DefaultModelProcessor.java
/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.maven.impl.model;
import java.io.ByteArrayInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Objects;
import java.util.Optional;
import org.apache.maven.api.annotations.Nullable;
import org.apache.maven.api.di.Inject;
import org.apache.maven.api.di.Named;
import org.apache.maven.api.di.Singleton;
import org.apache.maven.api.model.Model;
import org.apache.maven.api.services.ModelSource;
import org.apache.maven.api.services.Source;
import org.apache.maven.api.services.Sources;
import org.apache.maven.api.services.model.ModelProcessor;
import org.apache.maven.api.services.xml.ModelXmlFactory;
import org.apache.maven.api.services.xml.XmlReaderException;
import org.apache.maven.api.services.xml.XmlReaderRequest;
import org.apache.maven.api.spi.ModelParser;
import org.apache.maven.api.spi.ModelParserException;
/**
*
* Note: uses @Typed to limit the types it is available for injection to just ModelProcessor.
*
* This is because the ModelProcessor interface extends ModelLocator and ModelReader. If we
* made this component available under all its interfaces then it could end up being injected
* into itself leading to a stack overflow.
*
* A side effect of using @Typed is that it translates to explicit bindings in the container.
* So instead of binding the component under a 'wildcard' key it is now bound with an explicit
* key. Since this is a default component; this will be a plain binding of ModelProcessor to
* this implementation type; that is, no hint/name.
*
* This leads to a second side effect in that any @Inject request for just ModelProcessor in
* the same injector is immediately matched to this explicit binding, which means extensions
* cannot override this binding. This is because the lookup is always short-circuited in this
* specific situation (plain @Inject request, and plain explicit binding for the same type.)
*
* The simplest solution is to use a custom @Named here so it isn't bound under the plain key.
* This is only necessary for default components using @Typed that want to support overriding.
*
* As a non-default component this now gets a negative priority relative to other implementations
* of the same interface. Since we want to allow overriding this doesn't matter in this case.
* (if it did we could add @Priority of 0 to match the priority given to default components.)
*/
@Named
@Singleton
public class DefaultModelProcessor implements ModelProcessor {
private final ModelXmlFactory modelXmlFactory;
private final Map<String, ModelParser> modelParsers;
@Inject
public DefaultModelProcessor(ModelXmlFactory modelXmlFactory, @Nullable Map<String, ModelParser> modelParsers) {
this.modelXmlFactory = modelXmlFactory;
this.modelParsers = modelParsers != null ? modelParsers : Map.of();
}
@Override
public Path locateExistingPom(Path projectDirectory) {
// Note that the ModelProcessor#locatePom never returns null
// while the ModelParser#locatePom needs to return an existing path!
Path pom = modelParsers.values().stream()
.map(m -> m.locate(projectDirectory)
.map(org.apache.maven.api.services.Source::getPath)
.orElse(null))
.filter(Objects::nonNull)
.findFirst()
.orElseGet(() -> doLocateExistingPom(projectDirectory));
if (pom != null && !pom.equals(projectDirectory) && !pom.getParent().equals(projectDirectory)) {
throw new IllegalArgumentException("The POM found does not belong to the given directory: " + pom);
}
return pom;
}
@Override
public Model read(Source source, Map<String, ?> options) throws ModelParserException {
Objects.requireNonNull(source, "source cannot be null");
Path pomFile = source.getPath();
if (pomFile != null) {
// a parser may locate the project directory itself rather than a file within it
Path projectDirectory = Files.isDirectory(pomFile) ? pomFile : pomFile.getParent();
Map<String, ModelParserException> exceptions = new LinkedHashMap<>();
for (Map.Entry<String, ModelParser> parser : modelParsers.entrySet()) {
try {
Optional<Model> model = parser.getValue().locateAndParse(projectDirectory, options);
if (model.isPresent()) {
return model.get().withPomFile(pomFile);
}
} catch (ModelParserException e) {
exceptions.put(parser.getKey(), e);
}
}
try {
return doRead(source, options);
} catch (ModelParserException e) {
if (!exceptions.isEmpty()) {
ModelParserException mpe =
new ModelParserException(buildDetailedErrorMessage(pomFile, exceptions, e), e);
exceptions.values().forEach(mpe::addSuppressed);
throw mpe;
}
throw e;
}
} else {
return doRead(source, options);
}
}
/**
* Implements the deprecated bridge for backward compatibility.
* Delegates to {@link #read(Source, Map)}, then re-throws {@link XmlReaderException}
* or {@link IOException} from the cause when possible.
*
* @deprecated Use {@link #read(Source, Map)} instead.
*/
@Deprecated(since = "4.2.0")
@Override
public Model read(XmlReaderRequest request) throws IOException, XmlReaderException {
Objects.requireNonNull(request, "request cannot be null");
Source source = toSource(request);
try {
return read(
source,
request.getTransformer() != null
? Map.of(
ModelParser.STRICT,
request.isStrict(),
ModelProcessor.TRANSFORMER,
request.getTransformer())
: Map.of(ModelParser.STRICT, request.isStrict()));
} catch (ModelParserException e) {
// Unwrap one level: doRead wraps XmlReaderException/IOException as the direct cause
if (e.getCause() instanceof XmlReaderException xre) {
throw xre;
}
if (e.getCause() instanceof IOException ioe) {
throw ioe;
}
throw new XmlReaderException(e.getMessage(), null, e);
}
}
private static Source toSource(XmlReaderRequest request) {
if (request.getInputStream() == null
&& request.getPath() == null
&& request.getReader() == null
&& request.getURL() != null) {
return Sources.urlSource(request.getURL(), request.getModelId());
}
// Always return a ModelSource so modelId is preserved.
return new ModelSource() {
@Override
public Path getPath() {
return request.getPath();
}
@Override
public InputStream openStream() throws IOException {
if (request.getInputStream() != null) {
return request.getInputStream();
} else if (request.getURL() != null) {
return request.getURL().openStream();
} else if (request.getPath() != null) {
return Files.newInputStream(request.getPath());
} else if (request.getReader() != null) {
// Note: when the request carries a Reader (already decoded chars), we re-encode as UTF-8.
// If the original XML declared a non-UTF-8 encoding (e.g. ISO-8859-1), the declaration
// will no longer match the actual byte encoding. In practice Maven POMs are UTF-8 or
// ASCII so this is safe, but callers providing a Reader for non-UTF-8 content should
// use InputStream instead.
StringBuilder sb = new StringBuilder();
char[] buf = new char[4096];
int n;
while ((n = request.getReader().read(buf)) != -1) {
sb.append(buf, 0, n);
}
return new ByteArrayInputStream(sb.toString().getBytes(StandardCharsets.UTF_8));
}
throw new IOException("No input stream available in request");
}
@Override
public String getLocation() {
if (request.getLocation() != null) {
return request.getLocation();
}
if (request.getPath() != null) {
return request.getPath().toString();
}
if (request.getURL() != null) {
return request.getURL().toExternalForm();
}
return "<unknown>";
}
@Override
public Source resolve(String relative) {
if (request.getPath() != null) {
return toSource(XmlReaderRequest.builder()
.path(request.getPath().resolve(relative))
.build());
}
return null;
}
@Override
public ModelSource resolve(ModelLocator modelLocator, String relative) {
return null;
}
@Override
public String getModelId() {
return request.getModelId();
}
};
}
private Path doLocateExistingPom(Path project) {
if (project == null) {
project = Paths.get(System.getProperty("user.dir"));
}
if (Files.isDirectory(project)) {
Path pom = project.resolve("pom.xml");
return Files.isRegularFile(pom) ? pom : null;
} else if (Files.isRegularFile(project)) {
return project;
} else {
return null;
}
}
private Model doRead(Source source, Map<String, ?> options) throws ModelParserException {
boolean strict = isStrict(options);
XmlReaderRequest.Transformer transformer = getTransformer(options);
try (InputStream is = source.openStream()) {
XmlReaderRequest.XmlReaderRequestBuilder builder = XmlReaderRequest.builder()
.strict(strict)
.location(source.getLocation())
.path(source.getPath())
.inputStream(is)
.transformer(transformer);
if (source instanceof ModelSource ms) {
builder.modelId(ms.getModelId());
}
return modelXmlFactory.read(builder.build());
} catch (XmlReaderException e) {
if (e.getLocation() != null) {
throw new ModelParserException(
e.getMessage(),
e.getLocation().getLineNumber(),
e.getLocation().getColumnNumber(),
e);
}
throw new ModelParserException(e.getMessage(), e);
} catch (IOException e) {
throw new ModelParserException(e.getMessage(), e);
}
}
private boolean isStrict(Map<String, ?> options) {
Object value = (options != null) ? options.get(ModelParser.STRICT) : null;
return value == null || Boolean.parseBoolean(value.toString());
}
private XmlReaderRequest.Transformer getTransformer(Map<String, ?> options) {
Object value = (options != null) ? options.get(ModelProcessor.TRANSFORMER) : null;
if (value instanceof XmlReaderRequest.Transformer t) {
return t;
}
return new ModelInterningTransformer();
}
private String buildDetailedErrorMessage(
Path pomFile, Map<String, ModelParserException> parserExceptions, Exception defaultReaderException) {
StringBuilder message = new StringBuilder();
message.append("Unable to parse POM ").append(pomFile).append(System.lineSeparator());
if (!parserExceptions.isEmpty()) {
message.append(" Tried ")
.append(parserExceptions.size())
.append(" parser")
.append(parserExceptions.size() > 1 ? "s" : "")
.append(":")
.append(System.lineSeparator());
for (Map.Entry<String, ModelParserException> entry : parserExceptions.entrySet()) {
ModelParserException e = entry.getValue();
message.append(" ").append(entry.getKey()).append(") ");
String parserMessage = e.getMessage();
if (parserMessage != null && !parserMessage.isEmpty()) {
message.append(parserMessage);
} else {
message.append(e.getClass().getSimpleName());
}
if (e.getLineNumber() > 0) {
message.append(" at line ").append(e.getLineNumber());
if (e.getColumnNumber() > 0) {
message.append(", column ").append(e.getColumnNumber());
}
}
if (e.getCause() != null && e.getCause().getMessage() != null) {
String causeMessage = e.getCause().getMessage();
if (parserMessage == null || !parserMessage.contains(causeMessage)) {
message.append(": ").append(causeMessage);
}
}
message.append(System.lineSeparator());
}
}
message.append(" default) XML reader also failed: ");
String defaultMessage = defaultReaderException.getMessage();
if (defaultMessage != null && !defaultMessage.isEmpty()) {
message.append(defaultMessage);
} else {
message.append(defaultReaderException.getClass().getSimpleName());
}
return message.toString();
}
}