Hardening cram, stratify uninstalls

projects/cram/src/python/cram/__main__.py

@@ -5,7 +5,6 @@ import logging
 import os
 from pathlib import Path
 import pickle
-import sys
 from typing import List
 
 from . import (
@@ -25,6 +24,11 @@ from vfs import Vfs
 log = logging.getLogger(__name__)
 
 
+def _exit(val):
+    logging.shutdown()
+    exit(val)
+
+
 def load(root: Path, name: str, clss):
     for c in clss:
         i = c(root, name)
@@ -33,10 +37,12 @@ def load(root: Path, name: str, clss):
 
 
 def load_package(root, name):
+    log.debug(f"Attempting to load package {name} from {root}")
     return load(root, name, [PackageV1, PackageV0])
 
 
 def load_profile(root, name):
+    log.debug(f"Attempting to load profile {name} from {root}")
     return load(root, name, [ProfileV1, ProfileV0])
 
     
@@ -44,6 +50,7 @@ def load_packages(root: Path) -> dict:
     """Load the configured packages."""
 
     packages = {}
+    log.debug(f"Trying to load packages from {root}...")
     for p in (root / "packages.d").glob("*"):
         name = str(p.relative_to(root))
         packages[name] = load_package(p, name)
@@ -71,14 +78,20 @@ def build_fs(root: Path, dest: Path, prelude: List[str]) -> Vfs:
     requirements = []
     requirements.extend(prelude)
 
+    if packages:
+        for p in packages:
+            log.debug(f"Loaded package {p}")
+    else:
+        log.warning("Loaded no packages!")
+
     for r in requirements:
         try:
             for d in packages[r].requires():
                 if d not in requirements:
                     requirements.append(d)
         except KeyError:
-            print(f"Error: Unable to load package {r}", file=sys.stderr)
-            exit(1)
+            log.fatal(f"Error: Unable to load package {r}")
+            _exit(1)
 
     # Compute the topsort graph
     requirements = {r: packages[r].requires() for r in requirements}
@@ -140,16 +153,21 @@ def scrub(old_fs: Vfs, new_fs: Vfs) -> Vfs:
 
     old_fs = old_fs.copy()
     new_fs = new_fs.copy()
+    cleanup_fs = Vfs([])
 
     # Look for files in the old log which are no longer present in the new log
     for txn in old_fs._log:
         if txn[0] == "link" and txn not in new_fs._log:
-            new_fs.unlink(txn[2])
+            cleanup_fs.unlink(txn[2])
 
         elif txn[0] == "mkdir" and txn not in new_fs._log:
-            new_fs.unlink(txn[1])
+            cleanup_fs.unlink(txn[1])
 
-    return new_fs
+    # Do unlink operations before we do install operations.
+    # This works around being unable to finely straify uninstall operations over their source packages.
+    cleanup_fs.merge(new_fs)
+
+    return cleanup_fs
 
 
 @click.group()
@@ -186,11 +204,19 @@ def do_apply(confdir, destdir, state_file, execute, optimize, require, exec_idem
     # Resolve the two input paths to absolutes
     root = confdir.resolve()
     dest = destdir.resolve()
+
+    if not root.is_dir():
+        log.fatal(f"{confdir} does not exist!")
+        _exit(1)
+
     if not state_file.is_absolute():
         state_file = root / state_file
 
-    new_fs = build_fs(root, dest, require)
     old_fs = load_state(state_file)
+    log.debug(f"Loaded old state consisting of {len(old_fs._log)} steps")
+
+    new_fs = build_fs(root, dest, require)
+    log.debug(f"Built new state consisting of {len(new_fs._log)} steps")
 
     # Middleware processing of the resulting filesystem(s)
     executable_fs = scrub(old_fs, new_fs)
@@ -219,7 +245,13 @@ def do_apply(confdir, destdir, state_file, execute, optimize, require, exec_idem
 @click.argument("list_packages", nargs=-1)
 def do_list(confdir, list_packages):
     """List out packages, profiles, hosts and subpackages in the <confdir>."""
-    packages = load_packages(confdir)
+    root = confdir.resolve()
+
+    if not root.is_dir():
+        log.fatal(f"{confdir} does not exist!")
+        _exit(1)
+
+    packages = load_packages(root)
 
     if list_packages:
         dest = Path("~/")
@@ -249,8 +281,14 @@ def do_list(confdir, list_packages):
 def do_state(confdir, state_file):
     """List out the last `apply` state in the <confdir>/.cram.log or --state-file."""
     root = confdir.resolve()
+
+    if not root.is_dir():
+        log.fatal(f"{confdir} does not exist!")
+        _exit(1)
+
     if not state_file.is_absolute():
         state_file = root / state_file
+
     fs = load_state(state_file)
     for e in fs._log:
         print(*e)

projects/cram/src/python/cram/common.py

@@ -38,7 +38,10 @@ def stow(fs: Vfs, src_dir: Path, dest_dir: Path, skip=[]):
             continue
 
         dest = dest_root / src.relative_to(src_root)
-        if src.is_dir():
+        if src.is_symlink():
+
+            fs.link(src.readlink().resolve(), dest)
+        elif src.is_dir():
             fs.mkdir(dest)
             fs.chmod(dest, src.stat().st_mode)
 

projects/cram/src/python/cram/v1.py

@@ -51,7 +51,12 @@ class PackageV1(Package):
             return any(self.do_sh_or_script(c, fs, dest) for c in content)
 
         elif isinstance(content, dict):
-            return self.do_sh_or_script(content["run"], fs, dest, {"cwd": self.root}.get(content.get("root"), "/tmp"))
+            return self.do_sh_or_script(
+                content["run"],
+                fs,
+                dest,
+                {"cwd": self.root}.get(content.get("root"), "/tmp")
+            )
 
         elif isinstance(content, str):
             sum = sha256()

projects/vfs/src/python/vfs/impl.py

@@ -79,3 +79,6 @@ class Vfs(object):
 
     def copy(self):
         return Vfs(list(self._log))
+
+    def merge(self, other: "Vfs"):
+        self._log.extend(other._log)