aboutsummaryrefslogtreecommitdiff
path: root/src/guff/api-handler.cr
blob: ad7870630bb2a6907870017ec05bdc1a3ca91a07 (plain)
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
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
require "json"
require "./handler"
require "./api-methods"

private macro define_method_calls(hash)
  case namespace
  {% for namespace, methods in hash %}
    when "{{ namespace.id }}"
      case method
      {% for method in methods %}
        when "{{ method }}"
          do_{{ namespace.id }}_{{ method }}(context, get_method_args(
            context.request.query_params,
            "{{ namespace.id }}",
            "{{ method.id }}"
          ))
      {% end %}
      else
        raise "unknown method"
      end
  {% end %}
  else
    raise "unknown namespace"
  end
end

module Guff
  class APIHandler < Handler
    include APIMethods
    include APIContentType

    PATH_RE = %r{
      ^/api

      (?:
        # method call
        (?:
          /
          (?<namespace>[a-z0-9_-]+)
          /
          (?<method>[a-z0-9_]+)
        )

        |

        # index.html
        /(?:index(?:\.html|)|)

        |

        # implicit index (no trailing slash)
      )

      $
    }mx

    def call(context : HTTP::Server::Context)
      if md = (context.request.path || "").match(PATH_RE)
        if md["namespace"]?
          # method call
          do_call(context, md["namespace"], md["method"])
        else
          # api index
          do_docs(context)
        end
      else
        call_next(context)
      end
    end

    private def do_call(
      context   : HTTP::Server::Context,
      namespace : String,
      method    : String
    )
      # set response type
      context.response.content_type = get_content_type

      # method call
      json = begin
        #
        # macro expands to equivalent of the following for each
        # namespace and method:
        #
        #   args = get_method_args(context, namespace, method)
        #   send("do_#{namespace}_#{method}".intern, context, args)
        #
        define_method_calls({
          post: [
            get_posts,
          ],

          tag: [
            get_tags,
            remove_tags,
          ],

          test: [
            version,
            get_posts,
            error,
          ],
        })
      rescue e
        { "error": e.to_s }.to_json
      end

      # send body
      context.response.puts json
    end

    private def do_docs(context : HTTP::Server::Context)
      APIDocsHTMLView.run(context)
    end
  end
end