cache: generalize save and checkout

dvc/cache/base.py

@@ -115,7 +115,7 @@ def _filter_hash_info(self, hash_info, path_info, filter_info):
 
         return self._get_dir_info_hash(filtered_dir_info)[0]
 
-    def changed(self, path_info, hash_info, filter_info=None):
+    def changed(self, path_info, tree, hash_info, filter_info=None):
         """Checks if data has changed.
 
         A file is considered changed if:
@@ -138,7 +138,7 @@ def changed(self, path_info, hash_info, filter_info=None):
             "checking if '%s'('%s') has changed.", path_info, hash_info
         )
 
-        if not self.tree.exists(path):
+        if not tree.exists(path):
             logger.debug("'%s' doesn't exist.", path)
             return True
 
@@ -151,7 +151,7 @@ def changed(self, path_info, hash_info, filter_info=None):
             logger.debug("cache for '%s'('%s') has changed.", path, hi)
             return True
 
-        actual = self.tree.get_hash(path)
+        actual = tree.get_hash(path)
         if hi != actual:
             logger.debug(
                 "hash value '%s' for '%s' has changed (actual '%s').",
@@ -218,40 +218,25 @@ def _do_link(self, from_info, to_info, link_method):
             "Created '%s': %s -> %s", self.cache_types[0], from_info, to_info,
         )
 
-    def _save_file(self, path_info, tree, hash_info, save_link=True, **kwargs):
+    def _save_file(self, path_info, tree, hash_info, **kwargs):
         assert hash_info
 
         cache_info = self.tree.hash_to_path_info(hash_info.value)
-        if tree == self.tree:
-            if self.changed_cache(hash_info):
-                self.makedirs(cache_info.parent)
-                self.move(path_info, cache_info)
-                self.protect(cache_info)
-                self.link(cache_info, path_info)
-            elif self.tree.iscopy(path_info) and self._cache_is_copy(
-                path_info
-            ):
-                # Default relink procedure involves unneeded copy
-                self.unprotect(path_info)
+        if self.changed_cache(hash_info):
+            # using our makedirs to create dirs with proper permissions
+            self.makedirs(cache_info.parent)
+            if isinstance(tree, type(self.tree)):
+                self.tree.move(path_info, cache_info)
             else:
-                self.tree.remove(path_info)
-                self.link(cache_info, path_info)
-
-            if save_link:
-                self.tree.state.save_link(path_info)
-            # we need to update path and cache, since in case of reflink,
-            # or copy cache type moving original file results in updates on
-            # next executed command, which causes md5 recalculation
-            self.tree.state.save(path_info, hash_info)
-        else:
-            if self.changed_cache(hash_info):
                 with tree.open(path_info, mode="rb") as fobj:
                     self.tree.upload_fobj(fobj, cache_info)
-                callback = kwargs.get("download_callback")
-                if callback:
-                    callback(1)
+                tree.state.save(path_info, hash_info)
+            self.protect(cache_info)
+            self.tree.state.save(cache_info, hash_info)
 
-        self.tree.state.save(cache_info, hash_info)
+            callback = kwargs.get("download_callback")
+            if callback:
+                callback(1)
 
     def _transfer_file(self, from_tree, from_info):
         from dvc.utils import tmp_fname
@@ -399,13 +384,7 @@ def save_dir_info(self, dir_info, hash_info=None):
         return hi
 
     def _save_dir(
-        self,
-        path_info,
-        tree,
-        hash_info,
-        save_link=True,
-        filter_info=None,
-        **kwargs,
+        self, path_info, tree, hash_info, filter_info=None, **kwargs,
     ):
         if not hash_info.dir_info:
             hash_info.dir_info = tree.cache.get_dir_cache(hash_info)
@@ -418,20 +397,14 @@ def _save_dir(
             if filter_info and not entry_info.isin_or_eq(filter_info):
                 continue
 
-            self._save_file(
-                entry_info, tree, entry_hash, save_link=False, **kwargs
-            )
-
-        if save_link:
-            self.tree.state.save_link(path_info)
-        if self.tree.exists(path_info):
-            self.tree.state.save(path_info, hi)
+            self._save_file(entry_info, tree, entry_hash, **kwargs)
 
         cache_info = self.tree.hash_to_path_info(hi.value)
         self.tree.state.save(cache_info, hi)
+        tree.state.save(path_info, hi)
 
     @use_state
-    def save(self, path_info, tree, hash_info, save_link=True, **kwargs):
+    def save(self, path_info, tree, hash_info, **kwargs):
         if path_info.scheme != self.tree.scheme:
             raise RemoteActionNotImplemented(
                 f"save {path_info.scheme} -> {self.tree.scheme}",
@@ -447,17 +420,17 @@ def save(self, path_info, tree, hash_info, save_link=True, **kwargs):
                     errno.ENOENT, os.strerror(errno.ENOENT), path_info
                 )
 
-        self._save(path_info, tree, hash_info, save_link, **kwargs)
+        self._save(path_info, tree, hash_info, **kwargs)
         return hash_info
 
-    def _save(self, path_info, tree, hash_info, save_link=True, **kwargs):
+    def _save(self, path_info, tree, hash_info, **kwargs):
         to_info = self.tree.hash_to_path_info(hash_info.value)
         logger.debug("Saving '%s' to '%s'.", path_info, to_info)
 
         if tree.isdir(path_info):
-            self._save_dir(path_info, tree, hash_info, save_link, **kwargs)
+            self._save_dir(path_info, tree, hash_info, **kwargs)
         else:
-            self._save_file(path_info, tree, hash_info, save_link, **kwargs)
+            self._save_file(path_info, tree, hash_info, **kwargs)
 
     # Override to return path as a string instead of PathInfo for clouds
     # which support string paths (see local)
@@ -542,19 +515,19 @@ def changed_cache(self, hash_info, path_info=None, filter_info=None):
             )
         return self.changed_cache_file(hash_info)
 
-    def already_cached(self, path_info):
-        current = self.tree.get_hash(path_info)
+    def already_cached(self, path_info, tree):
+        current = tree.get_hash(path_info)
 
         if not current:
             return False
 
         return not self.changed_cache(current)
 
-    def safe_remove(self, path_info, force=False):
-        if not self.tree.exists(path_info):
+    def safe_remove(self, path_info, tree, force=False):
+        if not tree.exists(path_info):
             return
 
-        if not force and not self.already_cached(path_info):
+        if not force and not self.already_cached(path_info, tree):
             msg = (
                 "file '{}' is going to be removed."
                 " Are you sure you want to proceed?".format(str(path_info))
@@ -563,30 +536,48 @@ def safe_remove(self, path_info, force=False):
             if not prompt.confirm(msg):
                 raise ConfirmRemoveError(str(path_info))
 
-        self.tree.remove(path_info)
+        tree.remove(path_info)
 
     def _checkout_file(
-        self, path_info, hash_info, force, progress_callback=None, relink=False
+        self,
+        path_info,
+        tree,
+        hash_info,
+        force,
+        progress_callback=None,
+        relink=False,
     ):
         """The file is changed we need to checkout a new copy"""
-        added, modified = True, False
         cache_info = self.tree.hash_to_path_info(hash_info.value)
-        if self.tree.exists(path_info):
-            logger.debug("data '%s' will be replaced.", path_info)
-            self.safe_remove(path_info, force=force)
-            added, modified = False, True
-
-        self.link(cache_info, path_info)
-        self.tree.state.save_link(path_info)
-        self.tree.state.save(path_info, hash_info)
+        if tree.exists(path_info):
+            added = False
+
+            if not relink and self.changed(path_info, tree, hash_info):
+                modified = True
+                self.safe_remove(path_info, tree, force=force)
+                self.link(cache_info, path_info)
+            else:
+                modified = False
+
+                if tree.iscopy(path_info) and self._cache_is_copy(path_info):
+                    self.unprotect(path_info)
+                else:
+                    self.safe_remove(path_info, tree, force=force)
+                    self.link(cache_info, path_info)
+        else:
+            self.link(cache_info, path_info)
+            added, modified = True, False
+
+        tree.state.save(path_info, hash_info)
         if progress_callback:
             progress_callback(str(path_info))
 
-        return added, modified and not relink
+        return added, modified
 
     def _checkout_dir(
         self,
         path_info,
+        tree,
         hash_info,
         force,
         progress_callback=None,
@@ -596,7 +587,7 @@ def _checkout_dir(
         added, modified = False, False
         # Create dir separately so that dir is created
         # even if there are no files in it
-        if not self.tree.exists(path_info):
+        if not tree.exists(path_info):
             added = True
             self.makedirs(path_info)
 
@@ -605,46 +596,45 @@ def _checkout_dir(
         logger.debug("Linking directory '%s'.", path_info)
 
         for entry_info, entry_hash_info in dir_info.items(path_info):
-            entry_cache_info = self.tree.hash_to_path_info(
-                entry_hash_info.value
-            )
-
             if filter_info and not entry_info.isin_or_eq(filter_info):
                 continue
 
-            if relink or self.changed(entry_info, entry_hash_info):
+            entry_added, entry_modified = self._checkout_file(
+                entry_info,
+                tree,
+                entry_hash_info,
+                force,
+                progress_callback,
+                relink,
+            )
+            if entry_added or entry_modified:
                 modified = True
-                self.safe_remove(entry_info, force=force)
-                self.link(entry_cache_info, entry_info)
-                self.tree.state.save(entry_info, entry_hash_info)
-            if progress_callback:
-                progress_callback(str(entry_info))
 
         modified = (
-            self._remove_redundant_files(path_info, dir_info, force)
+            self._remove_redundant_files(path_info, tree, dir_info, force)
             or modified
         )
 
-        self.tree.state.save_link(path_info)
-        self.tree.state.save(path_info, hash_info)
+        tree.state.save(path_info, hash_info)
 
         # relink is not modified, assume it as nochange
         return added, not added and modified and not relink
 
-    def _remove_redundant_files(self, path_info, dir_info, force):
-        existing_files = set(self.tree.walk_files(path_info))
+    def _remove_redundant_files(self, path_info, tree, dir_info, force):
+        existing_files = set(tree.walk_files(path_info))
 
         needed_files = {info for info, _ in dir_info.items(path_info)}
         redundant_files = existing_files - needed_files
         for path in redundant_files:
-            self.safe_remove(path, force)
+            self.safe_remove(path, tree, force)
 
         return bool(redundant_files)
 
     @use_state
     def checkout(
         self,
         path_info,
+        tree,
         hash_info,
         force=False,
         progress_callback=None,
@@ -663,11 +653,11 @@ def checkout(
                     "No file hash info found for '%s'. It won't be created.",
                     path_info,
                 )
-            self.safe_remove(path_info, force=force)
+            self.safe_remove(path_info, tree, force=force)
             failed = path_info
 
         elif not relink and not self.changed(
-            path_info, hash_info, filter_info=filter_info
+            path_info, tree, hash_info, filter_info=filter_info
         ):
             logger.trace("Data '%s' didn't change.", path_info)
             skip = True
@@ -681,7 +671,7 @@ def checkout(
                     hash_info,
                     path_info,
                 )
-            self.safe_remove(path_info, force=force)
+            self.safe_remove(path_info, tree, force=force)
             failed = path_info
 
         if failed or skip:
@@ -702,6 +692,7 @@ def checkout(
 
         return self._checkout(
             path_info,
+            tree,
             hash_info,
             force,
             progress_callback,
@@ -712,20 +703,31 @@ def checkout(
     def _checkout(
         self,
         path_info,
+        tree,
         hash_info,
         force=False,
         progress_callback=None,
         relink=False,
         filter_info=None,
     ):
         if not hash_info.isdir:
-            return self._checkout_file(
-                path_info, hash_info, force, progress_callback, relink
+            ret = self._checkout_file(
+                path_info, tree, hash_info, force, progress_callback, relink
+            )
+        else:
+            ret = self._checkout_dir(
+                path_info,
+                tree,
+                hash_info,
+                force,
+                progress_callback,
+                relink,
+                filter_info,
             )
 
-        return self._checkout_dir(
-            path_info, hash_info, force, progress_callback, relink, filter_info
-        )
+        tree.state.save_link(path_info)
+
+        return ret
 
     def get_files_number(self, path_info, hash_info, filter_info):
         from funcy.py3 import ilen

dvc/cache/local.py

@@ -81,10 +81,10 @@ def hashes_exist(
             )
         ]
 
-    def already_cached(self, path_info):
+    def already_cached(self, path_info, tree):
         assert path_info.scheme in ["", "local"]
 
-        return super().already_cached(path_info)
+        return super().already_cached(path_info, tree)
 
     def _verify_link(self, path_info, link_type):
         if link_type == "hardlink" and self.tree.getsize(path_info) == 0:

dvc/dependency/repo.py

@@ -84,7 +84,7 @@ def download(self, to, jobs=None):
                 follow_subrepos=False,
             )
 
-        cache.checkout(to.path_info, hash_info)
+        cache.checkout(to.path_info, to.tree, hash_info)
 
     def update(self, rev=None):
         if rev: