I have Rails application that will give me number of pages from doc, docx and pdf if I upload it.
To get the number of pages, I use Yomu gem in following way in Document model:
def update_information
doc = Yomu.new(self.doc.url)
self.num_of_pages = doc.metadata['xmpTPg:NPages']
self.file_updated_at = doc.metadata['modified'] || doc.metadata['Creation-Date'] || Time.now
self.file_created_at = doc.metadata['Creation-Date'] || Time.now
end
One of my documents is throwing exception:
*** Psych::SyntaxError Exception: (<unknown>): mapping values are not allowed in this context at line 23 column 15
and I can't figure it out how I could rescue it or avoid the problem without breaking the experience (it's a website).
By googling I tried this:
begin
doc = Yomu.new(self.doc.url)
self.num_of_pages = doc.metadata['xmpTPg:NPages']
self.file_updated_at = doc.metadata['modified'] || doc.metadata['Creation-Date'] || Time.now
self.file_created_at = doc.metadata['Creation-Date'] || Time.now
rescue Psych::SyntaxError, StandardError => e
print e
end
But it didn't work and it's still throwing the error and breaking the flow.
Any suggestion how to fix?
Related
I'm missing something here, but for some reason my begin then rescue Ruby code isn't capturing this error:
#<ActiveResource::ResourceInvalid: Failed. Response code = 422. Response message = Unprocessable Entity.>
This is my code:
begin
ShopifyAPI::CarrierService.create(with some arguments)
rescue StandardError => e
pp e
end
It doesn't ever capture it. In my rescue section I've tried the above but also:
rescue Exception => e
rescue ActiveResource::Errors => e
All with no luck. Where did I go astray?
Thanks
EDIT:
This is the full error, it not really anymore info, but here goes:
#<ShopifyAPI::CarrierService:0x0000000357a0a0
#attributes=
{"name"=>"XXXX",
"callback_url"=>
"https://XX-XX-XX-XX.c9users.io/receive_rate_request",
"format"=>"json",
"service_discovery"=>"true",
"carrier_service_type"=>"api"},
#errors=
#<ActiveResource::Errors:0x00000003578930
#base=#<ShopifyAPI::CarrierService:0x0000000357a0a0 ...>,
#messages={:base=>["you already have XXX set up for this shop"]}>,
#persisted=false,
#prefix_options={},
#remote_errors=
#<ActiveResource::ResourceInvalid: Failed. Response code = 422. Response message = Unprocessable Entity.>,
#validation_context=nil>
That's it!
Because it is not raising an exception, If you want to raise the exception when the response is false, you may have to use create with bang
begin
ShopifyAPI::CarrierService.create!(with some arguments)
rescue StandardError => e
pp e
end
According to the ActiveResource code (lib/active_resource/base.rb):
# <tt>404</tt> is just one of the HTTP error response codes that Active Resource will handle with its own exception. The
# following HTTP response codes will also result in these exceptions:
#
# * 200..399 - Valid response. No exceptions, other than these redirects:
# * 301, 302, 303, 307 - ActiveResource::Redirection
# * 400 - ActiveResource::BadRequest
# * 401 - ActiveResource::UnauthorizedAccess
# * 403 - ActiveResource::ForbiddenAccess
# * 404 - ActiveResource::ResourceNotFound
...
# * 422 - ActiveResource::ResourceInvalid (rescued by save as validation errors)
So it indicates that 422's are rescued by save on validation, which happens when .create is fired, and are bubbled up as validation errors instead.
Looking at lib/active_resource/validations.rb, you can see the ResourceInvalid exception is gobbled:
# Validate a resource and save (POST) it to the remote web service.
# If any local validations fail - the save (POST) will not be attempted.
def save_with_validation(options={})
perform_validation = options[:validate] != false
# clear the remote validations so they don't interfere with the local
# ones. Otherwise we get an endless loop and can never change the
# fields so as to make the resource valid.
#remote_errors = nil
if perform_validation && valid? || !perform_validation
save_without_validation
true
else
false
end
rescue ResourceInvalid => error
# cache the remote errors because every call to <tt>valid?</tt> clears
# all errors. We must keep a copy to add these back after local
# validations.
#remote_errors = error
load_remote_errors(#remote_errors, true)
false
end
So I wonder if it's logging that an exception happened, but is not actually raising an exception because it turns it in to a return false. It does say "local validations" in the comment, but sets remote_errors, so it's not perfectly clear where this code path is executed.
I just created this little currency converter for my Rails 4 app:
module Currency
def self.get_exchange_rate(from_curr = "EUR", to_curr = "USD")
if from_curr == to_curr
result = 1
else
begin
amount = 1
url = "http://www.google.com/finance/converter?a=#{amount}&from=#{from_curr}&to=#{to_curr}"
doc = Nokogiri::HTML(open(url))
result_span = doc.css('span.bld').text
result = result_span.tr('^0-9.', '')
rescue => e
puts e
result = 1
end
end
result
end
end
I haven't done this a lot, so my question would be: How can I deal with the (unlikely) event that Google Currency times out or is not available for some reason?
In that case I would like my result to be 1. How can this be achieved?
Thanks for any suggestions.
You can simply rescue any error that Nokogiri might raise (or OpenURI) like so:
require 'nokogiri'
require 'open-uri'
def currency(a)
Nokogiri::HTML(open(a))
rescue => e
puts e
1 # default value when error is raised
end
puts currency('https://www.somedomainthatdoesntexist.com')
That will print the backtrace of the error and then return the number 1
getaddrinfo: nodename nor servname provided, or not known
1
For a custom timeout actions you can use Timeout module
http://ruby-doc.org/stdlib-2.1.2/libdoc/timeout/rdoc/Timeout.html
It'd be worth looking at this answer to see how to get nokogiri to timeout : Adjusting timeouts for Nokogiri connections
The question makes use of the timeout module which is an option but I think it is better to get the connection to time out as per the accepted answer.
All that will mean that you'll get a Timeout::Error exception raised if the call times out which you then need to handle:
begin
doc = ... use nokogiri ...
result_span = doc.css('span.bld').text
result = result_span.tr('^0-9.', '')
rescue Timeout::Error
result = 1
end
result
Ruby 2.0.0, Rails 4.0.3, Windows 8.1 Update, Roo 1.13.2
I am trying to open an Excel spreadsheet with embedded spaces using Roo. So far, I am unable to do that. I don't really know if this problem is restricted to Roo. If I rename it to eliminate the spaces, I have no problem with it. I tried encoding it, but then it simply said the file doesn't exist. Can I open the file while it contains spaces?
Code sample:
exceptions = [URI::InvalidURIError, IOError]
puts "f is #{f}"
puts "f exist? #{File.exist?(f)}"
begin
xls = Roo::Spreadsheet.open(f)
rescue *exceptions => e
puts e.message
end
encoded_f = URI.encode(f).to_s
puts "encoded_f is #{encoded_f}"
puts "encoded_f exist? #{File.exist?(encoded_f)}"
begin
xls = Roo::Spreadsheet.open(encoded_f)
rescue *exceptions => e
puts e.message
end
gsub_f = f.gsub(" ", "") # Rename file without spaces
File.rename(f, gsub_f)
puts "gsub_f is #{gsub_f}"
puts "gsub_f exist? #{File.exist?(gsub_f)}"
begin
xls = Roo::Spreadsheet.open(gsub_f)
rescue *exceptions => e
puts e.message
end
Output sample:
f is Whitt Report 2014-07-28-0803.xls
f exist? true
bad URI(is not URI?): Whitt Report 2014-07-28-0803.xls
encoded_f is Whitt%20Report%202014-07-28-0803.xls
encoded_f exist? false
file Whitt%20Report%202014-07-28-0803.xls does not exist
gsub_f is WhittReport2014-07-28-0803.xls
gsub_f exist? true
No message is given in the end because the file opens successfully.
This is caused by the way in which the URI module is called in the Roo::Spreadsheet#open method.
I posted a fix to this problem which has now been merged. If you update your Roo gem you should no longer have this issue.
We have an application that makes hundreds of API calls to external services. Sometimes some calls take too much time to respond.
I am using the rake_timeout gem to find time consuming process, so, Timeout::Error will be thrown whenever some request is taking too long to respond. I am rescuing this error and doing a retry on that method:
def new
#make_one_external_service_call = exteral_api_fetch1(params[:id])
#make_second_external_call = exteral_api_fetch1(#make_one_external_service_call)
#Below code will be repeated in every method
tries = 0
rescue Timeout::Error => e
tries += 1
retry if tries <= 3
logger.error e.message
end
This lets the method fully re-run it. This is very verbose and I am repeating it every time.
Is there any way to do this so that, if the Timeout:Error occurrs, it will retry that method automatically three times?
I have a little module for that:
# in lib/retryable.rb
module Retryable
# Options:
# * :tries - Number of tries to perform. Defaults to 1. If you want to retry once you must set tries to 2.
# * :on - The Exception on which a retry will be performed. Defaults to Exception, which retries on any Exception.
# * :log - The log level to log the exception. Defaults to nil.
#
# If you work with something like ActiveRecord#find_or_create_by_foo, remember to put that call in a uncached { } block. That
# forces subsequent finds to hit the database again.
#
# Example
# =======
# retryable(:tries => 2, :on => OpenURI::HTTPError) do
# # your code here
# end
#
def retryable(options = {}, &block)
opts = { :tries => 1, :on => Exception }.merge(options)
retry_exception, retries = opts[:on], opts[:tries]
begin
return yield
rescue retry_exception => e
logger.send(opts[:log], e.message) if opts[:log]
retry if (retries -= 1) > 0
end
yield
end
end
and than in your model:
extend Retryable
def new
retryable(:tries => 3, :on => Timeout::Error, :log =>:error) do
#make_one_external_service_call = exteral_api_fetch1(params[:id])
#make_second_external_call = exteral_api_fetch1(#make_one_external_service_call)
end
...
end
You could do something like this:
module Foo
def self.retryable(options = {})
retry_times = options[:times] || 10
try_exception = options[:on] || Exception
yield if block_given?
rescue *try_exception => e
retry if (retry_times -= 1) > 0
raise e
end
end
Foo.retryable(on: Timeout::Error, times: 5) do
# your code here
end
You can even pass multiple exceptions to "catch":
Foo.retryable(on: [Timeout::Error, StandardError]) do
# your code here
end
I think what you need is the retryable gem.
With the gem, you can write your method like below
def new
retryable :on => Timeout::Error, :times => 3 do
#make_one_external_service_call = exteral_api_fetch1(params[:id])
#make_second_external_call = exteral_api_fetch1(#make_one_external_service_call)
end
end
Please read the documentation for more information on how to use the gem and the other options it provides
you could just write a helper-method for that:
class TimeoutHelper
def call_and_retry(tries=3)
yield
rescue Timeout::Error => e
tries -= 1
retry if tries > 0
Rails.logger.error e.message
end
end
(completely untested) and call it via
TimeoutHelper.call_and_retry { [your code] }
I'm trying to put a file on a site with WEB_DAV. (a ruby gem)
When I follow the example, I get a nil exception
#### GEMS
require 'rubygems'
begin
gem "net_dav"
rescue LoadError
system("gem install net_dav")
Gem.clear_paths
end
require 'net/dav'
uri = URI('https://staging.web.mysite');
user = "dave"
pasw = "correcthorsebatterystaple"
dav = Net::DAV.new(uri, :curl => false)
dav.verify_server = false
dav.credentials(user, pasw)
cargo = ("testing.txt")
File.open(cargo, "rb") { |stream|
dav.put(urI.path +'/'+ cargo, stream, File.size(cargo))
}
when I run this I get
`digest_auth': can't convert nil into String (TypeError)
this relates to line 197 in my nav.rb file.
request_digest << ':' << params['nonce']
So what I'm wondering is what step did I not add?
Is there a reasonable example of the correct use of this gem? Something that does something that works would be sweet :)
SIDE QUESTION: Is this the correct gem to use to do web_DAV? It seems an old unmaintained gem, perhaps there's something used by more to accomplish the task?
Try referencing the hash with a symbol rather than a string, i.e.
request_digest << ':' << params[:nonce]
In a simple test
baz = "baz"
params = {:foo => "bar"}
baz << ':' << params['foo']
results in the same error as you're getting.