Module: DeepUnrest::Read

Defined in:
lib/deep_unrest/read.rb

Class Method Summary collapse

Class Method Details

.create_read_mappings(params, user, addr = []) ⇒ Object 



5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
 
# File 'lib/deep_unrest/read.rb', line 5

def self.create_read_mappings(params, user, addr = [])
  return unless params

  params.map do |k, v|
    resource_addr = [*addr, k]
    uuid = SecureRandom.uuid
    v[:uuid] = uuid
    [{ klass: k.singularize.classify.constantize,
       policy: "#{k.singularize.classify}Policy".constantize,
       resource: "#{k.singularize.classify}Resource".constantize,
       scope_type: :index,
       addr: resource_addr,
       key: k.camelize(:lower),
       uuid: uuid,
       query: DeepUnrest.deep_underscore_keys(v) },
     *create_read_mappings(v[:include], user, [*resource_addr, :include])]
  end.flatten.compact
end

.execute_queries(ctx, mappings, parent_context = {}, included = [], meta = [], addr = []) ⇒ Object 



188
189
190
191
192
193
 
# File 'lib/deep_unrest/read.rb', line 188

def self.execute_queries(ctx, mappings, parent_context = {}, included = [], meta = [], addr = [])
  mappings.select { |m| m[:addr].size == 1 }.each do |item|
    item[:results] = execute_query(ctx, item, mappings, parent_context, included, meta, addr)
  end
  [included, meta]
end

.execute_query(ctx, item, mappings, parent_context, included, meta, addr, parent = nil) ⇒ Object 



180
181
182
183
184
185
186
 
# File 'lib/deep_unrest/read.rb', line 180

def self.execute_query(ctx, item, mappings, parent_context, included, meta, addr, parent = nil)
  if get_query_type(item) == :list
    query_list(ctx, item, mappings, parent_context, included, meta, addr, parent)
  else
    query_item(ctx, item, mappings, parent_context, included, meta, addr, parent)
  end
end

.format_processor_results(resource_klass, processor_result) ⇒ Object 



105
106
107
108
 
# File 'lib/deep_unrest/read.rb', line 105

def self.format_processor_results(resource_klass, processor_result)
  results = processor_result.resource_set.resource_klasses[resource_klass] || {}
  results.values.map {|r| r[:resource] }
end

.format_response(mappings) ⇒ Object 



195
196
197
198
199
200
201
 
# File 'lib/deep_unrest/read.rb', line 195

def self.format_response(mappings)
  response = {}
  mappings.each do |mapping|
    DeepUnrest.set_attr(response, mapping[:addr], mapping[:serialized_result])
  end
  response
end

.get_paginator(query, _parent) ⇒ Object 



93
94
95
96
97
98
99
100
101
102
103
 
# File 'lib/deep_unrest/read.rb', line 93

def self.get_paginator(query, _parent)
  opts = query.dig(:paginate) || {}
  params = ActionController::Parameters.new(opts)

  case params[:type]
  when :offset
    OffsetPaginator.new(params)
  else
    PagedPaginator.new(params)
  end
end

.get_query_type(item) ⇒ Object 



174
175
176
177
178
 
# File 'lib/deep_unrest/read.rb', line 174

def self.get_query_type(item)
  return :detail unless plural?(item[:key])

  :list
end

.plural?(str) ⇒ Boolean

Returns:

  • (Boolean) 


24
25
26
 
# File 'lib/deep_unrest/read.rb', line 24

def self.plural?(str)
  str.pluralize == str && str.singularize != str
end

.query_item(ctx, mapping, mappings, parent_context, included, meta, addr, _parent) ⇒ Object

Raises:



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
 
# File 'lib/deep_unrest/read.rb', line 65

def self.query_item(ctx, mapping, mappings, parent_context, included, meta, addr, _parent)
  query = resolve_conditions(mapping[:query].deep_dup, parent_context)

  raise DeepUnrest::InvalidQuery unless query[:id] || query[:find]

  if query.key?(:if)
    return unless query[:if][:attribute] == query[:if][:matches]
  end

  record = if query.key?(:id)
             mapping[:scope].find(query[:id]) if query.key?(:id)
           else
             mapping[:scope].find_by!(query[:find])
           end

  next_addr = [*addr, mapping[:key]]

  result = {
    **mapping,
    addr: next_addr,
    record: record
  }

  included << result

  recurse_included_queries(ctx, result, mappings, parent_context, included, meta, [*next_addr, :include])
end

.query_list(ctx, item, mappings, parent_context, included, meta, addr, parent) ⇒ Object 



110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
 
# File 'lib/deep_unrest/read.rb', line 110

def self.query_list(ctx, item, mappings, parent_context, included, meta, addr, parent)
  base_query = item[:query].deep_dup
  extension = base_query.dig(:extend, parent&.fetch(:record)&.id&.to_s&.underscore) || {}
  query = resolve_conditions(base_query.deep_merge(extension),
                             parent_context)

  paginator = get_paginator(query, parent)
  resource = item[:resource]

  # monkey patch the resource to only show authorized records
  old_records = resource.method(:records)
  resource.define_singleton_method(:records) { |ctx| item[:scope].merge(old_records.call(ctx)) }

  # transform sort value casing for rails
  sort_criteria = query[:sort]&.map { |s| s.clone.merge(field: s[:field].underscore) }
  serializer = JSONAPI::ResourceSerializer.new(resource)

  processor = JSONAPI::Processor.new(resource,
                                     :find,
                                     filters: query[:filter] || {},
                                     context: ctx,
                                     sort_criteria: sort_criteria,
                                     serializer: serializer,
                                     paginator: paginator)

  jsonapi_result = processor.process

  resource_results = format_processor_results(resource, jsonapi_result)

  # un-monkey patch the resource :records method
  resource.define_singleton_method(:records) { |ctx| old_records.call(ctx) }

  meta << {
    addr: [*addr, item[:key], 'meta'],
    serialized_result: {
      paginationParams: jsonapi_result.pagination_params,
      recordCount: jsonapi_result.record_count,
      sort: query[:sort],
      paginate: query[:paginate],
      filter: DeepUnrest.deep_camelize_keys(query[:filter])
    }
  }

  # make sure to return empty array if no results are found for this node
  if resource_results.empty?
    meta << {
      addr: [*addr, item[:key], 'data'],
      serialized_result: []
    }
  end

  resource_results.each_with_index do |record, i|
    next_addr = [*addr, item[:key], 'data[]', i]
    result = {
      **item,
      addr: next_addr,
      record: record._model
    }

    included << result
    recurse_included_queries(ctx, result, mappings, parent_context, included, meta, [*next_addr, :include])
  end
end

.read(ctx, params, user) ⇒ Object 



203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
 
# File 'lib/deep_unrest/read.rb', line 203

def self.read(ctx, params, user)
  # create mappings for assembly / disassembly
  mappings = create_read_mappings(params.to_unsafe_h, user)

  # authorize user for requested scope(s)
  DeepUnrest.authorization_strategy.authorize(mappings, user)

  # collect authorized scopes
  DeepUnrest.collect_authorized_scopes(mappings, user)

  # read data
  data, meta = execute_queries(ctx, mappings)

  # serialize using JSONAPI resource serializers
  serialize_results(ctx, data)

  # assemble results into something resembling shape of request
  format_response([*data, *meta])
end

.recurse_included_queries(ctx, item, mappings, parent_context, included, meta, addr) ⇒ Object 



54
55
56
57
58
59
60
61
62
63
 
# File 'lib/deep_unrest/read.rb', line 54

def self.recurse_included_queries(ctx, item, mappings, parent_context, included, meta, addr)
  return unless item[:query].key?(:include)

  item[:query][:include].each do |_k, v|
    next_context = parent_context.clone
    next_context[item[:key].singularize] = item[:record]
    next_mapping = mappings.find { |m| m[:uuid] == v[:uuid] }.clone
    execute_query(ctx, next_mapping, mappings, next_context, included, meta, addr, item)
  end
end

.resolve_conditions(query, parent_context) ⇒ Object 



34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
 
# File 'lib/deep_unrest/read.rb', line 34

def self.resolve_conditions(query, parent_context)
  if query.is_a? Array
    query.each { |item| resolve_conditions(item, parent_context) }
  elsif query.is_a? Hash
    query.each do |k, v|
      next unless v.is_a? Hash

      if v[:from_context]
        name, attr = v[:from_context].split('.')
        next unless parent_context[name]

        query[k] = parent_context[name].send(attr.underscore)
      else
        resolve_conditions(v, parent_context)
      end
    end
  end
  query
end

.serialize_results(ctx, data) ⇒ Object 



28
29
30
31
32
 
# File 'lib/deep_unrest/read.rb', line 28

def self.serialize_results(ctx, data)
  data.each do |item|
    item[:serialized_result] = DeepUnrest.serialize_result(ctx, item)
  end
end