| // 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.python; |
| |
| import com.google.common.collect.ImmutableSet; |
| import com.google.devtools.build.lib.actions.Artifact; |
| import com.google.devtools.build.lib.actions.ArtifactRoot; |
| import com.google.devtools.build.lib.analysis.FilesToRunProvider; |
| import com.google.devtools.build.lib.analysis.RuleContext; |
| import com.google.devtools.build.lib.analysis.Runfiles; |
| import com.google.devtools.build.lib.analysis.TransitionMode; |
| import com.google.devtools.build.lib.analysis.actions.CustomCommandLine; |
| import com.google.devtools.build.lib.analysis.actions.SpawnAction; |
| import com.google.devtools.build.lib.util.FileType; |
| import com.google.devtools.build.lib.vfs.PathFragment; |
| import java.util.HashMap; |
| import java.util.HashSet; |
| import java.util.Map; |
| import java.util.Set; |
| import java.util.function.Predicate; |
| import javax.annotation.Nullable; |
| |
| /** Various utility methods for Python support. */ |
| public final class PythonUtils { |
| public static final PathFragment INIT_PY = PathFragment.create("__init__.py"); |
| public static final PathFragment INIT_PYC = PathFragment.create("__init__.pyc"); |
| public static final PathFragment PYCACHE = PathFragment.create("__pycache__"); |
| |
| private static final FileType REQUIRES_INIT_PY = FileType.of(".py", ".so", ".pyc"); |
| |
| /** |
| * Used to get the set of empty __init__.py files to be added to a given set of files to allow the |
| * Python runtime to import subdirectories potentially containing Python code to be imported as |
| * packages. Ideally this feature goes away with --incompatible_default_to_explicit_init_py as the |
| * long term default behavior. |
| */ |
| public static class GetInitPyFiles implements Runfiles.EmptyFilesSupplier { |
| private final Predicate<PathFragment> isPackageInit; |
| |
| /** |
| * The Predicate isPackageInit's .test(source) should be true when a given source is known to be |
| * a valid __init__.py file equivalent, meaning no empty __init__.py file need be created. |
| * Useful for custom Python runtimes that may have non-standard Python package import logic. |
| */ |
| public GetInitPyFiles(Predicate<PathFragment> isPackageInit) { |
| this.isPackageInit = isPackageInit; |
| } |
| |
| @Override |
| public Set<PathFragment> getExtraPaths(Set<PathFragment> manifestPaths) { |
| return getInitPyFiles(manifestPaths); |
| } |
| |
| /** |
| * Returns the set of empty __init__.py(c) files to be added to a given set of files to allow |
| * the Python runtime to find the <code>.py</code> and <code>.so</code> files present in the |
| * tree. |
| */ |
| private ImmutableSet<PathFragment> getInitPyFiles(Set<PathFragment> manifestFiles) { |
| Set<PathFragment> result = new HashSet<>(); |
| // A set of directories that already have package init files. |
| Set<PathFragment> hasPackageInitDirs = new HashSet<>(); // For b/142135992. |
| |
| // Find directories containing Python package init files based on a caller supplied test in |
| // order to support non-standard Python package init naming schemes. |
| // This loop is done prior to the one below as we assume no order in the set and that we may |
| // find inits in parent directories listed after subdirectories which the nested loop below |
| // would need to know of. |
| for (PathFragment source : manifestFiles) { |
| if (isPackageInit.test(source)) { |
| hasPackageInitDirs.add(source.getParentDirectory()); |
| } |
| } |
| |
| for (PathFragment source : manifestFiles) { |
| // If we have a python or .so file at this level... |
| if (REQUIRES_INIT_PY.matches(source)) { |
| // ...then record that we need an __init__.py in this and all parents directories... |
| while (source.segmentCount() > 1) { |
| source = source.getParentDirectory(); |
| // ...unless it's a Python .pyc cache or we already have __init__ there. |
| if (!source.endsWith(PYCACHE) && !hasPackageInitDirs.contains(source)) { |
| PathFragment initpy = source.getRelative(INIT_PY); |
| PathFragment initpyc = source.getRelative(INIT_PYC); |
| |
| if (!manifestFiles.contains(initpy) && !manifestFiles.contains(initpyc)) { |
| result.add(initpy); |
| } |
| } |
| } |
| } |
| } |
| |
| return ImmutableSet.copyOf(result); |
| } |
| } // class GetInitPyFiles |
| |
| private PythonUtils() { |
| // This is a utility class, not to be instantiated. |
| } |
| |
| /** |
| * Get the artifact generated by the 2to3 action. |
| * |
| * <p>There might be conflicts eg. when the input file is generated, but that case is unsupported |
| * because 2to3 is obsolete. |
| * |
| * <p>Returns null and reports a rule error if the output file cannot be created because it is not |
| * underneath the target's package. |
| */ |
| @Nullable |
| private static Artifact get2to3OutputArtifact(RuleContext ruleContext, Artifact input) { |
| PathFragment rootRelativePath = input.getRootRelativePath(); |
| if (!rootRelativePath.startsWith(ruleContext.getPackageDirectory())) { |
| ruleContext.ruleError( |
| String.format( |
| "cannot perform 2to3 conversion on source file %s from another package", |
| rootRelativePath)); |
| return null; |
| } |
| ArtifactRoot root = |
| ruleContext.getConfiguration().getGenfilesDirectory(ruleContext.getRule().getRepository()); |
| return ruleContext.getDerivedArtifact(rootRelativePath, root); |
| } |
| |
| /** |
| * Creates an action for each Python 2 file to convert to Python 3. |
| * |
| * <p>Returns null and reports a rule error if an output file cannot be created. |
| */ |
| @Nullable |
| public static Map<PathFragment, Artifact> generate2to3Actions( |
| RuleContext ruleContext, Iterable<Artifact> inputs) { |
| // This creates many actions, but this is fine. Creating one action per library leads |
| // to some problems (when the same file is generated by two different actions), with |
| // little benefits and negligible memory improvement. |
| |
| Map<PathFragment, Artifact> symlinks = new HashMap<>(); |
| for (Artifact input : inputs) { |
| Artifact output = generate2to3Action(ruleContext, input); |
| if (output == null) { |
| return null; |
| } |
| symlinks.put(input.getRootRelativePath(), output); |
| } |
| return symlinks; |
| } |
| |
| /** |
| * Generates and registers one 2to3 action. |
| * |
| * <p>Returns null and reports an error if the output file cannot be created. |
| */ |
| @Nullable |
| private static Artifact generate2to3Action(RuleContext ruleContext, Artifact input) { |
| FilesToRunProvider py2to3converter = |
| ruleContext.getExecutablePrerequisite("$python2to3", TransitionMode.HOST); |
| Artifact output = get2to3OutputArtifact(ruleContext, input); |
| if (output == null) { |
| return null; |
| } |
| |
| CustomCommandLine.Builder commandLine = |
| CustomCommandLine.builder() |
| .add("--no-diffs") |
| .add("--nobackups") |
| .add("--write") |
| .addPath("--output-dir", output.getExecPath().getParentDirectory()) |
| .add("--write-unchanged-files") |
| .addExecPath(input); |
| |
| ruleContext.registerAction( |
| new SpawnAction.Builder() |
| .addInput(input) |
| .addOutput(output) |
| .setExecutable(py2to3converter) |
| .setProgressMessage("Converting to Python 3: %s", input.prettyPrint()) |
| .setMnemonic("2to3") |
| .addCommandLine(commandLine.build()) |
| .build(ruleContext)); |
| return output; |
| } |
| } |