General Planning Implementation tasks of Managing Play List in Chinook

[jthompsonnait]

This task list area will be completed once the implementation plan has been outlined. This area is where one creates the task list that is associated with the milestone. The tasks that are outlined in this area, are the tasks that are counted for the milestone.

• [ ] Create Data Models
  • Create Query Models
  • [ ] Track_FetchTracksBy
  • [ ] PlaylistTrack_FetchPlaylist
  • Create Command Models
  • [ ] PlaylistTrackTRXInput
• [ ] Create Transactional Services (methods)
  • [ ] Add a Track
  • [ ] Remove tracks from playlist
  • [ ] Reorganize playlist tracks
• [ ] #3

[jthompsonnait]

UI Experience

This comment outlines the action that can happen on the forms. Action are in response to the user interacting with the form, pressing button, or controls.

PRG Post Redirect Get

• Using routing parameters {searchType?}/{searchValue?}/{playlistName?}
• PRG clicking the Clear empties bound properties and routing parameters (page only)
• PRG clicking the Fetch will retrieve the existing playlist for the specified playlist name {playlistname?} PlaylistTrackService_FetchPlaylist(...)
• PRG clicking the Fetch Artist tracks or Fetch Album tracks will retrieve the tracks for the indicated search and display in a table using routing parameters {searchtype?}/{searchvalue?} TrackService_FetchTrackBy(...)
• Post/PRG clicking the Add(+) on the track will attempt to add the track to the playlist PlayListTrackService_AddTrack(...)
• rule: unique track on the playlist
• rule: playlist name needs to be unique for the user
• rule: appended track to playlist
• Post/PRG clicking the Remove Tracks will matter to remove 1 or more tracks from the PlaylistTrackService_RemoveTrack(...)
• rule: re-sequence the playlist track numbers leaving no gaps.
• Post/PRG clicking the Move Tracks will attempt to reorganize the order of the playlist: PlaylistTrackService_MoveTracks(...)

  • rule: all tracks require a re-sequence track number
  • rule: track numbers must be greater than 0
  • rule: track numbers must be unique

  • rule: tracks numbers must not introduce holes

    Expected Transactional Form

[jthompsonnait]

Chinook ERD for Transactional Form

[jthompsonnait]

Data Models (CQRS)

The data models are the C# classes that will be coded in the class library project/application (folder: ViewModels) that holds the public data classes in our solution. These classes represent the query class models and the command class models (CQRS)

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Query Models

Artist and Album Tracks fetch (TrackService_FetchTracksBy)

public class TrackSelection
{
    public int TrackId {get; set;}
    public string SongName {get; set;}
    public string AlbumTitle{get; set;}
    public string ArtistName{get; set;}
    public int Milliseconds {get; set;}
    public decimal Price {get; set;}
}

Current Playlist fetch (PlaylistTrackService_FetchPlaylist)

public class PlaylistTrackInfo 
{
    public int TrackId {get; set;}
    public int TrackNumber {get; set;}
    public string SongName {get; set;}
    public int Milliseconds {get; set;}
}

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Command Models

Add Track

No model class, individual parameters

Remove/Move Tracks (shared command model due to the web page handling of BindProperty)

Remove Tracks

for the Remove Tracks functionality, the SelectedTrack and TrackId will be required for transactional processing

Move Tracks (re-sequence playlist)

for the Move Tracks functionality, the TrackId, TrackNumber and TrackInput will be required for transactional processing

public class PlaylistTrackTRX
{
    public bool SelectedTrack {get; set;}
    public int TrackId {get; set;}
    public int TrackNumber {get; set;}
    public int TrackInput {get; set;}
}

[jthompsonnait]

Business Processing Requirements

This comment will describe the various methods that will be used for Commands (CQRS) that alter the database. Queries are read only and require on average no complex processing. You may in another comment outline your query methods. However, commands require business rules, data validation and manipulations of one or more tables and/or records. Therefore, the processing of commands could required extensive logic to be outlined.

include the method signature and a bullet list of processing (pseudo-code)

Add Track

void PlaylistTrackService_AddTrack(string playlistname, string username, int trackid)

• check that the incoming data exists
  • if a problem exists, throw an ArgumentNullException for missing incoming value
• check track exists
  • does not exist, throw an ArgumentException on trackid
• check to see if playlist exists
  • no (new playlist)
  • create a new playlist record
  • set track number to 1
  • yes (appending to existing playlist)
  • check if track already on the playlist (B/R)
    • yes
    • throw an Exception B/R
    • no
    • determine the next track number
• add track to playlist tracks
• check for any errors
  • yes: throw list of all collected exceptions
  • no: save all work to database

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Remove Track

void PlaylistTrackService_RemoveTrack(string playlistname, string username, int trackid)