Rails: Sprockets::Rails::Helper::AssetNotPrecompiled in development

Question

I am relatively new to Rails and I am trying to use the asset pipeline, SCSS, in the development environment. However, after I created the controller, the view, and the css.scss file, I encounter the following error:

Sprockets::Rails::Helper::AssetNotPrecompiled

Here is the error message:

Asset was not declared to be precompiled in production. Add Rails.application.config.assets.precompile += %w( public.css ) to config/initializers/assets.rb and restart your server

I read that in development, the assets get compiled on the fly and there is no need to pre-compile. Why is there a pre-compile error? Did Rails think that I am in production instead of development?

Edited on 1 March 2016 ------

I just realized that adding files onto the config/initializers/assets.rb works. But is this the right way to do it? I have to add all the css/js/jpg files manually in the assets.rb for it to work. I felt that this somehow violate the DRY principle.

score 146 · Answer 1 · answered Aug 17 '18 at 14:56

146

Neither of these worked for me (rails-5.0.7, sprockets-3.7.2, sprockets-rails-3.2.1):

config.assets.debug = false
config.assets.unknown_asset_fallback = true

But this did:

config.assets.check_precompiled_asset = false

answered Aug 17 '18 at 14:56

eben.english

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literally, ```config.assets.check_precompiled_asset``` worked for me too. rails version 4.2.8 – Alec.Zhou Jun 17 '19 at 15:42
12

Thank you so much, this also worked for me in Rails 6.0.2.1 – yakattack Apr 14 '20 at 08:08
This helped in api only app's issue in Apitome document parsing. – Swapnil Chincholkar Oct 05 '20 at 17:37
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This worked for me in rails 6.0.3.3 when Sprockets couldn't figure out myfile.js.erb was a thing – genkilabs Oct 07 '20 at 00:20
Worked when rails 6 + spina failed out of the box (Oct 2020) – meesern Oct 20 '20 at 06:34
2

Worked for me, but why? App suddenly started throwing these errors for images. Chucking this in development.rb got it working again. – Will Apr 21 '21 at 06:41
only this worked for me Rails 5.2.6 (Oct 2021) – Mayuresh Srivastava Oct 06 '21 at 09:39
1

It works. But doesn't this mean, that it will not verify/check precompiled_assets ? Is it a good thing to do? – Anas Ansari May 11 '22 at 16:06
Thanks. I don't understand that, but Thanks! It worked for me. – jgomo3 Aug 01 '22 at 13:10

score 52 · Answer 2 · edited Dec 16 '21 at 10:53

52

I had the same problem and fixed it by deleting all the cache files inside the tmp folder

rm -rf tmp/cache/assets

edited Dec 16 '21 at 10:53

answered Mar 27 '20 at 10:41

gersanco

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This worked for me, thanks! (rails 5.2.2 / sprockets 4.0.2 / sprockets-rails 3.2.2) – benj-p Feb 18 '21 at 08:43
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Thanks! This is the actual solution.`rm -rf tmp/cache/assets/` – Weston Ganger May 26 '21 at 18:03
Worked for me with Rails 6.1 – Matt Nov 08 '22 at 08:29

score 30 · Answer 3 · edited Sep 02 '22 at 08:10

30

//= link_directory ../javascripts .js

Adding this to app/assets/config/manifest.js
Worked for me (working on rails 6)

edited Sep 02 '22 at 08:10

Jai Chauhan

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answered Oct 05 '20 at 06:07

Ameer Hamza

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I had to add this two lines to make it work `//= link administrate/application.css //= link administrate/application.js` using Rails 6. – alexventuraio Dec 07 '20 at 05:35
Worked for me with rails `6.1.3` – Sathish May 28 '21 at 08:43

score 19 · Answer 4 · answered Sep 27 '20 at 03:07

19

For those who came here after upgrading from rails 4 to 5-6 - checkout manifest.js

app/assets/config/manifest.js

If there is no link to js - just add one:

//= link_directory ../javascripts .js

answered Sep 27 '20 at 03:07

Max Paprikas

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score 9 · Answer 5 · answered Mar 15 '18 at 12:39

9

Changing assets.debug did not work for me in Rails v5.1.5. I had to use this option: config.assets.unknown_asset_fallback = true

answered Mar 15 '18 at 12:39

Arctodus

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score 8 · Accepted Answer · answered Feb 29 '16 at 07:04

8

Please check the file

config/environments/development.rb

config.assets.debug = true (if TRUE change to FALSE)

answered Feb 29 '16 at 07:04

aldrien.h

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config.assets.debug is set to True. – Sydney Feb 29 '16 at 13:58
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try to change it to FALSE – aldrien.h Mar 01 '16 at 01:11
It worked. Thanks. So debug mode does not preprocess the assets, that's why i need to set it off? So the scss files require preprocessing to work? – Sydney Mar 15 '16 at 01:43
Welcome! Yes!, since it will takes time when its required to debug in development environment. But in production mode it is set to true, since you need to precompile all assets for faster rendering and interpreting. – aldrien.h Mar 15 '16 at 01:51
This didn't work for me I am still getting the error, I changed it from true to false – Steven Aguilar Mar 08 '18 at 18:24
Yeah, See Ameer's answer. It worked for me in Rails 5.2.5 https://stackoverflow.com/a/64203218/3300043 – Jamshad Ahmad May 24 '21 at 14:02

score 6 · Answer 7 · answered Aug 27 '19 at 05:38

6

you can initialize this scss file for the following line of code

Rails.application.config.assets.precompile += %w( applicationname.css )

answered Aug 27 '19 at 05:38

muthupandi

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file in which above needs to be changed: config/initializers/assets.rb – Mayuresh Srivastava Dec 28 '20 at 06:55

score 2 · Answer 8 · answered Oct 28 '21 at 06:55

2

I needed to declare my assets in my manifest:

//= link_directory ../stylesheets .css

in app/assets/config/manifest.js

answered Oct 28 '21 at 06:55

Dorian

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bingoding · Answer 9 · 2022-10-17T14:20:58.930

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Try rake tmp:clear

References - https://github.com/rails/sprockets-rails/issues/458

edited Oct 17 '22 at 14:20

answered Oct 17 '22 at 14:19

bingoding

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bingoding is right! ...that's the sound of relief – nimmolo Nov 27 '22 at 08:39

score 1 · Answer 10 · answered Mar 03 '22 at 19:37

Just adding here in case it might help someone.

I had a specific JS files I wanted only in a specific ActiveAdmin page and it was under /app/assets/javascripts/admin/orders.

Initially, none of the solutions worked for me beside adding this to config/environments/development.rb:

config.assets.check_precompiled_asset = false

A coworker mentioned that this change is a bit fishy and I tend to agree. Like what are the implications this will have on our development? Will we see errors related to precompilation of assets only in staging / prod from now?

Since I had subdirectories including JS files under my /app/assets/javascripts folder, I tried changing

//= link_directory ../javascripts .js

to

//= link_tree ../javascripts

And it solved it for me. Without the config.assets.check_precompiled_asset = false in the development.rb file.

score 0 · Answer 11 · edited Sep 02 '22 at 08:10

0

Add this to app/assets/config/manifest.js

//= link_directory ../javascripts .js

edited Sep 02 '22 at 08:10

Jai Chauhan

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answered Sep 28 '21 at 07:38

kushagra gupta

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Your answer could be improved with additional supporting information. Please [edit] to add further details, such as citations or documentation, so that others can confirm that your answer is correct. You can find more information on how to write good answers [in the help center](/help/how-to-answer). – Community Sep 28 '21 at 07:47

score 0 · Answer 12 · answered May 07 '22 at 08:08

0

Do not forget to restart the app too if you pulled new code.

answered May 07 '22 at 08:08

iCyborg

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Rails: Sprockets::Rails::Helper::AssetNotPrecompiled in development

12 Answers12