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
|
defmodule AzureEx.DSL do
@moduledoc false
@path_var_re ~r/\{([^\}]+)\}/
@api_version_query_re ~r/api\-version=(.+)$/
defmacro defendpoint(name, raw_api) do
# 解析并获取请求方法
method_s = raw_api |> String.split(" ") |> List.first() |> Macro.underscore()
# +1 是为了消除空格
uri_begin_pos = String.length(method_s) + 1
method = String.to_atom(method_s)
# 解析并获取 API 版本
[_, api_version] = Regex.run(@api_version_query_re, raw_api)
[{query_begin_pos, _}, _] = Regex.run(@api_version_query_re, raw_api, return: :index)
# 截断获取 URI
uri = String.slice(raw_api, uri_begin_pos..(query_begin_pos - 2))
# 扫描 URI 中的路径变量
r = Regex.scan(@path_var_re, uri)
# 处理并得到路径变量的名称列表
path_vars =
r
|> Enum.map(&List.last/1)
|> Enum.map(&Macro.underscore/1)
# 路径变量列表对应的参数 AST
path_var_args_ast =
path_vars
|> Enum.map(fn var_name -> {String.to_atom(var_name), [], Elixir} end)
# 函数签名 AST
fun_sign_ast = {
String.to_atom(Macro.underscore(name)),
[],
path_var_args_ast ++ [{:\\, [], [{:options, [], Elixir}, []]}]
}
# 使用变量分割 URI
raw_segments = Regex.split(@path_var_re, uri)
unless length(raw_segments) == length(path_vars) + 1 do
raise """
Error parsing raw URI, wrong number of path variables.\n
URI: #{uri}
Vars: #{inspect(path_vars)}
"""
end
# <<>> 宏的参数 AST
splicing_args_ast =
raw_segments
|> Enum.with_index()
|> Enum.reduce([], fn {seg, i}, acc ->
acc = acc ++ [seg]
if var = Enum.at(path_vars, i) do
var_ast =
{:"::", [],
[
{{:., [], [Kernel, :to_string]}, [], [{String.to_atom(var), [], Elixir}]},
{:binary, [], Elixir}
]}
acc ++ [var_ast]
else
acc
end
end)
# <<>> 宏的调用 AST
splicing_call_ast = {:<<>>, [], splicing_args_ast}
quote do
def unquote(fun_sign_ast) do
api_version =
Keyword.get(unquote({:options, [], Elixir}), :"api-version", unquote(api_version))
params = Keyword.get(unquote({:options, [], Elixir}), :params)
data = Keyword.get(unquote({:options, [], Elixir}), :data)
endpoint = unquote(splicing_call_ast) <> "?" <> "api-version=#{api_version}"
endpoint =
if params do
endpoint <> "&#{URI.encode_query(params)}"
else
endpoint
end
AzureEx.Request.call(endpoint, unquote(method), data)
end
end
end
end
|
