Class: RecombeeApiClient::RecommendItemsToUser

Inherits:
ApiRequest
  • Object
show all
Defined in:
lib/recombee_api_client/api/recommend_items_to_user.rb

Overview

Based on the user’s past interactions (purchases, ratings, etc.) with the items, recommends top-N items that are most likely to be of high value for the given user.

The most typical use cases are recommendations on the homepage, in some “Picked just for you” section, or in email.

The returned items are sorted by relevance (the first item being the most relevant).

Besides the recommended items, also a unique recommId is returned in the response. It can be used to:

It is also possible to use POST HTTP method (for example in the case of a very long ReQL filter) - query parameters then become body parameters.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from HashNormalizer

#camelize, #normalize_hash_to_camel_case

Constructor Details

#initialize(user_id, count, optional = {}) ⇒ RecommendItemsToUser

  • *Required arguments*

    • user_id -> ID of the user for whom personalized recommendations are to be generated.

    • count -> Number of items to be recommended (N for the top-N recommendation).

  • *Optional arguments (given as hash optional)*

    • scenario -> Scenario defines a particular application of recommendations. It can be, for example, “homepage”, “cart”, or “emailing”.

You can set various settings to the [scenario](docs.recombee.com/scenarios) in the [Admin UI](admin.recombee.com). You can also see the performance of each scenario in the Admin UI separately, so you can check how well each application performs.

The AI that optimizes models to get the best results may optimize different scenarios separately or even use different models in each of the scenarios.

- +cascadeCreate+ -> If the user does not exist in the database, returns a list of non-personalized recommendations and creates the user in the database. This allows, for example, rotations in the following recommendations for that user, as the user will be already known to the system.

- +returnProperties+ -> With `returnProperties=true`, property values of the recommended items are returned along with their IDs in a JSON dictionary. The acquired property values can be used to easily display the recommended items to the user.

Example response: “‘json

{
  "recommId": "ce52ada4-e4d9-4885-943c-407db2dee837",
  "recomms":
    [
      {
        "id": "tv-178",
        "values": {
          "description": "4K TV with 3D feature",
          "categories":   ["Electronics", "Televisions"],
          "price": 342,
          "url": "myshop.com/tv-178"
        }
      },
      {
        "id": "mixer-42",
        "values": {
          "description": "Stainless Steel Mixer",
          "categories":   ["Home & Kitchen"],
          "price": 39,
          "url": "myshop.com/mixer-42"
        }
      }
    ],
   "numberNextRecommsCalls": 0
}

“‘

- +includedProperties+ -> Allows specifying which properties should be returned when `returnProperties=true` is set. The properties are given as a comma-separated list.

Example response for ‘includedProperties=description,price`: “`json

{
  "recommId": "a86ee8d5-cd8e-46d1-886c-8b3771d0520b",
  "recomms":
    [
      {
        "id": "tv-178",
        "values": {
          "description": "4K TV with 3D feature",
          "price": 342
        }
      },
      {
        "id": "mixer-42",
        "values": {
          "description": "Stainless Steel Mixer",
          "price": 39
        }
      }
    ],
  "numberNextRecommsCalls": 0
}

“‘

- +filter+ -> Boolean-returning [ReQL](https://docs.recombee.com/reql) expression, which allows you to filter recommended items based on the values of their attributes.

Filters can also be assigned to a [scenario](docs.recombee.com/scenarios) in the [Admin UI](admin.recombee.com).

- +booster+ -> Number-returning [ReQL](https://docs.recombee.com/reql) expression, which allows you to boost the recommendation rate of some items based on the values of their attributes.

Boosters can also be assigned to a [scenario](docs.recombee.com/scenarios) in the [Admin UI](admin.recombee.com).

- +logic+ -> Logic specifies the particular behavior of the recommendation models. You can pick tailored logic for your domain and use case.

See [this section](docs.recombee.com/recommendation_logics) for a list of available logics and other details.

The difference between logic and scenario is that logic specifies mainly behavior, while scenario specifies the place where recommendations are shown to the users.

Logic can also be set to a [scenario](docs.recombee.com/scenarios) in the [Admin UI](admin.recombee.com).

- +reqlExpressions+ -> A dictionary of [ReQL](https://docs.recombee.com/reql) expressions that will be executed for each recommended item.

This can be used to compute additional properties of the recommended items that are not stored in the database.

The keys are the names of the expressions, and the values are the actual ReQL expressions.

Example request: “‘json {

"reqlExpressions": {
  "isInUsersCity": "context_user[\"city\"] in 'cities'",
  "distanceToUser": "earth_distance('location', context_user[\"location\"])"
}

} “‘

Example response: “‘json {

"recommId": "ce52ada4-e4d9-4885-943c-407db2dee837",
"recomms":
  [
    {
      "id": "restaurant-178",
      "reqlEvaluations": {
        "isInUsersCity": true,
        "distanceToUser": 5200.2
      }
    },
    {
      "id": "bar-42",
      "reqlEvaluations": {
        "isInUsersCity": false,
        "distanceToUser": 2516.0
      }
    }
  ],
 "numberNextRecommsCalls": 0

} “‘

- +diversity+ -> **Expert option:** Real number from [0.0, 1.0], which determines how mutually dissimilar the recommended items should be. The default value is 0.0, i.e., no diversification. Value 1.0 means maximal diversification.

- +minRelevance+ -> **Expert option:** Specifies the threshold of how relevant must the recommended items be to the user. Possible values one of: "low", "medium", "high". The default value is "low", meaning that the system attempts to recommend a number of items equal to *count* at any cost. If there is not enough data (such as interactions or item properties), this may even lead to bestseller-based recommendations to be appended to reach the full *count*. This behavior may be suppressed by using "medium" or "high" values. In such a case, the system only recommends items of at least the requested relevance and may return less than *count* items when there is not enough data to fulfill it.

- +rotationRate+ -> **Expert option:** If your users browse the system in real-time, it may easily happen that you wish to offer them recommendations multiple times. Here comes the question: how much should the recommendations change? Should they remain the same, or should they rotate? Recombee API allows you to control this per request in a backward fashion. You may penalize an item for being recommended in the near past. For the specific user, `rotationRate=1` means maximal rotation, `rotationRate=0` means absolutely no rotation. You may also use, for example, `rotationRate=0.2` for only slight rotation of recommended items. Default: `0`.

- +rotationTime+ -> **Expert option:** Taking *rotationRate* into account, specifies how long it takes for an item to recover from the penalization. For example, `rotationTime=7200.0` means that items recommended less than 2 hours ago are penalized. Default: `7200.0`.

- +expertSettings+ -> Dictionary of custom options.

- +returnAbGroup+ -> If there is a custom AB-testing running, return the name of the group to which the request belongs.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 169

def initialize(user_id, count, optional = {})
  @user_id = user_id
  @count = count
  optional = normalize_hash_to_camel_case(optional)
  @scenario = optional['scenario']
  @cascade_create = optional['cascadeCreate']
  @return_properties = optional['returnProperties']
  @included_properties = optional['includedProperties']
  @filter = optional['filter']
  @booster = optional['booster']
  @logic = optional['logic']
  @reql_expressions = optional['reqlExpressions']
  @diversity = optional['diversity']
  @min_relevance = optional['minRelevance']
  @rotation_rate = optional['rotationRate']
  @rotation_time = optional['rotationTime']
  @expert_settings = optional['expertSettings']
  @return_ab_group = optional['returnAbGroup']
  @optional = optional
  @timeout = 3000
  @ensure_https = false
  @optional.each do |par, _|
    raise UnknownOptionalParameter.new(par) unless %w[scenario cascadeCreate returnProperties
                                                      includedProperties filter booster logic reqlExpressions diversity minRelevance rotationRate rotationTime expertSettings returnAbGroup].include? par
  end
end

Instance Attribute Details

#booster ⇒ Object (readonly)

Returns the value of attribute booster.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def booster
  @booster
end

#cascade_create ⇒ Object (readonly)

Returns the value of attribute cascade_create.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def cascade_create
  @cascade_create
end

#count ⇒ Object (readonly)

Returns the value of attribute count.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def count
  @count
end

#diversity ⇒ Object (readonly)

Returns the value of attribute diversity.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def diversity
  @diversity
end

#ensure_https ⇒ Object

Returns the value of attribute ensure_https.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 26

def ensure_https
  @ensure_https
end

#expert_settings ⇒ Object (readonly)

Returns the value of attribute expert_settings.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def expert_settings
  @expert_settings
end

#filter ⇒ Object (readonly)

Returns the value of attribute filter.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def filter
  @filter
end

#included_properties ⇒ Object (readonly)

Returns the value of attribute included_properties.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def included_properties
  @included_properties
end

#logic ⇒ Object (readonly)

Returns the value of attribute logic.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def logic
  @logic
end

#min_relevance ⇒ Object (readonly)

Returns the value of attribute min_relevance.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def min_relevance
  @min_relevance
end

#reql_expressions ⇒ Object (readonly)

Returns the value of attribute reql_expressions.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def reql_expressions
  @reql_expressions
end

#return_ab_group ⇒ Object (readonly)

Returns the value of attribute return_ab_group.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def return_ab_group
  @return_ab_group
end

#return_properties ⇒ Object (readonly)

Returns the value of attribute return_properties.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def return_properties
  @return_properties
end

#rotation_rate ⇒ Object (readonly)

Returns the value of attribute rotation_rate.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def rotation_rate
  @rotation_rate
end

#rotation_time ⇒ Object (readonly)

Returns the value of attribute rotation_time.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def rotation_time
  @rotation_time
end

#scenario ⇒ Object (readonly)

Returns the value of attribute scenario.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def scenario
  @scenario
end

#timeout ⇒ Object

Returns the value of attribute timeout.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 26

def timeout
  @timeout
end

#user_id ⇒ Object (readonly)

Returns the value of attribute user_id.



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 24

def user_id
  @user_id
end

Instance Method Details

#body_parameters ⇒ Object

Values of body parameters as a Hash



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 202

def body_parameters
  p = {}
  p['count'] = @count
  p['scenario'] = @optional['scenario'] if @optional.include? 'scenario'
  p['cascadeCreate'] = @optional['cascadeCreate'] if @optional.include? 'cascadeCreate'
  p['returnProperties'] = @optional['returnProperties'] if @optional.include? 'returnProperties'
  p['includedProperties'] = @optional['includedProperties'] if @optional.include? 'includedProperties'
  p['filter'] = @optional['filter'] if @optional.include? 'filter'
  p['booster'] = @optional['booster'] if @optional.include? 'booster'
  p['logic'] = @optional['logic'] if @optional.include? 'logic'
  p['reqlExpressions'] = @optional['reqlExpressions'] if @optional.include? 'reqlExpressions'
  p['diversity'] = @optional['diversity'] if @optional.include? 'diversity'
  p['minRelevance'] = @optional['minRelevance'] if @optional.include? 'minRelevance'
  p['rotationRate'] = @optional['rotationRate'] if @optional.include? 'rotationRate'
  p['rotationTime'] = @optional['rotationTime'] if @optional.include? 'rotationTime'
  p['expertSettings'] = @optional['expertSettings'] if @optional.include? 'expertSettings'
  p['returnAbGroup'] = @optional['returnAbGroup'] if @optional.include? 'returnAbGroup'

  p
end

#method ⇒ Object

HTTP method



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 197

def method
  :post
end

#path ⇒ Object

Relative path to the endpoint



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 230

def path
  "/{databaseId}/recomms/users/#{@user_id}/items/"
end

#query_parameters ⇒ Object

Values of query parameters as a Hash. name of parameter => value of the parameter



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# File 'lib/recombee_api_client/api/recommend_items_to_user.rb', line 225

def query_parameters
  {}
end