1 files changed, 103 insertions, 0 deletions
diff --git a/src/examples/protobuf_parser.py b/src/examples/protobuf_parser.py
new file mode 100644
index 0000000..8940e14
--- /dev/null
+++ b/src/examples/protobuf_parser.py
@@ -0,0 +1,103 @@
+# protobuf_parser.py
+#
+#  simple parser for parsing protobuf .proto files
+#
+#  Copyright 2010, Paul McGuire
+#
+
+from pyparsing import (Word, alphas, alphanums, Regex, Suppress, Forward,
+    Group, oneOf, ZeroOrMore, Optional, delimitedList, Keyword,
+    restOfLine, quotedString)
+
+ident = Word(alphas+"_",alphanums+"_").setName("identifier")
+integer = Regex(r"[+-]?\d+")
+
+LBRACE,RBRACE,LBRACK,RBRACK,LPAR,RPAR,EQ,SEMI = map(Suppress,"{}[]()=;")
+
+kwds = """message required optional repeated enum extensions extends extend 
+          to package service rpc returns true false option import"""
+for kw in kwds.split():
+    exec("%s_ = Keyword('%s')" % (kw.upper(), kw))
+
+messageBody = Forward()
+
+messageDefn = MESSAGE_ - ident("messageId") + LBRACE + messageBody("body") + RBRACE
+
+typespec = oneOf("""double float int32 int64 uint32 uint64 sint32 sint64 
+                    fixed32 fixed64 sfixed32 sfixed64 bool string bytes""") | ident
+rvalue = integer | TRUE_ | FALSE_ | ident
+fieldDirective = LBRACK + Group(ident + EQ + rvalue) + RBRACK
+fieldDefn = (( REQUIRED_ | OPTIONAL_ | REPEATED_ )("fieldQualifier") - 
+              typespec("typespec") + ident("ident") + EQ + integer("fieldint") + ZeroOrMore(fieldDirective) + SEMI)
+
+# enumDefn ::= 'enum' ident '{' { ident '=' integer ';' }* '}'
+enumDefn = ENUM_ - ident + LBRACE + ZeroOrMore( Group(ident + EQ + integer + SEMI) ) + RBRACE
+
+# extensionsDefn ::= 'extensions' integer 'to' integer ';'
+extensionsDefn = EXTENSIONS_ - integer + TO_ + integer + SEMI
+
+# messageExtension ::= 'extend' ident '{' messageBody '}'
+messageExtension = EXTEND_ - ident + LBRACE + messageBody + RBRACE
+
+# messageBody ::= { fieldDefn | enumDefn | messageDefn | extensionsDefn | messageExtension }*
+messageBody << Group(ZeroOrMore( Group(fieldDefn | enumDefn | messageDefn | extensionsDefn | messageExtension) ))
+
+# methodDefn ::= 'rpc' ident '(' [ ident ] ')' 'returns' '(' [ ident ] ')' ';'
+methodDefn = (RPC_ - ident("methodName") + 
+              LPAR + Optional(ident("methodParam")) + RPAR + 
+              RETURNS_ + LPAR + Optional(ident("methodReturn")) + RPAR)
+
+# serviceDefn ::= 'service' ident '{' methodDefn* '}'
+serviceDefn = SERVICE_ - ident("serviceName") + LBRACE + ZeroOrMore(Group(methodDefn)) + RBRACE
+
+# packageDirective ::= 'package' ident [ '.' ident]* ';'
+packageDirective = Group(PACKAGE_ - delimitedList(ident, '.', combine=True) + SEMI)
+
+comment = '//' + restOfLine
+
+importDirective = IMPORT_ - quotedString("importFileSpec") + SEMI
+
+optionDirective = OPTION_ - ident("optionName") + EQ + quotedString("optionValue") + SEMI
+
+topLevelStatement = Group(messageDefn | messageExtension | enumDefn | serviceDefn | importDirective | optionDirective)
+
+parser = Optional(packageDirective) + ZeroOrMore(topLevelStatement)
+
+parser.ignore(comment)
+
+
+test1 = """message Person { 
+  required int32 id = 1; 
+  required string name = 2; 
+  optional string email = 3; 
+}"""
+
+test2 = """package tutorial;
+
+message Person {
+  required string name = 1;
+  required int32 id = 2;
+  optional string email = 3;
+
+  enum PhoneType {
+    MOBILE = 0;
+    HOME = 1;
+    WORK = 2;
+  }
+
+  message PhoneNumber {
+    required string number = 1;
+    optional PhoneType type = 2 [default = HOME];
+  }
+
+  repeated PhoneNumber phone = 4;
+}
+
+message AddressBook {
+  repeated Person person = 1;
+}"""
+
+from pprint import pprint
+#~ print parser.parseString(test2, parseAll=True).dump()
+pprint( parser.parseString(test2, parseAll=True).asList())
+