TrueMail

Name	Description	Required	Default Value
VERIFIER_EMAIL	Must be an existing email on behalf of which verification will be performed	Yes
VERIFIER_DOMAIN	Must be an existing domain on behalf of which verification will be performed.	No	verifier domain based on verifier email
EMAIL_PATTERN	You can override default regex pattern	No	/(?=\A.{6,255}\z)(\A([\p{L}0-9]+[\w\p{L}.+!~,’&%#*^`{}
SMTP_ERROR_BODY_PATTERN	You can override default regex pattern	No	/(?=.550)(?=.(user
CONNECTION_TIMEOUT	Connection timeout in seconds.	No	2
RESPONSE_TIMEOUT	A SMTP server response timeout in seconds.	No	2
CONNECTION_ATTEMPTS	Total of connection attempts. This parameter uses in mx lookup timeout error and smtp request (for cases when there is one mx server).	No	2
WHITELISTED_EMAILS	You can predefine which type of validation will be used for domains. Also you can skip validation by domain. Available validation types: :regex, :mx, :mx_blacklist, :smtp This configuration will be used over current or default validation type parameter All of validations for ‘somedomain.com’ will be processed with regex validation only. And all of validations for ‘otherdomain.com’ will be processed with mx validation only. It is equal to empty hash by default. config.validation_type_for = { ‘somedomain.com’ => :regex, ‘otherdomain.com’ => :mx } Optional parameter. Validation of email which contains whitelisted emails always will return true. Other validations will not processed even if it was defined in validation_type_for	No
BLACKLISTED_EMAILS	Validation of email which contains blacklisted emails always will return false. Other validations will not processed even if it was defined in validation_type_for	No	It is equal to empty array by default.
WHITELISTED_DOMAINS	Validation of email which contains whitelisted domain always will return true. Other validations will not processed even if it was defined in validation_type_for	No	It is equal to empty array by default.
BLACKLISTED_DOMAINS	Validation of email which contains blacklisted domain always will return false. Other validations will not processed even if it was defined in validation_type_for	No	It is equal to empty array by default.
WHITELIST_VALIDATION	With this option Truemail will validate email which contains whitelisted domain only, i.e. if domain whitelisted, validation will passed to Regex, MX or SMTP validators. Validation of email which not contains whitelisted domain always will return false.	No	FALSE
BLACKLISTED_MX_IP_ADDRESSES	With this option Truemail will filter out unwanted mx servers via predefined list of ip addresses. It can be used as a part of DEA (disposable email address) validations.	No	It is equal to empty array by default.
DNS	This option will provide to use custom DNS gateway when Truemail interacts with DNS. Valid port numbers are in the range 1-65535. If you won’t specify nameserver’s ports Truemail will use default DNS TCP/UDP port 53. By default Truemail uses DNS gateway from system settings and this option is equal to empty array.
NOT_RFC_MX_LOOKUP_FLOW	This option will provide to use not RFC MX lookup flow. It means that MX and Null MX records will be cheked on the DNS validation layer only.	No	By default this option is disabled.
SMTP_PORT	SMTP port number.	No	25
SMTP_FAIL_FAST	This option will provide to use smtp fail fast behavior. When smtp_fail_fast = true it means that Truemail ends smtp validation session after first attempt on the first mx server in any fail cases (network connection/timeout error, smtp validation error). This feature helps to reduce total time of SMTP validation session up to 1 second.	No	By default this option is disabled.
SMTP_SAFE_CHECK	This option will be parse bodies of SMTP errors. It will be helpful if SMTP server does not return an exact answer that the email does not exist	No	By default this option is disabled, available for SMTP validation only.