providers/docker: set preparing set to avoid data dir clear [GH-3873]

CHANGELOG.md

@@ -12,6 +12,7 @@ BUG FIXES:
   - core: Fix cases where sometimes SSH connection would hang.
   - commands/box: `--cert` flag works properly. [GH-4691]
   - command/docker-logs: Won't crash if container is removed. [GH-3990]
+  - command/docker-run: Synced folders will be attached properly. [GH-3873]
   - command/rsync: Sync to Docker containers properly. [GH-4066]
   - providers/docker: Create args works. [GH-4526]
   - providers/docker: Nicer error if package is called. [GH-4595]

plugins/providers/docker/action.rb

@@ -215,7 +215,7 @@ module VagrantPlugins
       def self.action_start
         Vagrant::Action::Builder.new.tap do |b|
           b.use Call, IsState, :running do |env, b2|
-            # If the container is running and we're doing a run, we're done
+            # If the container is running and we're not doing a run, we're done
             next if env[:result] && env[:machine_action] != :run_command
 
             if env[:machine_action] != :run_command
@@ -231,7 +231,10 @@ module VagrantPlugins
             end
 
             b2.use Call, IsState, :not_created do |env2, b3|
-              if !env2[:result]
+              if env2[:result]
+                # First time making this thing, set to the "preparing" state
+                b3.use InitState
+              else
                 b3.use EnvSet, host_machine_sync_folders: false
               end
             end
@@ -247,7 +250,7 @@ module VagrantPlugins
             if env[:machine_action] != :run_command
               # If the container is NOT created yet, then do some setup steps
               # necessary for creating it.
-              b2.use Call, IsState, :not_created do |env2, b3|
+              b2.use Call, IsState, :preparing do |env2, b3|
                 if env2[:result]
                   b3.use EnvSet, port_collision_repair: true
                   b3.use HostMachinePortWarning
@@ -271,6 +274,7 @@ module VagrantPlugins
                 end
               end
             else
+              # We're in a run command, so we do things a bit differently.
               b2.use SyncedFolders
               b2.use Create
             end
@@ -294,6 +298,7 @@ module VagrantPlugins
       autoload :HostMachineRequired, action_root.join("host_machine_required")
       autoload :HostMachineSyncFolders, action_root.join("host_machine_sync_folders")
       autoload :HostMachineSyncFoldersDisable, action_root.join("host_machine_sync_folders_disable")
+      autoload :InitState, action_root.join("init_state")
       autoload :IsBuild, action_root.join("is_build")
       autoload :IsHostMachineCreated, action_root.join("is_host_machine_created")
       autoload :Login, action_root.join("login")

plugins/providers/docker/action/host_machine_sync_folders.rb

@@ -46,7 +46,6 @@ module VagrantPlugins
         def setup_synced_folders(host_machine, env)
           # Write the host machine SFID if we have one
           id_path   = env[:machine].data_dir.join("host_machine_sfid")
-          host_sfid = nil
           if !id_path.file?
             host_sfid = SecureRandom.uuid
             id_path.open("w") do |f|

plugins/providers/docker/action/init_state.rb

@@ -0,0 +1,20 @@
+module VagrantPlugins
+  module DockerProvider
+    module Action
+      class InitState
+        def initialize(app, env)
+          @app = app
+        end
+
+        def call(env)
+          # We set the ID of the machine to "preparing" so that we can use
+          # the data dir without it being deleted with the not_created state.
+          env[:machine].id = nil
+          env[:machine].id = "preparing"
+
+          @app.call(env)
+        end
+      end
+    end
+  end
+end

plugins/providers/docker/provider.rb

@@ -156,6 +156,11 @@ module VagrantPlugins
         state_id = driver.state(@machine.id) if @machine.id && !state_id
         state_id = :unknown if !state_id
 
+        # This is a special pseudo-state so that we don't set the
+        # NOT_CREATED_ID while we're setting up the machine. This avoids
+        # clearing the data dir.
+        state_id = :preparing if @machine.id == "preparing"
+
         short = state_id.to_s.gsub("_", " ")
         long  = I18n.t("docker_provider.status.#{state_id}")