job_search.rb

class JobSearch
  class << self
    def create_index
      Tire.index self.to_s.downcase do
        delete

        create mappings: {
          job: {
            properties: {
              id: { type: 'string', index: 'not_analyzed', include_in_all: false},
              title: { type: 'string',analyzer: 'stemming', boost: 3.0}, # TODO Titel with synonyms
              description: {
                type: 'multi_field',
                fields: {
                  with_synonyms: {type:'string',analyzer: 'syn', boost: 0.5},
                  without_synonyms: {type:'string',analyzer: 'stemming', boost: 1.0},
                }
              },
              tags: { type: 'string', boost: 2.0},
              location: {type: 'geo_point'},
            }
          }
        },settings:{
          number_of_shards: 1,
          number_of_replicas: 0,
          similarity: {
            default: {
              type: "org.elasticsearch.index.similarity.CustomSimilarityProvider"
            }
          },
          analysis: {
            analyzer: {
              stemming: {
                type: 'snowball',
                language: 'German',
                filter: %w[standard lowercase]
              },
              syn: {
                tokenizer: "whitespace",
                filter: %w[standard lowercase synonym]
              }
            },
            filter: {
              german_stemmer: {
                type: 'stemmer',
                name: 'german2'
              },
              synonym: {
                type: "synonym",
                expand: 0, # =1 -> Ueberall wo Einkauf oder Logistik steht, steht dann "Einkauf Logistik"
                synonyms: [
                  "einkauf, logistik", # alle Werte werden wie der erste behandelt
                ]
              }
            }
          }
        }
        refresh
      end
    end

    def add jobs
      Tire.index self.to_s.downcase do
        jobs = jobs.map do |job|
          job.merge({type: 'job'})
        end
        import jobs
        refresh
      end
    end

    def search params
      Tire.search self.to_s.downcase do
        query do
          dis_max do
            query { string params, fields: ['title', 'description.with_synonyms', 'tags'], use_dis_max: false, default_operator: "AND" }
            query { string params, fields: ['title', 'description.without_synonyms', 'tags'], use_dis_max: false, default_operator: "AND"}
          end
        end
      end
    end
  end
end