yang/yang-parser-impl/src/main/java/org/opendaylight/yangtools/yang/parser/util/TextToASTTransformer.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
   3  * This program and the accompanying materials are made available under the
   4  * terms of the Eclipse Public License v1.0 which accompanies this distribution,
   5  * and is available at http://www.eclipse.org/legal/epl-v10.html
   6  */
   7 package org.opendaylight.yangtools.yang.parser.util;
   8
   9 import com.google.common.base.Charsets;
  10 import com.google.common.base.Function;
  11 import com.google.common.base.Preconditions;
  12 import com.google.common.io.CharStreams;
  13 import com.google.common.io.InputSupplier;
  14 import com.google.common.util.concurrent.CheckedFuture;
  15 import com.google.common.util.concurrent.Futures;
  16 import com.google.common.util.concurrent.ListeningExecutorService;
  17
  18 import java.io.IOException;
  19 import java.io.InputStream;
  20 import java.util.concurrent.Callable;
  21
  22 import org.antlr.v4.runtime.tree.ParseTreeWalker;
  23 import org.opendaylight.yangtools.antlrv4.code.gen.YangParser.YangContext;
  24 import org.opendaylight.yangtools.util.concurrent.ExceptionMapper;
  25 import org.opendaylight.yangtools.yang.model.parser.api.YangSyntaxErrorException;
  26 import org.opendaylight.yangtools.yang.model.repo.api.YangTextSchemaSource;
  27 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceTransformationException;
  28 import org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceTransformer;
  29 import org.opendaylight.yangtools.yang.parser.impl.YangModelBasicValidationListener;
  30 import org.opendaylight.yangtools.yang.parser.impl.YangParserImpl;
  31 import org.slf4j.Logger;
  32 import org.slf4j.LoggerFactory;
  33
  34 /**
  35  * A {@link SchemaSourceTransformer} which handles translation of models from
  36  * {@link YangTextSchemaSource} representation into {@link ASTSchemaSource}.
  37  *
  38  * While this class is currently used explicitly, its long-term purpose is to
  39  * be registered with a {@link org.opendaylight.yangtools.yang.model.repo.spi.SchemaSourceRegistry}
  40  * and be invoked on demand when the processing pipeline requests the
  41  * ASTSchemaSource representation.
  42  */
  43 public final class TextToASTTransformer implements SchemaSourceTransformer<YangTextSchemaSource, ASTSchemaSource> {
  44     private static final Logger LOG = LoggerFactory.getLogger(TextToASTTransformer.class);
  45     private static final Function<Exception, SchemaSourceTransformationException> MAPPER = new ExceptionMapper<SchemaSourceTransformationException>("Source transformation", SchemaSourceTransformationException.class) {
  46         @Override
  47         protected SchemaSourceTransformationException newWithCause(final String message, final Throwable cause) {
  48             return new SchemaSourceTransformationException(message, cause);
  49         }
  50     };
  51
  52     private final ListeningExecutorService executor;
  53
  54     private TextToASTTransformer(final ListeningExecutorService executor) {
  55         this.executor = Preconditions.checkNotNull(executor);
  56     }
  57
  58     public static final TextToASTTransformer create(final ListeningExecutorService executor) {
  59         return new TextToASTTransformer(executor);
  60     }
  61
  62     @Override
  63     public Class<YangTextSchemaSource> getInputRepresentation() {
  64         return YangTextSchemaSource.class;
  65     }
  66
  67     @Override
  68     public Class<ASTSchemaSource> getOutputRepresentation() {
  69         return ASTSchemaSource.class;
  70     }
  71
  72     @Override
  73     public CheckedFuture<ASTSchemaSource, SchemaSourceTransformationException> transformSchemaSource(final YangTextSchemaSource source) {
  74         return Futures.makeChecked(executor.submit(new Callable<ASTSchemaSource>() {
  75             @Override
  76             public ASTSchemaSource call() throws IOException, YangSyntaxErrorException {
  77                 try (InputStream is = source.openStream()) {
  78                     final YangContext ctx = YangParserImpl.parseYangSource(is);
  79                     LOG.debug("Model {} parsed successfully", source);
  80
  81                     final ParseTreeWalker walker = new ParseTreeWalker();
  82                     final YangModelBasicValidationListener validator = new YangModelBasicValidationListener();
  83                     walker.walk(validator, ctx);
  84                     LOG.debug("Model {} validated successfully", source);
  85
  86                     // Backwards compatibility
  87                     final String text = CharStreams.toString(
  88                             CharStreams.newReaderSupplier(new InputSupplier<InputStream>() {
  89                                 @Override
  90                                 public InputStream getInput() throws IOException {
  91                                     return source.openStream();
  92                                 }
  93                             }, Charsets.UTF_8));
  94
  95                     return ASTSchemaSource.create(source.getIdentifier().getName(), ctx, text);
  96                 }
  97             }
  98         }), MAPPER);
  99     }
 100
 101     @Override
 102     public int getCost() {
 103         // We perform a direct translation, so the cost is 1.
 104         return 1;
 105     }
 106 }