[v1.3] Sort facets value by alphanumerical or count order

[brunoocasali]

⚠️ This issue is generated, it means the examples and the namings do not necessarily correspond to the language of this repository.
Also, if you are a maintainer, please add any clarification and instructions about this issue.

Sorry if this is already wholly/partially implemented. Feel free to let me know about the state of this issue in the repo.

Related to meilisearch/integration-guides#280

---

This issue is divided into two sections, first, you need to make the implementation, and second, you must update the code-samples (no one likes outdated docs, right?).

New implementation

Related to:

• issue: Sort facets value by alphanumerical or count order meilisearch#3612
• discussion: Retrieve facet values sorted by the number of corresponding documents product#519 (comment)
• spec: Faceting Setting API - sortFacetValuesBy  specifications#247

Adds the ability to sort facets by their value which could be by using alpha or count.

Ensure the SDKs can handle the new index faceting configuration attribute sortFacetValuesBy. This enum could only take count or alpha.

The faceting configuration now have two attributes:

maxValuesPerFacet: integer
sortFacetValuesBy: object 
  index_name: alpha|count
  *: alpha|count // when should be applied to all indexes

Code samples

Inside of this file: .code-samples.meilisearch.yml:

1. Create a new entry with this key facet_search_2 containing a call to the updateFaceting() settings method.
   "Translate" the following curl example: https://github.com/meilisearch/documentation/blob/e4fdc3d485c22e31a045b8a71bacf18b6a7d50e0/.code-samples.meilisearch.yaml#L1078

2. Update getting_started_faceting key to contain the new behavior sortFacetValuesBy
   Refer to this curl example: https://github.com/meilisearch/documentation/blob/e4fdc3d485c22e31a045b8a71bacf18b6a7d50e0/.code-samples.meilisearch.yaml#L875

3. Update update_faceting_settings_1 key to contain the new behavior sortFacetValuesBy
   Refer to this curl example: https://github.com/meilisearch/documentation/blob/e4fdc3d485c22e31a045b8a71bacf18b6a7d50e0/.code-samples.meilisearch.yaml#L854

update_faceting_settings_1: |-
  PATCH 'http://localhost:7700/indexes/books/settings/faceting' 
  with data: {
    "maxValuesPerFacet": 2,
    "sortFacetValuesBy": {
      "*": "alpha",
      "genres": "count"
    }
  }

TODO:

• Add the ability receive a new param in the updateFaceting settings method called sortFacetValuesBy.
• Update the code-samples accordingly
• Add integration tests

[danFbach]

@brunoocasali working on this one as well. does it need to process the facet name into camel case for the user, or is it on the user to provide the correct facet name?

I'm implementing the sortFacetValuesBy type as an enum which will utilizes JsonStringEnumConverter.

I have modified Faceting:

namespace Meilisearch
{
    /// <summary>
    /// Faceting configuration.
    /// </summary>
    public class Faceting
    {
        /// <summary>
        /// Gets or sets maxValuesPerFacet.
        /// </summary>
        [JsonPropertyName("maxValuesPerFacet")]
        public int MaxValuesPerFacet { get; set; }

        /// <summary>
        /// Gets or sets sortFacetValuesBy.
        /// </summary>
        [JsonPropertyName("sortFacetValuesBy")]
        public Dictionary<string, SortFacetValuesBy> SortFacetValuesBy { get; set; }
    }

    [JsonConverter(typeof(JsonStringEnumConverter))]
    public enum SortFacetValuesBy
    {
        /// <summary>
        /// Sort by alpha value.
        /// </summary>
        Alpha,

        /// <summary>
        /// Sort by count value.
        /// </summary>
        Count
    }
}

does the key of the dictionary, the facet name, need any automatic JSON serialization to comply with camelcase?