Class: GdsApi::ListResponse
- Defined in:
- lib/gds_api/list_response.rb
Overview
Response class for lists of multiple items.
This expects responses to be in a common format, with the list of results contained under the ‘results` key. The response may also have previous and subsequent pages, indicated by entries in the response’s ‘Link` header.
Instance Method Summary collapse
- #has_next_page? ⇒ Boolean
- #has_previous_page? ⇒ Boolean
-
#initialize(response, api_client, options = {}) ⇒ ListResponse
constructor
The ListResponse is instantiated with a reference back to the API client, so it can make requests for the subsequent pages.
- #next_page ⇒ Object
- #previous_page ⇒ Object
- #results ⇒ Object
-
#with_subsequent_pages ⇒ Object
Transparently get all results across all pages.
Methods inherited from Response
#blank?, #cache_control, #code, #expires_at, #expires_in, #headers, #parsed_content, #present?, #raw_response_body, #to_hash
Constructor Details
#initialize(response, api_client, options = {}) ⇒ ListResponse
The ListResponse is instantiated with a reference back to the API client, so it can make requests for the subsequent pages
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# File 'lib/gds_api/list_response.rb', line 14 def initialize(response, api_client, = {}) super(response, ) @api_client = api_client end |
Instance Method Details
#has_next_page? ⇒ Boolean
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# File 'lib/gds_api/list_response.rb', line 30 def has_next_page? ! page_link("next").nil? end |
#has_previous_page? ⇒ Boolean
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# File 'lib/gds_api/list_response.rb', line 44 def has_previous_page? ! page_link("previous").nil? end |
#next_page ⇒ Object
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# File 'lib/gds_api/list_response.rb', line 34 def next_page # This shouldn't be a performance problem, since the cache will generally # avoid us making multiple requests for the same page, but we shouldn't # allow the data to change once it's already been loaded, so long as we # retain a reference to any one page in the sequence @next_page ||= if has_next_page? @api_client.get_list page_link("next").href end end |
#previous_page ⇒ Object
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# File 'lib/gds_api/list_response.rb', line 48 def previous_page # See the note in `next_page` for why this is memoised @previous_page ||= begin if has_previous_page? @api_client.get_list(page_link("previous").href) end end end |
#results ⇒ Object
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# File 'lib/gds_api/list_response.rb', line 23 def results # support group_by results from the content api by checking if there is a # grouped_results key present first. if it's not, then fallback to the # results key to_hash["grouped_results"] || to_hash["results"] end |
#with_subsequent_pages ⇒ Object
Transparently get all results across all pages. Compare this with #each or #results which only iterate over the current page.
Example:
list_response.with_subsequent_pages.each do |result|
...
end
or:
list_response.with_subsequent_pages.count
Pages of results are fetched on demand. When iterating, that means fetching pages as results from the current page are exhausted. If you invoke a method such as #count, this method will fetch all pages at that point. Note that the responses are stored so subsequent pages will not be loaded multiple times.
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# File 'lib/gds_api/list_response.rb', line 75 def with_subsequent_pages Enumerator.new { |yielder| self.each do |i| yielder << i end if has_next_page? next_page.with_subsequent_pages.each do |i| yielder << i end end } end |