Add pip3_import to run pip with python 3.

python/pip.bzl

@@ -13,7 +13,7 @@
 # limitations under the License.
 """Import pip requirements into Bazel."""
 
-def _pip_import_impl(repository_ctx):
+def _shared_pip_import_impl(python_interpreter, repository_ctx):
   """Core implementation of pip_import."""
 
   # Add an empty top-level BUILD file.
@@ -24,7 +24,8 @@ def _pip_import_impl(repository_ctx):
 
   # To see the output, pass: quiet=False
   result = repository_ctx.execute([
-    "python", repository_ctx.path(repository_ctx.attr._script),
+    python_interpreter, repository_ctx.path(repository_ctx.attr._script),
+    "--python_interpreter", python_interpreter,
     "--name", repository_ctx.attr.name,
     "--input", repository_ctx.path(repository_ctx.attr.requirements),
     "--output", repository_ctx.path("requirements.bzl"),
@@ -34,22 +35,43 @@ def _pip_import_impl(repository_ctx):
   if result.return_code:
     fail("pip_import failed: %s (%s)" % (result.stdout, result.stderr))
 
+_shared_attrs = {
+    "requirements": attr.label(
+        allow_files = True,
+        mandatory = True,
+        single_file = True,
+    ),
+    "_script": attr.label(
+        executable = True,
+        default = Label("//tools:piptool.par"),
+        cfg = "host",
+    ),
+}
+
+def _pip_import_impl(repository_ctx):
+    _shared_pip_import_impl("python", repository_ctx)
+
 pip_import = repository_rule(
-    attrs = {
-        "requirements": attr.label(
-            allow_files = True,
-            mandatory = True,
-            single_file = True,
-        ),
-        "_script": attr.label(
-            executable = True,
-            default = Label("//tools:piptool.par"),
-            cfg = "host",
-        ),
-    },
+    attrs = _shared_attrs,
     implementation = _pip_import_impl,
 )
 
+def _pip2_import_impl(repository_ctx):
+    _shared_pip_import_impl("python2", repository_ctx)
+
+pip2_import = repository_rule(
+    attrs = _shared_attrs,
+    implementation = _pip2_import_impl,
+)
+
+def _pip3_import_impl(repository_ctx):
+    _shared_pip_import_impl("python3", repository_ctx)
+
+pip3_import = repository_rule(
+    attrs = _shared_attrs,
+    implementation = _pip3_import_impl,
+)
+
 """A rule for importing <code>requirements.txt</code> dependencies into Bazel.
 
 This rule imports a <code>requirements.txt</code> file and generates a new

python/whl.bzl

@@ -17,7 +17,7 @@ def _whl_impl(repository_ctx):
   """Core implementation of whl_library."""
 
   args = [
-    "python",
+    repository_ctx.attr.python_interpreter,
     repository_ctx.path(repository_ctx.attr._script),
     "--whl", repository_ctx.path(repository_ctx.attr.whl),
     "--requirements", repository_ctx.attr.requirements,
@@ -35,6 +35,7 @@ def _whl_impl(repository_ctx):
 
 whl_library = repository_rule(
     attrs = {
+        "python_interpreter": attr.string(),
         "whl": attr.label(
             allow_files = True,
             mandatory = True,

rules_python/piptool.py

@@ -84,6 +84,9 @@ def pip_main(argv):
 parser = argparse.ArgumentParser(
     description='Import Python dependencies into Bazel.')
 
+parser.add_argument('--python_interpreter', action='store',
+                    help=('The python python interpreter to use '))
+
 parser.add_argument('--name', action='store',
                     help=('The namespace of the import.'))
 
@@ -175,10 +178,12 @@ def whl_library(wheel):
   if "{repo_name}" not in native.existing_rules():
     whl_library(
         name = "{repo_name}",
+        python_interpreter = "{python_interpreter}",
         whl = "@{name}//:{path}",
         requirements = "@{name}//:requirements.bzl",
         extras = [{extras}]
     )""".format(name=args.name, repo_name=wheel.repository_name(),
+                python_interpreter=args.python_interpreter,
                 path=wheel.basename(),
                 extras=','.join([
                   '"%s"' % extra