public AzureAppConfigurationProvider(ConfigurationClient client, AzureAppConfigurationOptions options, bool optional)
{
_client = client ?? throw new ArgumentNullException(nameof(client));
_options = options ?? throw new ArgumentNullException(nameof(options));
_optional = optional;
IEnumerable <KeyValueWatcher> watchers = options.ChangeWatchers.Union(options.MultiKeyWatchers);
if (watchers.Any())
{
MinCacheExpirationTime = watchers.Min(w => w.CacheExpirationTime);
}
else
{
MinCacheExpirationTime = AzureAppConfigurationRefreshOptions.DefaultCacheExpirationTime;
}
// Enable request tracing if not opt-out
string requestTracingDisabled = null;
try
{
requestTracingDisabled = Environment.GetEnvironmentVariable(RequestTracingConstants.RequestTracingDisabledEnvironmentVariable);
}
catch (SecurityException) { }
_requestTracingEnabled = bool.TryParse(requestTracingDisabled, out bool tracingDisabled) ? !tracingDisabled : true;
if (_requestTracingEnabled)
{
_hostType = TracingUtils.GetHostType();
}
}
/// <summary>
/// An implementation of <see cref="IOfflineCache.Import(AzureAppConfigurationOptions)"/> that retrieves the cached data from the file system.
/// </summary>
public string Import(AzureAppConfigurationOptions options)
{
EnsureOptions(options);
int retry = 0;
while (retry++ <= retryMax)
{
try
{
string data = null, dataHash = null, scopeHash = null;
byte[] bytes = File.ReadAllBytes(_localCachePath);
var reader = new Utf8JsonReader(bytes);
while (reader.Read())
{
if (reader.TokenType == JsonTokenType.PropertyName)
{
switch (reader.GetString())
{
case dataProp:
data = reader.ReadAsString();
break;
case hashProp:
dataHash = reader.ReadAsString();
break;
case scopeProp:
scopeHash = reader.ReadAsString();
break;
default:
return(null);
}
}
}
if ((data != null) && (dataHash != null) && (scopeHash != null))
{
string newScopeHash = CryptoService.GetHash(Encoding.UTF8.GetBytes(_scopeToken), _options.SignKey);
if (string.CompareOrdinal(scopeHash, newScopeHash) == 0)
{
string newDataHash = CryptoService.GetHash(Convert.FromBase64String(data), _options.SignKey);
if (string.CompareOrdinal(dataHash, newDataHash) == 0)
{
return(CryptoService.AESDecrypt(data, _options.Key, _options.IV));
}
}
}
}
catch (IOException ex) when(ex.HResult == ERROR_SHARING_VIOLATION)
{
Task.Delay(new Random().Next(delayRange)).ConfigureAwait(false).GetAwaiter().GetResult();
}
}
return(null);
}
public AzureAppConfigurationSource(Action <AzureAppConfigurationOptions> optionsInitializer, bool optional = false, IConfigurationClientFactory configurationClientFactory = null)
{
_optionsProvider = () => {
var options = new AzureAppConfigurationOptions();
optionsInitializer(options);
return(options);
};
_optional = optional;
_configurationClientFactory = configurationClientFactory ?? new ConfigurationClientFactory();
}
private void EnsureOptions(AzureAppConfigurationOptions azconfigOptions)
{
if (azconfigOptions == null)
{
throw new ArgumentNullException(nameof(azconfigOptions));
}
if (azconfigOptions.ConnectionString == null)
{
throw new InvalidOperationException("An Azure App Configuration connection string is required.");
}
OfflineFileCacheOptions options = _options ?? new OfflineFileCacheOptions();
if ((options.Key == null) || (options.SignKey == null) || (options.IV == null))
{
byte[] secret = Convert.FromBase64String(ConnectionStringParser.Parse(azconfigOptions.ConnectionString, "Secret"));
using (SHA256 sha256 = SHA256.Create())
{
byte[] hash = sha256.ComputeHash(secret);
options.Key = options.Key ?? hash;
options.SignKey = options.SignKey ?? hash;
options.IV = options.IV ?? hash.Take(16).ToArray();
}
}
if (string.IsNullOrEmpty(_scopeToken))
{
//
// The default scope token is the configuration store endpoint combined with all of the key-value filters
string endpoint = ConnectionStringParser.Parse(azconfigOptions.ConnectionString, "Endpoint");
if (string.IsNullOrWhiteSpace(endpoint))
{
throw new InvalidOperationException("Invalid connection string format.");
}
var sb = new StringBuilder($"{endpoint}\0");
foreach (var selector in azconfigOptions.KeyValueSelectors)
{
sb.Append($"{selector.KeyFilter}\0{selector.LabelFilter}\0");
}
_scopeToken = sb.ToString();
}
_options = options;
}
public AzureAppConfigurationProvider(ConfigurationClient client, AzureAppConfigurationOptions options, bool optional)
{
_client = client ?? throw new ArgumentNullException(nameof(client));
_options = options ?? throw new ArgumentNullException(nameof(options));
_optional = optional;
// Enable request tracing if not opt-out
string requestTracingDisabled = null;
try
{
requestTracingDisabled = Environment.GetEnvironmentVariable(RequestTracingConstants.RequestTracingDisabledEnvironmentVariable);
}
catch (SecurityException) { }
_requestTracingEnabled = bool.TryParse(requestTracingDisabled, out bool tracingDisabled) ? !tracingDisabled : true;
if (_requestTracingEnabled)
{
_hostType = TracingUtils.GetHostType();
}
}
/// <summary>
/// An implementation of <see cref="IOfflineCache.Export(AzureAppConfigurationOptions, string)"/> that caches the data in the file system.
/// </summary>
public void Export(AzureAppConfigurationOptions options, string data)
{
EnsureOptions(options);
if ((DateTime.Now - File.GetLastWriteTime(_localCachePath)) > TimeSpan.FromMilliseconds(1000))
{
Task.Run(async() =>
{
string tempFile = Path.Combine(Path.GetDirectoryName(_localCachePath), $"azconfigTemp-{Path.GetRandomFileName()}");
var dataBytes = Encoding.UTF8.GetBytes(data);
var encryptedBytes = CryptoService.AESEncrypt(dataBytes, _options.Key, _options.IV);
var dataHash = CryptoService.GetHash(encryptedBytes, _options.SignKey);
var scopeHash = CryptoService.GetHash(Encoding.UTF8.GetBytes(_scopeToken), _options.SignKey);
using (var fileStream = new FileStream(tempFile, FileMode.Create))
{
using (var memoryStream = new MemoryStream())
{
using (var writer = new Utf8JsonWriter(memoryStream))
{
writer.WriteStartObject();
writer.WriteString(dataProp, Convert.ToBase64String(encryptedBytes));
writer.WriteString(hashProp, dataHash);
writer.WriteString(scopeProp, scopeHash);
writer.WriteEndObject();
}
memoryStream.Position = 0;
memoryStream.CopyTo(fileStream);
fileStream.Flush();
}
}
await this.DoUpdate(tempFile).ConfigureAwait(false);
});
}
}
public IConfigurationProvider Build(IConfigurationBuilder builder)
{
IConfigurationProvider provider = null;
try
{
AzureAppConfigurationOptions options = _optionsProvider();
ConfigurationClient client;
if (options.Client != null)
{
client = options.Client;
}
else if (!string.IsNullOrWhiteSpace(options.ConnectionString))
{
client = _configurationClientFactory.CreateConfigurationClient(options.ConnectionString, options.ClientOptions);
}
else if (options.Endpoint != null && options.Credential != null)
{
client = _configurationClientFactory.CreateConfigurationClient(options.Endpoint, options.Credential, options.ClientOptions);
}
else
{
throw new ArgumentException($"Please call {nameof(AzureAppConfigurationOptions)}.{nameof(AzureAppConfigurationOptions.Connect)} to specify how to connect to Azure App Configuration.");
}
provider = new AzureAppConfigurationProvider(client, options, _optional);
}
catch (InvalidOperationException e)
{
if (!_optional)
{
throw new ArgumentException(e.Message, e);
}
}
return(provider ?? new EmptyConfigurationProvider());
}
