Add stamping to .deb package version and description

pkg/private/deb/deb.bzl

@@ -17,6 +17,7 @@ load("//pkg:providers.bzl", "PackageArtifactInfo", "PackageVariablesInfo")
 load("//pkg/private:util.bzl", "setup_output_files")
 
 _tar_filetype = [".tar", ".tar.gz", ".tgz", ".tar.bz2", "tar.xz"]
+_stamp_condition = Label("//pkg/private:private_stamp_detect")
 
 def _pkg_deb_impl(ctx):
     """The implementation for the pkg_deb rule."""
@@ -107,6 +108,12 @@ def _pkg_deb_impl(ctx):
     else:
         fail("Neither description_file nor description attribute was specified")
 
+    # Files for stamping variables
+    if ctx.attr.private_stamp_detect:
+        args += ["--stamp=@" + ctx.version_file.path]
+        args += ["--stamp=@" + ctx.info_file.path]
+        files += [ctx.version_file, ctx.info_file]
+
     # Built using can also be specified by a file or inlined (but is not mandatory)
     if ctx.attr.built_using_file:
         if ctx.attr.built_using:
@@ -344,6 +351,10 @@ See https://www.debian.org/doc/debian-policy/ch-files.html#s-config-files.""",
             providers = [PackageVariablesInfo],
         ),
 
+        # Is --stamp set on the command line?
+        # TODO(https://github.com/bazelbuild/rules_pkg/issues/340): Remove this.
+        "private_stamp_detect": attr.bool(default = False),
+
         # Implicit dependencies.
         "_make_deb": attr.label(
             default = Label("//pkg/private/deb:make_deb"),
@@ -362,5 +373,9 @@ def pkg_deb(name, out = None, **kwargs):
     pkg_deb_impl(
         name = name,
         out = out,
+        private_stamp_detect = select({
+            _stamp_condition: True,
+            "//conditions:default": False,
+        }),
         **kwargs
     )

pkg/private/deb/make_deb.py

@@ -348,6 +348,10 @@ def main():
   parser.add_argument(
       '--triggers',
       help='The triggers file (prefix with @ to provide a path).')
+  parser.add_argument(
+      '--stamp',
+      action='append',
+      help='The stamp variables (prefix with @ to provide a path).')
   # see
   # https://www.debian.org/doc/manuals/debian-faq/ch-pkg_basics.en.html#s-conffile
   parser.add_argument(
@@ -356,6 +360,11 @@ def main():
   AddControlFlags(parser)
   options = parser.parse_args()
 
+  stamp = dict()
+  if options.stamp:
+      for stamp_vars in options.stamp:
+          stamp.update(helpers.ParseStamp(helpers.GetFlagValue(stamp_vars)))
+
   CreateDeb(
       options.output,
       options.data,
@@ -368,8 +377,8 @@ def main():
       triggers=helpers.GetFlagValue(options.triggers, False),
       conffiles=GetFlagValues(options.conffile),
       package=options.package,
-      version=helpers.GetFlagValue(options.version),
-      description=helpers.GetFlagValue(options.description),
+      version=helpers.GetFlagValue(options.version, stamp=stamp),
+      description=helpers.GetFlagValue(options.description, stamp=stamp),
       maintainer=helpers.GetFlagValue(options.maintainer),
       section=options.section,
       architecture=helpers.GetFlagValue(options.architecture),
@@ -393,7 +402,7 @@ def main():
       architecture=options.architecture,
       description=helpers.GetFlagValue(options.description),
       maintainer=helpers.GetFlagValue(options.maintainer), package=options.package,
-      version=helpers.GetFlagValue(options.version), section=options.section,
+      version=helpers.GetFlagValue(options.version, stamp=stamp), section=options.section,
       priority=options.priority, distribution=options.distribution,
       urgency=options.urgency)
 

pkg/private/helpers.py

@@ -12,6 +12,7 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 import os
+import re
 import sys
 
 def SplitNameValuePairAtSeparator(arg, sep):
@@ -48,7 +49,7 @@ def SplitNameValuePairAtSeparator(arg, sep):
   # if we leave the loop, the character sep was not found unquoted
   return (head, '')
 
-def GetFlagValue(flagvalue, strip=True):
+def GetFlagValue(flagvalue, strip=True, stamp=None):
   """Converts a raw flag string to a useable value.
 
   1. Expand @filename style flags to the content of filename.
@@ -63,6 +64,7 @@ def GetFlagValue(flagvalue, strip=True):
   Args:
     flagvalue: (str) raw flag value
     strip: (bool) Strip white space.
+    stamp: (dict) Stamp variables for inline values
 
   Returns:
     Python2: unicode
@@ -84,6 +86,17 @@ def GetFlagValue(flagvalue, strip=True):
       if sys.version_info[0] > 2:
         flagvalue = os.fsencode(flagvalue).decode('utf-8')
 
+    if stamp != None:
+      flagvalue = re.sub(r'\{(\w+)\}', lambda m: stamp.get(m.group(1), m.group(0)), flagvalue)
+
     if strip:
       return flagvalue.strip()
   return flagvalue
+
+def ParseStamp(data):
+  vars = dict()
+  for line in data.split("\n"):
+    sep = line.find(' ')
+    if sep >= 0:
+      vars[line[:sep]] = line[sep+1:]
+  return vars