// 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.docgen;
import com.google.common.collect.ImmutableList;
import com.google.devtools.build.lib.analysis.ConfiguredRuleClassProvider;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
/**
* A helper class to load and store printable build rule documentation. The doc
* printed here doesn't contain attribute and implicit output definitions, just
* the general rule documentation and examples.
*/
public class BlazeRuleHelpPrinter {
private static Map<String, RuleDocumentation> ruleDocMap = null;
/**
* Returns the documentation of the given rule to be printed on the console.
*/
public static String getRuleDoc(String ruleName, ConfiguredRuleClassProvider provider) {
if (ruleDocMap == null) {
try {
BuildDocCollector collector = new BuildDocCollector(provider, false);
Map<String, RuleDocumentation> ruleDocs = collector.collect(
ImmutableList.of("java/com/google/devtools/build/lib/view",
"java/com/google/devtools/build/lib/rules"), null);
ruleDocMap = new HashMap<>();
for (RuleDocumentation ruleDoc : ruleDocs.values()) {
ruleDocMap.put(ruleDoc.getRuleName(), ruleDoc);
}
} catch (BuildEncyclopediaDocException e) {
return e.getErrorMsg();
} catch (IOException e) {
return e.getMessage();
}
}
// TODO(fwe): generate the rule documentation when building the Bazel binary and ship
// the text documentation with the binary.
// The Bazel binary may not contain the rule sources, which means that the documentation
// retrieval step would fail with an exception.
if (!ruleDocMap.containsKey(ruleName)) {
return String.format("Documentation for rule %s is not part of the binary.\n", ruleName);
}
return "Rule " + ruleName + ":"
+ ruleDocMap.get(ruleName).getCommandLineDocumentation() + "\n";
}
}