1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
|
# 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, Dict)
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_("typespec") - ident('name') + LBRACE + Dict( ZeroOrMore( Group(ident + EQ + integer + SEMI) ))('values') + 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;
}"""
parser.runTests([test1, test2])
|