Allow bypassing curl package ensure if needed

Author: esalberg

README.md

@@ -235,6 +235,14 @@ class { 'docker':
 }
 ```
 
+If the curl package is being managed elsewhere and the curl ensure in this module is conflicting,
+ it can be disabled by setting the following parameter globally or in compose / machine resources:
+```puppet
+class { 'docker':
+  curl_ensure => false
+}
+```
+
 ### Proxy on Windows
 
 To use docker through a proxy on Windows, a System Environment Variable HTTP_PROXY/HTTPS_PROXY must be set. See [Docker Engine on Windows](https://docs.microsoft.com/en-us/virtualization/windowscontainers/manage-docker/configure-docker-daemon#proxy-configuration)

manifests/compose.pp

@@ -37,14 +37,19 @@
 #   responsible for ensuring the URL points to the correct version and
 #   architecture.
 
+# [*curl_ensure*]
+#   Whether or not the curl package is ensured by this module.
+#   Defaults to true
+#
 class docker::compose(
   Optional[Pattern[/^present$|^absent$/]] $ensure          = 'present',
   Optional[String] $version                                = $docker::params::compose_version,
   Optional[String] $install_path                           = $docker::params::compose_install_path,
   Optional[String] $symlink_name                           = $docker::params::compose_symlink_name,
   Optional[String] $proxy                                  = undef,
   Optional[String] $base_url                               = $docker::params::compose_base_url,
-  Optional[String] $raw_url                                = undef
+  Optional[String] $raw_url                                = undef,
+  Optional[Boolean] $curl_ensure                           = $docker::params::curl_ensure,
 ) inherits docker::params {
 
   if $proxy != undef {
@@ -93,7 +98,9 @@
         require => Exec["Install Docker Compose ${version}"]
       }
     } else {
-      ensure_packages(['curl'])
+      if $curl_ensure {
+        ensure_packages(['curl'])
+      }
       exec { "Install Docker Compose ${version}":
         path    => '/usr/bin/',
         cwd     => '/tmp',

manifests/machine.pp

@@ -23,12 +23,17 @@
 # [*url*]
 #   The URL from which the docker machine binary should be fetched
 #   Defaults to a auto determined value based on version, kernel and OS.
+# 
+# [*curl_ensure*]
+#   Whether or not the curl package is ensured by this module.
+#   Defaults to true
 class docker::machine(
   Optional[Pattern[/^present$|^absent$/]]              $ensure       = 'present',
   Optional[String]                                     $version      = $docker::params::machine_version,
   Optional[String]                                     $install_path = $docker::params::machine_install_path,
   Optional[String]                                     $proxy        = undef,
   Optional[Variant[Stdlib::HTTPUrl, Stdlib::HTTPSUrl]] $url          = undef,
+  Optional[Boolean]                                    $curl_ensure  = $docker::params::curl_ensure,
 ) inherits docker::params {
 
   if $proxy != undef {
@@ -75,7 +80,9 @@
         require => Exec["Install Docker Machine ${version}"]
       }
     } else {
-      ensure_packages(['curl'])
+      if $curl_ensure {
+        ensure_packages(['curl'])
+      }
       exec { "Install Docker Machine ${version}":
         path    => '/usr/bin/',
         cwd     => '/tmp',

manifests/params.pp

@@ -109,6 +109,7 @@
   $storage_pool_autoextend_percent   = undef
   $storage_config_template           = 'docker/etc/sysconfig/docker-storage.erb'
   $registry_mirror                   = undef
+  $curl_ensure                       = true
   $os_lc                             = downcase($::operatingsystem)
   $docker_msft_provider_version      = undef
   $nuget_package_provider_version    = undef