private HttpConnection connect()

in org.eclipse.jgit/src/org/eclipse/jgit/transport/TransportHttp.java [622:747]
108 lines of code
30 McCabe index (conditional complexity)

	private HttpConnection connect(String service,
			TransferConfig.ProtocolVersion protocolVersion)
			throws TransportException, NotSupportedException {
		URL u = getServiceURL(service);
		if (HttpAuthMethod.Type.NONE.equals(authMethod.getType())) {
			authMethod = authFromUri(currentUri);
		}
		int authAttempts = 1;
		int redirects = 0;
		Collection<Type> ignoreTypes = null;
		for (;;) {
			try {
				final HttpConnection conn = httpOpen(METHOD_GET, u, AcceptEncoding.GZIP);
				if (useSmartHttp) {
					String exp = "application/x-" + service + "-advertisement"; //$NON-NLS-1$ //$NON-NLS-2$
					conn.setRequestProperty(HDR_ACCEPT, exp + ", */*"); //$NON-NLS-1$
				} else {
					conn.setRequestProperty(HDR_ACCEPT, "*/*"); //$NON-NLS-1$
				}
				if (TransferConfig.ProtocolVersion.V2.equals(protocolVersion)) {
					conn.setRequestProperty(
							GitProtocolConstants.PROTOCOL_HEADER,
							GitProtocolConstants.VERSION_2_REQUEST);
				}
				final int status = HttpSupport.response(conn);
				processResponseCookies(conn);
				switch (status) {
				case HttpConnection.HTTP_OK:
					// Check if HttpConnection did some authentication in the
					// background (e.g Kerberos/SPNEGO).
					// That may not work for streaming requests and jgit
					// explicit authentication would be required
					if (authMethod.getType() == HttpAuthMethod.Type.NONE
							&& conn.getHeaderField(HDR_WWW_AUTHENTICATE) != null)
						authMethod = HttpAuthMethod.scanResponse(conn, ignoreTypes);
					return conn;

				case HttpConnection.HTTP_NOT_FOUND:
					throw createNotFoundException(uri, u,
							conn.getResponseMessage());

				case HttpConnection.HTTP_UNAUTHORIZED:
					authMethod = HttpAuthMethod.scanResponse(conn, ignoreTypes);
					if (authMethod.getType() == HttpAuthMethod.Type.NONE)
						throw new TransportException(uri, MessageFormat.format(
								JGitText.get().authenticationNotSupported, uri));
					CredentialsProvider credentialsProvider = getCredentialsProvider();
					if (credentialsProvider == null)
						throw new TransportException(uri,
								JGitText.get().noCredentialsProvider);
					if (authAttempts > 1)
						credentialsProvider.reset(currentUri);
					if (3 < authAttempts
							|| !authMethod.authorize(currentUri,
									credentialsProvider)) {
						throw new TransportException(uri,
								JGitText.get().notAuthorized,
								TransportException.Status.NOT_AUTHORIZED);
					}
					authAttempts++;
					continue;

				case HttpConnection.HTTP_FORBIDDEN:
					throw new TransportException(uri, MessageFormat.format(
							JGitText.get().serviceNotPermitted, baseUrl,
							service), TransportException.Status.NOT_PERMITTED);

				case HttpConnection.HTTP_MOVED_PERM:
				case HttpConnection.HTTP_MOVED_TEMP:
				case HttpConnection.HTTP_SEE_OTHER:
				case HttpConnection.HTTP_11_MOVED_PERM:
				case HttpConnection.HTTP_11_MOVED_TEMP:
					// SEE_OTHER should actually never be sent by a git server,
					// and in general should occur only on POST requests. But it
					// doesn't hurt to accept it here as a redirect.
					if (http.getFollowRedirects() == HttpRedirectMode.FALSE) {
						throw new TransportException(uri,
								MessageFormat.format(
										JGitText.get().redirectsOff,
										Integer.valueOf(status)));
					}
					URIish newUri = redirect(u,
							conn.getHeaderField(HDR_LOCATION),
							Constants.INFO_REFS, redirects++);
					setURI(newUri);
					u = getServiceURL(service);
					authAttempts = 1;
					break;
				default:
					String err = status + " " + conn.getResponseMessage(); //$NON-NLS-1$
					TransportException.Status trExStatus =
							status == HttpURLConnection.HTTP_BAD_GATEWAY ? TransportException.Status.BAD_GATEWAY : null;
					throw new TransportException(uri, err, trExStatus);
				}
			} catch (NotSupportedException | TransportException e) {
				throw e;
			} catch (InterruptedIOException e) {
				// Timeout!? Don't try other authentication methods.
				throw new TransportException(uri, MessageFormat.format(
						JGitText.get().connectionTimeOut, u.getHost()), e);
			} catch (SocketException e) {
				// Nothing on other end, timeout, connection reset, ...
				throw new TransportException(uri,
						JGitText.get().connectionFailed, e);
			} catch (SSLHandshakeException e) {
				handleSslFailure(e);
				continue; // Re-try
			} catch (IOException e) {
				if (authMethod.getType() != HttpAuthMethod.Type.NONE) {
					if (ignoreTypes == null) {
						ignoreTypes = new HashSet<>();
					}

					ignoreTypes.add(authMethod.getType());

					// reset auth method & attempts for next authentication type
					authMethod = HttpAuthMethod.Type.NONE.method(null);
					authAttempts = 1;

					continue;
				}

				throw new TransportException(uri, MessageFormat.format(JGitText.get().cannotOpenService, service), e);
			}
		}
	}