Merge pull request #278 from HicServices/feature/db-enumeration

Feature/db enumeration

CHANGELOG.md

@@ -4,6 +4,12 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [Unreleased]
+
+- Fix bug in PostgreSQL boolean handling (use booleans, not BIT)
+- Fix bug in PostgreSQL where database listing failed if a database named 'postgres' was not present
+- Make database enumeration an Enumerable not an array
+
 ## [3.2.1] - 2024-03-11
 
 - Add Setter for DiscoveredDatabaseHelper Create Database Timeout

FAnsiSql/Discovery/DiscoveredServerHelper.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Collections.Generic;
 using System.Data.Common;
+using System.Linq;
 using System.Text.RegularExpressions;
 using System.Threading;
 using FAnsi.Connections;
@@ -105,9 +106,9 @@ public virtual DbConnectionStringBuilder ChangeDatabase(DbConnectionStringBuilde
     }
 
     public abstract IEnumerable<string> ListDatabases(DbConnectionStringBuilder builder);
-    public abstract string[] ListDatabases(DbConnection con);
+    public abstract IEnumerable<string> ListDatabases(DbConnection con);
 
-    public string[] ListDatabasesAsync(DbConnectionStringBuilder builder, CancellationToken token)
+    public IAsyncEnumerable<string> ListDatabasesAsync(DbConnectionStringBuilder builder, CancellationToken token)
     {
         //list the database on the server
         using var con = GetConnection(builder);
@@ -116,7 +117,7 @@ public string[] ListDatabasesAsync(DbConnectionStringBuilder builder, Cancellati
         var openTask = con.OpenAsync(token);
         openTask.Wait(token);
 
-        return ListDatabases(con);
+        return ListDatabases(con).ToAsyncEnumerable();
     }
 
     public abstract DbConnectionStringBuilder EnableAsync(DbConnectionStringBuilder builder);

FAnsiSql/Discovery/IDiscoveredServerHelper.cs

@@ -44,7 +44,8 @@ public interface IDiscoveredServerHelper
     DbConnectionStringBuilder EnableAsync(DbConnectionStringBuilder builder);
 
     IEnumerable<string> ListDatabases(DbConnectionStringBuilder builder);
-    string[] ListDatabasesAsync(DbConnectionStringBuilder builder, CancellationToken token);
+    IEnumerable<string> ListDatabases(DbConnection con);
+    IAsyncEnumerable<string> ListDatabasesAsync(DbConnectionStringBuilder builder, CancellationToken token);
 
     IDiscoveredDatabaseHelper GetDatabaseHelper();
     IQuerySyntaxHelper GetQuerySyntaxHelper();

FAnsiSql/FAnsi.csproj

@@ -44,9 +44,10 @@
     <PackageReference Include="MySqlConnector" Version="2.3.7" />
     <PackageReference Include="Npgsql" Version="8.0.3" />
     <PackageReference Include="Oracle.ManagedDataAccess.Core" Version="23.4.0" />
+    <PackageReference Include="System.Linq.Async" Version="6.0.1" />
   </ItemGroup>
   <ItemGroup>
-    <None Include="..\README.md" Pack="true" PackagePath="\"/>
+    <None Include="..\README.md" Pack="true" PackagePath="\" />
   </ItemGroup>
   <ItemGroup>
     <Compile Update="FAnsiStrings.Designer.cs">

FAnsiSql/Implementations/MicrosoftSQL/MicrosoftSQLServerHelper.cs

@@ -67,20 +67,15 @@ public override IEnumerable<string> ListDatabases(DbConnectionStringBuilder buil
 
         using var con = new SqlConnection(b.ConnectionString);
         con.Open();
-        return ListDatabases(con);
+        foreach (var listDatabase in ListDatabases(con)) yield return listDatabase;
     }
 
-    public override string[] ListDatabases(DbConnection con)
+    public override IEnumerable<string> ListDatabases(DbConnection con)
     {
-        var databases = new List<string>();
-
-        using (var cmd = GetCommand("select name [Database] from master..sysdatabases", con))
-        using (var r = cmd.ExecuteReader())
-            while (r.Read())
-                databases.Add((string)r["Database"]);
-
-        con.Close();
-        return [.. databases];
+        using var cmd = GetCommand("select name [Database] from master..sysdatabases", con);
+        using var r = cmd.ExecuteReader();
+        while (r.Read())
+            yield return (string)r["Database"];
     }
 
     public override DbConnectionStringBuilder EnableAsync(DbConnectionStringBuilder builder)

FAnsiSql/Implementations/MySql/MySqlServerHelper.cs

@@ -107,16 +107,14 @@ public override IEnumerable<string> ListDatabases(DbConnectionStringBuilder buil
 
         using var con = new MySqlConnection(b.ConnectionString);
         con.Open();
-        return ListDatabases(con);
+        foreach (var listDatabase in ListDatabases(con)) yield return listDatabase;
     }
-    public override string[] ListDatabases(DbConnection con)
-    {
-        var databases = new List<string>();
 
+    public override IEnumerable<string> ListDatabases(DbConnection con)
+    {
         using var cmd = GetCommand("show databases;", con);
         using var r = cmd.ExecuteReader();
         while (r.Read())
-            databases.Add((string)r["Database"]);
-        return [.. databases];
+            yield return (string)r["Database"];
     }
 }

FAnsiSql/Implementations/Oracle/OracleServerHelper.cs

@@ -105,7 +105,7 @@ public override void CreateDatabase(DbConnectionStringBuilder builder, IHasRunti
     public override Version GetVersion(DiscoveredServer server)
     {
         using var tcon = server.GetConnection();
-        if (tcon is not OracleConnection con) throw new ArgumentException("Oracle helped called on non-Oracle server",nameof(server));
+        if (tcon is not OracleConnection con) throw new ArgumentException("Oracle helper called on non-Oracle server",nameof(server));
 
         con.UseHourOffsetForUnsupportedTimezone = true;
         con.Open();
@@ -120,18 +120,14 @@ public override IEnumerable<string> ListDatabases(DbConnectionStringBuilder buil
         using var con = new OracleConnection(builder.ConnectionString);
         con.UseHourOffsetForUnsupportedTimezone = true;
         con.Open();
-        return ListDatabases(con);
+        foreach (var listDatabase in ListDatabases(con)) yield return listDatabase;
     }
 
-    public override string[] ListDatabases(DbConnection con)
+    public override IEnumerable<string> ListDatabases(DbConnection con)
     {
-        var databases = new List<string>();
-
-        using(var cmd = GetCommand("select * from all_users", con)) //already comes as single column called Database
-        using (var r = cmd.ExecuteReader())
-            while (r.Read())
-                databases.Add((string) r["username"]);
-
-        return [.. databases];
+        using var cmd = GetCommand("select * from all_users", con);
+        using var r = cmd.ExecuteReader();
+        while (r.Read())
+            yield return (string)r["username"];
     }
 }

FAnsiSql/Implementations/PostgreSql/PostgreSqlServerHelper.cs

@@ -66,26 +66,21 @@ public override IEnumerable<string> ListDatabases(DbConnectionStringBuilder buil
         //create a copy so as not to corrupt the original
         var b = new NpgsqlConnectionStringBuilder(builder.ConnectionString)
         {
-            Database = "postgres",
+            Database = null,
             Timeout = 5
         };
 
         using var con = new NpgsqlConnection(b.ConnectionString);
         con.Open();
-        return ListDatabases(con);
+        foreach (var listDatabase in ListDatabases(con)) yield return listDatabase;
     }
 
-    public override string[] ListDatabases(DbConnection con)
+    public override IEnumerable<string> ListDatabases(DbConnection con)
     {
-        var databases = new List<string>();
-
-        using(var cmd = GetCommand("SELECT datname FROM pg_database;", con))
-        using(var r = cmd.ExecuteReader())
-            while (r.Read())
-                databases.Add((string) r["datname"]);
-
-        con.Close();
-        return [.. databases];
+        using var cmd = GetCommand("SELECT datname FROM pg_database;", con);
+        using var r = cmd.ExecuteReader();
+        while (r.Read())
+            yield return (string)r["datname"];
     }
 
     public override DbCommand GetCommand(string s, DbConnection con, DbTransaction? transaction = null) => new NpgsqlCommand(s, (NpgsqlConnection)

Packages.md

@@ -15,3 +15,4 @@
 | Oracle.ManagedDataAccess.Core  | Closed Source | [OTNLA](https://www.oracle.com/downloads/licenses/distribution-license.html) | Enables interaction with Oracle databases |
 | HIC.TypeGuesser | [GitHub](https://github.com/HicServices/TypeGuesser) | [MIT](https://opensource.org/licenses/MIT)| Allows picking system Types for untyped strings e.g. `"12.3"`| |
 | Npgsql | [GitHub](https://github.com/npgsql/npgsql) | [PostgreSQL](https://github.com/npgsql/npgsql/blob/dev/LICENSE)| Enables interaction with Postgres databases  | |
+| System.Linq.Async | [GitHub](https://github.com/dotnet/reactive) | [MIT](https://opensource.org/licenses/MIT) | Adds async support to LINQ | |