Contacts, Calendar & Labels Contacts Contacts CRUD operations for contacts and contact emails via /contacts/v4 . Operations Get Contacts // Single contact by ID contact, err := c.GetContact(ctx, contactID) // Count contacts count, err := c.CountContacts(ctx) // Paginated listing contacts, err := c.GetContacts(ctx, page, pageSize) // Auto-paginating - get all allContacts, err := c.GetAllContacts(ctx) // Auto-paginating with custom page size allContacts, err := c.GetAllContactsPaged(ctx, pageSize) Search by Email // Count matches count, err := c.CountContactEmails(ctx, "user@example.com") // Paginated search emails, err := c.GetContactEmails(ctx, "user@example.com", page, pageSize) // Get all matching allEmails, err := c.GetAllContactEmails(ctx, "user@example.com") Create / Update / Delete // Bulk create with overwrite and label options results, err := c.CreateContacts(ctx, proton.CreateContactsReq{ Contacts: []proton.Contact{ { Cards: []proton.ContactCard{...}, Email: "user@example.com", }, }, }) // Update a contact updated, err := c.UpdateContact(ctx, contactID, proton.UpdateContactReq{ Cards: []proton.ContactCard{...}, }) // Bulk delete err := c.DeleteContacts(ctx, proton.DeleteContactsReq{ IDs: []string{id1, id2}, }) Per-Contact Encryption Preferences Contact settings are stored as VCard-embedded X-PM-* fields: // Get encryption settings for a contact settings := contact.GetSettings() // Returns: MIME type, PGP scheme (inline/MIME), sign/encrypt flags, PGP keys // Set encryption settings contact.SetSettings(proton.ContactSettings{ MIMEType: "text/plain", Scheme: proton.PGPMIMEScheme, Sign: true, Encrypt: true, EncryptUntrusted: true, PGPKeys: []proton.PGPKey{...}, }) Key Types Type Description Contact Composite of ContactMetadata and ContactCards ContactMetadata ID, name, UID, size, timestamps, emails, labels ContactCards VCard data for the contact ContactEmail Email entry with ID, name, email string, type tags, contactID, labels ContactSettings Per-contact encryption preferences (MIME type, scheme, sign/encrypt flags, PGP keys) RecipientType Internal vs external recipient classification Calendar Calendar Calendar and calendar event retrieval via /calendar/v1 . Includes key management for encrypted calendar data. Operations Calendars // List all calendars calendars, err := c.GetCalendars(ctx) // Get a single calendar cal, err := c.GetCalendar(ctx, calendarID) // Get encryption keys for a calendar keys, err := c.GetCalendarKeys(ctx, calendarID) // Get shared calendar members members, err := c.GetCalendarMembers(ctx, calendarID) // Get passphrase for calendar key decryption passphrase, err := c.GetCalendarPassphrase(ctx, calendarID) Calendar Events // Count events count, err := c.CountCalendarEvents(ctx, calendarID) // Paginated listing with optional filters events, err := c.GetCalendarEvents(ctx, calendarID, page, pageSize, filter) // Auto-paginating - get all events allEvents, err := c.GetAllCalendarEvents(ctx, calendarID, filter) // Single event by ID event, err := c.GetCalendarEvent(ctx, calendarID, eventID) Decryption Calendar events use two-layer encryption : Calendar keys (passphrase-locked) Shared events add a second layer of sharing key packets // Unlock calendar keys with passphrase keyRing, err := keys.Unlock(passphrase) // Decrypt individual event parts decoded, err := eventPart.Decode(calKR, addrKR, keyPacket) // Handles both two-layer decryption and PGP signature verification Key Types Type Description Calendar ID, name, description, color, display flag, type (normal/subscribed), flags CalendarKey Encrypted private key with Unlock(passphrase) returning *crypto.Key CalendarKeys Slice of keys with Unlock(passphrase) returning *crypto.KeyRing CalendarMember ID, permissions, email, color, display, calendarID CalendarPassphrase Encrypted passphrase with Decrypt(memberID, addrKR) for decryption CalendarEvent UID, start/end times, timezone, full-day flag, author, attendees, encrypted parts CalendarEventPart Individual part with type (clear/encrypted/signed), data, signature, author EventAction Delete, Create, Update, UpdateFlags PGP Signature Verification Encrypted calendar parts can also be signed. The Decode method verifies signatures using the address keyring. Labels & Addresses Labels Label (category/folder) management via /core/v4/labels . Operations // Fetch labels filtered by type(s) labels, err := c.GetLabels(ctx, proton.LabelLabel, proton.LabelFolder) // Find a specific label by ID label, err := c.GetLabel(ctx, labelID, proton.LabelLabel) // Create a label label, err := c.CreateLabel(ctx, proton.CreateLabelReq{ Name: "Personal", Color: "#ff0000", Type: proton.LabelLabel, Parent: parentID, }) // Update a label err := c.UpdateLabel(ctx, labelID, proton.UpdateLabelReq{ Name: "Updated Name", Color: "#00ff00", }) // Delete a label err := c.DeleteLabel(ctx, labelID) System Label Constants Constant ID Description InboxLabel "0" Inbox AllSentLabel "2" All Sent TrashLabel "3" Trash SpamLabel "4" Spam AllMailLabel "5" All Mail StarredLabel "10" Starred Email Addresses Email address management via /core/v4/addresses . Operations // List addresses (sorted by order) addresses, err := c.GetAddresses(ctx) // Get a single address addr, err := c.GetAddress(ctx, addressID) // Reorder addresses err := c.OrderAddresses(ctx, proton.OrderAddressesReq{...}) // Enable/disable address err := c.EnableAddress(ctx, addressID) err := c.DisableAddress(ctx, addressID) // Delete address err := c.DeleteAddress(ctx, addressID) Address Types Type Description Original Original Proton address Alias Proton alias Custom Custom domain address Premium Premium address External Bring Your Own Email (BYOE) BYOE Detection if addr.IsBYOEAddress() { // External type with sending enabled } Key Types Type Description Label ID, parentID, name, path ([]string), color, type LabelType Label, ContactGroup, Folder, System Address ID, email, send/receive flags, status, type, order, display name, keys AddressStatus Disabled, enabled, deleting AddressType Original, alias, custom, premium, external Path Handling The API sends label path as a string (e.g., "Inbox/SubFolder" ), which is split into a []string slice for Go use, with custom MarshalJSON / UnmarshalJSON .