Crate millionsend 

Official Rust SDK for MillionSend — a self-hostable, Resend-compatible email API.

Construct a MillionSend once and reuse it (it is cheap to Clone). Each resource hangs off a public field: emails, batch, contacts, topics, broadcasts, segments, suppressions, domains, webhooks, api_keys, templates, deliverability, usage.

use millionsend::{MillionSend, SendEmailOptions};

let ms = MillionSend::with_base_url("ms_123", "https://mail.acme.dev");
let sent = ms
    .emails
    .send(&SendEmailOptions {
        from: "Acme <onboarding@acme.dev>".into(),
        to: "delivered@resend.dev".into(),
        subject: "Hello".into(),
        html: Some("<strong>it works</strong>".into()),
        ..Default::default()
    })
    .await?;
println!("sent {}", sent.id);

Fallible calls return Result<T, Error>; Error::Api carries the API’s { statusCode, name, message }, Error::Http a transport failure (its status_code is None).

Structs

AddContactSegmentResponse

AddSuppressionOptions

origin defaults to manual server-side.

ApiError

The API’s canonical error shape ({ statusCode, name, message }), plus the client-side conditions that never reached the API, which carry status_code: None. Mirrors Resend’s ErrorResponse, so code that switches on name ports across unchanged.

ApiKey

ApiKeyToken

The token is shown once, at creation.

ApiKeys

API keys. Mirrors Resend’s api_keys resource.

Attachment

An attachment. content is base64; path is passed through so the API, not the SDK, decides whether remote attachments are accepted.

Batch

Batch send. Mirrors Resend’s batch resource.

BatchAddSuppressionOptions

Up to 1000 addresses; duplicates collapse.

BatchAddSuppressionResponse

BatchContactResult

BatchContactsCounts

Per-status totals; they sum to the request length.

BatchContactsOptions

BatchContactsResponse

BatchError

A per-item failure from a permissive batch, addressed by request index.

BatchRemoveSuppressionsResponse

BatchResponse

errors is only populated under BatchValidation::Permissive.

Broadcast

BroadcastId

BroadcastListItem

Broadcasts

Broadcasts — a one-off email to a segment, a topic’s subscribers, or (with neither set) every contact. Mirrors Resend’s broadcasts resource.

CancelBroadcastResponse

CancelEmailResponse

Contact

ContactAddress

Address a contact by id or email (email wins when both are set). A bare &str/String is treated as an id.

ContactId

ContactListItem

ContactProperties

Typed definitions for the keys of contact.properties (/contact-properties).

ContactProperty

ContactPropertyId

ContactSegments

Manual segment membership for one contact.

ContactTopicUpdate

ContactTopics

Per-contact topic subscriptions (opt a contact in/out of a topic).

Contacts

Contacts — team-global, addressable by id or email (email wins). Mirrors Resend’s contacts resource, plus nested topics, segments and properties.

CreateApiKeyOptions

permission defaults to full_access; domain_id restricts a sending_access key to one domain.

CreateBroadcastOptions

CreateContactOptions

Build with CreateContactOptions::new(email). Contacts are team-global; duplicates (case-insensitive email) are a 409 validation_error.

CreateContactPropertyOptions

fallback_value is Some(Value::Null) to store an explicit null; its JSON type must match type.

CreateDomainOptions

region is a plain string because each deployment serves its own SES region and rejects any other with 422; omit it to use the deployment’s.

CreateEmailResponse

CreateSegmentOptions

filter: None creates a manual-membership segment, fed only by contacts.segments.add and contacts.create’s segments.

CreateTemplateOptions

from, reply_to and variables are passed through so the API, not the SDK, decides whether they are supported (422 while not).

CreateTopicOptions

CreateWebhookOptions

events are wire names (email.delivered, deliverability.paused, …), kept as strings because the catalog grows. signing_secret is optional: omit it to have one minted; pass whsec_… to reuse an existing one.

CreateWebhookResponse

DeleteBroadcastResponse

DeleteContactResponse

DeleteSegmentResponse

DeleteTopicResponse

Deleted

{ object, id, deleted: true } — the envelope every delete returns.

Deliverability

Account-level deliverability score over the trailing window.

DeliverabilityReport

GET /deliverability — the account score over the trailing window. Scores are 0–10 with one decimal; None means not enough data to compute.

Domain

DomainCapabilities

DomainRecord

Domains

Sending domains and their DNS records. Mirrors Resend’s domains resource.

Email

EmailInsights

GET /emails/:id/insights — the pre-send best-practice report computed when the email was sent.

EmailListItem

GET /emails item — the summary without bodies, message_id or score.

Emails

Transactional email. Mirrors Resend’s emails resource.

Idempotent

A request body paired with an optional Idempotency-Key. Any body converts implicitly (ms.emails.send(&email)); attach a key with with_idempotency_key.

InsightCheck

One check from the insights report. id is an open catalog that grows across score versions; severity/status stay plain strings for the same reason band does.

List

The { object: "list", data, has_more } envelope every paginated list returns.

ListOptions

Keyset pagination for list calls. after/before are mutually exclusive UUID cursors; limit is 1–100 (server default 20).

ListSuppressionsOptions

ListOptions plus an optional origin filter.

MillionSend

The MillionSend client. Construct once and reuse.

RemoveContactSegmentResponse

Segment

SegmentCondition

SegmentFilter

SegmentRef

{ id } — a segment referenced from a contact payload.

Segments

Dynamic segments — a saved filter over the team’s contacts (MillionSend extension, no Resend equivalent). get returns a live contact_count.

SendEmailOptions

Build with SendEmailOptions::new(from, to, subject) then set the rest, or a struct literal with ..Default::default().

Suppression

SuppressionId

Suppressions

Suppression list — addresses the team never sends to. Mirrors Resend’s suppressions resource; entries are addressable by id or email.

Tag

Template

TemplateId

TemplateListItem

Templates

Reusable email templates, addressable by id or alias. Mirrors Resend’s templates resource; templates are always published, so publish is a compatibility no-op.

Topic

TopicId

TopicList

GET /topics returns every topic at once (has_more is always false), so there are no cursors to expose.

Topics

Subscription topics — granular unsubscribe categories for a team.

UpdateBroadcastOptions

Fields default to “leave unchanged”. To detach the topic set clear_topic_id: true, which puts "topic_id": null on the wire.

UpdateContactOptions

Fields default to “leave unchanged”. For first_name/last_name, Some(Some(v)) sets, Some(None) clears the field (sends null), and None omits it.

UpdateContactPropertyOptions

None leaves the fallback unchanged; Some(Value::Null) clears it.

UpdateContactTopicsResponse

UpdateDomainOptions

tracking_subdomain: Some(Some(label)) sets, Some(None) clears (sends null), None leaves it. tls/capabilities are passed through so the API, not the SDK, decides whether they are supported (422 while not).

UpdateEmailOptions

PATCH /emails/:id — reschedule a not-yet-sent email.

UpdateEmailResponse

UpdateSegmentOptions

filter: Some(Some(f)) replaces the filter, Some(None) clears it (sends null, turning the segment manual-membership-only), None leaves it.

UpdateTemplateOptions

For subject/text/alias, Some(Some(v)) sets, Some(None) clears (sends null), None leaves the field unchanged.

UpdateTopicOptions

UpdateWebhookOptions

Usage

Plan limits and today’s send count (MillionSend extension).

UsageLimits

None = unlimited (or self-hosted).

UsageReport

GET /usage — plan limits and today’s send count. Self-hosted instances report cloud: false with plan: None and null limits.

UsageTeam

UsageToday

Webhook

WebhookId

Webhooks

Webhook endpoints. Mirrors Resend’s webhooks resource.

Enums

ApiKeyPermission

BatchContactStatus

BatchRemoveSuppressionOptions

Remove by addresses or by suppression ids (up to 1000 either way); serializes as { "emails": [...] } or { "ids": [...] }.

BatchValidation

x-batch-validation on batch endpoints. Strict (the server default) rejects the whole batch when one item is invalid; Permissive accepts the valid subset and lists the rest under errors.

ContactPropertyType

Error

Every fallible SDK call resolves to Result<T, Error>.

OnConflict

on_conflict for POST /contacts/batch: what happens to an item whose email already belongs to a contact (or repeats inside the batch).

Recipients

A recipient field that accepts a single address or a list — serializes as a bare string or a JSON array to match the wire’s string | string[].

SegmentMatch

SuppressionOrigin

TopicSubscription

TopicVisibility

WebhookStatus

Traits

IdempotentTrait

Resend’s idempotency shape: ms.emails.send(email.with_idempotency_key("k")) and ms.batch.send(emails.with_idempotency_key("k")).

Type Aliases

DeleteApiKeyResponse

DeleteContactPropertyResponse

DeleteDomainResponse

DeleteEmailResponse

DeleteSuppressionResponse

DeleteTemplateResponse

DeleteWebhookResponse

Result

Shorthand for std::result::Result<T, millionsend::Error>.