SqlConnection throws undocumented ArgumentException

[jzabroski]

https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlconnection.-ctor?view=netframework-4.8

If Application Name passed in is > 128 characters, SqlConnection constructor throws an exception. Interestingly, SqlConnectionStringBuilder class allows passing into it an Application Name > 128 characters.

var connectionString = $"Data Source=.;Initial Catalog=master;Integrated Security=true;Application Name={string.Join(string.Empty, Enumerable.Repeat("_", 129))}";
var connectionStringBuilder = new SqlConnectionStringBulder(connectionString);
using (var sqlConn = new SqlConnection(connectionStringBuilder.ToString())
{
	
}

Error message:

The value's length for key 'application name' exceeds it's limit of '128'.

Stack trace:

at System.Data.SqlClient.SqlConnectionString.ValidateValueLength(String value, Int32 limit, String key)
   at System.Data.SqlClient.SqlConnectionString..ctor(String connectionString)
   at System.Data.SqlClient.SqlConnectionFactory.CreateConnectionOptions(String connectionString, DbConnectionOptions previous)
   at System.Data.ProviderBase.DbConnectionFactory.GetConnectionPoolGroup(DbConnectionPoolKey key, DbConnectionPoolGroupOptions poolOptions, DbConnectionOptions& userConnectionOptions) 
   at System.Data.SqlClient.SqlConnection.ConnectionString_Set(DbConnectionPoolKey key)
   at System.Data.SqlClient.SqlConnection.set_ConnectionString(String value)
   at System.Data.SqlClient.SqlConnection..ctor(String connectionString, SqlCredential credential)
   at System.Data.SqlClient.SqlConnection..ctor(String connectionString)
   at UserQuery.RunUserAuthoredQuery() in C:\Users\john.zabroski\AppData\Local\Temp\LINQPad5\_pogoghlc\query_fnlgxf.cs:line 35
   at LINQPad.ExecutionModel.ClrQueryRunner.Run()
   at LINQPad.ExecutionModel.Server.RunQuery(QueryRunner runner)
   at LINQPad.ExecutionModel.Server.StartQuery(QueryRunner runner)
   at LINQPad.ExecutionModel.Server.<>c__DisplayClass153_0.<ExecuteClrQuery>b__0()
   at LINQPad.ExecutionModel.Server.SingleThreadExecuter.Work()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

[mairaw]

Thanks @jzabroski for your feedback. I'm adding this to our backlog but we can also accept community PRs.

@ajcvickers,@cheenamalhotra, @David-Engel to confirm the difference in behavior and if that's expected.

[David-Engel]

The maximum length of an Application Name in the connection string is documented on the SqlConnection.ConnectionString Property page:
https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlconnection.connectionstring?view=netframework-4.8#remarks

[jzabroski]

@David-Engel Correct, but the path through the system here is not the ConnectionString property, but the constructor taking a raw string value. Note, the SqlConnectionStringBuilder.ToString() method does not throw the exception in my example, and it's the constructor that throws the exception.

Thanks for your patience!

Tagging subscribers to this area: @cheenamalhotra, @David-Engel
See info in area-owners.md if you want to be subscribed.

Issue Details

---

https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlconnection.-ctor?view=netframework-4.8

If Application Name passed in is > 128 characters, SqlConnection constructor throws an exception. Interestingly, SqlConnectionStringBuilder class allows passing into it an Application Name > 128 characters.

var connectionString = $"Data Source=.;Initial Catalog=master;Integrated Security=true;Application Name={string.Join(string.Empty, Enumerable.Repeat("_", 129))}";
var connectionStringBuilder = new SqlConnectionStringBulder(connectionString);
using (var sqlConn = new SqlConnection(connectionStringBuilder.ToString())
{
	
}

Error message:

The value's length for key 'application name' exceeds it's limit of '128'.

Stack trace:

at System.Data.SqlClient.SqlConnectionString.ValidateValueLength(String value, Int32 limit, String key)
   at System.Data.SqlClient.SqlConnectionString..ctor(String connectionString)
   at System.Data.SqlClient.SqlConnectionFactory.CreateConnectionOptions(String connectionString, DbConnectionOptions previous)
   at System.Data.ProviderBase.DbConnectionFactory.GetConnectionPoolGroup(DbConnectionPoolKey key, DbConnectionPoolGroupOptions poolOptions, DbConnectionOptions& userConnectionOptions) 
   at System.Data.SqlClient.SqlConnection.ConnectionString_Set(DbConnectionPoolKey key)
   at System.Data.SqlClient.SqlConnection.set_ConnectionString(String value)
   at System.Data.SqlClient.SqlConnection..ctor(String connectionString, SqlCredential credential)
   at System.Data.SqlClient.SqlConnection..ctor(String connectionString)
   at UserQuery.RunUserAuthoredQuery() in C:\Users\john.zabroski\AppData\Local\Temp\LINQPad5\_pogoghlc\query_fnlgxf.cs:line 35
   at LINQPad.ExecutionModel.ClrQueryRunner.Run()
   at LINQPad.ExecutionModel.Server.RunQuery(QueryRunner runner)
   at LINQPad.ExecutionModel.Server.StartQuery(QueryRunner runner)
   at LINQPad.ExecutionModel.Server.<>c__DisplayClass153_0.<ExecuteClrQuery>b__0()
   at LINQPad.ExecutionModel.Server.SingleThreadExecuter.Work()
   at System.Threading.ThreadHelper.ThreadStart_Context(Object state)
   at System.Threading.ExecutionContext.RunInternal(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state, Boolean preserveSyncCtx)
   at System.Threading.ExecutionContext.Run(ExecutionContext executionContext, ContextCallback callback, Object state)
   at System.Threading.ThreadHelper.ThreadStart()

Author:	jzabroski
Assignees:	-
Labels:	Pri2, doc-enhancement, up-for-grabs, Pri3, area-System.Data.SqlClient
Milestone:	Backlog

[jzabroski]

@David-Engel It looks like you did the work related to this task in dotnet/SqlClient#435, but I don't see it reflected where I would expect: https://docs.microsoft.com/en-us/dotnet/api/system.data.sqlclient.sqlconnection.-ctor?view=dotnet-plat-ext-6.0#system-data-sqlclient-sqlconnection-ctor(system-string)

Is there something I dont understand? I saw in your comments from 2020 that you were just onboarding and understanding how this works, too. :)

[David-Engel]

Sorry, it looks like this fell through the cracks. The update I made was to ensure the doc update got into the docs for Microsoft.Data.SqlClient (M.D.S):
https://docs.microsoft.com/en-us/dotnet/api/microsoft.data.sqlclient.sqlconnection.-ctor?view=sqlclient-dotnet-standard-4.0#microsoft-data-sqlclient-sqlconnection-ctor(system-string)

System.Data.SqlClient isn't under active development. M.D.S is the latest SqlClient. But I can submit the same doc change for System.Data.SqlClient.