static void Format(ExceptionWithCapturedContext ctx, StringBuilder sb, int indent)
{
if (ctx == null) return;
string indentStr = IndentString(indent);
string nlIndent = nl + indentStr;
sb.Append(indentStr);
string tmp = ctx.Exception.ToString().Replace("\r\n", nl).Replace(nl, nlIndent);
sb.Append(tmp);
if (ctx.InnerException != null)
{
sb.Append(nlIndent);
sb.Append("Inner:");
sb.Append(nl);
Format(ctx.InnerException, sb, indent + 1);
}
}
async Task<HashedLogIdentifier> LogExceptionRecursively(SqlConnectionContext conn, ExceptionWithCapturedContext ctx, int? parentInstanceID = null)
{
// Create the exTargetSite if it does not exist:
var ts = ctx.TargetSite;
SHA1Hash? exTargetSiteID = null;
Task tskTargetSite = null;
if (ts != null)
{
exTargetSiteID = ts.TargetSiteID;
tskTargetSite = conn.ExecNonQuery(
@"MERGE [dbo].[exTargetSite] WITH (HOLDLOCK) AS target
USING (SELECT @exTargetSiteID) AS source (exTargetSiteID)
ON (target.exTargetSiteID = source.exTargetSiteID)
WHEN NOT MATCHED THEN
INSERT ([exTargetSiteID], [AssemblyName], [TypeName], [MethodName], [ILOffset], [FileName], [FileLineNumber], [FileColumnNumber])
VALUES (@exTargetSiteID, @AssemblyName, @TypeName , @MethodName , @ILOffset , @FileName , @FileLineNumber , @FileColumnNumber );",
prms =>
prms.AddInParamSHA1("@exTargetSiteID", exTargetSiteID.GetValueOrDefault())
.AddInParamSize("@AssemblyName", SqlDbType.NVarChar, 256, ts.AssemblyName)
.AddInParamSize("@TypeName", SqlDbType.NVarChar, 256, ts.TypeName)
.AddInParamSize("@MethodName", SqlDbType.NVarChar, 256, ts.MethodName)
.AddInParam("@ILOffset", SqlDbType.Int, ts.ILOffset)
.AddInParamSize("@FileName", SqlDbType.NVarChar, 256, ts.FileName)
.AddInParam("@FileLineNumber", SqlDbType.Int, ts.FileLineNumber)
.AddInParam("@FileColumnNumber", SqlDbType.Int, ts.FileColumnNumber)
);
}
SHA1Hash? userStateCollectionID = null;
if (ctx.UserState != null)
{
userStateCollectionID = CalcCollectionID(ctx.UserState);
}
// Create the exException record if it does not exist:
var tskGetPolicy = conn.ExecReader(
@"MERGE [dbo].[exException] WITH (HOLDLOCK) AS target
USING (SELECT @exExceptionID) AS source (exExceptionID)
ON (target.exExceptionID = source.exExceptionID)
WHEN NOT MATCHED THEN
INSERT ([exExceptionID], [AssemblyName], [TypeName], [StackTrace], [exTargetSiteID])
VALUES (@exExceptionID, @AssemblyName, @TypeName, @StackTrace, @exTargetSiteID );
SELECT excpol.[LogWebContext], excpol.[LogWebRequestHeaders]
FROM [dbo].[exExceptionPolicy] excpol WITH (NOLOCK)
WHERE excpol.[exExceptionID] = @exExceptionID;",
prms =>
prms.AddInParamSHA1("@exExceptionID", ctx.ExceptionID)
.AddInParamSize("@AssemblyName", SqlDbType.NVarChar, 256, ctx.AssemblyName)
.AddInParamSize("@TypeName", SqlDbType.NVarChar, 256, ctx.TypeName)
.AddInParamSize("@StackTrace", SqlDbType.NVarChar, -1, ctx.StackTrace)
.AddInParamSHA1("@exTargetSiteID", exTargetSiteID),
// Read the SELECT result set into an ExceptionPolicy, or use the default policy:
async dr =>
!await dr.ReadAsync()
? ExceptionPolicy.Default
: new ExceptionPolicy(
logWebContext: dr.GetBoolean(dr.GetOrdinal("LogWebContext")),
logWebRequestHeaders: dr.GetBoolean(dr.GetOrdinal("LogWebRequestHeaders"))
)
);
// Create the exException record if it does not exist:
var exApplicationID = CalcApplicationID(cfg);
var tskApplication = conn.ExecNonQuery(
@"MERGE [dbo].[exApplication] WITH (HOLDLOCK) AS target
USING (SELECT @exApplicationID) AS source (exApplicationID)
ON (target.exApplicationID = source.exApplicationID)
WHEN NOT MATCHED THEN
INSERT ([exApplicationID], [MachineName], [ApplicationName], [EnvironmentName], [ProcessPath])
VALUES (@exApplicationID, @MachineName, @ApplicationName, @EnvironmentName, @ProcessPath );",
prms =>
prms.AddInParamSHA1("@exApplicationID", exApplicationID)
.AddInParamSize("@MachineName", SqlDbType.VarChar, 64, cfg.MachineName)
.AddInParamSize("@ApplicationName", SqlDbType.VarChar, 96, cfg.ApplicationName)
.AddInParamSize("@EnvironmentName", SqlDbType.VarChar, 32, cfg.EnvironmentName)
.AddInParamSize("@ProcessPath", SqlDbType.NVarChar, 256, cfg.ProcessPath)
);
// Create the instance record:
var tskInstance = conn.ExecNonQuery(
@"INSERT INTO [dbo].[exInstance]
([exExceptionID], [exApplicationID], [LoggedTimeUTC], [SequenceNumber], [IsHandled], [ApplicationIdentity], [ParentInstanceID], [CorrelationID], [ManagedThreadId], [UserStateCollectionID], [Message])
VALUES (@exExceptionID, @exApplicationID, @LoggedTimeUTC, @SequenceNumber, @IsHandled, @ApplicationIdentity, @ParentInstanceID, @CorrelationID, @ManagedThreadId, @UserStateCollectionID, @Message );
SET @exInstanceID = SCOPE_IDENTITY();",
prms =>
prms.AddOutParam("@exInstanceID", SqlDbType.Int)
.AddInParamSHA1("@exExceptionID", ctx.ExceptionID)
.AddInParamSHA1("@exApplicationID", exApplicationID)
.AddInParam("@LoggedTimeUTC", SqlDbType.DateTime2, ctx.LoggedTimeUTC)
.AddInParam("@SequenceNumber", SqlDbType.Int, ctx.SequenceNumber)
.AddInParam("@IsHandled", SqlDbType.Bit, ctx.IsHandled)
.AddInParamSize("@ApplicationIdentity", SqlDbType.NVarChar, 128, cfg.ApplicationIdentity)
.AddInParam("@ParentInstanceID", SqlDbType.Int, parentInstanceID)
.AddInParam("@CorrelationID", SqlDbType.UniqueIdentifier, ctx.CorrelationID)
.AddInParam("@ManagedThreadId", SqlDbType.Int, ctx.ManagedThreadID)
.AddInParamSHA1("@UserStateCollectionID", userStateCollectionID)
.AddInParamSize("@Message", SqlDbType.NVarChar, 256, ctx.Exception.Message),
(prms, rc) =>
{
return (int)prms["@exInstanceID"].Value;
}
);
// Await the exInstance record creation:
int exInstanceID = await tskInstance;
// Await the exception policy result:
var policy = await tskGetPolicy;
// If logging the web context is enabled and we have a web context to work with, log it:
Task tskLoggingWeb = null;
if (policy.LogWebContext && ctx.CapturedHttpContext != null)
{
tskLoggingWeb = LogWebContext(conn, policy, ctx, exInstanceID);
}
// Log the UserState collection:
if (userStateCollectionID != null)
await LogCollection(conn, userStateCollectionID.Value, ctx.UserState);
// Wait for any outstanding logging tasks:
if (tskLoggingWeb != null) await tskLoggingWeb;
if (tskTargetSite != null) await tskTargetSite;
await tskApplication;
// Recursively log inner exceptions:
var inner = ctx.InnerException;
if (inner != null)
// Return the inner-most exInstanceID because you can easily drill down through the ParentInstanceID columns to reach the root level.
return await LogExceptionRecursively(conn, inner, exInstanceID);
return new HashedLogIdentifier(ctx.ExceptionID, exInstanceID);
}
async Task LogWebContext(SqlConnectionContext conn, ExceptionPolicy policy, ExceptionWithCapturedContext ctx, int exInstanceID)
{
var http = ctx.CapturedHttpContext;
var host = ctx.WebHostingContext;
// We require both HTTP and Host context:
if (http == null || host == null)
return;
// Try to get the authenticated user for the HTTP context:
string authUserName = null;
if (http.User != null && http.User.Identity != null)
authUserName = http.User.Identity.Name;
// Compute the IDs:
var requestURLQueryID = CalcURLQueryID(http.Url);
var referrerURLQueryID = http.UrlReferrer == null ? (SHA1Hash?)null : CalcURLQueryID(http.UrlReferrer);
var exWebApplicationID = CalcWebApplicationID(host);
// Log the web application details:
var tskWebApplication = conn.ExecNonQuery(
@"MERGE [dbo].[exWebApplication] WITH (HOLDLOCK) AS target
USING (SELECT @exWebApplicationID) AS source (exWebApplicationID)
ON (target.exWebApplicationID = source.exWebApplicationID)
WHEN NOT MATCHED THEN
INSERT ([exWebApplicationID], [MachineName], [ApplicationID], [PhysicalPath], [VirtualPath], [SiteName])
VALUES (@exWebApplicationID, @MachineName, @ApplicationID, @PhysicalPath, @VirtualPath, @SiteName );",
prms =>
prms.AddInParamSHA1("@exWebApplicationID", exWebApplicationID)
.AddInParamSize("@MachineName", SqlDbType.NVarChar, 96, host.MachineName)
.AddInParamSize("@ApplicationID", SqlDbType.VarChar, 96, host.ApplicationID)
.AddInParamSize("@PhysicalPath", SqlDbType.NVarChar, 256, host.PhysicalPath)
.AddInParamSize("@VirtualPath", SqlDbType.NVarChar, 256, host.VirtualPath)
.AddInParamSize("@SiteName", SqlDbType.VarChar, 96, host.SiteName)
);
// Log the request headers collection, if requested and available:
Task tskCollection = null;
SHA1Hash? exCollectionID = null;
if (policy.LogWebRequestHeaders && http.Headers != null)
{
var tmpDict = new NameValueCollectionDictionary(http.Headers);
// Compute the collection hash (must be done BEFORE `tskContextWeb`):
exCollectionID = CalcCollectionID(tmpDict);
// Store all records for the headers collection:
tskCollection = LogCollection(conn, exCollectionID.Value, tmpDict);
}
// Log the web context:
var tskContextWeb = conn.ExecNonQuery(
@"INSERT INTO [dbo].[exContextWeb]
([exInstanceID], [exWebApplicationID], [AuthenticatedUserName], [HttpVerb], [RequestURLQueryID], [ReferrerURLQueryID], [RequestHeadersCollectionID])
VALUES (@exInstanceID, @exWebApplicationID, @AuthenticatedUserName, @HttpVerb, @RequestURLQueryID, @ReferrerURLQueryID, @RequestHeadersCollectionID );",
prms =>
prms.AddInParam("@exInstanceID", SqlDbType.Int, exInstanceID)
// Hosting environment:
.AddInParamSHA1("@exWebApplicationID", exWebApplicationID)
// Request details:
.AddInParamSize("@AuthenticatedUserName", SqlDbType.VarChar, 96, authUserName)
.AddInParamSize("@HttpVerb", SqlDbType.VarChar, 16, http.HttpMethod)
.AddInParamSHA1("@RequestURLQueryID", requestURLQueryID)
.AddInParamSHA1("@ReferrerURLQueryID", referrerURLQueryID)
.AddInParamSHA1("@RequestHeadersCollectionID", exCollectionID)
);
// Log the URLs:
Task tskRequestURL, tskReferrerURL;
tskRequestURL = LogURLQuery(conn, http.Url);
if (http.UrlReferrer != null)
tskReferrerURL = LogURLQuery(conn, http.UrlReferrer);
else
tskReferrerURL = null;
// Await the completion of the tasks:
await Task.WhenAll(tskRequestURL, tskWebApplication, tskContextWeb);
if (tskReferrerURL != null) await tskReferrerURL;
if (tskCollection != null) await tskCollection;
}
public static string FormatException(ExceptionWithCapturedContext ctx)
{
if (ctx == null) return "(null)";
var sb = new StringBuilder();
Format(ctx, sb, 0);
return sb.ToString();
}
/// <summary>
/// Record the exception to the various database tables.
/// </summary>
/// <param name="ctx"></param>
/// <returns></returns>
async Task<ILogIdentifier> WriteDatabase(ExceptionWithCapturedContext ctx, int? parentInstanceID = null)
{
using (var conn = new SqlConnection(cfg.ConnectionString))
{
bool attempt = true;
if (noConnection) attempt = TryReconnect();
if (!attempt) return null;
try
{
// Open connection and check connectivity:
await conn.OpenAsync();
}
catch (Exception inex)
{
// No connectivity; reset attempt timer:
noConnection = true;
lastConnectAttempt = DateTime.UtcNow;
FailoverWrite(new ExceptionWithCapturedContext(inex, isHandled: true));
return null;
}
if (cfg.IsTransactional)
{
// Transactional logging:
using (var tran = conn.BeginTransaction(IsolationLevel.Snapshot))
{
var connCtx = new SqlConnectionContext(conn, tran);
try
{
var logged = await LogExceptionRecursively(connCtx, ctx, null);
tran.Commit();
return logged;
}
catch (Exception ex)
{
tran.Rollback();
FailoverWrite(new ExceptionWithCapturedContext(ex, isHandled: true));
return null;
}
}
}
else
{
// Non-transactional logging:
var connCtx = new SqlConnectionContext(conn);
var logged = await LogExceptionRecursively(connCtx, ctx, null);
return logged;
}
}
}
/// <summary>
/// The failover case for when nothing seems to be set up as expected.
/// </summary>
/// <param name="ex"></param>
/// <returns></returns>
public void FailoverWrite(ExceptionWithCapturedContext ctx)
{
var sb = new StringBuilder();
Format(ctx, sb, 0);
string output = sb.ToString();
FailoverWriteString(output);
}
/// <summary>
/// Wrapper method to catch and log exceptions thrown by <paramref name="a"/>.
/// </summary>
/// <param name="a">Asynchronous task to catch exceptions from.</param>
/// <param name="isHandled">Whether the exception is explicitly handled or not.</param>
/// <param name="correlationID">A unique identifier to tie two or more exception reports together.</param>
/// <returns></returns>
public async Task HandleExceptions(Func<Task> a, bool isHandled = false, Guid? correlationID = null)
{
ExceptionWithCapturedContext exToLog = null;
try
{
await a();
}
catch (Exception ex)
{
// NOTE(jsd): `await` is not allowed in catch blocks.
exToLog = new ExceptionWithCapturedContext(
ex,
isHandled,
correlationID,
CurrentWebHost,
new CapturedHttpContext(System.Web.HttpContext.Current)
);
}
if (exToLog != null)
{
await Write(exToLog);
}
}
/// <summary>
/// Write the exception to the database.
/// </summary>
/// <returns></returns>
public async Task<ILogIdentifier> Write(ExceptionWithCapturedContext thrown)
{
try
{
return await WriteDatabase(thrown);
}
catch (Exception ourEx)
{
var actual = new ExceptionWithCapturedContext(ourEx, isHandled: true);
var report = new LoggerExceptionWithCapturedContext(actual, thrown);
FailoverWrite(report);
return (ILogIdentifier)null;
}
}
/// <summary>
/// Represents a thrown exception and some context.
/// </summary>
/// <param name="ex">The exception that was thrown.</param>
/// <param name="isHandled">Whether the exception is explicitly handled or not.</param>
/// <param name="correlationID">A unique identifier to tie two or more exception reports together.</param>
/// <param name="webHostingContext">The current web application hosting context, if applicable.</param>
/// <param name="capturedHttpContext">Captured values from the current HTTP context being handled, if applicable.</param>
public ExceptionWithCapturedContext(
Exception ex,
bool isHandled = false,
Guid? correlationID = null,
WebHostingContext webHostingContext = null,
CapturedHttpContext capturedHttpContext = null
)
{
// Check for a WrappedException to pull out custom Exception info:
WrappedException wex = ex as WrappedException;
Exception thrownEx = ex;
if (wex != null)
{
UserState = wex.UserState;
ex = wex.Wrapped;
}
Exception = ex;
IsHandled = isHandled;
CorrelationID = correlationID;
WebHostingContext = webHostingContext;
CapturedHttpContext = capturedHttpContext;
RealStackTrace = new StackTrace(thrownEx, true);
LoggedTimeUTC = DateTime.UtcNow;
ManagedThreadID = Thread.CurrentThread.ManagedThreadId;
SequenceNumber = Interlocked.Increment(ref runningSequenceNumber);
// Capture some details about the exception:
var exType = ex.GetType();
AssemblyName = exType.Assembly.FullName;
TypeName = exType.FullName;
// TODO(jsd): Sanitize embedded file paths in stack trace
StackTrace = thrownEx.StackTrace;
// SHA1 hash the `assemblyName:typeName:stackTrace[:targetSite]`:
string hashableData = String.Concat(AssemblyName, ":", TypeName, ":", StackTrace);
if (RealStackTrace != null && RealStackTrace.FrameCount > 0)
{
// Add in TargetSite data:
TargetSite = new ExceptionTargetSite(RealStackTrace);
hashableData += ":" + TargetSite.GetHashableData();
}
ExceptionID = Hash.SHA1(hashableData);
if (ex.InnerException != null)
InnerException = new ExceptionWithCapturedContext(ex.InnerException, isHandled, correlationID, webHostingContext, capturedHttpContext);
}
internal LoggerExceptionWithCapturedContext(ExceptionWithCapturedContext actual, ExceptionWithCapturedContext symptom)
{
Actual = actual;
Symptom = symptom;
}