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Vue on Django, Part 4

Ryan Palo on July 17, 2017

This is Part 4 of my tutorial for making a Vue app powered by a Django REST backend. Finally! We've done it. You've done it. But most importa...

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electrocnic • Jul 22 '18

Thank you a lot for this tutorial series, they help me a lot getting started with web-development from the beginning!

However, I had some problems, which you did not cover (I wonder why you did not have the same problems? I had them on Windows, did not test the tutorial part 4 on Ubuntu yet), especially with the template-part:

First, when I tried to run the server straight forward after doing 1:1 what you did (except that I used axios), there was a blank page and the console said error 404 file .../static/css not found.
I googled for a few hours and eventually managed to figure out that the files config/index.js and format_index_html.py where messing around with the static file paths of the generated index.html.
I also discovered strange artifacts in the final index.html using your format_index_html.py code: I truly believe, that the "' %}" in the css and js lines are messing up the final index.html completely, at least it has a completely broken syntax when I open the index.html in IntelliJ and improve the formatting with "Reformat Code". When I removed the mentioned symbols from the two lines so that the format_index_html.py now looks like the following, I got a valid index.html instead:

import sys
import fileinput

file = 'templates/index.html'

with open(file, "r+") as f:
    s = f.read()
    f.seek(0)
    f.write("{% load staticfiles %}\n" + s)

for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('href=//', "href=\"{% static '"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('css', "css"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('src=//', "src=\"{% static '"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('js', "js"))

Also, I needed to modify the file vuedj/settings.py a bit, so that the statics-part looks like this:

STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'static'),
)

STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')

STATIC_URL = '/static/'

instead of this:

STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'static-vuedj'),
)

STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')

STATIC_URL = '/staticfiles/'

However, I am getting a strange webpack-copy error then:

[copy-webpack-plugin] ERROR in [copy-webpack-plugin] unable to locate 'C:\path\to\my\project\static' at 'C:\path\to\my\project\static'

for which I could not find a solution so far. This prevents the files from proper translation, which results in runtime errors where the browser is complaining that it cannot recognize "import"-statements in javascript.

Do you have any idea how to fix that?
I already tried to read about webpack and the configuration of webpack. I just figured out that the difference between npm run dev and npm run build is, that statics and static file copies are only used at npm run build, which is the reason why I did not get errors during npm run dev.

Ryan Palo • Jul 23 '18

Hmmm... I’m not sure. I wrote this post a good while ago, but I do remember that the vue Django starter repo probably ended up causing more problems than it solved. I’ll take a look at the error you’re talking about and see what I can do.

Thanks for sticking with it and reaching out!

Ryan Palo • Jul 23 '18

From your code snippets, my first guess is that you should probably look at what your Django config’s static_root is set to. See these docs. Specifically the Deployment section. Make sure that’s outputting to the right place. Let me know if this solves it, but otherwise I’ll look deeper as soon as I can.

electrocnic • Jul 23 '18

Thank you for the quick response!! I'll try it out, and I am curious. I played around with these static settings for quite a time already, and am not yet 100% sure what the right settings should be, so this is definitely a good start :)

Ryan Palo • Jul 23 '18

No problem! OK, here's what I've got so far. On a fresh computer (windows, no less!), here were my steps:

I cloned the completed example repo.
I created a python virtual environment: py -3.6 -m venv .venv. You could probably also use python36 -m venv .venv or just python3 -m venv .venv depending on the versions of Python you have.
I installed the JavaScript requirements: npm install
I ran the build: npm run build
Since I'm on windows, I had to manually run each of the steps in deploy.sh manually. First was python format_index_html.py.
As you noticed earlier, format_index_html.py has some issues. I went into /templates/index.html manually and fixed the script tag to have these contents: <script type=text/javascript src="{% static 'app.7ff6b55ccbb5cd067a3d.js' %}"></script>. I think it was just some punctuation tweaks. Your app..js will be slightly different each time.
I installed the Python requirements: pip install -r requirements.txt
I ran collectstatic, which grabs your bundled app and puts it in your static directory: python manage.py collectstatic --noinput
I ran the server: python manage.py runserver

Everything worked like I expected with no import errors.

Some things that might have gone wrong for you:

In my vuedj/settings.py, I've got:

STATICFILES_DIRS = (
    os.path.join(BASE_DIR, 'static'),
)

STATIC_ROOT = os.path.join(BASE_DIR, 'staticfiles')

STATIC_URL = '/staticfiles/'

I notice that the STATIC_URL is different than what you said you're using. Give that a try.

I also don't see the copy-webpack-plugin in my package.json for that repo. Are you using the same versions as me? It wouldn't surprise me if you weren't because my package.json is probably out of date with today's JS standards. Compare with my package.json to be sure.

Ryan Palo • Jul 23 '18

By the way, I've got some ideas in the works for writing a new set of articles that are updated for more modern times: Vue 2, vue-cli, Django 2, etc. I'm not sure when I'll get time to work on them, but I know that these articles and the library versions used here are slowly becoming obsolete.

electrocnic • Jul 23 '18

Really nice, that you tried to reproduce my setup, and that you reply so fast! Appreciate that!

You said, on windows, one has to perform the deploy.sh script manually step by step? Why? I did not do that before, and it seems it does not make any difference for me? I use the git-bash (MINGW64) for windows. I can use shell-scripts like on any other linux system and shell-commands as well.

I also believe that I now, thank your link and your kick into the right direction, understand how the format_index_html.py and Jinja is supposed to work and to look like.

For me, neither the original, nor your version of this script made sense.
npm run build would produce a index.html which already has the links to static files and they look fine. I modified the script so that it adds the Jinja syntax correctly IN MY CASE. I really cannot tell why it is different for me:

import sys
import fileinput

file = 'templates/index.html'

with open(file, "r+") as f:
    s = f.read()
    f.seek(0)
    f.write("{% load staticfiles %}\n" + s)

for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('href=/staticfiles/', "href=\"{% static '"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('.css', ".css' %}\""))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('src=/staticfiles/', "src=\"{% static '"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('.js', ".js' %}\""))

What exactly did I do:
The original index.html template looks like this in my case:

<!DOCTYPE html>
<html>
<head>
  <meta charset=utf-8>
  <meta name=viewport content="width=device-width,initial-scale=1">
  <title>test</title>
  <link href=/staticfiles/css/app.2d31a09d9567f33bfd9cc48d15d26790.css rel=stylesheet>
</head>
<body>
<div id=app></div>
<script type=text/javascript src=/staticfiles/js/manifest.7fd0cdf336adc5dd3e7b.js></script>
<script type=text/javascript src=/staticfiles/js/vendor.cd8054bf01aa59402ea6.js></script>
<script type=text/javascript src=/staticfiles/js/app.a1073c350b2a8c23a52c.js></script>
</body>
</html>

... but now we want to add some {% here %} and some {% there %} to be able to inject the correct static paths dynamically if I understood that right?
Looking at the docs, how the final index.html should look like, I needed to modify the double-slash at href=// to href=/staticfiles/ and as you see I also needed to add "staticfiles" in order to be replaced as a whole by the second parameter, which I could leave as it was in your version. Then I needed to add a "." at the "css" and "js" modifiers, else it would mess up the path like this:

/staticfiles/css/app.2d31a09d9567f33bfd9cc48d15d26790.css

would become:

/staticfiles/css' %} /app.2d31a09d9567f33bfd9cc48d15d26790.css' %}

which was really weird and at the beginning I did not understand where this mess came from.

My fix produces:

{% load staticfiles %}
<!DOCTYPE html>
<html>
<head>
  <meta charset=utf-8>
  <meta name=viewport content="width=device-width,initial-scale=1">
  <title>test</title>
  <link href="{% static 'css/app.2d31a09d9567f33bfd9cc48d15d26790.css' %}" rel=stylesheet>
</head>
<body>
<div id=app></div>
<script type=text/javascript src="{% static 'js/manifest.7fd0cdf336adc5dd3e7b.js' %}"></script>
<script type=text/javascript src="{% static 'js/vendor.cd8054bf01aa59402ea6.js' %}"></script>
<script type=text/javascript src="{% static 'js/app.a1073c350b2a8c23a52c.js' %}"></script>
</body>
</html>

...which you probably also had in your case? Else I would not be able to understand how your app would have ever worked?

I also adapted my static files to what you said, indeed a minute before I read your reply :D
It makes sense and looks correct.

However, now I am getting the 404 not found at just one file, others are correctly loaded. I did not get the weird webpack error anymore, but the page is not visible anymore :D

This guy has the same problem and eventually found a solution for himself, I will try that approach tomorrow:
stackoverflow.com/questions/308575...

Really thank you so much for your fast replies, they really helped a lot, and I am indeed interested in Vue 2, vue-cli tutorials as well :D

Ryan Palo • Jul 23 '18

I'm glad that you're headed in the right direction. Let me know if you have any other questions! :)

electrocnic • Jul 26 '18

FUCK

Sorry, but I just wrote 30minutes of well-formatted documentation for my 3 bugfixes, which was deleted as I accidentely clicked "reload" on this page :(

Now I want at least share a short docu for my main 3 bugs, which I was able to solve, for anybody who comes after me and might have the same struggles:

1st: I installed the newest vue-cli:

npm uninstall vue-cli -g
npm install -g @vue/cli

Source: cli.vuejs.org/guide/installation.html

2nd: I fixed the format_index_html.py like described in the comment above, but here is the full file again:

import sys
import fileinput

file = 'templates/index.html'

with open(file, "r+") as f:
    s = f.read()
    f.seek(0)
    f.write("{% load staticfiles %}\n" + s)

for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('href=/static/', "href=\"{% static '"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('.css', ".css' %}\""))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('src=/static/', "src=\"{% static '"))
for i, line in enumerate(fileinput.input(file, inplace=1)):
    sys.stdout.write(line.replace('.js', ".js' %}\""))

Will fix the broken index.html template and thus will also fix half of the issues with static files, to be correctly served at runtime.

3rd: Fixed the CopyWebpackPlugin error ERROR in [copy-webpack-plugin] unable to locate '[...]/static' at '[...]/static':
Therefore, a workaround in the build/build.js was necessary. All it does is adding a .gitkeep to the STATIC_ROOT directory before the build.

...

//add these lines to the other imports:
const webpackConfig = require('./webpack.prod.conf')
const mkdirp = require('mkdirp')
const fs = require("fs")

...

// add the mkdirp function in the rm-callback:
rm(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
  if (err) throw err
  mkdirp(path.join(config.build.assetsRoot, config.build.assetsSubDirectory), err => {
    if (err) throw err
    // path exists unless there was an error
    fs.closeSync(fs.openSync(path.join(config.build.assetsRoot, config.build.assetsSubDirectory, '.gitkeep'), 'w'));
  });

  webpack(webpackConfig, function (err, stats) {
    spinner.stop()

    ...

Source: github.com/dvallin/agora/issues/1

4th: I had the following bug at runtime, when I tried to add TODO-Entries:
TypeError: Cannot read property 'push' of undefined

and fixed it by modifying the response.body to response.data in the store/index.js (I renamed that file from store.js to index.js):

...

'GET_TODOS': function (state, response) {
  state.todos = response.data
},
'ADD_TODO': function (state, response) {
  state.todos.push(response.data)
},

...

Hopefully this helps other people who might have the same struggles.

Thanks again for the nice tutorial, maybe I will see other tutorials by you, Sir! :)

Ryan Palo • Jul 26 '18

Nicely done! I’m sure a lot of people will appreciate this.

Don • May 12 '18

Ryan,
Very nice tutorial and very useful. I'm in the throes of "duplicating" what you did to build my own toolchain (Python/Django/Vue/PyCharm/Anaconda and a few other things) and it's a bit of a beast.

The only thing I may have missed was the creation of a "production" instance of the front end to run without using 'npm run dev' and a corresponding 'manage.py collectstatic' or am I missing something. Maybe that's all hidden under the '/deploy' [I'm on Win10 :-( ]?

Total aside: I'm a retired geek trying to stay somewhat current. Best of luck with your teaching goal. We need good teachers!
--Don

Ryan Palo • May 12 '18

Hi! Thanks so much for reading, I’m glad it’s helping. There have been a lot of changes in the ecosystem since I wrote this, and I should probably go back and refresh it for new versions of the libraries (Django 2.0!). In theory, for production, you should build your JavaScript app into a bundle to be served as static files by your Django server. Does that help? Let me know if you need more guidance and I’ll see if I can write something more specific up. 😃 this stuff is hard, so don’t worry!

Don • May 21 '18

Ryan,
Just a bit of a follow-up. I've gone down the Vue rat hole pretty deeply and am in the throes of some pretty hard (at least for me) problems. Don't know if it is something you might want to develop a tutorial on, but I thought I'd give you the idea.

The first issue I ran into was the decision about the structure of my Vue/Vuex app. Do I start with the small and simple and attempt to grow/refactor as my problem grows or do I build a full blown component/module structure as a frame and fill it in. I chose the latter (in retrospect, maybe wrongly) on the theory that once I had the frame, it would be more straightforward to build everything else and I'd avoid a lot of rework later on.

After some false starts, I decided to set up the vuex.js examples (github.com/vuejs/vuex) and model mine on the shopping cart version. The approach worked well as I could do side-by-side editing and adapting.

The issue I've run into and the place where I think a tutorial would be very useful is in understanding the various ways to reference/call from module/component to another module/component. Specifically, most of the existing examples are pretty good about references using the operations within the html, but I've really struggled to be able to reference actions in one module from methods in another, from pure js (not in an action/method/data/...) in one module to elements in another. The issue seems to revolve around how Vue/Vuex and webpack set things up, but I've really about broken my pick trying to connect things.

Anyway, I may have fallen in my own traps, but I thought it might be a place where you could do a useful tutorial if you are so inclined.

Good luck,
--Don

Ryan Palo • May 21 '18

OK, that's some great insight. I'll be sure to try to get that figured out and worked in. Thanks for grinding through all of the tough stuff! I hope it starts to get easier!

Don • May 21 '18

I just discovered that 'mixins' apparently implement the functionality I've been struggling to create. Might be useful when you do your update.

Steve Mayne • Nov 8 '17

Thanks for taking the time to write this tutorial Ryan; hugely appreciated!

Ryan Palo • Nov 8 '17

I’m glad you liked it. I think there’s still a lot of room for improvement as I keep learning Vue, but it’s hopefully a good jumping off point 😬

Steve Mayne • Nov 8 '17

There is doubtless much that can be improved, but you've moved me on from "I must learn some front-end framework! I've been meaning to start for a couple of years..."

So thank you, from a traditionally back-end developer who doesn't get to play with user interfaces very much!

By the way, your writing style is superb. I wish you every success in your quest to learn everything :-)

Ryan Palo • Nov 8 '17

Oh man that’s so nice, thanks! I’m glad I could help out. Good luck!

ｉｏ • Mar 5 '19 • Edited

Thank you very much for the tutorial!
Do you have any idea on how I could implement Vue 2 in my already existing Django blog?
It is not very clear to me how to handle content rendering. Am I using Django templates? Do I include my Vue components in my templates?
It's all blurry :-))

Ryan Palo • Mar 5 '19

No problem. There are a couple ways to go. If you want Vue to handle the whole thing, then you can basically write the whole template in vue and just have Django serve a barebones template that just serves the vue JavaScript. If you just want vue to handle a smaller piece of the page that needs to be more responsive/interactive, then you can do the majority of the template in Django and source the js for the vue template where you need it. Don’t forget that at the end of the day, vue is just JavaScript, so you can treat it like any other vanilla JavaScript you are adding to your site. Does that help at all?

ｉｏ • Mar 5 '19

Hmmm, not sure I fully see it now, I need to tinker with it a bit. Thank you for replying!

Ryan Palo • Mar 5 '19

One thing that helped me was when I realized that I could simply include Vue as a script tag and have some of my templating logic live right on the same HTML file as my page layout. Here's another good resource that has a nice ramp-in. Hopefully that helps. Let me know what other questions you have, and hopefully I can help :)

ｉｏ • Mar 5 '19

Okey dokey, will check it out. i am onto something. Will tell you how it goes when I have something ready-ish

Ryan Palo • Mar 5 '19

Definitely do. I'm excited to see how it turns out!

annapamma • Nov 9 '17

Okay, I just finished the whole tutorial, and I wanted to say thank you again!! I signed up for dev.to just to thank you! I also wanted to let you know that I work for a cancer research lab at a large institution, and your post is helping me build a web app to assist biologists with their research. So once again, thanks! :)

Ryan Palo • Nov 9 '17

Oh my gosh! That's so amazing! Well, let me know if there's any way I can help. Also, let me know if you figure out a better way to do things. I wrote this as I was first learning Vue, so I'm sure there are ways to improve. Or even better, share a blog post with your brand new Dev.to account! :)

VidJa • Nov 26 '17

Thanks too. I'm also using your vue tutorial in a scientific context. I want to revamp my old django site on microbial genomes to a vue.js app.

b.t.w. I found the following post helpful in preventing cors errors during debugging.
stackoverflow.com/questions/357609...

I'm looking forward to see an update using axios

electrocnic • Jul 24 '18

If you wonder why it does not work on windows to run the deploy.sh:

Use the git-bash for windows
Insert this line as the very first line into the deploy.sh:

#!/bin/sh

chmod 755 deploy.sh and you should be able to run it in the git bash with
./deploy.sh

Ryan Palo • Jul 24 '18

Thanks for the tip! I do know why it doesn't work, I just don't like to use git-bash on this particular machine. I really actually like using PowerShell :)

Willie Zheng • Nov 21 '17

It is pleasant to read your blog. But I was suggested to use axios instead of vue-resource.

Ryan Palo • Nov 21 '17

Thanks! You are correct. I just looked and vue-resource has been depreciated. I'll update the article. Thanks!