/// <summary>
/// Gets a list of query suggestions for providing typeahead support.
/// </summary>
public override async Task <GetQuerySuggestionsResponse> GetQuerySuggestions(GetQuerySuggestionsRequest request, ServerCallContext context)
{
string firstLetter = request.Query.Substring(0, 1);
PreparedStatement preparedStatement = await _statementCache.GetOrAddAsync("SELECT tag FROM tags_by_letter WHERE first_letter = ? AND tag >= ? LIMIT ?");
BoundStatement boundStatement = preparedStatement.Bind(firstLetter, request.Query, request.PageSize);
RowSet rows = await _session.ExecuteAsync(boundStatement).ConfigureAwait(false);
var response = new GetQuerySuggestionsResponse
{
Query = request.Query
};
response.Suggestions.Add(rows.Select(row => row.GetValue <string>("tag")));
return(response);
}
/// <summary>
/// Gets a list of query suggestions for providing typeahead support.
/// </summary>
public override async Task <GetQuerySuggestionsResponse> GetQuerySuggestions(GetQuerySuggestionsRequest request, ServerCallContext context)
{
// Get REST client for dse-search service
Uri searchUri = await GetDseSearchUri().ConfigureAwait(false);
IRestClient restClient = _createRestClient(searchUri);
var restRequest = new RestRequest("killrvideo.videos/suggest")
{
Method = Method.POST
};
restRequest.AddParameter("wt", "json");
// We'll build on every query, but in a real production app, we'd probably only do this occasionally or use the Solr config to setup
// build on commit/optimize of the index
restRequest.AddParameter("suggest.build", "true");
restRequest.AddParameter("suggest.q", request.Query);
IRestResponse <SearchResult> restResponse = await restClient.ExecuteTaskAsync <SearchResult>(restRequest).ConfigureAwait(false);
// Start with an empty response (i.e. no suggestions)
var response = new GetQuerySuggestionsResponse {
Query = request.Query
};
// Check for network/timeout errors
if (restResponse.ResponseStatus != ResponseStatus.Completed)
{
// TODO: Logger.Error(response.ErrorException, "Error while querying Solr search suggestions from {host} for {query}", nodeIp, getSuggestions.Query);
return(response);
}
// Check for HTTP error codes
if (restResponse.StatusCode != HttpStatusCode.OK)
{
// TODO: Logger.Error("HTTP status code {code} while querying Solr video suggestions from {host} for {query}", (int)response.StatusCode, nodeIp, getSuggestions.Query);
return(response);
}
// Success, add responses from DSE Search to gRPC response
response.Suggestions.Add(
restResponse.Data.Suggest.SearchSuggester[request.Query].Suggestions.Select(s => s.Term)
);
return(response);
}
/// <summary>
/// Gets a list of query suggestions for providing typeahead support.
/// </summary>
public override async Task <GetQuerySuggestionsResponse> GetQuerySuggestions(GetQuerySuggestionsRequest request, ServerCallContext context)
{
// Set the base URL of the REST client to use the first node in the Cassandra cluster
string nodeIp = _session.Cluster.AllHosts().First().Address.Address.ToString();
_restClient.BaseUrl = new Uri($"http://{nodeIp}:8983/solr");
var restRequest = new RestRequest("killrvideo.videos/suggest")
{
Method = Method.POST
};
restRequest.AddParameter("wt", "json");
// Requires a build after new names are added, added on a safe side.
restRequest.AddParameter("spellcheck.build", "true");
restRequest.AddParameter("spellcheck.q", request.Query);
IRestResponse <SearchSuggestionResult> restResponse = await _restClient.ExecuteTaskAsync <SearchSuggestionResult>(restRequest).ConfigureAwait(false);
// Start with an empty response (i.e. no suggestions)
var response = new GetQuerySuggestionsResponse {
Query = request.Query
};
// Check for network/timeout errors
if (restResponse.ResponseStatus != ResponseStatus.Completed)
{
// TODO: Logger.Error(response.ErrorException, "Error while querying Solr search suggestions from {host} for {query}", nodeIp, getSuggestions.Query);
return(response);
}
// Check for HTTP error codes
if (restResponse.StatusCode != HttpStatusCode.OK)
{
// TODO: Logger.Error("HTTP status code {code} while querying Solr video suggestions from {host} for {query}", (int)response.StatusCode, nodeIp, getSuggestions.Query);
return(response);
}
// Success
/*
* The spellcheck.suggestions object that comes back in the JSON looks something like this (for example, searching for 'cat'):
*
* "suggestions": [
* "cat",
* {
* "numFound": 1,
* "startOffset": 0,
* "endOffset": 3,
* "suggestion": [
* "cat summer video teaser"
* ]
* }
* ]
*
* Yes, that's an array of mixed objects (seriously, WTF kind of an API is that Solr?!). Since the array is mixed, we deserialized
* it as a List<string> where the second element will be the JSON string with the actual data we care about. We need to now run
* deserialization again on that to get at the actual data.
*/
if (restResponse.Data.Spellcheck.Suggestions.Count >= 2)
{
// Deserialize the embedded object
var suggestions = JsonConvert.DeserializeObject <SearchSpellcheckSuggestions>(restResponse.Data.Spellcheck.Suggestions.Last());
// Add to response if the object deserialized correctly
if (suggestions.Suggestion != null)
{
response.Suggestions.Add(suggestions.Suggestion);
}
}
return(response);
}