Amarula (amarula v0.2.2)
View SourceAmarula — a WhatsApp Web client for Elixir.
Connect to WhatsApp the way the web/desktop app does: pair once by scanning a
QR code with your phone, then send and receive messages from Elixir. Every call
takes a conn handle, so you can run many accounts at once — there is no global
connection.
Quick start
Pair a device (first run), then send a message:
# 1. Start a connection. Events (the QR code, incoming messages) are sent
# to `parent_pid` — here, the current process.
{:ok, conn} =
Amarula.new(%{profile: :me})
|> Amarula.connect(parent_pid: self())
# 2. On the first run you get a QR code to scan with your phone:
# WhatsApp → Settings → Linked Devices → Link a device.
receive do
{:amarula, :connection_update, %{qr: qr}} when is_binary(qr) ->
IO.puts(qr) # render this string as a QR code
end
# 3. Once linked you get an :open update — now you can send.
receive do
{:amarula, :connection_update, %{connection: :open}} -> :ready
end
Amarula.send_text(conn, "5511999999999@s.whatsapp.net", "hello from Elixir!"):profile names this account's stored credentials, so the next run reconnects
without a new QR. Amarula.new/1 fills in all protocol defaults; you usually
pass only :profile. For a ready-made supervised wrapper, see
Amarula.Examples.Connection.
Testing your bot
To test your message-handling logic without a real WhatsApp connection, use
Amarula.Testing — it starts an offline connection and lets you deliver
synthetic inbound messages that flow through the real receive pipeline.
The QR code
The qr in a :connection_update is a plain string — you turn it into a
scannable image, with whatever you like (a terminal renderer, a qr_code
PNG, an HTML <img>, …). There is no built-in renderer and no login-phase
plugin hook: rendering is entirely the consumer's, via this event. (The
handshake/pairing crypto is deliberately closed to plugins — the send/receive
pipelines run only after a message is decrypted.)
The string is four comma-separated fields:
"<ref>,<noiseKeyB64>,<identityKeyB64>,<advSecretKeyB64>"ref— a server-issued pairing reference (from the<pair-device>IQ); it rotates every ~20s, so each rotation emits a fresh:connection_updatewith a newqr— re-render on each.noiseKeyB64— our Noise static public key (base64).identityKeyB64— our signed identity public key (base64).advSecretKeyB64— the companion adv secret key (base64).
The phone reads our public keys + ref from the image to link the device. Render
it as-is — don't reformat the string. Example with qr_code (note its API is
Result-tuple based — create/1 returns {:ok, qr} and render/2 takes that
tuple, so you pipe straight through):
{:amarula, :connection_update, %{qr: qr}} when is_binary(qr) ->
qr |> QRCode.create() |> QRCode.render(:png) |> QRCode.save("qr.png")Addressing
A send target is a jid string — "<number>@s.whatsapp.net" for a person,
"<id>@g.us" for a group — or an Amarula.Address (use Amarula.Address.pn/1
to build one from a bare number).
Sending
All sends return {:ok, msg_id} or {:error, reason}:
Amarula.send_text(conn, jid, "hello")
Amarula.send_media(conn, jid, :image, image_bytes, caption: "hi")
Amarula.send_reaction(conn, message_key, "👍") # "" removes the reaction
Amarula.send_edit(conn, message_key, "fixed typo")
Amarula.send_revoke(conn, message_key) # delete for everyoneA message_key is the key field of a message you received (see below) —
that's how you point a reaction/edit/delete at a specific message.
Receiving
Incoming events arrive at parent_pid as {:amarula, type, data} tuples (the
full list is in event/0). The main one is :messages_upsert, whose data
carries [%Amarula.Msg{}] — the consumer-friendly message view (type +
content), never the raw protobuf. Match on msg.type; for media, fetch the
bytes lazily with download_media/1.
What Amarula does NOT store
Amarula keeps only what the protocol needs (credentials, Signal sessions,
device/LID mappings). It is not a message archive and keeps no chat or
DM list: there is no "list my conversations" call, and incoming messages are
delivered once via :messages_upsert and then forgotten. If your app needs an
inbox, a contact list, or scrollback, persist it yourself from the events —
Amarula won't do it for you.
History sync (:history_sync events, and fetch_history/4 to pull more on
demand) delivers WhatsApp's own history to you the same way — as events to
store, not a queryable archive Amarula maintains. resolve_quoted/2 is the one
read-back helper, and only for a reply's quoted message you still hold.
Summary
Types
Events delivered to parent_pid as {:amarula, type, data}
A send target: an Amarula.Address or a jid string ("<n>@s.whatsapp.net" / "<id>@g.us").
A media kind handled by send_media/5.
A raw message key — used by the low-level on-demand history request.
A reference to a specific existing message (for reactions / edits / deletes / poll votes). Either
A connection's profile name (its identity + storage scope).
Result of a send: the assigned message id, or an error.
Functions
Start a built Amarula.Conn and begin connecting. Returns the running conn
handle (a pid). Pair with new/1
Current connection state (e.g. :disconnected, :connecting, :connected).
Close the connection's websocket without taking the supervision tree down.
Pair with reconnect/1 to bring it back up; use stop/1 to release the
profile entirely. Returns :ok | {:error, reason}.
Download + decrypt an incoming media file. Inbound messages carry only media
metadata (directPath/mediaKey), not the bytes — call this to fetch them
lazily, passing a %Amarula.Msg{type: :media} (or its content.media struct
Ask the phone for older history of a chat (a PEER_DATA_OPERATION on-demand
request). oldest_key is the oldest message you already have, oldest_ts its
millisecond timestamp, and count how many older messages to request. The
history arrives asynchronously later via the normal :history_sync event.
Returns {:ok, request_msg_id} or {:error, :not_authenticated}.
Keep a message in a disappearing chat (exempt it from auto-delete). ref is a
%Amarula.Msg{} or {jid, msg_id}.
List every profile that has stored credentials in storage.
Like list_profiles/1, but each entry carries the logged-in identity read from
that profile's stored creds — for building a friendlier account picker
Send a read receipt for message_ids in chat jid (pass participant for a
group sender). Marks those messages read on the sender's side.
Build a connection value (Amarula.Conn) from config, without starting it.
This connection's own identity as an Amarula.Address — our phone-number address,
carrying our companion device id (creds.me.id).
Whether msg is in our own chat (the "Message Yourself" chat): from_me and
addressed to our own account. The check a self-chat command channel needs — drive
an agent by messaging yourself.
Pin a message for everyone in the chat. ref is a %Amarula.Msg{} or {jid, msg_id}.
(Re)open the connection's websocket on an already-started connection — the
inverse of disconnect/1. Runs the handshake and logs in again with the
profile's stored credentials. Returns :ok | {:error, reason}.
Request a link-code (phone-number) pairing code for phone (E.164 digits;
any +, spaces, or dashes are stripped).
Resolve the original message a reply quotes.
Send an album (grouped media) to jid. items is a list of
{type, data, opts} (same shape as send_media/5), where type is :image
or :video. Sends the album parent first, then each item referencing it.
Send a typing indicator to jid: :composing, :recording, or :paused.
Send a contact (display_name + vCard string) to jid.
Send multiple contacts to jid: pairs is [{display_name, vcard}, ...].
Edit a message we sent, replacing its text. ref is a %Amarula.Msg{} or a
{jid, msg_id} tuple.
Send an event to jid (a group or 1:1). name is the title. opts:
:description, :location ({lat, lng} or [lat:, lng:, name:, address:]),
:join_link, :start_time / :end_time (unix seconds), :extra_guests_allowed.
Send a group-invite message to jid — a tap-to-join card for group_jid using
code (from Amarula.Group.invite_code/2). opts: :group_name, :caption,
:expiration (unix ms).
Send a location to jid. opts: :name, :address, :url, :is_live.
Send media of type (:image/:video/:audio/:document/:sticker).
Send a poll to jid. Returns {:ok, msg_id, message_secret} — keep the
message_secret to tally incoming votes (Amarula.Protocol.Messages.Poll).
opts: :selectable (max picks, default 1), :announcement, :message_secret.
Cast a vote on an existing poll. poll is a message_ref for the poll-creation
message (a %Amarula.Msg{} or {jid, msg_id} tuple); message_secret is the
poll's 32-byte secret (from send_poll/5, or the poll's messageContextInfo);
option_names are the chosen options. The vote is encrypted under the secret.
React to a message with emoji (empty string removes the reaction). ref is a
%Amarula.Msg{} or a {jid, msg_id} tuple.
Delete a message for everyone (revoke). ref is a %Amarula.Msg{} or a
{jid, msg_id} tuple.
Send a 1:1/group text message to jid. opts
Set your global presence: :available (online) or :unavailable. Needs a profile name.
Stop a connection entirely — the whole supervision tree — and release its profile so it can be started again (here or, with a cluster registry, on another node).
Subscribe to a contact's presence updates.
Undo a previous keep (let the message disappear again). ref is a %Amarula.Msg{} or {jid, msg_id}.
Unpin a previously pinned message. ref is a %Amarula.Msg{} or {jid, msg_id}.
A :via handle for profile — usable anywhere a conn() is accepted, so calls
route to whatever pid currently holds the profile (restart-safe). Assumes the
default registry; for a custom one, build it from the Conn via
Amarula.ProfileRegistry.via/2.
The live connection pid for profile, or nil. A restart-safe handle: the pid
changes if the connection restarts, but the profile resolves to the current one.
As whereis/1, but resolves through conn_or_config's :registry.
Destructively forget this connection's profile: unlink the companion on WhatsApp's side (the phone drops the device), wipe all local storage for it (creds, sessions, keys, mappings), then disconnect. After this the profile must be re-paired to use again.
Types
@type conn() :: GenServer.server()
A connection handle: the pid from connect/2, a registered name, or the :via
tuple from via/1 (resolve a profile to a restart-safe handle with whereis/1).
@type event() ::
:connection_update
| :messages_upsert
| :chats_update
| :contacts_update
| :group_update
| :receipt_update
| :presence_update
| :blocklist_update
| :pairing_code
| :pairing_success
| :history_sync
| :error
Events delivered to parent_pid as {:amarula, type, data}:
:connection_update—%{connection: state, qr: qr | nil, ...}(partial map):messages_upsert—%{from: jid, id: id, messages: [%Amarula.Msg{}]}:chats_update—[%Amarula.Chat{}](from history/app-state sync):contacts_update—[%Amarula.Contact{}]:group_update—%{group: Address, author: Address | nil, action: ..}a group membership/metadata change (participant add/remove/promote/demote, subject, announce, lock — seeAmarula.Protocol.Groups.Notification):receipt_update—%{message_ids, from, participant, status, timestamp}a message we sent was delivered/read/played (Amarula.Protocol.Messages.Receipt):presence_update—%{jid: Address, participant: Address, presence, last_seen}a contact/group member's presence (:available/:unavailable) or typing state (:composing/:recording) —Amarula.Protocol.Presence:blocklist_update—[%{jid, action}]block/unblock changes:pairing_code—%{code: code}the 8-char link-code (phone-number) pairing code to display (fromrequest_pairing_code/3):pairing_success—%{jid, lid, platform}(QR) or%{via: :link_code}(phone-number pairing):history_sync— a batch of synced history (chats/contacts/messages) delivered asynchronously after connect (Amarula.Protocol.Messages.HistorySync):error— a connection error term
Credentials are persisted by Amarula itself (scoped to the connection's
:profile), so there is no :creds_update to handle — name a profile and the
next connect reloads its creds automatically.
@type jid() :: String.t() | Amarula.Address.t()
A send target: an Amarula.Address or a jid string ("<n>@s.whatsapp.net" / "<id>@g.us").
@type media_type() :: :image | :video | :audio | :document | :sticker
A media kind handled by send_media/5.
@type message_key() :: Amarula.Protocol.Proto.MessageKey.t()
A raw message key — used by the low-level on-demand history request.
@type message_ref() :: Amarula.Msg.t() | {jid(), String.t()}
A reference to a specific existing message (for reactions / edits / deletes / poll votes). Either:
- the
%Amarula.Msg{}you received (carries its chat, sender, id), or - a
{jid, msg_id}tuple — the chatjidplus the message id string.
Both are self-contained. (Quote replies use the :quoted opt on send_text,
which takes the %Amarula.Msg{} directly.)
A connection's profile name (its identity + storage scope).
Result of a send: the assigned message id, or an error.
Functions
@spec connect( Amarula.Conn.t(), keyword() ) :: {:ok, conn()} | {:error, {:already_running, pid()}} | {:error, term()}
Start a built Amarula.Conn and begin connecting. Returns the running conn
handle (a pid). Pair with new/1:
{:ok, pid} = Amarula.new(config) |> Amarula.connect()The returned pid is not restart-safe
A raw pid is returned on purpose — you can Process.monitor/1 it to detect a
crash, or Process.alive?/1 it. But if the connection crashes, its supervision
tree restarts it under a new pid, and the one returned here then points at a
dead process. So for anything you hold across time (a GenServer state field, a
long-lived process), store the profile and address the connection with
via/1 instead:
conn = Amarula.via(profile) # always resolves to the current pid
Amarula.send_text(conn, jid, "hi")via/1/whereis/1 resolve through Amarula.ProfileRegistry, which the
connection re-registers on every restart. The raw pid is fine for a quick,
short-lived script that won't outlive a crash.
Only one connection per profile may run at a time (within the registry's reach —
one per node by default; see Amarula.ProfileRegistry). Connecting a profile
that's already live returns {:error, {:already_running, pid}} — use whereis/1
to get the existing one.
opts:
:parent_pid— process to receive{:amarula, ..}events (default: caller):name— optional registered name for the connection
Current connection state (e.g. :disconnected, :connecting, :connected).
Close the connection's websocket without taking the supervision tree down.
Pair with reconnect/1 to bring it back up; use stop/1 to release the
profile entirely. Returns :ok | {:error, reason}.
@spec download_media(Amarula.Msg.t()) :: {:ok, binary()} | {:error, term()}
Download + decrypt an incoming media file. Inbound messages carry only media
metadata (directPath/mediaKey), not the bytes — call this to fetch them
lazily, passing a %Amarula.Msg{type: :media} (or its content.media struct
kind). Returns
{:ok, bytes}or{:error, reason}(:bad_macon a failed integrity check).%Amarula.Msg{type: :media} = msg {:ok, bytes} = Amarula.download_media(msg)
@spec download_media(map(), media_type()) :: {:ok, binary()} | {:error, term()}
@spec fetch_history(conn(), message_key(), integer(), non_neg_integer()) :: send_result()
Ask the phone for older history of a chat (a PEER_DATA_OPERATION on-demand
request). oldest_key is the oldest message you already have, oldest_ts its
millisecond timestamp, and count how many older messages to request. The
history arrives asynchronously later via the normal :history_sync event.
Returns {:ok, request_msg_id} or {:error, :not_authenticated}.
@spec keep_message(conn(), message_ref()) :: send_result()
Keep a message in a disappearing chat (exempt it from auto-delete). ref is a
%Amarula.Msg{} or {jid, msg_id}.
@spec list_profiles( Amarula.Storage.Scope.t() | Amarula.Conn.t() | {module(), keyword()} | keyword() ) :: {:ok, [Amarula.Storage.profile()]} | {:error, term()}
List every profile that has stored credentials in storage.
Takes a storage source rather than a live connection: a Amarula.Storage.Scope.t/0,
a built %Amarula.Conn{} (use its scope), or a {adapter, opts} / bare-opts
storage spec (the same value new/1 accepts as :storage). Returns the profile
names that have a :creds entry — what you'd pass as :profile to reconnect.
Amarula.list_profiles(root: "./amarula_data")
#=> {:ok, [:primary, "work"]}{:error, :not_supported} if the storage adapter can't enumerate profiles.
@spec list_profiles_with_metadata( Amarula.Storage.Scope.t() | Amarula.Conn.t() | {module(), keyword()} | keyword() ) :: {:ok, [Amarula.Storage.profile_info()]} | {:error, term()}
Like list_profiles/1, but each entry carries the logged-in identity read from
that profile's stored creds — for building a friendlier account picker:
Amarula.list_profiles_with_metadata(root: "./amarula_data")
#=> {:ok, [%{profile: :primary, jid: "5511...@s.whatsapp.net",
# lid: "12345@lid", name: "Alice"}]}Costs one extra storage read per profile. name/jid/lid are nil for a
profile that hasn't finished pairing. Accepts the same storage sources as
list_profiles/1.
Send a read receipt for message_ids in chat jid (pass participant for a
group sender). Marks those messages read on the sender's side.
@spec new(map()) :: Amarula.Conn.t()
Build a connection value (Amarula.Conn) from config, without starting it.
This is the start of the Req-style builder: attach plugins, then connect/2.
Amarula.new(%{profile: :primary})
|> MyPlugin.attach(opts)
|> Amarula.connect()Connection/protocol defaults are filled in (see Amarula.Config), so config
need only carry :profile (+ :auth and any overrides).
Offline (sandbox) mode
offline: true runs the connection with no socket: it never reaches WhatsApp,
and every send_* short-circuits to {:ok, msg_id} without encrypting or
emitting a frame. Combined with Amarula.Testing.deliver_* (which feeds
synthetic inbound messages), this lets you run your bot end to end — receive a
message, reply to it — with no real-world effect. See Amarula.Testing.
@spec own_address(conn()) :: Amarula.Address.t()
This connection's own identity as an Amarula.Address — our phone-number address,
carrying our companion device id (creds.me.id).
Always returns an Address: before login (no identity yet) it returns
Amarula.Address.empty/0, so you never have to nil-check. own_address(conn).device
is nil for the primary
device / phone, or the linked-device number (e.g. 29) for a companion like this app.
Use it to detect messages this app/device itself sent — e.g. to ignore the agent's own self-chat sends and avoid a feedback loop. This does a call into the connection, and our own device is constant after login, so read it once and reuse the device:
own_device = Amarula.own_address(conn).device
# then, per received message:
if msg.from_me and msg.from.device == own_device do
:ignore # this device sent it
end
@spec own_chat?(conn(), Amarula.Msg.t()) :: boolean()
Whether msg is in our own chat (the "Message Yourself" chat): from_me and
addressed to our own account. The check a self-chat command channel needs — drive
an agent by messaging yourself.
Handles the LID/PN duality: the self chat may be addressed by our PN or our LID, so it
matches msg.to against both of our own identities (see Amarula.Connection.own_chat?/2).
On a single connection there's no feedback loop — a reply this connection sends to the
self chat is not delivered back to it (the sender's own device is excluded from
delivery), so you don't need to filter your own sends. Dedupe by msg_id only when
running two connections on the same account.
@spec pin_message(conn(), message_ref()) :: send_result()
Pin a message for everyone in the chat. ref is a %Amarula.Msg{} or {jid, msg_id}.
(Re)open the connection's websocket on an already-started connection — the
inverse of disconnect/1. Runs the handshake and logs in again with the
profile's stored credentials. Returns :ok | {:error, reason}.
Request a link-code (phone-number) pairing code for phone (E.164 digits;
any +, spaces, or dashes are stripped).
Call this during the QR window while unregistered — on the first
:connection_update carrying a qr. Returns {:ok, code} with an 8-char
code the user types into WhatsApp → Linked Devices → "Link with phone number".
Amarula finishes the handshake internally; the usual 515 restart then logs in
(watch for :pairing_success then connection: :open). The same code is also
delivered as a :pairing_code event.
opts: :custom_code — a fixed 8-char code to use instead of a random one.
@spec resolve_quoted(conn(), Amarula.Msg.t()) :: {:ok, Amarula.Msg.t()} | {:requested, String.t()} | {:error, term()}
Resolve the original message a reply quotes.
- If the reply carries the inline copy WhatsApp ships (
msg.quoted.message), return it immediately —{:ok, %Amarula.Msg{}}. - Otherwise ask the server to re-deliver the original —
{:requested, id}; it re-arrives async via:messages_upsert.
{:error, :not_a_reply} if msg doesn't quote anything.
Amarula does not keep an inbound-message store — delivery ends at
:messages_upsert(the message, its mentions, and the inline quote are all there). If you want to resolve a quote from your own history, look it up in whatever store you keep and skip this; this function only handles the inline copy and the server round-trip.
@spec send_album(conn(), jid(), [{:image | :video, binary(), keyword()}]) :: {:ok, String.t()} | {:error, term()}
Send an album (grouped media) to jid. items is a list of
{type, data, opts} (same shape as send_media/5), where type is :image
or :video. Sends the album parent first, then each item referencing it.
Returns {:ok, parent_msg_id} once the parent and all items are sent, or
{:error, {:album_item, index, reason}} if an item fails (the parent and
earlier items have already been sent).
WhatsApp expects ≥2 items, all images/videos.
Send a typing indicator to jid: :composing, :recording, or :paused.
@spec send_contact(conn(), jid(), String.t(), String.t()) :: send_result()
Send a contact (display_name + vCard string) to jid.
Send multiple contacts to jid: pairs is [{display_name, vcard}, ...].
@spec send_edit(conn(), message_ref(), String.t()) :: send_result()
Edit a message we sent, replacing its text. ref is a %Amarula.Msg{} or a
{jid, msg_id} tuple.
@spec send_event(conn(), jid(), String.t(), keyword()) :: send_result()
Send an event to jid (a group or 1:1). name is the title. opts:
:description, :location ({lat, lng} or [lat:, lng:, name:, address:]),
:join_link, :start_time / :end_time (unix seconds), :extra_guests_allowed.
Responding to an event (RSVP) is not yet supported — the response is an encrypted
EncEventResponseMessage, a separate crypto seam (like poll votes).
Send a group-invite message to jid — a tap-to-join card for group_jid using
code (from Amarula.Group.invite_code/2). opts: :group_name, :caption,
:expiration (unix ms).
Send a location to jid. opts: :name, :address, :url, :is_live.
@spec send_media(conn(), jid(), media_type(), binary(), keyword()) :: send_result()
Send media of type (:image/:video/:audio/:document/:sticker).
data is the raw file bytes — not a path, not base64. Read the file
yourself first:
bytes = File.read!("photo.jpg")
Amarula.send_media(conn, jid, :image, bytes, caption: "hi")Amarula encrypts and uploads the bytes for you. opts may carry :mimetype
(auto-detected per type if omitted), :caption, :width, :height,
:seconds, :ptt (voice note), :file_name, :title, plus:
:quoted/:mentions— reply to / tag (seesend_text/4).:view_once— send as view-once (the recipient can open it once).:ptv— for:video, send as a round video note (PTV).
@spec send_poll(conn(), jid(), String.t(), [String.t(), ...], keyword()) :: {:ok, String.t(), binary()} | {:error, term()}
Send a poll to jid. Returns {:ok, msg_id, message_secret} — keep the
message_secret to tally incoming votes (Amarula.Protocol.Messages.Poll).
opts: :selectable (max picks, default 1), :announcement, :message_secret.
@spec send_poll_vote(conn(), message_ref(), binary(), [String.t()], keyword()) :: send_result()
Cast a vote on an existing poll. poll is a message_ref for the poll-creation
message (a %Amarula.Msg{} or {jid, msg_id} tuple); message_secret is the
poll's 32-byte secret (from send_poll/5, or the poll's messageContextInfo);
option_names are the chosen options. The vote is encrypted under the secret.
The poll's creator is taken from the ref (a %Amarula.Msg{}'s sender, or the
{jid, _} chat for a 1:1 poll). For a group poll referenced by tuple, pass the
creator explicitly with :creator in opts.
@spec send_reaction(conn(), message_ref(), String.t()) :: send_result()
React to a message with emoji (empty string removes the reaction). ref is a
%Amarula.Msg{} or a {jid, msg_id} tuple.
@spec send_revoke(conn(), message_ref()) :: send_result()
Delete a message for everyone (revoke). ref is a %Amarula.Msg{} or a
{jid, msg_id} tuple.
@spec send_text(conn(), jid(), String.t(), keyword()) :: send_result()
Send a 1:1/group text message to jid. opts:
:quoted— reply to an%Amarula.Msg{}(threads the quote).:mentions— list of jids/%Amarula.Address{}to tag (@mention).
Set your global presence: :available (online) or :unavailable. Needs a profile name.
Stop a connection entirely — the whole supervision tree — and release its profile so it can be started again (here or, with a cluster registry, on another node).
Unlike disconnect/1 (which only closes the websocket; the supervised tree stays
up and may reconnect), stop/1 takes the tree down and frees the profile slot.
Accepts a connection pid or a profile (resolved via the default registry).
Returns :ok | {:error, :not_found}.
Subscribe to a contact's presence updates.
@spec unkeep_message(conn(), message_ref()) :: send_result()
Undo a previous keep (let the message disappear again). ref is a %Amarula.Msg{} or {jid, msg_id}.
@spec unpin_message(conn(), message_ref()) :: send_result()
Unpin a previously pinned message. ref is a %Amarula.Msg{} or {jid, msg_id}.
A :via handle for profile — usable anywhere a conn() is accepted, so calls
route to whatever pid currently holds the profile (restart-safe). Assumes the
default registry; for a custom one, build it from the Conn via
Amarula.ProfileRegistry.via/2.
The live connection pid for profile, or nil. A restart-safe handle: the pid
changes if the connection restarts, but the profile resolves to the current one.
Assumes the default Amarula.ProfileRegistry. With a custom :registry config,
pass the Conn (or config) as the first arg: whereis(conn, profile).
@spec whereis(Amarula.Conn.t() | map(), profile()) :: pid() | nil
As whereis/1, but resolves through conn_or_config's :registry.
Destructively forget this connection's profile: unlink the companion on WhatsApp's side (the phone drops the device), wipe all local storage for it (creds, sessions, keys, mappings), then disconnect. After this the profile must be re-paired to use again.
For a non-destructive teardown that keeps the credentials, use disconnect/1
(websocket only) or stop/1 (the whole tree, freeing the profile slot).