getdeps: add env subcommand

Summary:
X-link: facebookincubator/zstrong#1025

Add getdeps.py `env` subcommand to get the environment from getdeps in a sourcable form so that its easier to run/test/debug the binaries

There is an existing `debug` subcommand, but it starts an interactive shell inside getdeps, which isn't so useful for programatic use.

To get the output clean enough to source I switched getdeps print() logging to go to stderr.

example usage:
```
$ (source <(./build/fbcode_builder/getdeps.py --allow-system-packages env mononoke_integration); which mononoke)
```

Reviewed By: jdelliot

Differential Revision: D64982397

fbshipit-source-id: 65212936d42185e4d395557b56d3dba499caa128

Author: ahornby

build/fbcode_builder/getdeps.py

@@ -923,6 +923,27 @@ def run_project_cmd(self, args, loader, manifest):
         self.create_builder(loader, manifest).debug(reconfigure=False)
 
 
+@cmd(
+    "env",
+    "print the environment in a shell sourceable format",
+)
+class EnvCmd(ProjectCmdBase):
+    def setup_project_cmd_parser(self, parser):
+        parser.add_argument(
+            "--os-type",
+            help="Filter to just this OS type to run",
+            choices=["linux", "darwin", "windows"],
+            action="store",
+            dest="ostype",
+            default=None,
+        )
+
+    def run_project_cmd(self, args, loader, manifest):
+        if args.ostype:
+            loader.build_opts.host_type.ostype = args.ostype
+        self.create_builder(loader, manifest).printenv(reconfigure=False)
+
+
 @cmd("generate-github-actions", "generate a GitHub actions configuration")
 class GenerateGitHubActionsCmd(ProjectCmdBase):
     RUN_ON_ALL = """ [push, pull_request]"""

build/fbcode_builder/getdeps/builder.py

@@ -15,6 +15,7 @@
 import subprocess
 import sys
 import typing
+from shlex import quote as shellquote
 from typing import Optional
 
 from .dyndeps import create_dyn_dep_munger
@@ -157,6 +158,29 @@ def debug(self, reconfigure: bool) -> None:
         shell = ["powershell.exe"] if sys.platform == "win32" else ["/bin/sh", "-i"]
         self._run_cmd(shell, cwd=self.build_dir, env=env)
 
+    def printenv(self, reconfigure: bool) -> None:
+        """print the environment in a shell sourcable format"""
+        reconfigure = self._reconfigure(reconfigure)
+        self._apply_patchfile()
+        self._prepare(reconfigure=reconfigure)
+        env = self._compute_env(env=Env(src={}))
+        prefix = "export "
+        sep = ":"
+        expand = "$"
+        expandpost = ""
+        if self.build_opts.is_windows():
+            prefix = "SET "
+            sep = ";"
+            expand = "%"
+            expandpost = "%"
+        for k, v in sorted(env.items()):
+            existing = os.environ.get(k, None)
+            if k.endswith("PATH") and existing:
+                v = shellquote(v) + sep + f"{expand}{k}{expandpost}"
+            else:
+                v = shellquote(v)
+            print("%s%s=%s" % (prefix, k, v))
+
     def build(self, reconfigure: bool) -> None:
         print("Building %s..." % self.manifest.name)
         reconfigure = self._reconfigure(reconfigure)
@@ -225,14 +249,16 @@ def _build(self, reconfigure) -> None:
         system needs to regenerate its rules."""
         pass
 
-    def _compute_env(self):
+    def _compute_env(self, env=None) -> Env:
+        if env is None:
+            env = self.env
         # CMAKE_PREFIX_PATH is only respected when passed through the
         # environment, so we construct an appropriate path to pass down
         return self.build_opts.compute_env_for_install_dirs(
             self.loader,
             self.dep_manifests,
             self.ctx,
-            env=self.env,
+            env=env,
             manifest=self.manifest,
         )
 

build/fbcode_builder/getdeps/cargo.py

@@ -9,6 +9,7 @@
 import os
 import re
 import shutil
+import sys
 import typing
 
 from .builder import BuilderBase
@@ -97,7 +98,7 @@ def _create_cargo_config(self):
 
         if os.path.isfile(cargo_config_file):
             with open(cargo_config_file, "r") as f:
-                print(f"Reading {cargo_config_file}")
+                print(f"Reading {cargo_config_file}", file=sys.stderr)
                 cargo_content = f.read()
         else:
             cargo_content = ""
@@ -142,7 +143,8 @@ def _create_cargo_config(self):
         if new_content != cargo_content:
             with open(cargo_config_file, "w") as f:
                 print(
-                    f"Writing cargo config for {self.manifest.name} to {cargo_config_file}"
+                    f"Writing cargo config for {self.manifest.name} to {cargo_config_file}",
+                    file=sys.stderr,
                 )
                 f.write(new_content)
 
@@ -270,7 +272,10 @@ def _patchup_workspace(self, dep_to_git) -> None:
             new_content += "\n".join(config)
             if new_content != manifest_content:
                 with open(patch_cargo, "w") as f:
-                    print(f"writing patch to {patch_cargo}")
+                    print(
+                        f"writing patch to {patch_cargo}",
+                        file=sys.stderr,
+                    )
                     f.write(new_content)
 
     def _resolve_config(self, dep_to_git) -> typing.Dict[str, typing.Dict[str, str]]:
@@ -296,7 +301,8 @@ def _resolve_config(self, dep_to_git) -> typing.Dict[str, typing.Dict[str, str]]
                     if c in crate_source_map and c not in crates_to_patch_path:
                         crates_to_patch_path[c] = crate_source_map[c]
                         print(
-                            f"{self.manifest.name}: Patching crate {c} via virtual manifest in {self.workspace_dir()}"
+                            f"{self.manifest.name}: Patching crate {c} via virtual manifest in {self.workspace_dir()}",
+                            file=sys.stderr,
                         )
                 if crates_to_patch_path:
                     git_url_to_crates_and_paths[git_url] = crates_to_patch_path
@@ -352,7 +358,8 @@ def _resolve_dep_to_git(self):
                             subpath = subpath.replace("/", "\\")
                         crate_path = os.path.join(dep_source_dir, subpath)
                         print(
-                            f"{self.manifest.name}: Mapped crate {crate} to dep {dep} dir {crate_path}"
+                            f"{self.manifest.name}: Mapped crate {crate} to dep {dep} dir {crate_path}",
+                            file=sys.stderr,
                         )
                         crate_source_map[crate] = crate_path
             elif dep_cargo_conf:
@@ -367,7 +374,8 @@ def _resolve_dep_to_git(self):
                                 crate = match.group(1)
                                 if crate:
                                     print(
-                                        f"{self.manifest.name}: Discovered crate {crate} in dep {dep} dir {crate_root}"
+                                        f"{self.manifest.name}: Discovered crate {crate} in dep {dep} dir {crate_root}",
+                                        file=sys.stderr,
                                     )
                                     crate_source_map[crate] = crate_root
 
@@ -414,7 +422,8 @@ def _resolve_dep_to_crates(self, build_source_dir, dep_to_git):
                         for c in crates:
                             if c not in existing_crates:
                                 print(
-                                    f"Patch {self.manifest.name} uses {dep_name} crate {crates}"
+                                    f"Patch {self.manifest.name} uses {dep_name} crate {crates}",
+                                    file=sys.stderr,
                                 )
                                 existing_crates.add(c)
                         dep_to_crates.setdefault(name, set()).update(existing_crates)

build/fbcode_builder/getdeps/manifest.py

@@ -8,6 +8,7 @@
 import configparser
 import io
 import os
+import sys
 from typing import List
 
 from .builder import (
@@ -391,7 +392,10 @@ def _is_satisfied_by_preinstalled_environment(self, ctx):
             return False
         for key in envs:
             val = os.environ.get(key, None)
-            print(f"Testing ENV[{key}]: {repr(val)}")
+            print(
+                f"Testing ENV[{key}]: {repr(val)}",
+                file=sys.stderr,
+            )
             if val is None:
                 return False
             if len(val) == 0:

build/fbcode_builder/getdeps/runcmd.py

@@ -10,16 +10,12 @@
 import subprocess
 import sys
 
+from shlex import quote as shellquote
+
 from .envfuncs import Env
 from .platform import is_windows
 
 
-try:
-    from shlex import quote as shellquote
-except ImportError:
-    from pipes import quote as shellquote
-
-
 class RunCommandError(Exception):
     pass