PHP developers should know 5 Composer tips _php Tips

Composer is a new generation of PHP-dependent management tools. Its introduction and basic usage can be seen in this new era of Composer PHP dependency management. This article describes the use of composer five tips, I hope to be able to bring your PHP development convenience.

1. Update only a single library

Just want to update a particular library, do not want to update all its dependencies, very simple:

Composer Update Foo/bar 

In addition, this technique can also be used to solve "warning message problems." You must have seen this warning message:

Warning: The lock file is not up to date with the latest changes in composer.json, you may be getting outdated dependencies, run update to update them. 

Rub, what's wrong? Don't Panic! If you edit it composer.json , you should see such a message. For example, if you add or update details, such as library descriptions, authors, more parameters, or even just a single space, you will change the md5sum of the file. Then composer will warn you of the difference between the hash value and the composer.lock record.

So what do we do? updatecommand can update the lock file, but if you add only a few more descriptions, you should not be updating any libraries. In this case, just update nothing :

$ composer Update nothing
Loading composer repositories with package 
information updating dependencies Nothing to install or update 
writing lock file 
generating autoload files 

As a result, composer does not update the library, but updates it composer.lock . Note that nothing is not update a keyword of the command. Just not nothing The result of this package. If you enter foobar , the result is the same.

If you use a composer version that is new enough, you can use the --lock option directly:

Composer Update--lock 

2. composer.json Install the library without editing

You may feel that each installation of a library needs to be changed composer.json too cumbersome, so you can use the require command directly.

Composer require "foo/bar:1.0.0" 

This method can also be used to quickly open a new project. initcommands have --require options that can be written automatically composer.json : (Note that we use -n them so that we don't have to answer questions)

$ composer Init--require=foo/bar:1.0.0-n
$ cat Composer.json
{
  "require": {"
    Foo/bar": "1.0.0"
  }
}

3. Derivation is easy

Did you try to order the initialization create-project ?

Composer Create-project Doctrine/orm Path 2.2.0 

This automatically clones the warehouse and checks out the specified version. This command is handy when cloning a library, and you don't need to search for the original URI.

4. Consider caching, dist package priority

The last year's composer will automatically archive your downloaded dist packages. By default, the dist package is used to add the tag version, for example "symfony/symfony": "v2.1.4" , or a wildcard or version range, "2.1.*" or ">=2.2,<2.3-dev" (if you use it stable as your minimum-stability ).

Dist packages can also be used for branches such as dev-master , GitHub allows you to download a package that a git references. In order to force the use of compression packs instead of cloning the source code, you can use install update the and --prefer-dist options.

Here is an example (I used the --profile option to display the execution time):

$ composer Init--require= "twig/twig:1.*"-N--profile
Memory usage:3.94mb (PEAK:4.08MB), time:0s

$ composer in Stall--profile
Loading composer repositories with package information installing 
 - Installing Twig/twig (v1.12.2)
  downloading:100%

writing lock file 
generating autoload files 
Memory USAGE:10.13MB (PEAK:12.65MB), time:4.71s

$ rm-rf Vendor

$ composer Install--profile Loading composer
R Epositories with package information 
installing dependencies from lock file 
 -Installing Twig/twig (v1.12.2) C16/>loading from cache

generating autoload files 
Memory usage:4.96mb (PEAK:5.57MB), time:0.45s 

Here, twig/twig:1.12.2 the compressed package is saved in the ~/.composer/cache/files/twig/twig/1.12.2.0-v1.12.2.zip . Use directly when reinstalling the package.

5. To modify, the source code first

When you need to modify the library, cloning the source code is more convenient than the download package. You can use --prefer-source to force the selection of the clone source code.

Composer Update Symfony/yaml--prefer-source 

Next you can modify the file:

Composer Status-v you have changes in the following 
dependencies: 
/path/to/app/vendor/symfony/yaml/symfony/ Component/yaml:
  M dumper.php

When you try to update a modified library, composer will remind you to ask if you want to discard the changes:

$ composer Update
Loading composer repositories with package information updating dependencies 
 -updating Symfony/symfony v2.2.0 (v2.2.0-=> v2.2.0) The package has modified
  files:
  M dumper.php
  Discard Changes [Y,n,v,s,?]?

Preparing for the production environment

Finally, when you deploy your code to a production environment, don't forget to optimize for automatic loading:

Composer Dump-autoload--optimize 

The same can be used when installing packages --optimize-autoloader . Without this option, you may find 20% to 25% performance loss.

If you need help, or want to know the details of a particular command, you can read the official document or the Chinese document, or you can view the interactive memo made by Jolicode.

Original address: 5 features to know about Composer PHP
Address: 5 Composer tips that PHP developers should know

Composer is a new generation of PHP-dependent management tools. Its introduction and basic usage can be seen in this new era of Composer PHP dependency management. This article describes the use of composer five tips, I hope to be able to bring your PHP development convenience.

1. Update only a single library

Just want to update a particular library, do not want to update all its dependencies, very simple:

Composer Update Foo/bar 

In addition, this technique can also be used to solve "warning message problems." You must have seen this warning message:

Warning: The lock file is not up to date with the latest changes in composer.json, you may be getting outdated dependencies, run update to update them. 

Rub, what's wrong? Don't Panic! If you edit it composer.json , you should see such a message. For example, if you add or update details, such as library descriptions, authors, more parameters, or even just a single space, you will change the md5sum of the file. Then composer will warn you of the difference between the hash value and the composer.lock record.

So what do we do? updatecommand can update the lock file, but if you add only a few more descriptions, you should not be updating any libraries. In this case, just update nothing :

$ composer Update nothing
Loading composer repositories with package 
information updating dependencies Nothing to install or update 
writing lock file 
generating autoload files 

As a result, composer does not update the library, but updates it composer.lock . Note that nothing is not update a keyword of the command. Just not nothing The result of this package. If you enter foobar , the result is the same.

If you use a composer version that is new enough, you can use the --lock option directly:

Composer Update--lock 

2. composer.json Install the library without editing

You may feel that each installation of a library needs to be changed composer.json too cumbersome, so you can use the require command directly.

Composer require "foo/bar:1.0.0" 

This method can also be used to quickly open a new project. initcommands have --require options that can be written automatically composer.json : (Note that we use -n them so that we don't have to answer questions)

$ composer Init--require=foo/bar:1.0.0-n
$ cat Composer.json
{
  "require": {"
    Foo/bar": "1.0.0"
  }
}

3. Derivation is easy

Did you try to order the initialization create-project ?

Composer Create-project Doctrine/orm Path 2.2.0 

This automatically clones the warehouse and checks out the specified version. This command is handy when cloning a library, and you don't need to search for the original URI.

4. Consider caching, dist package priority

The last year's composer will automatically archive your downloaded dist packages. By default, the dist package is used to add the tag version, for example "symfony/symfony": "v2.1.4" , or a wildcard or version range, "2.1.*" or ">=2.2,<2.3-dev" (if you use it stable as your minimum-stability ).

Dist packages can also be used for branches such as dev-master , GitHub allows you to download a package that a git references. In order to force the use of compression packs instead of cloning the source code, you can use install update the and --prefer-dist options.

Here is an example (I used the --profile option to display the execution time):

$ composer Init--require= "twig/twig:1.*"-N--profile
Memory usage:3.94mb (PEAK:4.08MB), time:0s

$ composer in Stall--profile
Loading composer repositories with package information installing 
 - Installing Twig/twig (v1.12.2)
  downloading:100%

writing lock file 
generating autoload files 
Memory USAGE:10.13MB (PEAK:12.65MB), time:4.71s

$ rm-rf Vendor

$ composer Install--profile Loading composer
R Epositories with package information 
installing dependencies from lock file 
 -Installing Twig/twig (v1.12.2) C15/>loading from cache

generating autoload files 
Memory usage:4.96mb (PEAK:5.57MB), time:0.45s 

Here, twig/twig:1.12.2 the compressed package is saved in the ~/.composer/cache/files/twig/twig/1.12.2.0-v1.12.2.zip . Use directly when reinstalling the package.

5. To modify, the source code first

When you need to modify the library, cloning the source code is more convenient than the download package. You can use --prefer-source to force the selection of the clone source code.

Composer Update Symfony/yaml--prefer-source 

Next you can modify the file:

Composer Status-v you have changes in the following 
dependencies: 
/path/to/app/vendor/symfony/yaml/symfony/ Component/yaml:
  M dumper.php

When you try to update a modified library, composer will remind you to ask if you want to discard the changes:

$ composer Update
Loading composer repositories with package information updating dependencies 
 -updating Symfony/symfony v2.2.0 (v2.2.0-=> v2.2.0) The package has modified
  files:
  M dumper.php
  Discard Changes [Y,n,v,s,?]?

Preparing for the production environment

Finally, when you deploy your code to a production environment, don't forget to optimize for automatic loading:

Composer Dump-autoload--optimize 

The same can be used when installing packages --optimize-autoloader . Without this option, you may find 20% to 25% performance loss.

If you need help, or want to know the details of a particular command, you can read the official document or the Chinese document, or you can view the interactive memo made by Jolicode.

Original address: 5 features to know about Composer PHP
Address: 5 Composer tips that PHP developers should know