I'm trying to deploy an app on Heroku and I'm running into issues related to conflicting composer dependencies. It's working fine from my local dev machine, I can composer update without any issue.
Here is a sample of my composer.json:
"require": {
"php": "7.1.*",
"ext-mongo": "*",
"ext-mongodb": "^1.2",
"symfony/symfony": "3.2.*",
"doctrine/orm": "^2.5",
"doctrine/doctrine-bundle": "^1.6",
"doctrine/doctrine-cache-bundle": "^1.2",
"symfony/swiftmailer-bundle": "^2.3.10",
"symfony/monolog-bundle": "^3.0.2",
"symfony/polyfill-apcu": "^1.0",
"sensio/distribution-bundle": "^5.0",
"sensio/framework-extra-bundle": "^3.0.2",
"incenteev/composer-parameter-handler": "^2.0",
"twig/twig": "^1.0||^2.0",
"mongodb/mongodb": "^1.1",
"doctrine/mongodb-odm-bundle": "^3.2",
"alcaeus/mongo-php-adapter": "^1.0",
"friendsofsymfony/user-bundle": "2.0.0-beta2",
"friendsofsymfony/oauth-server-bundle": "^1.5",
"symfony/assetic-bundle": "^2.8",
"twig/extensions": "^1.4",
"jms/serializer-bundle": "^1.2",
"friendsofsymfony/rest-bundle": "^2.1"
},
...and here is the error output from Heroku:
> Loading repositories with available runtimes and extensions
> Updating dependencies
> Your requirements could not be resolved to an installable set of packages.
>
> Problem 1
> - Installation request for doctrine/annotations v1.4.0 -> satisfiable by doctrine/annotations[v1.4.0].
> - Installation request for twig/twig v2.3.2 -> satisfiable by twig/twig[v2.3.2].
> - Conclusion: don't install php 7.1.3
> - Installation request for doctrine/mongodb 1.4.0 -> satisfiable by doctrine/mongodb[1.4.0].
> - doctrine/annotations v1.4.0 requires php ^5.6 || ^7.0 -> satisfiable by php[5.6.30, 7.0.15, 7.0.16, 7.0.17, 7.1.1, 7.1.2, 7.1.3].
> - don't install php 7.1.1|don't install php 5.5.38
> - don't install php 7.1.2|don't install php 5.5.38
> - don't install php 7.0.15|don't install php 5.5.38
> - don't install php 7.0.16|don't install php 5.5.38
> - don't install php 7.0.17|don't install php 5.5.38
> - ext-mongo 1.6.14 requires php 5.5.* -> satisfiable by php[5.5.38].
> - doctrine/mongodb 1.4.0 requires ext-mongo ^1.5 -> satisfiable by ext-mongo[1.6.14].
> - ext-mongo 1.6.14 requires php 5.6.* -> satisfiable by php[5.6.30].
> - Conclusion: don't install php 5.6.30
This is a bigger problem. Let's divide it into two parts:
Part 1:
Ext-mongo is a legacy driver that does not exist for PHP7.x. But Doctrine-ODM requires ext-mongo. The workaround is to use an adapter that provides an interface for the old driver that uses the new MongoDB driver. There is an explanation in the Doctrine-ODM documentation, but this explanation isn't up-to-date and therefore incomplete/incorrect.
In your case, it means that you remove "ext-mongo" and "ext-mongodb" from the "require" section of your composer file and keep the "alcaeus/mongo-php-adapter" (The adapter will require itself "ext-mongodb" - the new driver.) Unfortunately, this still won't work and brings us to Part 2.
Part 2:
Integrating the alcaeus/mongo-php-adapter as it is currently provided by Packagist will create a composer dependency conflict. There is some discussion about exactly this problem and also if this might be a general composer issue (see here). Also, several solutions are suggested. One solution works for me (I'm also deploying on Heroku):
In the composer.json of the alcaeus/mongo-php-adapter replace:
"provide": {
"ext-mongo": "1.6.14"
},
by:
"replace": {
"ext-mongo": "1.6.14"
},
On GitHub, the master branch of alcaeus/mongo-php-adapter uses the "provide"-version, but there is also a composer-replace branch that uses the "replace"-version. Unfortunately, this branch isn't kept up-to-date.
You can use that "replace" branch as repository for alcaeus/mongo-php-adapter in your composer file:
"repositories": [
{
"type": "vcs",
"url": "https://github.com/alcaeus/mongo-php-adapter"
}
],
"require": {
"alcaeus/mongo-php-adapter": "dev-composer-replace",
...
Alternatively, you could fork the master branch, replace "provide" by "replace" and use that fork as repository.