update to 8.4 with composer

What output did you get from Composer?

I tried the same thing and it failed because I was on PHP 7.0.0 and the Symfony update failed because it needs 7.0.8 or higher.

With Drupal 8, minor version upgrades have become a major headache. So easy to get caught in dependency hell. The Windows Vista of Drupal releases...

It's all kind of aggravating. If I run
composer outdated
It says that 8.3.7 is outdated and should be updated to 8.4.0

But if I run
composer update --with-dependencies drupal/core
it says "Nothing to install"

If I update the composer.json file so that it specifies 8.4
"drupal/core": "~8.4",
that doesn't work because 8.3.7 specifies
"symfony/class-loader": "~2.8",
Which conflicts with the requirements in 8.4, so the whole thing fails.

Problem 1
    - Conclusion: don't install drupal/core 8.4.0
    - Conclusion: don't install drupal/core 8.4.0-rc2
    - Conclusion: don't install drupal/core 8.4.0-rc1
    - Conclusion: don't install drupal/core 8.4.0-beta1
    - Conclusion: don't install drupal/core 8.4.0-alpha1
    - Conclusion: don't install drupal/core 8.5.x-dev
    - Conclusion: remove symfony/class-loader v2.8.28
    - Installation request for drupal/core ~8.4 -> satisfiable by drupal/core[8.4.0, 8.4.0-alpha1, 8.4.0-beta1, 8.4.0-rc1, 8.4.0-rc2, 8.4.x-dev, 8.5.x-dev].
    - Conclusion: don't install symfony/class-loader v2.8.28
    - drupal/core 8.4.x-dev requires symfony/class-loader ~3.2.8 -> satisfiable by symfony/class-loader[3.2.x-dev, v3.2.10, v3.2.11, v3.2.12, v3.2.13, v3.2.8, v3.2.9].
    - Can only install one of: symfony/class-loader[3.2.x-dev, v2.8.28].
    - Can only install one of: symfony/class-loader[v3.2.10, v2.8.28].
    - Can only install one of: symfony/class-loader[v3.2.11, v2.8.28].
    - Can only install one of: symfony/class-loader[v3.2.12, v2.8.28].
    - Can only install one of: symfony/class-loader[v3.2.13, v2.8.28].
    - Can only install one of: symfony/class-loader[v3.2.8, v2.8.28].
    - Can only install one of: symfony/class-loader[v3.2.9, v2.8.28].
    - Installation request for symfony/class-loader (locked at v2.8.28) -> satisfiable by symfony/class-loader[v2.8.28].

Installation failed, reverting ./composer.json to its original content.

So as I mentioned above, you're stuck in dependency hell. You can't update to 8.4 because Symfony 2.8.28 is incompatible with 8.4. You can't update to Symfony 3.2 because it's incompatible with 8.3.7.

Aggravating. After many attempts with many different combinations, I have no idea how to update Drupal to 8.4

It seems that this is a pretty common problem and most people find that to update Drupal they need to
- delete /vendor
- delete composer.lock

See
https://www.drupal.org/node/2914193
https://www.drupal.org/node/2913970
https://www.drupal.org/node/2879621
https://drupal.stackexchange.com/questions/234321/updating-core-from-8-2...

That did not work for me, so I tried deleting the /web/core directory as well and then running composer.

No luck. No matter what I do, I'm stuck in dependency hell.

This is awful. I can't imagine doing this every few months with each minor upgrade. After using Drupal since 4.5, I think Drupal 7 may be my last version. This is my third effort with Drupal 8 and every experience has been terrible.

Finally sorted this out. What a PITA.

The Drupal 8.4 release notes say that you need to upgrade to Drush 8.1.14, but when I ran composer update, it was choking because Drush 8.1.14 is incompatible with Drupal 8.4

If you look at the Drush docs, it says there that the 8.x branch is only for Drupal 8.3- and Drush 9.x is for Drupal 8.3+

So same dependency problem. There's also the Symfony dependency problem as well, where you need ~3.2.8, but you're locked at 2.7 by the Drupal 8.3 composer.json file.

I had previously deleted /vendor and /web/core from my project. I'm not sure that's necessary.

I finally just explicitly specified the versions I needed in my update commmand

composer update --with-dependencies drupal/core:~8.4 symfony/class-loader:~3.2.13 drush/drush:~9.@dev

If you have the default minimum-stability=stable, you need the @dev for drush even though in theory the tilde operator should handle that. I'm not sure why, but I needed the @dev despite the tilde operator

That finally got me upgraded to Drupal 8.4

It also destroyed my Drush install. So then I did another install of Drush and it sort of worked, but it gave warnings because all the cache commands were missing and for some reason it will not recreate them. So I had lots of error messages likes

[warning] file_put_contents(C:/Users/Tom/.drush/cache/factory/Drush\Drupal\Commands\core\DrupalCommands.cache): failed to open stream: No such file or directory JSONCache.php:25

As you can see, this is on a Windows dev box and Drush had never worked great with Windows, so that is probably the issue here.

I fixed this by simply going into /vendor/drush/drush/src and copying
./Drupal/Commands
./Commands

to the

~/.drush/cache/factory/Drush

directory and using Bulk Rename Utility to rename all .php files to .cache

Now everything works... but of course the second your clear your cache, all the cache files are missing again and for some reason Drush is not generating them.

Clearly this is not a process I want to repeat. There has to be a better way. I'm starting to think the easiest way around this is just to switch to Backdrop!

I had the same problem.
Running composer require drush/drush:^9 before running composer update worked for me.

See this Github thread for Drush

https://github.com/drush-ops/drush/issues/3033

May be: https://www.drupal.org/node/2913970#comment-12292929

1.
edit composer.json
change drupal version to ^8.4
if any change drush version ~9.0

2.
rename /vendor to /_vendor
rename /core to /_core
rename composer.lock to _composer.lock
- - available for easy rollback if problems occur

3.
run composer update drupal/core

4.
from browser run {site}/update.php

5. clear the cache from either admin GUI or drush

6. check basics from admin GUI, such as status report

7.
delete /_vendor
delete /_core
delete _composer.lock

8. proceed to Drupal 8.4.0 - test carefully
- this update causes various known problems, such as breaking existing site features that use jquery

This is what worked for me

Requirement : PHP 7.1
Explanation :
1. Doctrire, a dependancy of Drupal core, requires PHP 7.1. Doctrine uses the latest PHP 7.1 syntax to declare the methods' return type eg. function my_function() : void {...}
2. webflo breaks the chain of dependencies
3. Drupal 8.4 requires Drush 9.0

If you have PHP 7.1 on your server you can do the following:
1. edit the composer.json file

	"drupal/core": "~8.4"
	"drush/drush": "~9.0"

2. delete composer.lock
3. update webflo
composer require "webflo/drupal-finder ~1.0.0"
4. update the database
../vendor/bin/drush updb -y
5. update the entities schemas
../vendor/bin/drush entup -y
6. clear the cache
../vendor/bin/drush cr

...then skip composer and use drush from the web root.

drush up

Worked like a charm for me when upgrading from 8.3.7 to 8.4.0.  

This worked nicely for me; you might want to skip the phpunit there if your project doesn't have it. 

composer require drupal/core:^8.4.0 drush/drush:^8.1.15 phpunit/phpunit:^4.8 drupal/console:^1.0 --update-with-dependencies

As "steps - d 8.4.0 update with composer" above, but a few gotchas I had to research:

"require": {
        "drupal/core": "^8.4.0",
        "drush/drush": "~9.0"

Remove:     "replace": {
        "drupal/core": "~8.3"
    },

Also when adding modules I found duplications outside of the contrib folder that I removed and then composer required again to the latest version, this placed them in contrib folder.

Drush updb then drush cr

More detailed options here: https://www.drupal.org/docs/8/update but apparently once you use composer on a site you have to stick with it for updating core.

I am testing out a Composer based work-flow, and just updated a vanilla Drupal with these steps:

# download Drupal 8.4.0
$ composer create-project drupal-composer/drupal-project:8.x-dev my_web_site --stability dev

# update to Drupal 8.4.4 and Drush 9.0.0-rc2
$ cd my_web_site 
$ composer require "drupal/core:~8.4.4" "drush/drush:~9.0"

# it will update these two lines in composer.json, as well as update some packages:
"drupal/core": "~8.4.4",
"drush/drush": "~9.0",

# finish the update, apparently some extra packages needs updating
$ composer update --with-dependencies

Result:

$ vendor/drush/drush/drush st
Drupal version : 8.4.4
Drush version  : 9.0.0-rc2

EDIT: I know this isn't an update from 8.3.x, but I ended up here searching for a way to get the latest Drupal 8.4.4 version via Composer.

Updating Drupal should not be like this.

I was only able to update to 8.5.0 by manually changing the composer file:

"drupal/core": "^8.5"

Things I understand and do not understand about update core with composer:

1. Always delete composer.lock file.  This I understand.

2. Sometimes delete the vendor folder is needed.  I do not understand the “when/why" of when I need to do this.

3. Core does not update unless “drupal/core” is in the “require” section of  composer.json not the “replace” section:

"require”: {
"drupal/core": "^8.4"
},

not

"replace": {
"drupal/core": "^8.4"
},

So, why does Drupal ship with it in the replace section?

So, am I supposed to change that? Here I am told to completely migrate to https://github.com/drupal-composer/drupal-project, what ever that means, and why I would be better is out of scope of my retarded mind. So please can somebody of the almighty Drupal gods help us here!

I wrote a how-to to solve troublesome drupal updates. This works to get to 8.5.1 (latest version currently)

If anything doesn't work or you think there should be changes to this let me know and i'll change it. I think something like this needs to be on the official guide:

https://am-digital.tumblr.com/post/172489444983/updating-drupal-8-core-a...

Even though it's getting old, some very valid things have been mentioned in this thread. Though we are using a fully Composer-based workflow now successfully with a lot of Drupal websites, I think the whole experience for newcomers could and should be better.

1) I also don't understand why Drupal is shipped with drupal/core in the replace section when updating only works when it's in the require section. I've written a script to automatically patch the composer.json but I think it's ridiculous.

2) Next, I don't understand why drupal create-project is advocated everywhere as if it was free beer, even though I see hardly any need for it and it causes some disturbing complexities (e.g. that you have an additional folder level you don't want etc.).

IMHO: The "plain" method without any create-project stuff is by far the easiest for newcomers. And as an added benefit you can easily transition existing websites to this method. At least it should be mentioned *somewhere*. Back then when I wanted to transition to Composer I found this as my first search result:

https://www.drupal.org/docs/develop/using-composer/using-composer-to-man...

Option A, B and C are all equally confusing and the very easy method of just moving drupal/core from replace to require isnt even mentioned there.

With the new composer version 1.7.3, it's unfortunately also necessary to modify core/composer.json in addition to composer.json. Otherwise you'll end up with lots of conflicts. Took me a while to figure this out. In core/composer.json, you'll also need to merge all the stuff in replace into the require section while changing "self.version" to "@dev". Crazy. Until the Drupal team finally has mercy some day and delivers a decent setup out-of-the-box which doesnt need rocket science to update with composer, I've created a script to get back my sanity. Perhaps this also useful for someone else. I dont know whether it will work for everyone - make sure you do a backup before. Pull requests highly welcome.

https://github.com/rgpublic/drupal_composer_fix

You can just call the script from your Drupal root folder and it will automatically detect which changes are necessary and it fixes everything so you can update properly. Since updates of Drupal core will overwrite core/composer.json, make sure you run the script after any core update.