/// <summary>
/// Queries the given OIDs and returns the value as string or null if the OID is not available.
/// </summary>
/// <param name="lowerLayer">The lower layer engine to extend.</param>
/// <param name="oid">The OID to query.</param>
/// <param name="what">Descriptive text what is being queried. Used for debug/error output</param>
/// <param name="encoding">If not null, will try to detect whether the string is a hex string and then use the given encoding to decode it.</param>
/// <returns>The OID's value as string or null if the OID is not available.</returns>
public static string QueryAsString(this ISnmpLowerLayer lowerLayer, Oid oid, string what, Encoding encoding = null)
{
VbCollection result = lowerLayer.Query(oid);
var retVal = result[oid]?.Value?.ToString();
if (retVal == null)
{
log.Warn($"Querying '{what}' from '{lowerLayer.Address}' as string returned null");
}
if ((encoding != null) && (retVal.Length > 0))
{
bool couldBeHexString = true;
for (int i = 2; i < retVal.Length; i += 3)
{
if (retVal[i] != ' ')
{
couldBeHexString = false;
break;
}
}
if (couldBeHexString)
{
retVal = encoding.GetString(retVal.HexStringToByteArray(' '));
}
}
return(retVal);
}
/// <summary>
/// Queries the given OIDs and returns the value as OID or null if the OID is not available.
/// </summary>
/// <param name="lowerLayer">The lower layer engine to extend.</param>
/// <param name="oid">The OID to query.</param>
/// <param name="what">Descriptive text what is being queried. Used for debug/error output</param>
/// <returns>The OID's value as OID or null if the OID is not available.</returns>
public static Oid QueryAsOid(this ISnmpLowerLayer lowerLayer, Oid oid, string what)
{
VbCollection result = lowerLayer.Query(oid);
var retVal = result[oid]?.Value as Oid;
if (retVal == null)
{
log.Warn($"Querying '{what}' from '{lowerLayer.Address}' as OID returned null");
}
return(retVal);
}
/// <summary>
/// Queries the given OIDs and returns the value as string or null if the OID is not available.
/// </summary>
/// <param name="lowerLayer">The lower layer engine to extend.</param>
/// <param name="oid">The OID to query.</param>
/// <param name="what">Descriptive text what is being queried. Used for debug/error output</param>
/// <returns>The OID's value as int or <see cref="int.MinValue" /> if the OID is not available.</returns>
public static int QueryAsInt(this ISnmpLowerLayer lowerLayer, Oid oid, string what)
{
VbCollection result = lowerLayer.Query(oid);
int retVal = int.MinValue;
if (!(result[oid]?.Value?.TryToInt(out retVal) ?? false))
{
log.Warn($"Querying '{what}' from '{lowerLayer.Address}' as string returned null");
}
return(retVal);
}
/// <summary>
/// Queries the given OIDs and returns the value as <see cref="TimeSpan" /> or null if the OID is not available.
/// </summary>
/// <param name="lowerLayer">The lower layer engine to extend.</param>
/// <param name="oid">The OID to query.</param>
/// <param name="what">Descriptive text what is being queried. Used for debug/error output</param>
/// <returns>The OID's value as <see cref="TimeSpan" /> or null if the OID is not available or cannot be parsed as <see cref="TimeSpan" />.</returns>
public static TimeSpan?QueryAsTimeSpan(this ISnmpLowerLayer lowerLayer, Oid oid, string what)
{
VbCollection result = lowerLayer.Query(oid);
var retVal = result[oid]?.Value as TimeTicks;
if (retVal == null)
{
log.Warn($"Querying '{what}' from '{lowerLayer.Address}' as TimeTicks returned null");
return(null);
}
return(TimeSpan.FromMilliseconds(retVal.Milliseconds));
}
/// <summary>
/// Queries the given OIDs and returns the value as string or null if the OID is not available.
/// </summary>
/// <param name="lowerLayer">The lower layer engine to extend.</param>
/// <param name="oids">The OIDs list to query.</param>
/// <param name="what">Descriptive text what is being queried. Used for debug/error output</param>
/// <returns>The OID's value as int or or <see cref="int.MinValue" /> if the OID is not available.</returns>
public static Dictionary <Oid, int> QueryAsInt(this ISnmpLowerLayer lowerLayer, IEnumerable <Oid> oids, string what)
{
if (oids == null)
{
throw new ArgumentNullException(nameof(oids), "The array of oids to query is null");
}
VbCollection queryResult = lowerLayer.Query(oids);
return(queryResult.ToDictionary(qr => qr.Oid, qr =>
{
int retVal = int.MinValue;
if (!(qr.Value?.TryToInt(out retVal) ?? false))
{
log.Warn($"Querying '{what}' from '{lowerLayer.Address}' as Dictionary<Oid, int>: Conversion to int returned null for response '{qr}'");
}
return retVal;
}));
}
/// <inheritdoc />
public override IDeviceHandler CreateHandler(ISnmpLowerLayer lowerLayer, IQuerierOptions options)
{
if (!this.detectionId.HasValue)
{
var ex = new InvalidOperationException("Cannot perform CreateHandler() without previous and successful call to IsApplicable");
this.CollectException("UbntSnmp: CreateHandler(ISnmpLowerLayer, IQuerierOptions)", ex);
throw ex;
}
try
{
List <Oid> queryList = new List <Oid>();
Oid osVersionOid = null;
if (string.IsNullOrWhiteSpace(this.osDetectedVersion))
{
osVersionOid = OsVersionRootOid + new Oid(new uint[] { this.detectionId.Value });
queryList.Add(osVersionOid);
}
Oid modelOid = null;
if (string.IsNullOrWhiteSpace(this.detectedModel))
{
modelOid = ModelRootOid + new Oid(new uint[] { this.detectionId.Value });
queryList.Add(modelOid);
}
VbCollection osVersionCollection = null;
if (queryList.Count > 0)
{
osVersionCollection = lowerLayer.Query(queryList);
}
string osVersionString = (osVersionOid != null)
? osVersionCollection[osVersionOid].Value.ToString()
: this.osDetectedVersion;
Match match = OsVersionExtractionRegex.Match(osVersionString);
SemanticVersion osVersion = match.Success ? match.Groups[1].Value.ToSemanticVersion() : null;
string model = (modelOid != null)
? osVersionCollection[modelOid].Value.ToString()
: this.detectedModel;
if (string.IsNullOrWhiteSpace(model))
{
var info = $"Model (retrieved using OID '{modelOid}') is null, empty or white-space-only";
log.Warn(info);
var ex = new HamnetSnmpException(info, lowerLayer?.Address?.ToString());
this.CollectException("UbntSnmp: No model", ex);
throw ex;
}
log.Info($"Detected device '{lowerLayer.Address}' as Ubiquiti '{model}' v '{osVersion}'");
DeviceVersion deviceVersion;
IDeviceSpecificOidLookup oidTable = this.ObtainOidTable(model.Trim(), osVersion, out deviceVersion, lowerLayer?.Address);
if (string.IsNullOrWhiteSpace(deviceVersion.HandlerClassName))
{
return((model == AirFiberFakeModelString)
? new UbiquitiAirFiberDeviceHandler(lowerLayer, oidTable, osVersion, model, options) as IDeviceHandler
: new UbiquitiAirOsAbove56DeviceHandler(lowerLayer, oidTable, osVersion, model, options) as IDeviceHandler);
}
else
{
return(this.GetHandlerViaReflection(deviceVersion.HandlerClassName, lowerLayer, oidTable, osVersion, model, options));
}
}
catch (Exception ex)
{
this.CollectException("UbntSnmp: Model detection and OID lookup", ex);
// we want to catch and nest the exception here as the APIs involved are not able to append the infomration for which
// device (i.e. IP address) the exception is for
throw new HamnetSnmpException($"Failed to create handler for Ubiquiti device '{lowerLayer.Address}': {ex.Message}", ex, lowerLayer?.Address?.ToString());
}
}
