Monthly Archives: May 2016

To commit composer.lock or not

Whether to commit a composer.lock-file to a repository or not seems to be a somewhat religious decision. Either you follow Raphael Dohms and commit your lock-file or you follow Marco Pivetta and you don’t.

But I think the truth is somewhat in between.

Recently I decided to create a badge for Badge Poser that shows whether the lock-file is commited or not. It’s something you can see easily from the repo but hey, it’s a fun project!

And instantly I stumbled over a commited lock-file! Because as it seems, commited composer.lock-files can be a blessing or a curse. What happened? I thought – as the project commited their composer.lock-file – it would be a good idea to run a composer install instead of a composer update. After all I should be left with a working installation after the install-command. That’s why we would commit the lock-file in the first place, isn’t it?

But as it turned out, the composer.lock-file was created some time ago with a now hopelessly outdated PHP-version. I have PHP 7 running on my machine, but the composer.lock-file obviously was created using something like PHP 5.3 or PHP 5.4. So instead of getting a running version of the project, I got composer yelling at me that it can’t resolve an installable version of my lock file. Hm.

Version mismatch

So it looks like it’s dependent on the PHP-Version you are running whether the composer.lock can be used or has to be updated. Sadly there’s no hint that tells me which PHP-Version the file has been created with so I will have to test whether an install will work or not.

Entry the “config/platform”-parameter. It allows the creator of a package to specify what PHP-Version should be used to resolve the dependencies regardless of what the actual PHP-Version is. This might have the consequence of installing useless packages as installed packages might not work on the installed PHP-Version.

So one thing to have in mind when committing or receiving a composer.lock-file is, that it contains a set of dependencies, that was working for the committer but it might not work for the user as the environment might have changed to a point where the packages of the composer.lock-file might not be usable anymore. Consider a locked Version of phpunit/phpunit:4.8 because the file was created using PHP 5.5 and you are running PHP 7.

Dev-Mismatch

The second thing that came to my mind was that the lock-file might or might not contain the dev-requirements. So when you are developing a lib you’d want other developers to have the same versions of your dev-tools so it’s a good idea to have them in the lock file. And when you are developing a web-project (website of a certain extend) you might want to use the lock-file to automatically deploy the libs you where testing agains. But as it’s for deployment you’d create the lock-file without the dev-dependencies. That will then leave other developers without the dev-dependencies, so they will have to run a composer update (because composer install will tell you that you should either run composer install --no-dev or composer update) anyway.

And also when you do automated testing against the lowest,locked,latest-strategy you might run into issues with locked packages not being able to run on the current platform even though they are installed without an issue. Have a look for example at https://travis-ci.org/heiglandreas/composerlocktest/jobs/133745846. The test fails due to PHPUnit being installed in the wrong version due to that version being locked in the composer.lock-file

Conclusion

Be careful when you commit your lock-file. Indicate clearly what PHP-Version you used when creating it. Either by providing the suggested version using the platform-Parameter or by pointing it out in the documentation very clear. And remember to only automatically test the locked dependencies with the PHP-Versions you created the composer.lock

Be careful when you use a lock-file. Check whether there is a hint to the provided version in the composer.json file or in the documentation of the project you are using. Have a look at the CI-config-file, it might give you a hint.

Timezones and PostgreSQL

After the aforementioned talk (and in preparation to the next installment of it) I checked how to do the MySQL-Example in PostgreSQL. It’s easily possible, but it takes a bit more time to get around to it. But hey, it’s a tool for grown-ups, isn’t it? 😉

Again we create the table using this snippet:

CREATE TABLE datetime(
  zeit timestamp without time zone,
  zone character varying(255)
)

INSERT INTO datetime (zeit, zone)
VALUES
    ('2014-03-04 12:23:34','Europe/Berlin'),
    ('2016-05-03 23:12:23','Europe/Busingen'),
    ('2016-05-03 23:12:23','America/Chicago')
;

So to select all entries that are before 14:00H in UTC-Timezone in PostgreSQL we’ll use this query:

SELECT * FROM datetime 
WHERE 
    extract(HOUR FROM zeit AT TIME ZONE zone AT TIME ZONE 'UTC')
    <= 14;

Here we tell PostgreSQL to interpret the value in zeit as localtime in timezone zone and then to convert that to timezone UTC. It will output this:

2014-03-04 12:23:34 | Europe/Berlin
2016-05-03 23:12:23 | America/Chicago