/*
* Copyright 2017 The Closure Compiler Authors.
*
* 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.javascript.jscomp.deps;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.ImmutableSortedSet;
import com.google.javascript.jscomp.CheckLevel;
import com.google.javascript.jscomp.ErrorHandler;
import com.google.javascript.jscomp.JSError;
import java.util.Comparator;
import java.util.Map;
import java.util.SortedSet;
import java.util.TreeSet;
import javax.annotation.Nullable;
/**
* Resolution algorithm for NodeJS. See https://nodejs.org/api/modules.html#modules_all_together
*
* <p>Unambiguous paths are file paths resolved from the current script. Ambiguous paths are located
* within the nearest node_modules folder ancestor.
*/
public class NodeModuleResolver extends ModuleResolver {
private static final String[] FILE_EXTENSIONS_TO_SEARCH = {"", ".js", ".json"};
private static final String[] FILES_TO_SEARCH = {
ModuleLoader.MODULE_SLASH + "package.json",
ModuleLoader.MODULE_SLASH + "index.js",
ModuleLoader.MODULE_SLASH + "index.json"
};
/** Named modules found in node_modules folders */
private final ImmutableMap<String, String> packageJsonMainEntries;
/** Named modules found in node_modules folders */
private final ImmutableSortedSet<String> nodeModulesFolders;
/**
* Build a list of node module paths. Given the following path:
*
* <p>/foo/node_modules/bar/node_modules/baz/foo_bar_baz.js
*
* <p>Return a set containing:
*
* <p>/foo/ /foo/node_modules/bar/
*
* @param modulePaths Set of all module paths where the key is the module path normalized to have
* a leading slash
* @return A sorted set with the longest paths first where each entry is the folder containing a
* node_modules sub-folder.
*/
private static ImmutableSortedSet<String> buildNodeModulesFoldersRegistry(
Iterable<String> modulePaths) {
SortedSet<String> registry =
new TreeSet<>(
new Comparator<String>() {
@Override
public int compare(String a, String b) {
// Order longest path first
int comparison = Integer.compare(b.length(), a.length());
if (comparison != 0) {
return comparison;
}
return a.compareTo(b);
}
});
// For each modulePath, find all the node_modules folders
// There might be more than one:
// /foo/node_modules/bar/node_modules/baz/foo_bar_baz.js
// Should add:
// /foo/ -> bar/node_modules/baz/foo_bar_baz.js
// /foo/node_modules/bar/ -> baz/foo_bar_baz.js
for (String modulePath : modulePaths) {
String[] nodeModulesDirs = modulePath.split("/node_modules/");
String parentPath = "";
for (int i = 0; i < nodeModulesDirs.length - 1; i++) {
if (i + 1 < nodeModulesDirs.length) {
parentPath += nodeModulesDirs[i] + "/";
}
registry.add(parentPath);
parentPath += "node_modules/";
}
}
return ImmutableSortedSet.copyOfSorted(registry);
}
public NodeModuleResolver(
ImmutableSet<String> modulePaths,
ImmutableList<String> moduleRootPaths,
Map<String, String> packageJsonMainEntries,
ErrorHandler errorHandler) {
super(modulePaths, moduleRootPaths, errorHandler);
this.nodeModulesFolders = buildNodeModulesFoldersRegistry(modulePaths);
if (packageJsonMainEntries == null) {
this.packageJsonMainEntries = ImmutableMap.of();
} else {
this.packageJsonMainEntries = buildPackageJsonMainEntries(packageJsonMainEntries);
}
}
/**
* @param packageJsonMainEntries a map with keys that are package.json file paths and values which
* are the "main" entry from the package.json. "main" entries are absolute paths rooted from
* the folder containing the package.json file.
*/
private ImmutableMap<String, String> buildPackageJsonMainEntries(
Map<String, String> packageJsonMainEntries) {
ImmutableMap.Builder<String, String> builder = ImmutableMap.builder();
for (Map.Entry<String, String> packageJsonMainEntry : packageJsonMainEntries.entrySet()) {
String entryKey = packageJsonMainEntry.getKey();
if (ModuleLoader.isAmbiguousIdentifier(entryKey)) {
entryKey = ModuleLoader.MODULE_SLASH + entryKey;
}
builder.put(entryKey, packageJsonMainEntry.getValue());
}
return builder.build();
}
Map<String, String> getPackageJsonMainEntries() {
return this.packageJsonMainEntries;
}
@Nullable
public String resolveJsModule(
String scriptAddress, String moduleAddress, String sourcename, int lineno, int colno) {
String loadAddress;
if (ModuleLoader.isAbsoluteIdentifier(moduleAddress)
|| ModuleLoader.isRelativeIdentifier(moduleAddress)) {
loadAddress = resolveJsModuleNodeFileOrDirectory(scriptAddress, moduleAddress);
} else {
loadAddress = resolveJsModuleFromRegistry(scriptAddress, moduleAddress);
}
if (loadAddress == null) {
errorHandler.report(
CheckLevel.WARNING,
JSError.make(sourcename, lineno, colno, ModuleLoader.LOAD_WARNING, moduleAddress));
}
return loadAddress;
}
public String resolveJsModuleFile(String scriptAddress, String moduleAddress) {
for (int i = 0; i < FILE_EXTENSIONS_TO_SEARCH.length; i++) {
String loadAddress = locate(scriptAddress, moduleAddress + FILE_EXTENSIONS_TO_SEARCH[i]);
if (loadAddress != null) {
return loadAddress;
}
}
return null;
}
@Nullable
private String resolveJsModuleNodeFileOrDirectory(String scriptAddress, String moduleAddress) {
String loadAddress;
loadAddress = resolveJsModuleFile(scriptAddress, moduleAddress);
if (loadAddress == null) {
loadAddress = resolveJsModuleNodeDirectory(scriptAddress, moduleAddress);
}
return loadAddress;
}
@Nullable
private String resolveJsModuleNodeDirectory(String scriptAddress, String moduleAddress) {
if (moduleAddress.endsWith(ModuleLoader.MODULE_SLASH)) {
moduleAddress = moduleAddress.substring(0, moduleAddress.length() - 1);
}
// Load as a file
for (int i = 0; i < FILES_TO_SEARCH.length; i++) {
String loadAddress = locate(scriptAddress, moduleAddress + FILES_TO_SEARCH[i]);
if (loadAddress != null) {
if (FILES_TO_SEARCH[i].equals(ModuleLoader.MODULE_SLASH + "package.json")) {
if (packageJsonMainEntries.containsKey(loadAddress)) {
return resolveJsModuleFile(scriptAddress, packageJsonMainEntries.get(loadAddress));
}
} else {
return loadAddress;
}
}
}
return null;
}
@Nullable
private String resolveJsModuleFromRegistry(String scriptAddress, String moduleAddress) {
for (String nodeModulesFolder : nodeModulesFolders) {
String normalizedScriptAddress =
(ModuleLoader.isAmbiguousIdentifier(scriptAddress) ? ModuleLoader.MODULE_SLASH : "")
+ scriptAddress;
if (!normalizedScriptAddress.startsWith(nodeModulesFolder)) {
continue;
}
// Load as a file
String fullModulePath = nodeModulesFolder + "node_modules/" + moduleAddress;
String loadAddress = resolveJsModuleFile(scriptAddress, fullModulePath);
if (loadAddress == null) {
// Load as a directory
loadAddress = resolveJsModuleNodeDirectory(scriptAddress, fullModulePath);
}
if (loadAddress != null) {
return loadAddress;
}
}
return null;
}
}