/*
* Method: ClassifyText
*
* Description: This method can be used to classify the document into categories. Each category is
* identified by a name and associated with a confidence number indicating how confident the API is
* about the classification.
*
* Parameters:
* - document (Document): The document/text on which you want Natural Language API to perform analysis.
*
* - APIKey (String): Implicity required paramter which should be set through the constructor when
* creating an object of this class. For more details about the Google API Key please see:
* https://developers.google.com/places/web-service/get-api-key
*
* Return: The method returns a tuple of two items. If the query is successful, then the first item will
* be an object of type ClassifyTextResponse. If the query is unsuccessful and an error is returned,
* then the method returns null. The second element is a ResponseStatus object indicating the status of
* the query along with the appropiate HTTP code. Since the HTTP query is performed asynchronously, the
* return object is wrapped in Task<>.
*/
public async Task <Tuple <ClassifyTextResponse, ResponseStatus> > ClassifyText(Document document)
{
if (BasicFunctions.isEmpty(APIKey))
{
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null, NaturalLanguageStatus.MISSING_API_KEY));
}
if (document == null)
{
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null, NaturalLanguageStatus.MISSING_DOCUMENT));
}
ClassifyTextRequest classifyTextRequest = new ClassifyTextRequest(document);
if (classifyTextRequest == null)
{
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null, NaturalLanguageStatus.INTERNAL_SERVER_ERROR));
}
// Preparing the header to send a JSON request body
httpClient.DefaultRequestHeaders.Accept.Clear();
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
// API address to which we make the HTTP POST query
String request_query = "v1/documents:classifyText?" + $"key={APIKey}";
HttpResponseMessage response = await httpClient.PostAsJsonAsync(request_query, classifyTextRequest);
Stream stream = await response.Content.ReadAsStreamAsync();
StreamReader streamReader = new StreamReader(stream);
String response_str = streamReader.ReadToEnd();
// Similar two-step hop as we have seen in prior methods
if (response.IsSuccessStatusCode)
{
ClassifyTextResponse classifyTextResponse;
try {
classifyTextResponse = JsonConvert.DeserializeObject <ClassifyTextResponse>(response_str);
if (classifyTextResponse == null || classifyTextResponse.Categories.Count == 0)
{
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null, NaturalLanguageStatus.ZERO_RESULTS));
}
} catch (JsonSerializationException e) {
Debug.WriteLine(e.StackTrace);
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null, NaturalLanguageStatus.DESERIALIZATION_ERROR));
}
return(new Tuple <ClassifyTextResponse, ResponseStatus>(classifyTextResponse, NaturalLanguageStatus.OK));
}
else
{
// If the query is not successful, then we try to extract details about the error from the response
ClassifyTextResponse classifyTextResponse;
try {
classifyTextResponse = JsonConvert.DeserializeObject <ClassifyTextResponse>(response_str);
} catch (JsonSerializationException e) {
Debug.WriteLine(e.StackTrace);
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null, NaturalLanguageStatus.DESERIALIZATION_ERROR));
}
/*
* If no error details are available, then we use the information from the response to determine
* the appropriate error code.
* If we do have an Error object, then we use it to identify the appropriate error code and message
*/
if (classifyTextResponse.Error == null)
{
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null,
NaturalLanguageStatus.processErrorMessage(response.StatusCode.ToString(), response.ReasonPhrase)));
}
else
{
return(new Tuple <ClassifyTextResponse, ResponseStatus>(null,
NaturalLanguageStatus.processErrorMessage(classifyTextResponse.Error.Code.ToString(), classifyTextResponse.Error.Message)));
}
}
}
/*
* Method: AnalyzeEntities
*
* Description: This method can be used to find entities in a document or text. If you only wish to run
* sentiment analysis on each entity, simultaneously, then please use the AnalyzeEntitySentiment()
* method.
*
* Parameters:
* - document (Document): The document/text from which you want Natural Language API to identify and
* analyze entities.
* - encodingType (EncodingType): The encoding type to help the API determine offsets. Acceptable values
* are NONE, UTF8, UTF16, UTF32. If NONE is specified, then encoding-specific information is not set.
*
* - APIKey (String): Implicity required paramter which should be set through the constructor when
* creating an object of this class. For more details about the Google API Key please see:
* https://developers.google.com/places/web-service/get-api-key
*
* Return: The method returns a tuple of two items. If the query is successful, then the first item will
* be an object of type AnalyzeEntitiesResponse, which conatins a list of all the entities identified and
* the language of the document. If the query is unsuccessful and an error is returned, then the method
* returns null. The second element is a ResponseStatus object indicating the status of the query along
* with the appropiate HTTP code. Since the HTTP query is performed asynchronously, the return object is
* wrapped in Task<>.
*/
public async Task <Tuple <AnalyzeEntitiesResponse, ResponseStatus> > AnalyzeEntities(Document document, EncodingType encodingType)
{
if (BasicFunctions.isEmpty(APIKey))
{
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null, NaturalLanguageStatus.MISSING_API_KEY));
}
if (document == null)
{
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null, NaturalLanguageStatus.MISSING_DOCUMENT));
}
AnalyzeEntitiesRequest entitiesRequest = new AnalyzeEntitiesRequest(document, encodingType);
if (entitiesRequest == null)
{
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null, NaturalLanguageStatus.INTERNAL_SERVER_ERROR));
}
// Preparing the header to send a JSON request body
httpClient.DefaultRequestHeaders.Accept.Clear();
httpClient.DefaultRequestHeaders.Accept.Add(new MediaTypeWithQualityHeaderValue("application/json"));
// API address to which we make the HTTP POST query
String request_query = "v1/documents:analyzeEntities?" + $"key={APIKey}";
HttpResponseMessage response = await httpClient.PostAsJsonAsync(request_query, entitiesRequest);
Stream stream = await response.Content.ReadAsStreamAsync();
StreamReader streamReader = new StreamReader(stream);
String response_str = streamReader.ReadToEnd();
/*
* Similar two-step hop as we have seen before. We try to deserialize the response string, expecting
* an object of AnalyzeEntitiesResponse. If the response is not an AnalyzeEntitiesResponse object,
* then we will encounter a JSONSerialization error and return null. If it is as we expect, then we
* just return the AnalyzeEntitiesResponse object, so long as it is not empty or null.
*/
if (response.IsSuccessStatusCode)
{
AnalyzeEntitiesResponse entitiesResponse;
try {
entitiesResponse = JsonConvert.DeserializeObject <AnalyzeEntitiesResponse>(response_str);
if (entitiesResponse == null || entitiesResponse.Entities.Count == 0)
{
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null, NaturalLanguageStatus.ZERO_RESULTS));
}
} catch (JsonSerializationException e) {
Debug.WriteLine(e.StackTrace);
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null, NaturalLanguageStatus.DESERIALIZATION_ERROR));
}
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(entitiesResponse, NaturalLanguageStatus.OK));
}
else
{
// If the query is not successful, then we try to extract details about the error from the response
AnalyzeEntitiesResponse entitiesResponse;
try {
entitiesResponse = JsonConvert.DeserializeObject <AnalyzeEntitiesResponse>(response_str);
} catch (JsonSerializationException e) {
Debug.WriteLine(e.StackTrace);
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null, NaturalLanguageStatus.DESERIALIZATION_ERROR));
}
// If no error details are available, then we use the information from the response to determine
// the appropriate error code
if (entitiesResponse.Error == null)
{
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null,
NaturalLanguageStatus.processErrorMessage(response.StatusCode.ToString(), response.ReasonPhrase)));
}
else
{
// If we do have an Error object, then we use it to identify the appropriate error code and message
return(new Tuple <AnalyzeEntitiesResponse, ResponseStatus>(null,
NaturalLanguageStatus.processErrorMessage(entitiesResponse.Error.Code.ToString(), entitiesResponse.Error.Message)));
}
}
}
