Schritt 4 – .NET-Suchcode erkunden

In den vorherigen Lektionen haben Sie einer statischen Web-App eine Suchfunktion hinzugefügt. In dieser Lektion werden die wesentlichen Schritte zum Einrichten der Integration hervorgehoben. Dieser Artikel kann als Spickzettel für die Integration von Suchfunktionen in Ihre Web-App herangezogen werden.

Azure SDK Azure.Search.Documents

Die Funktions-App verwendet das Azure SDK für Azure KI Search:

• NuGet: Azure.Search.Documents
• Referenzdokumentation: Clientbibliothek

Die Funktions-App authentifiziert sich über das SDK bei der cloudbasierten Azure KI Search-API unter Verwendung Ihres Ressourcennamens, Ressourcenschlüssels und Indexnamens. Die Geheimnisse sind in den Einstellungen der statischen Web-App gespeichert und werden als Umgebungsvariablen in die Funktion gepullt.

Konfigurieren von Geheimnissen in der Datei „local.settings.json“

{
  "IsEncrypted": false,
  "Values": {
    "AzureWebJobsStorage": "",
    "FUNCTIONS_WORKER_RUNTIME": "dotnet-isolated",
    "SearchApiKey": "",
    "SearchServiceName": "",
    "SearchIndexName": "good-books"
  },
  "Host": {
    "CORS": "*"
  }
}

Azure-Funktion: Durchsuchen des Katalogs

Die Search-API akzeptiert einen Suchbegriff, durchsucht die Dokumente im Suchindex und gibt eine Liste mit Treffern zurück.

Azure Functions ruft die Informationen der Suchkonfiguration per Pull ab und führt die Abfrage aus.

using Azure;
using Azure.Core.Serialization;
using Azure.Search.Documents;
using Azure.Search.Documents.Models;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;
using System.Net;
using System.Text.Json;
using System.Text.Json.Serialization;
using WebSearch.Models;
using SearchFilter = WebSearch.Models.SearchFilter;

namespace WebSearch.Function
{
    public class Search
    {
        private static string searchApiKey = Environment.GetEnvironmentVariable("SearchApiKey", EnvironmentVariableTarget.Process);
        private static string searchServiceName = Environment.GetEnvironmentVariable("SearchServiceName", EnvironmentVariableTarget.Process);
        private static string searchIndexName = Environment.GetEnvironmentVariable("SearchIndexName", EnvironmentVariableTarget.Process) ?? "good-books";

        private readonly ILogger<Lookup> _logger;

        public Search(ILogger<Lookup> logger)
        {
            _logger = logger;
        }

        [Function("search")]
        public async Task<HttpResponseData> RunAsync(
            [HttpTrigger(AuthorizationLevel.Anonymous, "post")] HttpRequestData req, 
            FunctionContext executionContext)
        {
            string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
            var data = JsonSerializer.Deserialize<RequestBodySearch>(requestBody);

            // Azure AI Search 
            Uri serviceEndpoint = new($"https://{searchServiceName}.search.windows.net/");

            SearchClient searchClient = new(
                serviceEndpoint,
                searchIndexName,
                new AzureKeyCredential(searchApiKey)
            );

            SearchOptions options = new()

            {
                Size = data.Size,
                Skip = data.Skip,
                IncludeTotalCount = true,
                Filter = CreateFilterExpression(data.Filters)
            };
            options.Facets.Add("authors");
            options.Facets.Add("language_code");

            SearchResults<SearchDocument> searchResults = searchClient.Search<SearchDocument>(data.SearchText, options);

            var facetOutput = new Dictionary<string, IList<FacetValue>>();
            foreach (var facetResult in searchResults.Facets)
            {
                facetOutput[facetResult.Key] = facetResult.Value
                           .Select(x => new FacetValue { value = x.Value.ToString(), count = x.Count })

                           .ToList();
            }

            // Data to return 
            var output = new SearchOutput
            {
                Count = searchResults.TotalCount,
                Results = searchResults.GetResults().ToList(),
                Facets = facetOutput
            };
            
            var response = req.CreateResponse(HttpStatusCode.Found);

            // Serialize data
            var serializer = new JsonObjectSerializer(
                new JsonSerializerOptions(JsonSerializerDefaults.Web));
            await response.WriteAsJsonAsync(output, serializer);

            return response;
        }

        public static string CreateFilterExpression(List<SearchFilter> filters)
        {
            if (filters is null or { Count: <= 0 })
            {
                return null;
            }

            List<string> filterExpressions = new();


            List<SearchFilter> authorFilters = filters.Where(f => f.field == "authors").ToList();
            List<SearchFilter> languageFilters = filters.Where(f => f.field == "language_code").ToList();

            List<string> authorFilterValues = authorFilters.Select(f => f.value).ToList();

            if (authorFilterValues.Count > 0)
            {
                string filterStr = string.Join(",", authorFilterValues);
                filterExpressions.Add($"{"authors"}/any(t: search.in(t, '{filterStr}', ','))");
            }

            List<string> languageFilterValues = languageFilters.Select(f => f.value).ToList();
            foreach (var value in languageFilterValues)
            {
                filterExpressions.Add($"language_code eq '{value}'");
            }

            return string.Join(" and ", filterExpressions);
        }
    }
}

Client: Suchen über den Katalog

Rufen Sie mithilfe des folgenden Codes die Azure-Funktion im React-Client auf:

import React, { useEffect, useState } from 'react';
import axios from 'axios';
import CircularProgress  from '@mui/material/CircularProgress';
import { useLocation, useNavigate } from "react-router-dom";

import Results from '../../components/Results/Results';
import Pager from '../../components/Pager/Pager';
import Facets from '../../components/Facets/Facets';
import SearchBar from '../../components/SearchBar/SearchBar';

import "./Search.css";

export default function Search() {
  
  let location = useLocation();
  const navigate = useNavigate();
  
  const [ results, setResults ] = useState([]);
  const [ resultCount, setResultCount ] = useState(0);
  const [ currentPage, setCurrentPage ] = useState(1);
  const [ q, setQ ] = useState(new URLSearchParams(location.search).get('q') ?? "*");
  const [ top ] = useState(new URLSearchParams(location.search).get('top') ?? 8);
  const [ skip, setSkip ] = useState(new URLSearchParams(location.search).get('skip') ?? 0);
  const [ filters, setFilters ] = useState([]);
  const [ facets, setFacets ] = useState({});
  const [ isLoading, setIsLoading ] = useState(true);

  let resultsPerPage = top;
  
  useEffect(() => {
    setIsLoading(true);
    setSkip((currentPage-1) * top);
    const body = {
      q: q,
      top: top,
      skip: skip,
      filters: filters
    };

    axios.post( '/api/search', body)
      .then(response => {
            console.log(JSON.stringify(response.data))
            setResults(response.data.results);
            setFacets(response.data.facets);
            setResultCount(response.data.count);
            setIsLoading(false);
        } )
        .catch(error => {
            console.log(error);
            setIsLoading(false);
        });
    
  }, [q, top, skip, filters, currentPage]);

  // pushing the new search term to history when q is updated
  // allows the back button to work as expected when coming back from the details page
  useEffect(() => {
    navigate('/search?q=' + q);  
    setCurrentPage(1);
    setFilters([]);
    // eslint-disable-next-line react-hooks/exhaustive-deps
  }, [q]);


  let postSearchHandler = (searchTerm) => {
    //console.log(searchTerm);
    setQ(searchTerm);
  }

  var body;
  if (isLoading) {
    body = (
      <div className="col-md-9">
        <CircularProgress />
      </div>);
  } else {
    body = (
      <div className="col-md-9">
        <Results documents={results} top={top} skip={skip} count={resultCount}></Results>
        <Pager className="pager-style" currentPage={currentPage} resultCount={resultCount} resultsPerPage={resultsPerPage} setCurrentPage={setCurrentPage}></Pager>
      </div>
    )
  }

  return (
    <main className="main main--search container-fluid">
      
      <div className="row">
        <div className="col-md-3">
          <div className="search-bar">
            <SearchBar postSearchHandler={postSearchHandler} q={q}></SearchBar>
          </div>
          <Facets facets={facets} filters={filters} setFilters={setFilters}></Facets>
        </div>
        {body}
      </div>
    </main>
  );
}

Azure-Funktion: Vorschläge aus dem Katalog

Die Vorschlags-API nimmt einen Suchbegriff während der Eingabe eines Benutzers entgegen und schlägt Suchbegriffe wie Buchtitel und Autoren aus den Dokumenten im Suchindex vor. Dabei wird eine kurze Liste mit Treffern zurückgegeben.

Der Suchvorschlagsfunktion (sg) wird in der bei Massenuploadvorgängen verwendeten Schemadatei definiert.

using Azure;
using Azure.Core.Serialization;
using Azure.Search.Documents;
using Azure.Search.Documents.Models;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;
using System.Net;
using System.Text.Json;
using WebSearch.Models;

namespace WebSearch.Function
{
    public class Suggest
    {
        private static string searchApiKey = Environment.GetEnvironmentVariable("SearchApiKey", EnvironmentVariableTarget.Process);
        private static string searchServiceName = Environment.GetEnvironmentVariable("SearchServiceName", EnvironmentVariableTarget.Process);
        private static string searchIndexName = Environment.GetEnvironmentVariable("SearchIndexName", EnvironmentVariableTarget.Process) ?? "good-books";

        private readonly ILogger<Lookup> _logger;

        public Suggest(ILogger<Lookup> logger)
        {
            _logger = logger;
        }

        [Function("suggest")]
        public async Task<HttpResponseData> RunAsync(
            [HttpTrigger(AuthorizationLevel.Anonymous, "post")] HttpRequestData req, 
            FunctionContext executionContext)
        {
            // Get Document Id
            string requestBody = await new StreamReader(req.Body).ReadToEndAsync();
            var data = JsonSerializer.Deserialize<RequestBodySuggest>(requestBody);

            // Azure AI Search 
            Uri serviceEndpoint = new($"https://{searchServiceName}.search.windows.net/");

            SearchClient searchClient = new(

                serviceEndpoint,
                searchIndexName,
                new AzureKeyCredential(searchApiKey)
            );

            SuggestOptions options = new()

            {
                Size = data.Size
            };

            var suggesterResponse = await searchClient.SuggestAsync<BookModel>(data.SearchText, data.SuggesterName, options);
            
            // Data to return
            var searchSuggestions = new Dictionary<string, List<SearchSuggestion<BookModel>>>
            {
                ["suggestions"] = suggesterResponse.Value.Results.ToList()
            };

            var response = req.CreateResponse(HttpStatusCode.Found);

            // Serialize data
            var serializer = new JsonObjectSerializer(
                new JsonSerializerOptions(JsonSerializerDefaults.Web));
            await response.WriteAsJsonAsync(searchSuggestions, serializer);
            
            return response;
        }
    }
}

Client: Vorschläge aus dem Katalog

Die Vorschlags-API wird in der React-App unter \client\src\components\SearchBar\SearchBar.js im Rahmen der Komponenteninitialisierung aufgerufen:

import React, {useState, useEffect} from 'react';
import axios from 'axios';
import Suggestions from './Suggestions/Suggestions';

import "./SearchBar.css";

export default function SearchBar(props) {

    let [q, setQ] = useState("");
    let [suggestions, setSuggestions] = useState([]);
    let [showSuggestions, setShowSuggestions] = useState(false);

    const onSearchHandler = () => {
        props.postSearchHandler(q);
        setShowSuggestions(false);
    }

    const suggestionClickHandler = (s) => {
        document.getElementById("search-box").value = s;
        setShowSuggestions(false);
        props.postSearchHandler(s);    
    }

    const onEnterButton = (event) => {
        if (event.keyCode === 13) {
            onSearchHandler();
        }
    }

    const onChangeHandler = () => {
        var searchTerm = document.getElementById("search-box").value;
        setShowSuggestions(true);
        setQ(searchTerm);

        // use this prop if you want to make the search more reactive
        if (props.searchChangeHandler) {
            props.searchChangeHandler(searchTerm);
        }
    }

    useEffect(_ =>{
        const timer = setTimeout(() => {
            const body = {
                q: q,
                top: 5,
                suggester: 'sg'
            };

            if (q === '') {
                setSuggestions([]);
            } else {
                axios.post( '/api/suggest', body)
                .then(response => {
                    console.log(JSON.stringify(response.data))
                    setSuggestions(response.data.suggestions);
                } )
                .catch(error => {
                    console.log(error);
                    setSuggestions([]);
                });
            }
        }, 300);
        return () => clearTimeout(timer);
    }, [q, props]);

    var suggestionDiv;
    if (showSuggestions) {
        suggestionDiv = (<Suggestions suggestions={suggestions} suggestionClickHandler={(s) => suggestionClickHandler(s)}></Suggestions>);
    } else {
        suggestionDiv = (<div></div>);
    }

    return (
        <div >
            <div className="input-group" onKeyDown={e => onEnterButton(e)}>
                <div className="suggestions" >
                    <input 
                        autoComplete="off" // setting for browsers; not the app
                        type="text" 
                        id="search-box" 
                        className="form-control rounded-0" 
                        placeholder="What are you looking for?" 
                        onChange={onChangeHandler} 
                        defaultValue={props.q}
                        onBlur={() => setShowSuggestions(false)}
                        onClick={() => setShowSuggestions(true)}>
                    </input>
                    {suggestionDiv}
                </div>
                <div className="input-group-btn">
                    <button className="btn btn-primary rounded-0" type="submit" onClick={onSearchHandler}>
                        Search
                    </button>
                </div>
            </div>
        </div>
    );
};

Azure-Funktion: Abrufen eines bestimmten Dokuments

Die Dokumentlookup-API akzeptiert eine ID und gibt das Dokumentobjekt aus dem Suchindex zurück.

using Azure;
using Azure.Core.Serialization;
using Azure.Search.Documents;
using Azure.Search.Documents.Models;
using Microsoft.Azure.Functions.Worker;
using Microsoft.Azure.Functions.Worker.Http;
using Microsoft.Extensions.Logging;
using System.Net;
using System.Text.Json;
using WebSearch.Models;

namespace WebSearch.Function
{
    public class Lookup
    {
        private static string searchApiKey = Environment.GetEnvironmentVariable("SearchApiKey", EnvironmentVariableTarget.Process);
        private static string searchServiceName = Environment.GetEnvironmentVariable("SearchServiceName", EnvironmentVariableTarget.Process);
        private static string searchIndexName = Environment.GetEnvironmentVariable("SearchIndexName", EnvironmentVariableTarget.Process) ?? "good-books";

        private readonly ILogger<Lookup> _logger;

        public Lookup(ILogger<Lookup> logger)
        {
            _logger = logger;
        }


        [Function("lookup")]
        public async Task<HttpResponseData> RunAsync(
            [HttpTrigger(AuthorizationLevel.Anonymous, "get", "post")] HttpRequestData req, 
            FunctionContext executionContext)
        {

            // Get Document Id
            var query = System.Web.HttpUtility.ParseQueryString(req.Url.Query);
            string documentId = query["id"].ToString();

            // Azure AI Search 
            Uri serviceEndpoint = new($"https://{searchServiceName}.search.windows.net/");

            SearchClient searchClient = new(

                serviceEndpoint,
                searchIndexName,
                new AzureKeyCredential(searchApiKey)
            );

            var getDocumentResponse = await searchClient.GetDocumentAsync<SearchDocument>(documentId);

            // Data to return 
            var output = new LookupOutput
            {
                Document = getDocumentResponse.Value
            };

            var response = req.CreateResponse(HttpStatusCode.Found);
            response.Headers.Add("Content-Type", "application/json; charset=utf-8");

            // Serialize data
            var serializer = new JsonObjectSerializer(
                new JsonSerializerOptions(JsonSerializerDefaults.Web));
            await response.WriteAsJsonAsync(output, serializer);

            return response;
        }
    }
}

Client: Abrufen eines bestimmten Dokuments

Diese Funktions-API wird in der React-App unter \client\src\pages\Details\Detail.js im Rahmen der Komponenteninitialisierung aufgerufen:

import React, { useState, useEffect } from "react";
import { useParams } from 'react-router-dom';
import Rating from '@mui/material/Rating';
import CircularProgress from '@mui/material/CircularProgress';
import axios from 'axios';

import "./Details.css";

export default function Details() {

  let { id } = useParams();
  const [document, setDocument] = useState({});
  const [selectedTab, setTab] = useState(0);
  const [isLoading, setIsLoading] = useState(true);

  useEffect(() => {
    setIsLoading(true);
    // console.log(id);
    axios.get('/api/lookup?id=' + id)
      .then(response => {
        console.log(JSON.stringify(response.data))
        const doc = response.data.document;
        setDocument(doc);
        setIsLoading(false);
      })
      .catch(error => {
        console.log(error);
        setIsLoading(false);
      });

  }, [id]);

  // View default is loading with no active tab
  let detailsBody = (<CircularProgress />),
      resultStyle = "nav-link",
      rawStyle    = "nav-link";

  if (!isLoading && document) {
    // View result
    if (selectedTab === 0) {
      resultStyle += " active";
      detailsBody = (
        <div className="card-body">
          <h5 className="card-title">{document.original_title}</h5>
          <img className="image" src={document.image_url} alt="Book cover"></img>
          <p className="card-text">{document.authors?.join('; ')} - {document.original_publication_year}</p>
          <p className="card-text">ISBN {document.isbn}</p>
          <Rating name="half-rating-read" value={parseInt(document.average_rating)} precision={0.1} readOnly></Rating>
          <p className="card-text">{document.ratings_count} Ratings</p>
        </div>
      );
    }

    // View raw data
    else {
      rawStyle += " active";
      detailsBody = (
        <div className="card-body text-left">
          <pre><code>
            {JSON.stringify(document, null, 2)}
          </code></pre>
        </div>
      );
    }
  }

  return (
    <main className="main main--details container fluid">
      <div className="card text-center result-container">
        <div className="card-header">
          <ul className="nav nav-tabs card-header-tabs">
              <li className="nav-item"><button className={resultStyle} onClick={() => setTab(0)}>Result</button></li>
              <li className="nav-item"><button className={rawStyle} onClick={() => setTab(1)}>Raw Data</button></li>
          </ul>
        </div>
        {detailsBody}
      </div>
    </main>
  );
}

C#-Modelle zur Unterstützung der Funktions-App

Die folgenden Modelle werden verwendet, um die Funktionen in dieser App zu unterstützen:

using Azure.Search.Documents.Models;
using System.Text.Json.Serialization;

namespace WebSearch.Models
{
    public class RequestBodyLookUp
    {
        [JsonPropertyName("id")]
        public string Id { get; set; }
    }

    public class RequestBodySuggest
    {
        [JsonPropertyName("q")]
        public string SearchText { get; set; }

        [JsonPropertyName("top")]
        public int Size { get; set; }

        [JsonPropertyName("suggester")]
        public string SuggesterName { get; set; }
    }

    public class RequestBodySearch
    {
        [JsonPropertyName("q")]
        public string SearchText { get; set; }

        [JsonPropertyName("skip")]
        public int Skip { get; set; }

        [JsonPropertyName("top")]
        public int Size { get; set; }

        [JsonPropertyName("filters")]
        public List<SearchFilter> Filters { get; set; }
    }

    public class SearchFilter
    {
        public string field { get; set; }
        public string value { get; set; }
    }

    public class FacetValue
    {
        public string value { get; set; }
        public long? count { get; set; }
    }

    class SearchOutput
    {
        [JsonPropertyName("count")]
        public long? Count { get; set; }
        [JsonPropertyName("results")]
        public List<SearchResult<SearchDocument>> Results { get; set; }
        [JsonPropertyName("facets")]
        public Dictionary<String, IList<FacetValue>> Facets { get; set; }
    }
    class LookupOutput
    {
        [JsonPropertyName("document")]
        public SearchDocument Document { get; set; }
    }
    public class BookModel
    {
        public string id { get; set; }
        public decimal? goodreads_book_id { get; set; }
        public decimal? best_book_id { get; set; }
        public decimal? work_id { get; set; }
        public decimal? books_count { get; set; }
        public string isbn { get; set; }
        public string isbn13 { get; set; }
        public string[] authors { get; set; }
        public decimal? original_publication_year { get; set; }
        public string original_title { get; set; }
        public string title { get; set; }
        public string language_code { get; set; }
        public double? average_rating { get; set; }
        public decimal? ratings_count { get; set; }
        public decimal? work_ratings_count { get; set; }
        public decimal? work_text_reviews_count { get; set; }
        public decimal? ratings_1 { get; set; }
        public decimal? ratings_2 { get; set; }
        public decimal? ratings_3 { get; set; }
        public decimal? ratings_4 { get; set; }
        public decimal? ratings_5 { get; set; }
        public string image_url { get; set; }
        public string small_image_url { get; set; }
    }
}

Nächste Schritte

Weitere Informationen zur Entwicklung mit Azure KI-Suche finden Sie im nächsten Tutorial zur Indizierung:

• Tutorial: Indizieren von Azure SQL-Daten mithilfe des .NET SDK