Windows support and exposing interpreters

README.md

@@ -55,11 +55,24 @@ pyenv_install(
 )
 ```
 
+## Windows
+
+If you want to use ```rules_pyenv``` on Windows you should [enable symlinks](https://docs.bazel.build/versions/master/windows.html#enable-symlink-support)
+
+## Using the interpreter in repository rules
+
+The interpreters are exposed as files, so you can refer to them in a repository rule.
+
+You can refer to the ```python2``` interpreter as ```@pyenv//:py2/python``` and to the ```python3``` interpreter as ```@pyenv//:py3/python```.
+
+## Build problems
+
+```pyenv``` is building Python from sources, so you need all things necessary to build Python. If you have any problems regarding this, you should see [this page](https://github.com/pyenv/pyenv/wiki/common-build-problems) first.
+
 ## Caveats
 
 - This thing needs tests
 - This thing needs build automation
-- This thing hasn't been tried on Windows (yet); hence tests and build automation
 - You will probably find bugs. No, you're not crazy, it's just not working right; open an issue (PRs are welcome too)
 - Since the native Bazel rules only support CPython your use of `pyenv` is restricted to CPython versions 2 and 3. If
     you want additional support for other Python impl

pyenv/defs.bzl

@@ -1,21 +1,51 @@
 load("@bazel_tools//tools/build_defs/repo:utils.bzl", "maybe")
 
+DEFAULT_REPOSITORY_NAME = "pyenv"
+PY2_DEFAULT_DIR_NAME = "py2"
+PY3_DEFAULT_DIR_NAME = "py3"
+INTERPRETER_DEFAULT_NAME = "python"
+
+CONFIGURATIONS = {
+    "windows": {
+        "pyenv_dir": "bin",
+        "executable": "pyenv.bat",
+        "versions_dir": "versions",
+        "options": ["-q"],
+        "interpreter_dir": "",
+        "interpreter": "python.exe"
+    },
+    "unix": {
+        "pyenv_dir": "bin",
+        "executable": "pyenv",
+        "versions_dir": "versions",
+        "options": [],
+        "interpreter_dir": "bin",
+        "interpreter": "python"
+    }
+}
+
 BUILD_FILE_CONTENT = """# This file was automatically generated by @dpu_rules_pyenv//pyenv:defs.bzl
 package(default_visibility = ["//visibility:public"])
 
 load("@bazel_tools//tools/python:toolchain.bzl", "py_runtime_pair")
 
+# export interpreter so it can accessed as a regular file
+exports_files([
+    "{py2_dir_link}/{interpreter}",
+    "{py3_dir_link}/{interpreter}"
+])
+
 py_runtime(
     name = "python_{py2}_runtime",
     files = glob(["versions/{py2}/**/*"], exclude_directories = 0),
-    interpreter = "versions/{py2}/bin/python",
+    interpreter = "versions/{py2}/{interpreter_path}",
     python_version = "PY2"
 )
 
 py_runtime(
     name = "python_{py3}_runtime",
     files = glob(["versions/{py3}/**/*"], exclude_directories = 0),
-    interpreter = "versions/{py3}/bin/python",
+    interpreter = "versions/{py3}/{interpreter_path}",
     python_version = "PY3"
 )
 
@@ -32,27 +62,30 @@ toolchain(
 )
 """
 
+def _is_windows(repository_ctx):
+    """Returns true when os is recognized as windows
+    Args:
+      repository_ctx: The repository rule context
+    """
+    os_family = repository_ctx.os.name.lower()
+    return os_family.find("windows") != -1
+
+def _get_config(repository_ctx):
+    return CONFIGURATIONS["windows"] if _is_windows(repository_ctx) else CONFIGURATIONS["unix"]
+
 def _download_pyenv(repository_ctx):
     """Used to download a pyenv version.
     Args:
       repository_ctx: The repository rule context
     """
 
-    pyenv_version = repository_ctx.attr._pyenv_version
-    pyenv_repositories = repository_ctx.attr._pyenv_repositories
-    os_family = "unix" if repository_ctx.os.name.lower().find("windows") == -1 else "windows"
-    version_os = "%s-%s" % (pyenv_version, os_family)
-
-    if version_os in pyenv_repositories:
-        url, strip_prefix, sha256 = pyenv_repositories[version_os]
-    else:
-        fail("Unknown pyenv version %s" % pyenv_version)
+    pyenv_repo = repository_ctx.attr.pyenv_win_repo if _is_windows(repository_ctx) else repository_ctx.attr.pyenv_repo
 
     repository_ctx.download_and_extract(
-        url = [url],
+        url = pyenv_repo["url"],
         output = "./",
-        stripPrefix = strip_prefix,
-        sha256 = sha256,
+        stripPrefix = pyenv_repo["strip_prefix"],
+        sha256 = pyenv_repo["sha256"],
     )
 
 def _setup_pyenv(repository_ctx):
@@ -70,73 +103,106 @@ def _setup_pyenv(repository_ctx):
         if not pyenv_root:
             fail("Unable to find PYENV_ROOT")
 
-        repository_ctx.symlink(pyenv_path, "bin/pyenv")
-        repository_ctx.symlink("{pyenv_root}/versions".format(pyenv_root = pyenv_root), "versions")
+        pyenv_dir = _get_config(repository_ctx)["pyenv_dir"]
+        executable =  _get_config(repository_ctx)["executable"]
+        versions_dir = _get_config(repository_ctx)["versions_dir"]
+
+        repository_ctx.symlink(pyenv_path, 
+                               "{}/{}".format(pyenv_dir, executable))
+        repository_ctx.symlink("{}/{}".format(pyenv_root, versions_dir), 
+                               versions_dir)
 
 def _install_python(repository_ctx, version):
     if not version.startswith("2") and not version.startswith("3"):
         fail("pyenv_install currently only supports cpython major versions 2 and 3")
 
     repository_ctx.report_progress("Installing Python %s" % version)
-    pyenv_root = repository_ctx.path("./bin/pyenv").realpath.dirname.dirname
-    res = repository_ctx.execute(["bin/pyenv", "install", "-s", version], environment = {"PYENV_ROOT": str(pyenv_root)})
+
+    pyenv_dir = _get_config(repository_ctx)["pyenv_dir"]
+    executable =  _get_config(repository_ctx)["executable"]
+    options =  _get_config(repository_ctx)["options"]
+
+    pyenv_path = "./{}/{}".format(pyenv_dir, executable)
+    pyenv_root = repository_ctx.path(pyenv_path).realpath.dirname.dirname
+    # install in current directory, so intepreter can be accessed by "versions/..."
+    res = repository_ctx.execute(["bin/{}".format(executable), "install"] + options + [version], 
+                                 environment = {"PYENV_ROOT": str(pyenv_root)})
 
     if res.return_code:
         fail("pyenv failed to install version %s" % version + res.stdout + res.stderr)
 
-def _setup_build_file(repository_ctx, py2, py3):
+def _setup_links(repository_ctx, version, dir_name):
+    interpreter_dir = _get_config(repository_ctx)["interpreter_dir"]
+    versions_dir = _get_config(repository_ctx)["versions_dir"]
+    bindir = "{}/{}".format(versions_dir, version) + ("/{}".format(interpreter_dir) if interpreter_dir else "")
+
+    # create symlink to bin directory for easier access by users
+    repository_ctx.symlink(bindir, dir_name)
+
+    # on windows interpreter is 'python.exe', so create a symlink to it and name it 'python', so it can be accessed the same way on windows and unix
+    interpreter = _get_config(repository_ctx)["interpreter"]
+    if interpreter != INTERPRETER_DEFAULT_NAME:
+        repository_ctx.symlink("{}/{}".format(bindir, interpreter), "{}/{}".format(bindir, INTERPRETER_DEFAULT_NAME))
+
+def _setup_build_files(repository_ctx, py2, py3, py2_dir, py3_dir):
+    interpreter_dir = _get_config(repository_ctx)["interpreter_dir"]
+    interpreter_path = "{}/{}".format(interpreter_dir, INTERPRETER_DEFAULT_NAME) if interpreter_dir else INTERPRETER_DEFAULT_NAME
     repository_ctx.file(
-        "BUILD.bazel",
-        content = BUILD_FILE_CONTENT.format(py2 = py2, py3 = py3),
+        "BUILD",
+        content = BUILD_FILE_CONTENT.format(py2 = py2, 
+                                            py3 = py3, 
+                                            py2_dir_link = py2_dir, 
+                                            py3_dir_link = py3_dir,
+                                            interpreter = INTERPRETER_DEFAULT_NAME,
+                                            interpreter_path = interpreter_path)
     )
 
 def _pyenv_install_impl(repository_ctx):
-    py2 = repository_ctx.attr.py2_version
-    py3 = repository_ctx.attr.py3_version
+    py2 = repository_ctx.attr.py2
+    py3 = repository_ctx.attr.py3
+    py2_dir = repository_ctx.attr.py2_dir
+    py3_dir = repository_ctx.attr.py3_dir
 
     _setup_pyenv(repository_ctx)
     _install_python(repository_ctx, py2)
     _install_python(repository_ctx, py3)
-    _setup_build_file(repository_ctx, py2, py3)
+    _setup_links(repository_ctx, py2, py2_dir)
+    _setup_links(repository_ctx, py3, py3_dir)
+    _setup_build_files(repository_ctx, py2, py3, py2_dir, py3_dir)
 
 _pyenv_install = repository_rule(
     _pyenv_install_impl,
     attrs = {
-        "py2_version": attr.string(mandatory = True),
-        "py3_version": attr.string(mandatory = True),
-        "hermetic": attr.bool(mandatory = True),
-        # NOTE: Users may care about these private attributes at some point
-        "_pyenv_version": attr.string(
-            default = "1.2",
-        ),
-        "_pyenv_repositories": attr.string_list_dict(
-            default = {
-                "1.2-unix": (
-                    "https://github.com/pyenv/pyenv/archive/v1.2.18.tar.gz",
-                    "pyenv-1.2.18",
-                    "cc147f020178bb2f1ce0a8b9acb0bdf73979d967ce7d7415e22746e84e0eec7a",
-                ),
-                "1.2-windows": (
-                    "https://github.com/pyenv-win/pyenv-win/archive/v1.2.4.tar.gz",
-                    "pyenv-win-1.2.4",
-                    "0f3d3851eb692335c443a54700ffd99f0066f51c3b94ab0a867174c83f749554",
-                ),
-            },
-        ),
-    },
+        "py2": attr.string(mandatory = True, doc = "exact version of python2"),
+        "py3": attr.string(mandatory = True, doc = "exact version of python3"),
+        "py2_dir": attr.string(mandatory = True, doc = "directory for python2"),
+        "py3_dir": attr.string(mandatory = True, doc = "directory for python3"),
+        "hermetic": attr.bool(default = True, doc = "True if pyenv should be downloaded, False if local pyenv should be used"),
+        "pyenv_repo": attr.string_dict(default = {
+            "url": "https://github.com/pyenv/pyenv/archive/v1.2.18.tar.gz",
+            "strip_prefix": "pyenv-1.2.18",
+            "sha256": "cc147f020178bb2f1ce0a8b9acb0bdf73979d967ce7d7415e22746e84e0eec7a"
+        }, doc = "unix pyenv repository"),
+        "pyenv_win_repo": attr.string_dict(default = {
+            "url": "https://github.com/pyenv-win/pyenv-win/archive/v2.64.3.tar.gz",
+            "strip_prefix": "pyenv-win-2.64.3/pyenv-win",
+            "sha256": "9894fed264fb29e4aaff29728bea3c6f1c2d0106128fa8bbf17949f722d510d9"
+        }, doc = "windows pyenv repository")
+    }
 )
 
-def pyenv_install(py2, py3, hermetic = True):
+def pyenv_install(py2, py3, py2_dir = PY2_DEFAULT_DIR_NAME, py3_dir = PY3_DEFAULT_DIR_NAME, name = DEFAULT_REPOSITORY_NAME, **kwargs):
     """
     Macro to install and register a py_runtime_pair.
     """
 
     maybe(
         _pyenv_install,
-        name = "pyenv",
-        py2_version = py2,
-        py3_version = py3,
-        hermetic = hermetic,
+        name = name,
+        py2 = py2,
+        py3 = py3,
+        py2_dir = py2_dir,
+        py3_dir = py3_dir
     )
 
-    native.register_toolchains("@pyenv//:python_toolchain")
+    native.register_toolchains("@{}//:python_toolchain".format(name))