Working with Triggers

1. Defining Before Triggers

Trigger Type	Description	Usage
trigger.before	Executes before a specific Vagrant action	`config.trigger.before :up, :provision do \|trigger\|`

Example: Defining a Before Trigger

config.trigger.before :up, :provision do |trigger|
  trigger.name = "Check dependencies"
  trigger.run = { path: "check-deps.sh" }
end

Note: Before triggers run before the specified action and can be used to validate prerequisites or prepare the environment.

2. Defining After Triggers

After triggers in Vagrant execute after a specific action has completed. They are defined using the trigger block within the Vagrantfile.

Property	Description	Values
trigger.after	Specifies the action after which the trigger should run	`:up`, `:provision`, `:reload`, `:destroy`
trigger.name	Unique identifier for the trigger	String
trigger.execute	Command or script to execute	String or block

Example: After Provision Trigger

vagrant.trigger.after :provision do
  puts "Provisioning completed!"
end

Note: Triggers are executed in the context of the Vagrant environment and can access Vagrant's API.

3. Running Commands

Command	Description	Example
vagrant trigger run	Executes triggers defined in the Vagrantfile	`vagrant trigger run`
vagrant trigger run --name <trigger_name>	Runs a specific trigger by name	`vagrant trigger run --name provision`

Example: Trigger Configuration

Vagrant.configure("2") do |config|
  config.trigger.after :up, "echo 'Provisioning complete'"
end

4. Running Inline Scripts

Property	Description	Example
trigger	Defines a trigger that runs an inline script	`trigger :inline, "echo 'Running inline script'"`
on	Specifies the event that activates the trigger	`on :create, :update`
inline	Specifies the inline script to execute	`inline "echo 'Hello from Vagrant'"`

Example: Running a Script on VM Creation

config.trigger.after :up do
  run "echo 'VM is up and running'"
end

Example: Inline Script with Variable Substitution

config.trigger.before :provision do
  run "echo 'Provisioning started at: $(date)'"
end

5. Setting Trigger Conditions

Condition Type	Description	Example
on	Specifies the event that triggers the action	`"on" : "provision"`
if	Boolean expression to evaluate before running the trigger	`"if" : "machine.state == 'running'"`
unless	Opposite of `if`, runs only if condition is false	`"unless" : "machine.state == 'not_created'"`

Example: Trigger on Provision

Vagrant.configure("2") do |config|
  config.trigger.after :provision, "echo 'Provisioning complete'"
end

Example: Conditional Trigger

Vagrant.configure("2") do |config|
  config.trigger.after :up, "echo 'Machine is up'" do
    if "machine.state == 'running'"
  end
end

6. Using Trigger Names

Trigger Name	Description	Usage
vagrant.up	Triggered when 'vagrant up' is executed	`vagrant trigger --target vagrant.up --action "echo 'Provisioning started'"`
vagrant.halt	Triggered when 'vagrant halt' is executed	`vagrant trigger --target vagrant.halt --action "echo 'Machine halted'"`
vagrant.destroy	Triggered when 'vagrant destroy' is executed	`vagrant trigger --target vagrant.destroy --action "echo 'Machine destroyed'"`
vagrant.provision	Triggered when 'vagrant provision' is executed	`vagrant trigger --target vagrant.provision --action "echo 'Provisioning complete'"`
vagrant.reload	Triggered when 'vagrant reload' is executed	`vagrant trigger --target vagrant.reload --action "echo 'Machine reloaded'"`

Example: Using Trigger Names in Vagrantfile

trigger&#x20;:vagrant.up&#x20;do&#x20;|
  on_success&#x20;"echo&#x20;'Vagrant&#x20;up&#x20;triggered'"
end

trigger&#x20;:vagrant.halt&#x20;do&#x20;|
  on_success&#x20;"echo&#x20;'Vagrant&#x20;halt&#x20;triggered'"
end

7. Configuring Ignore Errors

Option	Values	Description
ignore_errors	`true` \| `false`	When set to `true`, Vagrant will continue executing subsequent triggers even if a previous trigger fails. Defaults to `false`.

Example: Setting ignore_errors to true

Vagrant.configure("2") do |config|
  config.trigger.after :up, :ignore_errors => true do
    run "echo 'This will run even if previous trigger failed'"
  end
end

Note: Setting ignore_errors to true allows for more resilient automation but should be used carefully as it can mask issues that need attention.

8. Setting Abort on Error

Option	Values	Description
trigger.abort_on_error	`true` \| `false`	If set to `true`, the trigger will abort the Vagrant operation if any error occurs during execution. Defaults to `false`.

Example: Configuring Abort on Error

Vagrant.configure("2") do |config|
  config.trigger.after :up, abort_on_error: true do
    run "echo 'Provisioning completed successfully'"
  end
end

9. Using Info Messages

Info messages in Vagrant are used to display informational content to users during the provisioning process. These messages do not halt execution and are useful for providing context or status updates.

Option	Values	Description
trigger.info	`string`	Displays an informational message to the user during provisioning.

Example: Displaying an Info Message

Vagrant.configure("2") do |config|
  config.trigger.after :up, :info => "Provisioning complete!" do
    run :local => "echo 'Vagrant up completed.'"
  end
end

10. Executing Ruby Code

Property	Description	Example
trigger	Defines a trigger block in Vagrantfile	`vagrant.trigger.after :up do \|trigger\| trigger.exec "echo 'Provisioning complete'" end`
trigger.exec	Executes a shell command or Ruby code	`trigger.exec "ruby -e 'puts ENV[\\"VAGRANT_ENV\\"]'\""`
trigger.exec Ruby	Executes inline Ruby code	`trigger.exec "ruby -e \\"puts 'Hello from Ruby'\\""`

Example: Executing Ruby Code in Trigger

vagrant.trigger.after :up do |trigger|
  trigger.exec "ruby -e 'puts ENV[\\"VAGRANT_ENV\\"]'\""
end

Note: Ruby code must be properly escaped when passed as a string to trigger.exec.