public static T GetConfigSetting <T>(string key)
{
try
{
var appSetting = ConfigurationManager.AppSettings[key];
if (string.IsNullOrWhiteSpace(appSetting))
{
throw new ConfigurationErrorsException(
string.Format("Helpers.AppSettings: key {0} was null or empty", key));
}
var converter = TypeDescriptor.GetConverter(typeof(T));
return((T)(converter.ConvertFromInvariantString(appSetting)));
}
catch (ConfigurationErrorsException ex)
{
AsLogger.LogWarning("Configuration value was missing from configuration file. Returning default value.", ex);
return(default(T));
}
catch (Exception ex)
{
AsLogger.LogError("Unexpected exception accessing configuration file or data", ex);
throw;
}
}
public static void SetArchivesSpaceHeader(this HttpClient client, string sessionKey)
{
var archivesSpaceHeaderName = "X-ArchivesSpace-Session";
if (client.DefaultRequestHeaders.Contains(archivesSpaceHeaderName))
{
AsLogger.LogDebug("[SetArchivesSpaceHeader] Existing header found, removing from request");
client.DefaultRequestHeaders.Remove(archivesSpaceHeaderName);
}
AsLogger.LogDebug(String.Format("[SetArchivesSpaceHeader] Setting ArchivesSpace Header with name [ {0} ] to value [ {1} ]", archivesSpaceHeaderName, sessionKey));
client.DefaultRequestHeaders.Add(archivesSpaceHeaderName, sessionKey);
}
public bool Login()
{
try
{
LoginAction();
return(true);
}
catch (WebException ex) //Note we're using a webexception since login happens with webclient, everything else with httpclient
{
AsLogger.LogWarning("caught invalid login attempt, returning false. error was: ", ex);
}
return(false);
}
public void Impersonate(string targetUser)
{
if (_canImpersonate)
{
var apiUrl = string.Format("users/{0}/become-user", targetUser);
var responseText = PostActionAsync(apiUrl).Result; //no deadlock b/c configure await is off
var responseJson = JObject.Parse(responseText);
UserData = responseJson["user"].Value <JObject>();
}
else
{
var ex = new InvalidOperationException("user does not have permission to impersonate other users");
AsLogger.LogError(String.Format("user [ {0} ] attempted to impersonate user [ {1} ] but lacks become_user permission in ArchivesSpace", _userCred.Username, targetUser), ex);
}
}
private async Task <string> PostActionAsync(string apiUri, IEnumerable <KeyValuePair <string, string> > postParams)
{
var uri = String.Format("{0}/{1}", _baseUrl, apiUri);
AsLogger.LogDebug(String.Format("Posting to URI: {0}", uri));
var postBody = new FormUrlEncodedContent(postParams);
var response = await _httpClient.PostAsync(uri, postBody).ConfigureAwait(false);
response.EnsureSuccessStatusCode();
var responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
return(responseString);
}
private async Task <string> PostActionAsync(string apiUri)
{
var uri = String.Format("{0}/{1}", _baseUrl, apiUri);
AsLogger.LogDebug(String.Format("Posting to URI: {0}", uri));
var httpContent = new StringContent(""); //Empty, we're just posting to the URI in this method
var response = await _httpClient.PostAsync(uri, httpContent).ConfigureAwait(false);
response.EnsureSuccessStatusCode();
var responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
return(responseString);
}
private void LoginAction()
{
//This can't be async and needs to happen before we set the global request headers of the httpclient field
using (var wc = new WebClient())
{
AsLogger.LogDebug(String.Format("ASpace Login routine starting for user with username [ {0} ]. Current session key is [ {1} ]", _userCred.Username, _sessionKey ?? "null"));
string loginUri = String.Format("{0}/users/{1}/login", _baseUrl, _userCred.Username);
var postParams = new NameValueCollection();
postParams.Add("password", _userCred.Password);
var response = wc.UploadValues(loginUri, postParams);
var responseString = Encoding.UTF8.GetString(response);
var responseJson = JObject.Parse(responseString);
_sessionKey = responseJson["session"].Value <string>();
AsLogger.LogDebug(String.Format("New session key set: [ {0} ]", _sessionKey));
UserData = responseJson["user"].Value <JObject>();
_canImpersonate = UserData.ToString().Contains("become_user");
_httpClient.SetArchivesSpaceHeader(_sessionKey);
}
}
private async Task <HttpResponseMessage> GetActionAsync(string apiUri)
{
//ToDo: Returning a string response is a design flaw in this context since we may want to handle 404s and other errors
//which make sense for the REST API but would blend in with Network Errors if we convert to a string right away.
//Error handling should happen upstream when we're more sure of what the request is about
if (apiUri.StartsWith(@"/"))
{
apiUri = apiUri.TrimStart('/');
}
var uriString = String.Format("{0}/{1}", _baseUrl, apiUri);
AsLogger.LogDebug(String.Format("Requesting URL: {0}", uriString));
AsLogger.LogDebug(String.Format("Current Session Key: [ {0} ]", _sessionKey));
try
{
var response = await _httpClient.GetAsync(uriString).ConfigureAwait(false);
if (response.IsSuccessStatusCode)
{
AsLogger.LogDebug("[GetActionAsync] Request Successful, returning response content");
return(response);
}
else
{
var responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
AsLogger.LogWarning(String.Format("[GetActionAsync] Request did not return a success status code. Code [ {0} : {1} ] Message Body [ {2} ]", (int)response.StatusCode, response.StatusCode, responseString));
return(response);
}
}
catch (HttpRequestException rex)
{
AsLogger.LogError(String.Format("[ArchivesSpaceConnectionHandler.GetActionAsync] API request to [ {0} ] failed. Exception follows.", uriString), rex);
throw;
}
}
public async Task <string> GetAsync(string apiUri)
{
HttpResponseMessage response;
if (string.IsNullOrEmpty(_sessionKey))
{
LoginAction(); //and we're going to let it throw an unauthorized exception if it doesn't work since the user isn't checking first
}
try
{
response = await GetActionAsync(apiUri).ConfigureAwait(false);
response.EnsureSuccessStatusCode();
var responseString = await response.Content.ReadAsStringAsync().ConfigureAwait(false);
return(responseString);
}
catch (HttpRequestException ex)
{
//We are forcing a success code to continue, most likely error is an expired session so try that first
AsLogger.LogError(String.Format("[ArchivesSpaceConnectionHandler.GetAsync] Error getting api resource [ {0} ] - attempting to login and retry", apiUri), ex);
LoginAction();
try
{
response = GetActionAsync(apiUri).Result;
response.EnsureSuccessStatusCode();
var responseString = response.Content.ReadAsStringAsync().Result;
return(responseString);
}
catch (HttpRequestException rex)
{
AsLogger.LogError("[ArchivesSpaceConnectionHandler.GetAsync] Request failed after retrying login. Exception follows.", rex);
throw;
}
}
}
