// Copyright 2014 The Bazel Authors. All rights reserved.
//
// 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 com.google.devtools.build.lib.rules.java;
import static java.nio.charset.StandardCharsets.UTF_8;
import com.google.common.annotations.VisibleForTesting;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import com.google.devtools.build.lib.actions.ActionExecutionContext;
import com.google.devtools.build.lib.actions.ActionOwner;
import com.google.devtools.build.lib.actions.Artifact;
import com.google.devtools.build.lib.analysis.BuildInfo;
import com.google.devtools.build.lib.analysis.WorkspaceStatusAction;
import com.google.devtools.build.lib.analysis.WorkspaceStatusAction.Key;
import com.google.devtools.build.lib.analysis.actions.AbstractFileWriteAction;
import com.google.devtools.build.lib.util.Fingerprint;
import com.google.devtools.build.lib.util.Preconditions;
import java.io.IOException;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Writer;
import java.util.Collection;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Properties;
/**
* An action that creates a Java properties file containing the build informations.
*/
public class WriteBuildInfoPropertiesAction extends AbstractFileWriteAction {
private static final String GUID = "19e543c2-3ce4-4aef-80f5-4f8abf4b064f";
private final ImmutableList<Artifact> valueArtifacts;
private final BuildInfoPropertiesTranslator keyTranslations;
private final boolean includeVolatile;
private final boolean includeNonVolatile;
private final TimestampFormatter timestampFormatter;
/**
* An interface to format a timestamp. We are using our custom one to avoid external dependency.
*/
public static interface TimestampFormatter {
/**
* Return a human readable string for the given {@code timestamp}. {@code timestamp} is given
* in milliseconds since 1st of January 1970 at 0am UTC.
*/
public String format(long timestamp);
}
/**
* A wrapper around a {@link Writer} that skips the first line assuming the line is pure ASCII. It
* can be used to strip the timestamp comment that {@link Properties#store(Writer, String)} adds.
*/
@VisibleForTesting
static class StripFirstLineWriter extends Writer {
private final Writer writer;
private boolean newlineFound = false;
StripFirstLineWriter(OutputStream out) {
this.writer = new OutputStreamWriter(out, UTF_8);
}
@Override
public void write(char[] cbuf, int off, int len) throws IOException {
if (!newlineFound) {
while (len > 0 && cbuf[off] != '\n') {
off++;
len--;
}
if (len > 0) {
newlineFound = true;
off++;
len--;
}
}
if (len > 0) {
writer.write(cbuf, off, len);
}
}
@Override
public void flush() throws IOException {
writer.flush();
}
@Override
public void close() throws IOException {
writer.close();
}
}
/**
* Creates an action that writes a Java property files with build information.
*
* <p>It reads the set of build info keys from an action context that is usually contributed to
* Blaze by the workspace status module, and the value associated with said keys from the
* workspace status files (stable and volatile) written by the workspace status action. The files
* generated by this action serve as input to the
* {@link com.google.devtools.build.singlejar.SingleJar} program.
*
* <p>Without input artifacts, this action uses redacted build information.
*
* @param inputs Artifacts that contain build information, or an empty collection to use redacted
* build information
* @param output output the properties file Artifact created by this action
* @param keyTranslations how to translates available keys. See
* {@link BuildInfoPropertiesTranslator}.
* @param includeVolatile whether the set of key to write are giving volatile keys or not
* @param includeNonVolatile whether the set of key to write are giving non-volatile keys or not
* @param timestampFormatter formats dates printed in the properties file
*/
public WriteBuildInfoPropertiesAction(Collection<Artifact> inputs, Artifact output,
BuildInfoPropertiesTranslator keyTranslations, boolean includeVolatile,
boolean includeNonVolatile, TimestampFormatter timestampFormatter) {
super(ActionOwner.SYSTEM_ACTION_OWNER, inputs, output, /* makeExecutable= */ false);
this.keyTranslations = keyTranslations;
this.includeVolatile = includeVolatile;
this.includeNonVolatile = includeNonVolatile;
this.timestampFormatter = timestampFormatter;
valueArtifacts = ImmutableList.copyOf(inputs);
if (!inputs.isEmpty()) {
// With non-empty inputs we should not generate both volatile and non-volatile data
// in the same properties file.
Preconditions.checkState(includeVolatile ^ includeNonVolatile);
}
Preconditions.checkState(
output.isConstantMetadata() == (includeVolatile && !inputs.isEmpty()));
}
@Override
public DeterministicWriter newDeterministicWriter(final ActionExecutionContext ctx) {
final long timestamp = System.currentTimeMillis();
return new DeterministicWriter() {
@Override
public void writeOutputFile(OutputStream out) throws IOException {
WorkspaceStatusAction.Context context =
ctx.getExecutor().getContext(WorkspaceStatusAction.Context.class);
Map<String, String> values = new LinkedHashMap<>();
for (Artifact valueFile : valueArtifacts) {
values.putAll(WorkspaceStatusAction.parseValues(valueFile.getPath()));
}
Map<String, String> keys = new HashMap<>();
if (includeVolatile) {
addValues(keys, values, context.getVolatileKeys());
long timeMillis = timestamp;
Key sourceDateEpoch = context.getStableKeys().get(BuildInfo.SOURCE_DATE_EPOCH);
if (sourceDateEpoch != null) {
timeMillis = Long.valueOf(sourceDateEpoch.getDefaultValue()) * 1000L;
}
keys.put("BUILD_TIMESTAMP", Long.toString(timeMillis / 1000));
keys.put("BUILD_TIME", timestampFormatter.format(timeMillis));
}
addValues(keys, values, context.getStableKeys());
Properties properties = new Properties();
keyTranslations.translate(keys, properties);
properties.store(new StripFirstLineWriter(out), null);
}
};
}
private void addValues(Map<String, String> result, Map<String, String> values,
Map<String, Key> keys) {
boolean redacted = values.isEmpty();
for (Map.Entry<String, WorkspaceStatusAction.Key> key : keys.entrySet()) {
if (key.getValue().isInLanguage("Java")) {
result.put(key.getKey(), gePropertyValue(values, redacted, key));
}
}
}
private static String gePropertyValue(Map<String, String> values, boolean redacted,
Map.Entry<String, WorkspaceStatusAction.Key> key) {
return redacted ? key.getValue().getRedactedValue()
: values.containsKey(key.getKey()) ? values.get(key.getKey())
: key.getValue().getDefaultValue();
}
@Override
protected String computeKey() {
Fingerprint f = new Fingerprint();
f.addString(GUID);
f.addString(keyTranslations.computeKey());
f.addBoolean(includeVolatile);
f.addBoolean(includeNonVolatile);
return f.hexDigestAndReset();
}
@Override
public boolean executeUnconditionally() {
return isVolatile();
}
@Override
public boolean isVolatile() {
return includeVolatile && !Iterables.isEmpty(getInputs());
}
}