Set the order of services

Specifications

To affect the display order of the services for a given merchant, set ranking_hint.score on each Service in the Service feed. 
// Ranking hints for a service.
message ServiceRankingHint {
  // Arbitrary partner or merchant assigned rank for this service.
  //
  // Services with a higher score will be shown more prominently (e.g. shown
  // higher in lists). Note that other factors may also influence ranking, such
  // as price, availability, user history, etc.
  //
  // Optional. Must be non-negative if set.
  optional float score = 1;
}
When multiple services are displayed (example: the page directly after the "Book" button that displays all the services for the user to chose from), it will use Service.ranking_hint.score as one of the signals to order the Services. The higher the score the higher on the page the Service will be displayed.

Example

A merchant has 3 services "Haircut", "Coloring", "Scalp massage and Haircut" and their preferred order is as follow:
  1. Haircut
  2. Scalp massage and Haircut
  3. Coloring
Service feed may be specified as follow:

Services

{
  "service": [
    {
      "price": {
        "currency_code": "USD",
        "price_micros": 20000000
      },
      "service_id": "haircut",
      "prepayment_type": "NOT_SUPPORTED",
      "merchant_id": "beauty-1",
      "localized_service_name": {
        "value": "Haircut",
        "localized_value": [
          {
            "locale": "en",
            "value": "Haircut"
          }
        ]
      },
      "localized_description": {
        "value": "Get a haircut.",
        "localized_value": [
          {
            "locale": "en",
            "value": "Get a haircut."
          }
        ]
      },
      "ranking_hint": {
        "score": 30.0
      }
    },
    {
      "localized_service_name": {
        "value": "Coloring",
        "localized_value": [
          {
            "locale": "en",
            "value": "Coloring"
          }
        ]
      },
      "price": {
        "currency_code": "USD",
        "price_micros": 40000000
      },
      "service_id": "haircoloring",
      "prepayment_type": "NOT_SUPPORTED",
      "merchant_id": "beauty-1",
      "localized_description": {
        "value": "Get your hair dyed.",
        "localized_value": [
          {
            "locale": "en",
            "value": "Get your hair dyed."
          }
        ]
      },
      "ranking_hint": {
        "score": 10.0
      }
    },
    {
      "localized_service_name": {
        "value": "Scalp massage and Haircut",
        "localized_value": [
          {
            "locale": "en",
            "value": "Scalp massage and Haircut"
          }
        ]
      },
      "price": {
        "currency_code": "USD",
        "price_micros": 30000000
      },
      "service_id": "scalpmassage",
      "prepayment_type": "NOT_SUPPORTED",
      "merchant_id": "beauty-1",
      "localized_description": {
        "value": "Get a shampoo and scalp massage followed by a haircut.",
        "localized_value": [
          {
            "locale": "en",
            "value": "Get a shampoo and scalp massage followed by a haircut."
          }
        ]
      },
      "ranking_hint": {
        "score": 20.0
      }
    }
  ]
}
The ordering specified above (without other signals) will result in:

Order of services: Haircut, Scalp massage and Haircut, Coloring.