use pyyaml for rewriting .yml metadata files

This replaces the broken, custom code with the standard YAML lib.

In rewritemeta, do not call app.metadatapath since it will be deleted when
the dict is cleaned up for outputing. metadatapath is only used internally
and should not be written out.

closes #169
refs #290

fdroidserver/metadata.py

@@ -239,8 +239,9 @@ build_flags_order = [
     'novcheck',
 ]
 
-
-build_flags = set(build_flags_order + ['versionName', 'versionCode'])
+# old .txt format has version name/code inline in the 'Build:' line
+# but YAML and JSON have a explicit key for them
+build_flags = ['versionName', 'versionCode'] + build_flags_order
 
 
 class Build(dict):
@@ -959,6 +960,25 @@ def parse_yaml_metadata(mf, app):
     return app
 
 
+def write_yaml(mf, app):
+
+    def _class_as_dict_representer(dumper, data):
+        '''Creates a YAML representation of a App/Build instance'''
+        return dumper.represent_dict(data)
+
+    empty_keys = [k for k, v in app.items() if not v]
+    for k in empty_keys:
+        del app[k]
+
+    for k in ['added', 'lastUpdated', 'id', 'metadatapath']:
+        if k in app:
+            del app[k]
+
+    yaml.add_representer(fdroidserver.metadata.App, _class_as_dict_representer)
+    yaml.add_representer(fdroidserver.metadata.Build, _class_as_dict_representer)
+    yaml.dump(app, mf, default_flow_style=False)
+
+
 build_line_sep = re.compile(r'(?<!\\),')
 build_cont = re.compile(r'^[ \t]')
 
@@ -1304,70 +1324,6 @@ def write_txt(mf, app):
     write_plaintext_metadata(mf, app, w_comment, w_field, w_build)
 
 
-def write_yaml(mf, app):
-
-    def w_comment(line):
-        mf.write("# %s\n" % line)
-
-    def escape(v):
-        if not v:
-            return ''
-        if any(c in v for c in [': ', '%', '@', '*']):
-            return "'" + v.replace("'", "''") + "'"
-        return v
-
-    def w_field(f, v, prefix='', t=None):
-        if t is None:
-            t = fieldtype(f)
-        v = ''
-        if t == TYPE_LIST:
-            v = '\n'
-            for e in v:
-                v += prefix + ' - ' + escape(e) + '\n'
-        elif t == TYPE_MULTILINE:
-            v = ' |\n'
-            for l in v.splitlines():
-                if l:
-                    v += prefix + '  ' + l + '\n'
-                else:
-                    v += '\n'
-        elif t == TYPE_BOOL:
-            v = ' yes\n'
-        elif t == TYPE_SCRIPT:
-            cmds = [s + '&& \\' for s in v.split('&& ')]
-            if len(cmds) > 0:
-                cmds[-1] = cmds[-1][:-len('&& \\')]
-            w_field(f, cmds, prefix, 'multiline')
-            return
-        else:
-            v = ' ' + escape(v) + '\n'
-
-        mf.write(prefix)
-        mf.write(f)
-        mf.write(":")
-        mf.write(v)
-
-    global first_build
-    first_build = True
-
-    def w_build(build):
-        global first_build
-        if first_build:
-            mf.write("builds:\n")
-            first_build = False
-
-        w_field('versionName', build.versionName, '  - ', TYPE_STRING)
-        w_field('versionCode', build.versionCode, '    ', TYPE_STRING)
-        for f in build_flags_order:
-            v = build.get(f)
-            if not v:
-                continue
-
-            w_field(f, v, '    ', flagtype(f))
-
-    write_plaintext_metadata(mf, app, w_comment, w_field, w_build)
-
-
 def write_metadata(metadatapath, app):
     _, ext = fdroidserver.common.get_extension(metadatapath)
     accepted = fdroidserver.common.config['accepted_formats']

fdroidserver/rewritemeta.py

@@ -72,9 +72,10 @@ def main():
         parser.error("Unsupported metadata format, use: --to [" + ' '.join(supported) + "]")
 
     for appid, app in apps.items():
-        base, ext = common.get_extension(app.metadatapath)
+        path = app.metadatapath
+        base, ext = common.get_extension(path)
         if not options.to and ext not in supported:
-            logging.info("Ignoring %s file at '%s'" % (ext, app.metadatapath))
+            logging.info("Ignoring %s file at '%s'" % (ext, path))
             continue
 
         to_ext = ext
@@ -83,13 +84,24 @@ def main():
 
         if options.list:
             if not proper_format(app):
-                print(app.metadatapath)
+                print(path)
             continue
 
+        newbuilds = []
+        for build in app.builds:
+            new = metadata.Build()
+            for k in metadata.build_flags:
+                v = build[k]
+                if v is None or v is False or v == [] or v == '':
+                    continue
+                new[k] = v
+            newbuilds.append(new)
+        app.builds = newbuilds
+
         metadata.write_metadata(base + '.' + to_ext, app)
 
         if ext != to_ext:
-            os.remove(app.metadatapath)
+            os.remove(path)
 
     logging.debug("Finished.")