DE-1146 Release v5

[vtopc]

Breaking changes:

Mailgun client is now domain agnostic

• No need to pass the domain into the func mailgun.NewMailgun
• Many methods now require passing a domain, which indicates which methods are domain-specific and which are global for your account.
  • Pay attention to that func NewMessage(domain, from, subject, text string, to ...string) has a variadic to argument, so there would be no compile error if you miss passing domain.

Types and mocks

• API requests, responses, and helper types are moved into github.com/mailgun/mailgun-go/v5/mtypes package.
• Event interface and parsers moved to github.com/mailgun/mailgun-go/v5/events
• mocks moved to github.com/mailgun/mailgun-go/v5/mocks to address Remove dependency on github.com/go-chi/chi/v5 (again) #322 and Why does this depend on chi? #332

Messages

• Send() and ReSend() methods now returns mtypes.SendMessageResponse.
• Deprecated NewMessage() and NewMIMEMessage() have been removed, use relative funcs.
• Deprecated GetStoredMessageForURL method has been removed.
• Deprecated GetStoredMessageRawForURL method has been removed.

Validation

• Deprecated NewEmailValidator and NewEmailValidatorFromEnv are removed, use ValidateEmail(...) method of Mailgun.
• Deprecated IsValid field is removed from the response; use Risk.

Subaccounts

• Deprecated SubaccountDetails(ctx context.Context, subaccountId string) method is removed, use GetSubaccount(ctx context.Context, subaccountID string).

Domains

• Deprecated func UpdateDomainTrackingWebPrefix is removed, use func UpdateDomain.
• Deprecated func VerifyDomain is removed, use func VerifyAndReturnDomain.
• Deprecated field CreateDomainOptions.IPS is removed, use CreateDomainOptions.IPs.
• ListEventsWithDomain(opts *ListEventOptions, domain string) -> ListEvents(domain string, opts *ListEventOptions).

Metrics

• The deprecated field ESPBlockCount has been removed. Use TemporaryFailedESPBlockCount.

IPs

• Deprecated ListDomainIPS(...) is removed, use ListDomainIPs(...).
• Deprecated ListIPS(ctx context.Context, dedicated bool) is removed, use ListIPs(ctx context.Context, dedicated, enabled bool) (has new enabled argument).

Webhooks

• Deprecated VerifyWebhookRequest method has been removed.

Other changes

These changes might be breaking in some cases.

• Send(ctx context.Context, m Message) method now accepts the Message interface instead of a pointer to struct.

• SetAPIBase() method now returns an error.

• For the EU: do mg.SetAPIBase(mailgun.APIBaseEU) instead of mg.SetAPIBase("https://api.eu.mailgun.net/v...").

• The Webhook Signing Key is now optional and does not relate to the API key. If it is not set(by SetWebhookSigningKey(webhookSigningKey string) method), don't call the VerifyWebhookSignature() method, as it will always fail.

• mailgun.MailgunImpl is renamed to mailgun.Client for not stuttering.