Question

我试图扩展我在sinatra书中看到的一个例子。我想尝试使用DataMapper，所以我最终得到了这个：

require 'dm-core'
require 'dm-migrations'
require 'rubygems'
require 'sinatra'

configure:development do
    DataMapper.setup(:default, "sqlite3://#{Dir.pwd}/3sbase.db")
    DataMapper.auto_upgrade!
end

class Artist
    include DataMapper::Resource
    property :name, String, :key=>true
    property :born, Integer
    has n, :songs
end

class Song
    include DataMapper::Resource
    property :id, Serial
    property :title, String
    property :year, Integer
    property :singer, String
    belongs_to :artist
end


DataMapper.finalize


get '/songs' do
    @songs = Song.all
    slim :songs
end

get '/songs/new' do
@song = Song.new
slim :new_song
end

get '/songs/:id' do
@song = Song.get(params[:id])
slim :show_songs
end

post '/songs' do
song = Song.create(params[:song])
redirect to("/songs/#{song.id}")
end

get '/songs/:id/edit' do
@song = Song.get(params[:id])
slim :edit_song
end

put '/songs/:id' do
song = Song.get(params[:id])
song.update(params[:song])
redirect to("/songs/#{song.id}")
end

delete '/songs/:id' do
Song.get(params[:id]).destroy
redirect to('/songs')
end

问题在于，当我尝试为我的空数据库创建一首新歌时，在我提供歌曲的详细信息并按下保存按钮后，我得到404错误。新页面的链接不带/：id延伸，因为它应该。我实际上只更改了DataMapper的类，添加了“DataMapper.auto_upgrade！”并根据新的类属性更改了slim文件。原来是：

configure:development do
    DataMapper.setup(:default, "sqlite3://#{Dir.pwd}/development.db")
end

class Song
    include DataMapper::Resource
    property :id, Serial
    property :title, String
    property :lyrics, Text
    property :length, Integer
    property :released_on, Date

    def released_on=date
        super Date.strptime(date, '%m/%d/%Y')
    end

end

DataMapper.finalize

我怀疑我在DataMapper的类工作方式中遗漏了一些东西。欢迎任何关于我可能做错的想法。

我目前使用的超薄文件是

    #new_song.slim

h1 Add A New Song
form method="POST" action="/songs"
  == slim :song_form


#song_form.slim

label for="title" Title:
input#title type="text" name="song[title]" value="#{@song.title}"
label for="year" Released on:
input#year type="text" name="song[year]" value="#{@song.year}"
label for="singer" Performed by:
input#singer type="text" name="song[singer]" value="#{@song.singer}"
input type="submit" value="Save Song"



/show_songs.slim

h1= @song.title
p Release Date: #{@song.year}
p <a href="/songs">back to songs index</a>
p <a href="/songs/#{@song.id}/edit">edit this song</a>
form action="/songs/#{@song.id}" method="POST"
  input type="hidden" name="_method" value="DELETE"
  input type="submit" value="delete this song"

Answer 1

事实证明这一切都发生了，因为DataMapper希望用户给Artist属性赋值，这也是我在slim文件中没有做的事情。我想这就是id属性保持nil值的原因，我得到404错误。

使用DataMapper在Sinatra App中出现404错误

1 个答案: