Importing .csv file from user and storing data of csv into database using ruby on rails


#1

Hi friends , I am modifying virtualX open source application. I wanted
to
introduce new functionality that is uploading questions from .csv file
and
storing those questions to the database. I am very new to ruby this task
becomes very tough for me . So i referred so many websites and blogs and
i
ready some code for this feature . but this is code is not working . I
am
getting HTTP 500 error . As i checked code in Aptanan Studio , it is
showing some errors. I am posting my code over here . Please help me
friends . I am really not getting what is happening .

I am using Ruby 1.8.7
Rails 3.0.3

questions_controller.rb

def import

@question = Question.new
@question.import(params[:file])
redirect_to root_url, notice: “Questions imported succefully.”
end

questions.rb

def self.import(file)
CSV.foreach(file.path, headers: true) do |row|

question_hash = row.to_hash
@question = Question.where(id: question_hash[“id”])

if @question.count == 1
@question.first.update_attributes(question_hash)
else
Question.save!(question_hash)
end # end if !@question.nil?
end # end CSV.foreach
end # end self.import(file)

question_type_listing.html.erb

<%=t('question.select_qtype_cat')%>
<%= form_tag({:action => "import"}, multipart: true) do %>

<span style="width: 130px; float: left;"><p><label 

for=“upload_file”>
Select File :
<%= file_field_tag :file %>
<%= submit_tag “Import CSV” %>
<% end %>

When i placed this code in respective modules . And restarted server
apart
from this all working fine . Please help me to resolve this issue .

Thanks and regards


#2

On Monday, August 24, 2015 at 9:28:12 AM UTC+1,
removed_email_address@domain.invalid wrote:

Check your log file (development.log) - it should contain extra details
about the problem (such as a stack trace)

I am using Ruby 1.8.7
Rails 3.0.3

Just fyi, both of these 2 release series are unmaintained. Rails 3.0.3 has
several remote code execution flaws

if @question.count == 1
@question.first.update_attributes(question_hash)
else
Question.save!(question_hash)
end # end if !@question.nil?

This line looks fishy - there is no class method called save!. Perhaps
you
meant create! ?

Fred


#3

On Monday, 24 August 2015 04:28:12 UTC-4, removed_email_address@domain.invalid wrote:

Hi friends , I am modifying virtualX open source application. I wanted to
introduce new functionality that is uploading questions from .csv file and
storing those questions to the database. I am very new to ruby this task
becomes very tough for me . So i referred so many websites and blogs and i
ready some code for this feature . but this is code is not working . I am
getting HTTP 500 error . As i checked code in Aptanan Studio , it is
showing some errors.

In future, please also post the errors; since this isn’t all the code in
your application we can’t run it to see what happens, and are relying on
you to tell us.

def import

@question = Question.new
@question.import(params[:file])

You’ve defined the import method below as a class method (def self.import) but are attempting to call an instance method here on
@question.

The two lines above should likely be:

Question.import(params[:file])

Double-check your source file: the line you’ve pasted here has
slant-quotes
(“ and ”) which are not the same thing to Ruby as a straight
double-quote
("). It’s also possible that these were adding while composing the
email.

if @question.count == 1
@question.first.update_attributes(question_hash)
else
Question.save!(question_hash)

What is the intent of this line? Are there situations where you can have
multiple Question records with the same ID? There is not a class
method
called save! built into ActiveRecord.

–Matt J.


#4

def import
@question = Question.new ## You have just created a new instance
of
model class Question
@question.import(params[:file])
redirect_to root_url, notice: “Questions imported succefully.”
end

class Question
validates :id, uniqueness: true ## see below
def self.import(file)
CSV.foreach(file.path, headers: true) do |row| ## okay so you will
iterate by row
question_hash = row.to_hash
## This is okay, but you should put a watch on
row,
and understand its structure. In doing so, you may not need to convert
row
to row.to_hash. Otherwise, you should put a watch on row.to_hash to
verify
that the
## structure of the ‘row’ is consistent with
your
database structure and other matters that may be in your Question model
##@question = Question.where(id:
question_hash[“id”])
## okay this seems reasonable but at the model
level rather than creating a new Question object, you should rather be
doing validation on id, see above.
## If I were you I would do validation on the
record, not just the id
## if @question.count == 1
##@question.first.update_attributes(question_hash) ## self not new
instance of Question
@return_value_on_update_attributes =
self.update_attributes(question_hash) ## Read:
http://apidock.com/rails/ActiveRecord/Base/update_attributes
unless @return_value_on_update_attributes ## unless
@return_value_on_update_attributes is false, eg, if not true
puts "There was an error in record " + question_hash[“id”]
puts self.errors.to_yaml ## This way you can continue, and then
later you need to check for errors. Of course there are other ways to
manage and learn errors. But for now…
end # end unless
end # end foreach

end # end self.import(file)


#5

Correction: obviously class Question < ActiveRecord::Base