undefined method `mappings' for Tilt:Module

[lcorsini]

I've installed dashing-icinga2 today, on an ubuntu 16.04 openvz
I've followed install instructions, but when I try to open the dashboard I get this sinatra error page:

NoMethodError at /icinga2
undefined method `mappings' for Tilt:Module
file: dashing.rb location: tilt_html_engines line: 151

Previously I've installed this on a RedHat 7 machine without issues, so I don't know if is an ubuntu issue (and sadly I don't have access to the rh7 machine anymore)

• Dashing version (gem list --local dashing):
  dashing (1.3.2)

• Ruby version (ruby -V):
  ruby 2.3.1p112 (2016-04-26) [x86_64-linux-gnu]

• Version of this project (tarball name, tag name or git show -1):
  commit ccb6e03
  Merge: 14bc597 c800bfd
  Author: Michael Friedrich michael.friedrich@icinga.com
  Date: Fri Oct 6 11:15:28 2017 +0200

  Merge pull request Render Undhandled Problems green if count is zero #45 from Icinga/feature/simplemon-green-if-zero

  Render Undhandled Problems green if count is zero

• Modifications to this project, if any (git diff):

• Operating System and version:
  Ubuntu 16.04
  Linux watcher 2.6.32-042stab117.14 Update README.md #1 SMP Tue Aug 30 17:12:57 MSK 2016 x86_64 x86_64 x86_64 GNU/Linux

• Client browser and version:
  Chrome 61

[urbels]

same for me

[dnsmichi]

Sounds like a Ruby version issue, in relation with Sinatra. Google does not make me happy, maybe the gem install pulls in a "too new" version or something like that.

[urbels]

So you suggest to downgrade ruby version?

[dnsmichi]

To be honest, I think this is a Dashing issue itself, nothing directly related to this dashboard. I don't have the time to reproduce the issue, so I'd suggest looking for possible influences.

As remarked above, RHEL7 uses a different version of Ruby and presumingly gems which are pulled with bundle install.

You can test-drive Dashing inside the icinga-vagrant boxes, there's CentOS 7 inside. Compare the pulled gems and versions with your Ubuntu setup, and dig into possible Google results from this error. Maybe you need to pin a specific gem version, or use a different Ruby version.

[lcorsini]

RHEL7 (or centos, which I've checked now) ships ruby 2.0.0
Ubuntu ships ruby 2.3.1
so maybe there are differences
I'll try to use RVM to see if I can install ruby 2.0.0

[lcorsini]

I've installed RVM and used ruby 1.9.3
Same error
2017-11-13 16:32:34 - NoMethodError - undefined method mappings' for Tilt:Module: /home/lucac81/.rvm/gems/ruby-1.9.3-p551/gems/dashing-1.3.2/lib/dashing.rb:151:in tilt_html_engines'

[dnsmichi]

I'm wondering why you use dashing 1.3.2 ... I've seen dashing 1.3.7 on rubygems.

$ gem search dashing

*** REMOTE GEMS ***

dashing (1.3.7)

According to their release page, 1.3.2 is more than 4 years old.

[dnsmichi]

Hehe, first entry on google.

Shopify/dashing#581 (comment)

[lcorsini]

it gets downloaded from bundler when I run bundle inside dashing directory
if I upgrade and remove it I get this error
./restart-dashing
Could not find dashing-1.3.2 in any of the sources
Run bundle install to install missing gems.

This is what gets installed running bundle
Using backports 3.10.3
Using bundler 1.16.0
Using coffee-script-source 1.12.2
Using execjs 2.7.0
Using coffee-script 2.4.1
Using concurrent-ruby 1.0.5
Using daemons 1.2.5
Using rack 1.6.8
Using thread_safe 0.3.6
Using tzinfo 1.2.4
Using rufus-scheduler 2.0.24
Using sass 3.4.25
Using rack-protection 1.5.3
Using tilt 2.0.8
Using sinatra 1.4.8
Using multi_json 1.12.2
Using rack-test 0.7.0
Using sinatra-contrib 1.4.7
Using sprockets 3.7.1
Using eventmachine 1.2.5
Using thin 1.7.2
Using thor 0.20.0
Using dashing 1.3.2
Using unf_ext 0.0.7.4
Using unf 0.1.4
Using domain_name 0.5.20170404
Using http-cookie 1.0.3
Using json 2.1.0
Using mime-types 2.99.3
Using netrc 0.11.0
Using rest-client 1.8.0

[urbels]

ye bundle installs 1.3.2:
bundle info dashing

• dashing (1.3.2)

Edit: I edited by hand Gemfile.lock to add 1.3.7, then ran bundle update dashing and it updated, but same error.

[dnsmichi]

Hm, so "something" where the dashing gem has a dependency onto, is locking its version where bundle can only install 1.3.2 and not a newer version. Would be interesting to see which other gems you've installed on Ubuntu, preventing an upgrade.

[urbels]

Ah nevermind it doesnt updated because:
Bundler attempted to update dashing but its version regressed from 1.3.7 to 1.3.2

[urbels]

finally fixed.

@lcorsini Delete Gemfile.lock.
Edit Gemfile like this:
gem 'dashing', '1.3.7'

And run bundle and then ./restart-dashing

[dnsmichi]

Interesting, thanks. Let me know whether this should be included upstream in the Gemfile file. Note: Should be tested with CentOS7 inside the Vagrant box too. @bodsch any other thoughts?

[urbels]

As I found in another issue, they suggest to add versions to Gemfile.

[bodsch]

you find it out, no ruby issue. :)
I use an old (2.1) and bleeding edge (2.4) ruby and both are working fine.

1.3.7 is the latest dashing release: https://rubygems.org/gems/dashing and should be work.

i use in my projects smashing (a fork of dashing)

i think, it is better, to define a version into the Gemfile:

gem 'dashing', '~> 1.3'

[dnsmichi]

~> 1.3 won't solve the issue, as this allows for >= 1.3.0 && < 1.4.0. I think we need to explicitly require the latest release from rubygems.org. Other locations won't use the Gemfile anyway. What do you think?

[lcorsini]

Ok with explicit version of dashing in Gemfile it works correctly
Strange that by without explicit version, 1.3.2 gets pulled out.
BTW searching for this problem I found that dashing isn't developed anymore, but there is a replacement called smashing, isn't better to move to that project? or is no big deal at the moment?

[dnsmichi]

As said, I think that bundler evaluates all dependencies and comes to the conclusion that the lowest version satisfies the needs. I don't know all the Ruby internals and package handling, especially not with bundler. Just a guess from that current problem.

The changes in smashing compared to current dashing master are nearly zero, except for tests and docs. The hassle with upgrading and renaming is way too much imho, unless there are real improvements, such as full Windows support.

Btw - dashing is a common name you'll reference with a dashboard. smashing - I would not relate this to a dashboard if I were new. Going the route of leaving the project name intact, but requiring smashing for dashing - I will not take the effort to answer all community questions on that.

TL;DR - I think dashing works quite well in its current form. It definitely is not something one can maintain without some programming knowledge, even if it looks super easy. The entry of creating your own dashboards is super hard. Which is why I wrote development docs.

[bodsch]

i'm absolut conform with @dnsmichi.

it doesn't matter which packet you use.
the develpment of dashing is stopped. since years.
smashing - as fork - too? I dont know.
but both works well.

[dnsmichi]

Found another problem on RHEL7 with dashing -> sinatra -> rack-protection -> rack-test -> Ruby >= 2.2.2 - will fix both.