Packages
kafka_protocol
1.0.0
4.3.4
4.3.3
4.3.2
4.3.1
4.3.0
4.2.9
4.2.8
4.2.7
4.2.6
4.2.5
4.2.4
4.2.3
4.2.2
4.2.1
4.2.0
4.1.10
4.1.9
4.1.8
4.1.7
4.1.6
4.1.5
4.1.4
4.1.3
4.1.2
4.1.1
4.1.0
4.0.3
4.0.2
4.0.1
3.0.1
3.0.0
2.4.1
2.3.6
2.3.5
2.3.4
2.3.3
2.3.2
2.3.1
2.3.0
2.2.9
2.2.8
2.2.7
2.2.6
2.2.5
2.2.4
2.2.3
2.2.2
2.2.1
2.2.0
2.1.2
2.1.1
2.1.0
2.0.1
2.0.0
1.1.3
1.1.2
1.1.1
1.1.0
1.0.0
0.9.2
0.9.1
0.9.0
0.8.0
0.7.8
0.7.7
0.7.6
0.7.5
0.7.4
0.7.3
0.7.2
0.7.1
0.7.0
0.6.0
0.4.0
0.3.2
0.3.1
0.2.3
Kafka protocol library for Erlang/Elixir
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priv/kpro_gen.escript
#!/usr/bin/env escript
%% -*- erlang -*-
%%%
%%% Copyright (c) 2014-2016, Klarna AB
%%%
%%% Licensed under the Apache License, Version 2.0 (the "License");
%%% you may not use this file except in compliance with the License.
%%% You may obtain a copy of the License at
%%%
%%% http://www.apache.org/licenses/LICENSE-2.0
%%%
%%% Unless required by applicable law or agreed to in writing, software
%%% distributed under the License is distributed on an "AS IS" BASIS,
%%% WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
%%% See the License for the specific language governing permissions and
%%% limitations under the License.
%%%
%% This script reads definitions of kafka data structures from priv/kafka.bnf
%% and generates:
%% src/kpro_schema.erl
-mode(compile).
-include("../include/kpro_private.hrl").
main(_Args) ->
ok = file:set_cwd(this_dir()),
{ok, _} = leex:file(kpro_scanner),
{ok, _} = compile:file(kpro_scanner, [report_errors]),
{ok, _} = yecc:file(kpro_parser),
{ok, _} = compile:file(kpro_parser, [report_errors]),
{ok, DefGroups} = kpro_parser:file("kafka.bnf"),
ExpandedTypes = [I || I <- lists:map(fun expand/1, DefGroups), is_tuple(I)],
GrouppedTypes = group_per_name(ExpandedTypes, []),
ok = generate_schema_module(GrouppedTypes).
-define(SCHEMA_MODULE_HEADER,"%% generated code, do not edit!
-module(kpro_schema).
-export([get/2]).
").
generate_schema_module(GrouppedTypes) ->
Filename = filename:join(["..", "src", "kpro_schema.erl"]),
Clauses = lists:flatmap(fun generate_schema_clauses/1, GrouppedTypes),
IoData =
[?SCHEMA_MODULE_HEADER,
"\n",
infix(Clauses, ";\n"),
".\n\n"
],
file:write_file(Filename, IoData).
generate_schema_clauses({Name, VersionedFields0}) ->
VersionedFields = lists:keysort(1, VersionedFields0),
generate_schema_clauses(Name, merge_versions(VersionedFields)).
generate_schema_clauses(_Name, []) -> [];
generate_schema_clauses(Name, [{Versions, Fields} | Rest]) ->
Head =
case Versions of
V when is_integer(V) ->
["get(", Name, ", ", integer_to_list(V), ") ->"];
[V | Vs] ->
MinV = integer_to_list(V),
MaxV = integer_to_list(lists:last(Vs)),
["get(", Name, ", V) when V >= ", MinV, ", V =< ", MaxV, " ->"]
end,
Body = io_lib:format(" ~p", [Fields]),
[ iolist_to_binary([Head, "\n", Body])
| generate_schema_clauses(Name, Rest)
].
group_per_name([], Acc) -> Acc;
group_per_name([ExpandedType | Rest], Acc) ->
{Name, Version, Fields} = split_name_version(ExpandedType),
AccumulatedVersions1 =
case lists:keyfind(Name, 1, Acc) of
false ->
[];
{_, AccumulatedVersions0} ->
AccumulatedVersions0
end,
AccumulatedVersions = [{Version, Fields} | AccumulatedVersions1],
NewAcc = lists:keystore(Name, 1, Acc, {Name, AccumulatedVersions}),
group_per_name(Rest, NewAcc).
merge_versions([]) -> [];
merge_versions([_] = L) -> L;
merge_versions([{V1, Fields1}, {V2, Fields2} | Rest]) ->
case Fields1 =:= Fields2 of
true ->
Versions = lists:flatten([V1, V2]),
merge_versions([{Versions, Fields1} | Rest]);
false ->
[{V1, Fields1} | merge_versions([{V2, Fields2} | Rest])]
end.
split_name_version({Tag, Fields}) ->
[Vsn, $v, $_ | NameReversed] =
lists:reverse(underscorize(atom_to_list(Tag))),
Name = lists:reverse(NameReversed),
Version = Vsn - $0,
{Name, Version, Fields}.
expand([{Tag, Fields} | Refs]) ->
{Tag, expand_fields(Fields, Refs)}.
expand_fields([], _Refs) -> [];
expand_fields([Name | Rest], Refs) when is_atom(Name) ->
{Name, Type0} = lists:keyfind(Name, 1, Refs),
Type = expand_type(Type0, Refs),
[{Name, Type} | expand_fields(Rest, Refs)];
expand_fields([{array, Name} | Rest], Refs) ->
{Name, Type0} = lists:keyfind(Name, 1, Refs),
Type = expand_type(Type0, Refs),
[{Name, {array, Type}} | expand_fields(Rest, Refs)].
expand_type(Type, _Refs) when ?IS_KAFKA_PRIMITIVE(Type) ->
Type;
expand_type(Fields, Refs) when is_list(Fields) ->
expand_fields(Fields, Refs).
this_dir() ->
ThisScript = escript:script_name(),
filename:dirname(ThisScript).
%% "FooBarV1" -> "foo_bar_v1"
underscorize([H | T]) ->
[ string:to_lower(H) |
lists:flatmap(
fun(C) ->
case $A =< C andalso C =< $Z of
true -> [$_, string:to_lower(C)];
false -> [C]
end
end, T)].
infix([], _Sep) -> [];
infix([Str], _Sep) -> [Str];
infix([H | T], Sep) -> [H, Sep | infix(T, Sep)].
%%% Local Variables:
%%% allout-layout: t
%%% erlang-indent-level: 2
%%% End: