Reorganize SQLite data files

- Add episode data structure (#9)
- Add fields for chapters (#6) and transcripts (#8)
- Add fields for medium (#3), funding (#7), and GUID (#4)
- Fix RethinkDB restore problems (#10)
- Save custom feeds in SQLite (#11)

src/MyWebLog.Data/SQLite/SQLiteWebLogUserData.fs

@@ -0,0 +1,121 @@
+namespace MyWebLog.Data.SQLite
+
+open Microsoft.Data.Sqlite
+open MyWebLog
+open MyWebLog.Data
+
+/// SQLite myWebLog user data implementation        
+type SQLiteWebLogUserData (conn : SqliteConnection) =
+    
+    // SUPPORT FUNCTIONS
+
+    /// Add parameters for web log user INSERT or UPDATE statements
+    let addWebLogUserParameters (cmd : SqliteCommand) (user : WebLogUser) =
+        [ cmd.Parameters.AddWithValue ("@id", WebLogUserId.toString user.id)
+          cmd.Parameters.AddWithValue ("@webLogId", WebLogId.toString user.webLogId)
+          cmd.Parameters.AddWithValue ("@userName", user.userName)
+          cmd.Parameters.AddWithValue ("@firstName", user.firstName)
+          cmd.Parameters.AddWithValue ("@lastName", user.lastName)
+          cmd.Parameters.AddWithValue ("@preferredName", user.preferredName)
+          cmd.Parameters.AddWithValue ("@passwordHash", user.passwordHash)
+          cmd.Parameters.AddWithValue ("@salt", user.salt)
+          cmd.Parameters.AddWithValue ("@url", maybe user.url)
+          cmd.Parameters.AddWithValue ("@authorizationLevel", AuthorizationLevel.toString user.authorizationLevel)
+        ] |> ignore
+    
+    // IMPLEMENTATION FUNCTIONS
+    
+    /// Add a user
+    let add user = backgroundTask {
+        use cmd = conn.CreateCommand ()
+        cmd.CommandText <-
+            """INSERT INTO web_log_user (
+                   id, web_log_id, user_name, first_name, last_name, preferred_name, password_hash, salt,
+                   url, authorization_level
+               ) VALUES (
+                   @id, @webLogId, @userName, @firstName, @lastName, @preferredName, @passwordHash, @salt,
+                   @url, @authorizationLevel
+               )"""
+        addWebLogUserParameters cmd user
+        do! write cmd
+    }
+    
+    /// Find a user by their e-mail address for the given web log
+    let findByEmail (email : string) webLogId = backgroundTask {
+        use cmd = conn.CreateCommand ()
+        cmd.CommandText <-
+            "SELECT * FROM web_log_user WHERE web_log_id = @webLogId AND user_name = @userName"
+        addWebLogId cmd webLogId
+        cmd.Parameters.AddWithValue ("@userName", email) |> ignore
+        use! rdr = cmd.ExecuteReaderAsync ()
+        return if rdr.Read () then Some (Map.toWebLogUser rdr) else None
+    }
+    
+    /// Find a user by their ID for the given web log
+    let findById userId webLogId = backgroundTask {
+        use cmd = conn.CreateCommand ()
+        cmd.CommandText <- "SELECT * FROM web_log_user WHERE id = @id"
+        cmd.Parameters.AddWithValue ("@id", WebLogUserId.toString userId) |> ignore
+        use! rdr = cmd.ExecuteReaderAsync ()
+        return Helpers.verifyWebLog<WebLogUser> webLogId (fun u -> u.webLogId) Map.toWebLogUser rdr 
+    }
+    
+    /// Get all users for the given web log
+    let findByWebLog webLogId = backgroundTask {
+        use cmd = conn.CreateCommand ()
+        cmd.CommandText <- "SELECT * FROM web_log_user WHERE web_log_id = @webLogId"
+        addWebLogId cmd webLogId
+        use! rdr = cmd.ExecuteReaderAsync ()
+        return toList Map.toWebLogUser rdr
+    }
+    
+    /// Find the names of users by their IDs for the given web log
+    let findNames webLogId userIds = backgroundTask {
+        use cmd = conn.CreateCommand ()
+        cmd.CommandText <- "SELECT * FROM web_log_user WHERE web_log_id = @webLogId AND id IN ("
+        userIds
+        |> List.iteri (fun idx userId ->
+            if idx > 0 then cmd.CommandText <- $"{cmd.CommandText}, "
+            cmd.CommandText <- $"{cmd.CommandText}@id{idx}"
+            cmd.Parameters.AddWithValue ($"@id{idx}", WebLogUserId.toString userId) |> ignore)
+        cmd.CommandText <- $"{cmd.CommandText})"
+        addWebLogId cmd webLogId
+        use! rdr = cmd.ExecuteReaderAsync ()
+        return
+            toList Map.toWebLogUser rdr
+            |> List.map (fun u -> { name = WebLogUserId.toString u.id; value = WebLogUser.displayName u })
+    }
+    
+    /// Restore users from a backup
+    let restore users = backgroundTask {
+        for user in users do
+            do! add user
+    }
+    
+    /// Update a user
+    let update user = backgroundTask {
+        use cmd = conn.CreateCommand ()
+        cmd.CommandText <-
+            """UPDATE web_log_user
+                  SET user_name           = @userName,
+                      first_name          = @firstName,
+                      last_name           = @lastName,
+                      preferred_name      = @preferredName,
+                      password_hash       = @passwordHash,
+                      salt                = @salt,
+                      url                 = @url,
+                      authorization_level = @authorizationLevel
+                WHERE id         = @id
+                  AND web_log_id = @webLogId"""
+        addWebLogUserParameters cmd user
+        do! write cmd
+    }
+    
+    interface IWebLogUserData with
+        member _.add user = add user
+        member _.findByEmail email webLogId = findByEmail email webLogId
+        member _.findById userId webLogId = findById userId webLogId
+        member _.findByWebLog webLogId = findByWebLog webLogId
+        member _.findNames webLogId userIds = findNames webLogId userIds
+        member this.restore users = restore users
+        member _.update user = update user