From 73c493500b1a4d3c81ac854541e92ea385d02ccc Mon Sep 17 00:00:00 2001
From: Casper da Costa-Luis <casper.dcl@physics.org>
Date: Wed, 8 Sep 2021 07:09:52 +0100
Subject: [PATCH] remove `tpi.base` dependency (#6554)

* remove tpi.base dependency

* potential future-proof constructor
---
 dvc/machine/backend/base.py      | 31 +++++++++++++++++++++++++++----
 dvc/machine/backend/terraform.py |  8 +++++++-
 2 files changed, 34 insertions(+), 5 deletions(-)

diff --git a/dvc/machine/backend/base.py b/dvc/machine/backend/base.py
index 22ff27316..19ca7cdf0 100644
--- a/dvc/machine/backend/base.py
+++ b/dvc/machine/backend/base.py
@@ -1,15 +1,38 @@
-from abc import abstractmethod
+from abc import ABC, abstractmethod
 from contextlib import contextmanager
 from typing import TYPE_CHECKING, Iterator, Optional
 
-from tpi import base
-
 if TYPE_CHECKING:
     from dvc.fs.ssh import SSHFileSystem
     from dvc.repo.experiments.executor.base import BaseExecutor
+    from dvc.types import StrPath
 
 
-class BaseMachineBackend(base.BaseMachineBackend):
+class BaseMachineBackend(ABC):
+    def __init__(self, tmp_dir: "StrPath", **kwargs):
+        raise NotImplementedError
+
+    @abstractmethod
+    def create(self, name: Optional[str] = None, **config):
+        """Create and start an instance of the specified machine."""
+
+    @abstractmethod
+    def destroy(self, name: Optional[str] = None, **config):
+        """Stop and destroy all instances of the specified machine."""
+
+    @abstractmethod
+    def instances(
+        self, name: Optional[str] = None, **config
+    ) -> Iterator[dict]:
+        """Iterate over status of all instances of the specified machine."""
+
+    def close(self):
+        pass
+
+    @abstractmethod
+    def run_shell(self, name: Optional[str] = None, **config):
+        """Spawn an interactive SSH shell for the specified machine."""
+
     @abstractmethod
     def get_executor(
         self, name: Optional[str] = None, **config
diff --git a/dvc/machine/backend/terraform.py b/dvc/machine/backend/terraform.py
index 187b73313..118fb3512 100644
--- a/dvc/machine/backend/terraform.py
+++ b/dvc/machine/backend/terraform.py
@@ -5,11 +5,17 @@ from tpi import TerraformProviderIterative, terraform
 
 from dvc.fs.ssh import SSHFileSystem
 
+from .base import BaseMachineBackend
+
 if TYPE_CHECKING:
     from dvc.repo.experiments.executor.base import BaseExecutor
+    from dvc.types import StrPath
 
 
-class TerraformBackend(terraform.TerraformBackend):
+class TerraformBackend(terraform.TerraformBackend, BaseMachineBackend):
+    def __init__(self, tmp_dir: "StrPath", **kwargs):
+        super().__init__(tmp_dir)
+
     def get_executor(
         self, name: Optional[str] = None, **config
     ) -> "BaseExecutor":