[elbe-devel] [PATCH 2/5] rpcaptcache: Make download_source better

[Olivier Dion]

The method used to download the source package from a binary package
description.  This is changed in order to be able to download source
packages that are not reference by the binary packages cache.

A reverse lookup has been tried before without much success and
python-apt lacks of any such binding.  Thus, will do what fetch_source
used to do, but without passing from any binary packages.

Signed-off-by: Olivier Dion <dion at linutronix.de>
---
 elbepack/rpcaptcache.py | 67 ++++++++++++++++++++++++++++++++++-------
 1 file changed, 56 insertions(+), 11 deletions(-)

diff --git a/elbepack/rpcaptcache.py b/elbepack/rpcaptcache.py
index 14c3f654..847b41cd 100644
--- a/elbepack/rpcaptcache.py
+++ b/elbepack/rpcaptcache.py
@@ -16,8 +16,9 @@ import time
 from multiprocessing.util import Finalize
 from multiprocessing.managers import BaseManager
 
-from apt_pkg import config, version_compare, TagFile
+from apt_pkg import config, version_compare, TagFile, SourceRecords, Acquire, AcquireFile
 from apt import Cache
+from apt.package import FetchError
 
 from elbepack.aptprogress import (ElbeAcquireProgress, ElbeInstallProgress,
                                   ElbeOpProgress)
@@ -333,17 +334,61 @@ class RPCAPTCache(InChRootObject):
                                     ElbeAcquireProgress())
         return self.rfs.fname(rel_filename)
 
-    def download_source(self, pkgname, path, version=None):
-        p = self.cache[pkgname]
-        if version is None:
-            pkgver = p.installed
-        else:
-            pkgver = p.versions[version]
+    def download_source(self, src_name, src_version, dest_dir):
+
+        allow_untrusted = config.find_b("APT::Get::AllowUnauthenticated",
+                                        False)
+
+        rec = SourceRecords()
+        acq = Acquire(ElbeAcquireProgress())
+
+        # poorman's iterator
+        while True:
+            next_p = rec.lookup(src_name)
+            # End of the list?
+            if not next_p:
+                raise ("No source found for %s_%s" % (src_name, src_version))
+            if src_version == rec.version:
+                break
+
+        # We don't allow untrusted package and the package is not
+        # marks as trusted
+        if not (allow_untrusted or rec.index.is_trusted):
+            raise FetchError("Can't fetch source %s_%s; Source %r is not trusted" %
+                             (src_name, src_version, rec.index.describe))
+
+        # Copy from src to dst all files of the source package
+        dsc = None
+        files = []
+        for _file in rec.files:
+            src = os.path.basename(_file.path)
+            dst = os.path.join(dest_dir, src)
+
+            if 'dsc' ==  _file.type:
+                dsc = dst
+
+            if not (allow_untrusted or _file.hashes.usable):
+                raise FetchError("Can't fetch file %s. No trusted hash found." % dst)
+
+            # acq is accumlating the AcquireFile, the files list only
+            # exists to prevent Python from GC the object .. I guess.
+            # Anyway, if we don't keep the list, We will get an empty
+            # directory
+            files.append(AcquireFile(acq, rec.index.archive_uri(_file.path),
+                                     _file.hashes, _file.size, src, destfile=dst))
+        acq.run()
+
+        if dsc is None:
+            raise ValueError("No source found for %s_%s" %
+                             (src_name, src_version))
+
+        for item in acq.items:
+            if item.STAT_DONE != item.status:
+                raise FetchError("Can't fetch item %s: %s" %
+                                  (item.destfile, item.error_text))
+
+        return self.rfs.fname(os.path.abspath(dsc))
 
-        rel_filename = pkgver.fetch_source(path,
-                                           ElbeAcquireProgress(),
-                                           unpack=False)
-        return self.rfs.fname(rel_filename)
 
 def get_rpcaptcache(rfs, arch,
                     notifier=None, norecommend=False, noauth=True):
-- 
2.26.2