push/pull: naively transfer run cache (#3746)

This is the most simple (aka dumb) implementation for this
functionality that is needed to unblock CICD development.

dvc/command/data_sync.py

@@ -32,6 +32,7 @@ class CmdDataPull(CmdDataBase):
                 with_deps=self.args.with_deps,
                 force=self.args.force,
                 recursive=self.args.recursive,
+                run_cache=self.args.run_cache,
             )
             self.log_summary(stats)
         except (CheckoutError, DvcException) as exc:
@@ -54,6 +55,7 @@ class CmdDataPush(CmdDataBase):
                 all_commits=self.args.all_commits,
                 with_deps=self.args.with_deps,
                 recursive=self.args.recursive,
+                run_cache=self.args.run_cache,
             )
             self.log_summary({"pushed": processed_files_count})
         except DvcException:
@@ -74,6 +76,7 @@ class CmdDataFetch(CmdDataBase):
                 all_commits=self.args.all_commits,
                 with_deps=self.args.with_deps,
                 recursive=self.args.recursive,
+                run_cache=self.args.run_cache,
             )
             self.log_summary({"fetched": processed_files_count})
         except DvcException:
@@ -163,6 +166,12 @@ def add_parser(subparsers, _parent_parser):
         default=False,
         help="Pull cache for subdirectories of the specified directory.",
     )
+    pull_parser.add_argument(
+        "--run-cache",
+        action="store_true",
+        default=False,
+        help=argparse.SUPPRESS,
+    )
     pull_parser.set_defaults(func=CmdDataPull)
 
     # Push
@@ -212,6 +221,12 @@ def add_parser(subparsers, _parent_parser):
         default=False,
         help="Push cache for subdirectories of specified directory.",
     )
+    push_parser.add_argument(
+        "--run-cache",
+        action="store_true",
+        default=False,
+        help=argparse.SUPPRESS,
+    )
     push_parser.set_defaults(func=CmdDataPush)
 
     # Fetch
@@ -267,6 +282,12 @@ def add_parser(subparsers, _parent_parser):
         default=False,
         help="Fetch cache for subdirectories of specified directory.",
     )
+    fetch_parser.add_argument(
+        "--run-cache",
+        action="store_true",
+        default=False,
+        help=argparse.SUPPRESS,
+    )
     fetch_parser.set_defaults(func=CmdDataFetch)
 
     # Status

dvc/data_cloud.py

@@ -47,7 +47,14 @@ class DataCloud(object):
     def _init_remote(self, name):
         return Remote(self.repo, name=name)
 
-    def push(self, cache, jobs=None, remote=None, show_checksums=False):
+    def push(
+        self,
+        cache,
+        jobs=None,
+        remote=None,
+        show_checksums=False,
+        run_cache=False,
+    ):
         """Push data items in a cloud-agnostic way.
 
         Args:
@@ -58,14 +65,23 @@ class DataCloud(object):
             show_checksums (bool): show checksums instead of file names in
                 information messages.
         """
+        remote = self.get_remote(remote, "push")
+
+        if run_cache:
+            self.repo.stage_cache.push(remote)
+
         return self.repo.cache.local.push(
-            cache,
-            jobs=jobs,
-            remote=self.get_remote(remote, "push"),
-            show_checksums=show_checksums,
+            cache, jobs=jobs, remote=remote, show_checksums=show_checksums,
         )
 
-    def pull(self, cache, jobs=None, remote=None, show_checksums=False):
+    def pull(
+        self,
+        cache,
+        jobs=None,
+        remote=None,
+        show_checksums=False,
+        run_cache=False,
+    ):
         """Pull data items in a cloud-agnostic way.
 
         Args:
@@ -77,6 +93,10 @@ class DataCloud(object):
                 information messages.
         """
         remote = self.get_remote(remote, "pull")
+
+        if run_cache:
+            self.repo.stage_cache.pull(remote)
+
         downloaded_items_num = self.repo.cache.local.pull(
             cache, jobs=jobs, remote=remote, show_checksums=show_checksums
         )

dvc/repo/__init__.py

@@ -106,7 +106,7 @@ class Repo(object):
         self.cache = Cache(self)
         self.cloud = DataCloud(self)
 
-        self.stage_cache = StageCache(self.cache.local.cache_dir)
+        self.stage_cache = StageCache(self)
 
         self.metrics = Metrics(self)
         self.params = Params(self)

dvc/repo/fetch.py

@@ -20,6 +20,7 @@ def _fetch(
     all_tags=False,
     recursive=False,
     all_commits=False,
+    run_cache=False,
 ):
     """Download data items from a cloud and imported repositories
 
@@ -50,7 +51,11 @@ def _fetch(
 
     try:
         downloaded += self.cloud.pull(
-            used, jobs, remote=remote, show_checksums=show_checksums
+            used,
+            jobs,
+            remote=remote,
+            show_checksums=show_checksums,
+            run_cache=run_cache,
         )
     except NoRemoteError:
         if not used.external and used["local"]:

dvc/repo/pull.py

@@ -17,6 +17,7 @@ def pull(
     force=False,
     recursive=False,
     all_commits=False,
+    run_cache=False,
 ):
     processed_files_count = self._fetch(
         targets,
@@ -27,6 +28,7 @@ def pull(
         all_commits=all_commits,
         with_deps=with_deps,
         recursive=recursive,
+        run_cache=run_cache,
     )
     stats = self._checkout(
         targets=targets, with_deps=with_deps, force=force, recursive=recursive

dvc/repo/push.py

@@ -12,6 +12,7 @@ def push(
     all_tags=False,
     recursive=False,
     all_commits=False,
+    run_cache=False,
 ):
     used = self.used_cache(
         targets,
@@ -24,4 +25,5 @@ def push(
         jobs=jobs,
         recursive=recursive,
     )
-    return self.cloud.push(used, jobs, remote=remote)
+
+    return self.cloud.push(used, jobs, remote=remote, run_cache=run_cache)

dvc/stage/cache.py

@@ -2,6 +2,7 @@ import logging
 import os
 
 import yaml
+from funcy import first
 from voluptuous import Invalid
 
 from dvc.schema import COMPILED_LOCK_FILE_STAGE_SCHEMA
@@ -36,8 +37,9 @@ def _get_stage_hash(stage):
 
 
 class StageCache:
-    def __init__(self, cache_dir):
-        self.cache_dir = os.path.join(cache_dir, "runs")
+    def __init__(self, repo):
+        self.repo = repo
+        self.cache_dir = os.path.join(repo.cache.local.cache_dir, "runs")
 
     def _get_cache_dir(self, key):
         return os.path.join(self.cache_dir, key[:2], key)
@@ -101,3 +103,24 @@ class StageCache:
         if not cache:
             return
         StageLoader.fill_from_lock(stage, cache)
+
+    @staticmethod
+    def _transfer(func, from_remote, to_remote):
+        runs = from_remote.path_info / "runs"
+        if not from_remote.exists(runs):
+            return
+
+        for src in from_remote.walk_files(runs):
+            rel = src.relative_to(from_remote.path_info)
+            dst = to_remote.path_info / rel
+            key = dst.parent
+            # check if any build cache already exists for this key
+            if to_remote.exists(key) and first(to_remote.walk_files(key)):
+                continue
+            func(src, dst)
+
+    def push(self, remote):
+        return self._transfer(remote.upload, self.repo.cache.local, remote)
+
+    def pull(self, remote):
+        return self._transfer(remote.download, remote, self.repo.cache.local)

tests/func/test_data_cloud.py

@@ -826,6 +826,8 @@ def test_pipeline_file_target_ops(tmp_dir, dvc, local_remote, run_copy):
 
     outs = ["foo", "bar", "lorem", "ipsum", "baz", "lorem2"]
 
+    remove(dvc.stage_cache.cache_dir)
+
     dvc.push()
     # each one's a copy of other, hence 3
     assert len(recurse_list_dir(fspath_py35(local_remote))) == 3

tests/unit/command/test_data_sync.py

@@ -17,6 +17,7 @@ def test_fetch(mocker):
             "--all-commits",
             "--with-deps",
             "--recursive",
+            "--run-cache",
         ]
     )
     assert cli_args.func == CmdDataFetch
@@ -35,6 +36,7 @@ def test_fetch(mocker):
         all_commits=True,
         with_deps=True,
         recursive=True,
+        run_cache=True,
     )
 
 
@@ -54,6 +56,7 @@ def test_pull(mocker):
             "--with-deps",
             "--force",
             "--recursive",
+            "--run-cache",
         ]
     )
     assert cli_args.func == CmdDataPull
@@ -73,6 +76,7 @@ def test_pull(mocker):
         with_deps=True,
         force=True,
         recursive=True,
+        run_cache=True,
     )
 
 
@@ -91,6 +95,7 @@ def test_push(mocker):
             "--all-commits",
             "--with-deps",
             "--recursive",
+            "--run-cache",
         ]
     )
     assert cli_args.func == CmdDataPush
@@ -109,4 +114,5 @@ def test_push(mocker):
         all_commits=True,
         with_deps=True,
         recursive=True,
+        run_cache=True,
     )