python/educational-core/student/src/com/jetbrains/edu/learning/stepic/EduStepicClient.java

   1 package com.jetbrains.edu.learning.stepic;
   2
   3 import com.google.gson.FieldNamingPolicy;
   4 import com.google.gson.Gson;
   5 import com.google.gson.GsonBuilder;
   6 import com.intellij.openapi.diagnostic.Logger;
   7 import com.intellij.util.net.HttpConfigurable;
   8 import com.intellij.util.net.ssl.CertificateManager;
   9 import com.jetbrains.edu.learning.StudySerializationUtils;
  10 import org.apache.http.HttpEntity;
  11 import org.apache.http.HttpHost;
  12 import org.apache.http.HttpStatus;
  13 import org.apache.http.StatusLine;
  14 import org.apache.http.client.methods.CloseableHttpResponse;
  15 import org.apache.http.client.methods.HttpGet;
  16 import org.apache.http.impl.DefaultConnectionReuseStrategy;
  17 import org.apache.http.impl.client.CloseableHttpClient;
  18 import org.apache.http.impl.client.HttpClientBuilder;
  19 import org.apache.http.impl.client.HttpClients;
  20 import org.apache.http.util.EntityUtils;
  21 import org.jetbrains.annotations.NotNull;
  22
  23 import javax.net.ssl.SSLContext;
  24 import javax.net.ssl.TrustManager;
  25 import javax.net.ssl.X509TrustManager;
  26 import java.io.IOException;
  27 import java.net.InetSocketAddress;
  28 import java.net.Proxy;
  29 import java.net.URI;
  30 import java.security.KeyManagementException;
  31 import java.security.NoSuchAlgorithmException;
  32 import java.security.SecureRandom;
  33 import java.security.cert.X509Certificate;
  34 import java.util.List;
  35
  36 public class EduStepicClient {
  37   private static final Logger LOG = Logger.getInstance(EduStepicClient.class.getName());
  38   private static CloseableHttpClient ourClient;
  39
  40   private EduStepicClient() {
  41   }
  42
  43   @NotNull
  44   public static CloseableHttpClient getHttpClient() {
  45     if (ourClient == null) {
  46       initializeClient();
  47     }
  48     return ourClient;
  49   }
  50
  51   public static <T> T getFromStepic(String link, final Class<T> container) throws IOException {
  52     return getFromStepic(link, container, getHttpClient());
  53   }
  54
  55   static <T> T getFromStepic(String link, final Class<T> container, @NotNull final CloseableHttpClient client) throws IOException {
  56     if (!link.startsWith("/")) link = "/" + link;
  57     final HttpGet request = new HttpGet(EduStepicNames.STEPIC_API_URL + link);
  58     if (ourClient == null) {
  59       initializeClient();
  60     }
  61
  62     final CloseableHttpResponse response = client.execute(request);
  63     final StatusLine statusLine = response.getStatusLine();
  64     final HttpEntity responseEntity = response.getEntity();
  65     final String responseString = responseEntity != null ? EntityUtils.toString(responseEntity) : "";
  66     EntityUtils.consume(responseEntity);
  67     if (statusLine.getStatusCode() != HttpStatus.SC_OK) {
  68       throw new IOException("Stepic returned non 200 status code " + responseString);
  69     }
  70     return deserializeStepicResponse(container, responseString);
  71   }
  72
  73   static <T> T deserializeStepicResponse(Class<T> container, String responseString) {
  74     Gson gson = new GsonBuilder().registerTypeAdapter(StepicWrappers.StepOptions.class, new StudySerializationUtils.Json.StepicStepOptionsAdapter()).
  75       setDateFormat("yyyy-MM-dd'T'HH:mm:ss'Z'").
  76       setFieldNamingPolicy(FieldNamingPolicy.LOWER_CASE_WITH_UNDERSCORES).create();
  77     return gson.fromJson(responseString, container);
  78   }
  79
  80   private static void initializeClient() {
  81     if (ourClient == null) {
  82       final HttpClientBuilder builder = getBuilder();
  83       ourClient = builder.build();
  84     }
  85   }
  86
  87   @NotNull
  88   private static TrustManager[] trustAllCerts() {
  89     // Create a trust manager that does not validate certificate for this connection
  90     return new TrustManager[]{new X509TrustManager() {
  91       public X509Certificate[] getAcceptedIssuers() {
  92         return null;
  93       }
  94
  95       public void checkClientTrusted(X509Certificate[] certs, String authType) {
  96       }
  97
  98       public void checkServerTrusted(X509Certificate[] certs, String authType) {
  99       }
 100     }};
 101   }
 102
 103   @NotNull
 104   private static HttpClientBuilder getBuilder() {
 105     final HttpClientBuilder builder = HttpClients.custom().setSslcontext(CertificateManager.getInstance().getSslContext()).
 106       setMaxConnPerRoute(100000).setConnectionReuseStrategy(DefaultConnectionReuseStrategy.INSTANCE);
 107
 108     final HttpConfigurable proxyConfigurable = HttpConfigurable.getInstance();
 109     final List<Proxy> proxies = proxyConfigurable.getOnlyBySettingsSelector().select(URI.create(EduStepicNames.STEPIC_URL));
 110     final InetSocketAddress address = proxies.size() > 0 ? (InetSocketAddress)proxies.get(0).address() : null;
 111     if (address != null) {
 112       builder.setProxy(new HttpHost(address.getHostName(), address.getPort()));
 113     }
 114     final TrustManager[] trustAllCerts = trustAllCerts();
 115     try {
 116       SSLContext sslContext = SSLContext.getInstance("TLS");
 117       sslContext.init(null, trustAllCerts, new SecureRandom());
 118       builder.setSslcontext(sslContext);
 119     }
 120     catch (NoSuchAlgorithmException | KeyManagementException e) {
 121       LOG.error(e.getMessage());
 122     }
 123     return builder;
 124   }
 125 }