();
+ // Add customized error listener to catch errors during parsing.
+ parser.addErrorListener(parseTreeErrorListener);
+ // Begin parsing YANG file and generate parse tree.
+ ParseTree tree = parser.yangfile();
+ // Get the exception occurred during parsing.
+ ParserException parserException = parseTreeErrorListener.getParserException();
+
+ /**
+ * Check for the values set in syntax error function. If not set properly
+ * report an assert.
+ */
+ assertThat(parseTreeErrorListener.isExceptionFlag(), is(true));
+ assertThat(parserException.getLineNumber(), is(3));
+ assertThat(parserException.getCharPositionInLine(), is(0));
+ }
+}
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