add srclib spec parser

fdroidserver/common.py

@@ -63,7 +63,7 @@ import fdroidserver.metadata
 import fdroidserver.lint
 from fdroidserver import _
 from fdroidserver.exception import FDroidException, VCSException, NoSubmodulesException,\
-    BuildException, VerificationException
+    BuildException, VerificationException, MetaDataException
 from .asynchronousfilereader import AsynchronousFileReader
 
 # The path to this fdroidserver distribution
@@ -1808,6 +1808,36 @@ def get_app_from_url(url):
     return app
 
 
+def parse_srclib_spec(spec):
+
+    if type(spec) != str:
+        raise MetaDataException(_("can not parse scrlib spec "
+                                  "(not a string): '{}'")
+                                .format(spec))
+
+    tokens = spec.split('@')
+    if len(tokens) > 2:
+        raise MetaDataException(_("could not parse srclib spec "
+                                  "(too many '@' signs): '{}'")
+                                .format(spec))
+    elif len(tokens) < 2:
+        raise MetaDataException(_("could not parse srclib spec "
+                                  "(no ref specified): '{}'")
+                                .format(spec))
+
+    name = tokens[0]
+    ref = tokens[1]
+    number = None
+    subdir = None
+
+    if ':' in name:
+        number, name = name.split(':', 1)
+    if '/' in name:
+        name, subdir = name.split('/', 1)
+
+    return (name, ref, number, subdir)
+
+
 def getsrclib(spec, srclib_dir, subdir=None, basepath=False,
               raw=False, prepare=True, preponly=False, refresh=True,
               build=None):