NAME LINE::Bot::API - SDK of the LINE Messaging API for Perl Maintenance Mode As of May 13, 2024, the project line-bot-sdk-perl project will enter maintenance mode. During this period, we will continue to provide critical bug fixes and security updates; however, new features will not be added. We encourage the community to submit patches and improvements, which we will gladly review and merge as appropriate. Archiving On December 2, 2024, the repository line-bot-sdk-perl will be archived. This means the codebase will become read-only. While the repository will still be available for cloning and viewing, no further contributions or changes will be accepted. We recommend users and developers fork the repository if they wish to continue development independently. We appreciate the support and contributions from our community throughout the project's lifecycle. Thank you for being a part of our journey. SYNOPSIS # in the synopsis.psgi use strict; use warnings; use LINE::Bot::API; use LINE::Bot::API::Builder::SendMessage; use Plack::Request; my $bot = LINE::Bot::API->new( channel_secret => $channel_secret, channel_access_token => $channel_access_token, ); sub { my $req = Plack::Request->new(shift); unless ($req->method eq 'POST' && $req->path eq '/callback') { return [200, [], ['Not Found']]; } unless ($bot->validate_signature($req->content, $req->header('X-Line-Signature'))) { return [200, [], ['failed to validate signature']]; } my $events = $bot->parse_events_from_json($req->content); for my $event (@{ $events }) { next unless $event->is_message_event && $event->is_text_message; my $messages = LINE::Bot::API::Builder::SendMessage->new; $messages->add_text( text => $event->text ); $bot->reply_message($event->reply_token, $messages->build); } return [200, [], ["OK"]]; }; DESCRIPTION LINE::Bot::API is a client library which lets you easily start using the LINE Messaging API. You can create a bot which runs on the LINE app by registering for a LINE Messaging API account. You can create a Messaging API account from the LINE Business Center . You can find the Channel secret and Channel access token on the Basic information page on the Channel Console which you can access from the LINE Business Center . Use this documentation and the LINE Developers documentation to get you started developing your own bot! METHODS new(%args) Create a new LINE::Bot::API instance. my $bot = LINE::Bot::API->new( channel_secret => $channel_secret, channel_access_token => $channel_access_token, ); reply_message($reply_token, [ $message, ... ] ) Send reply messages to a user, room or group. my $messages = LINE::Bot::API::Builder::SendMessage->new; $messages->add_text( text => 'Example reply text' ); my $ret = $bot->reply_message($reply_token, $messages->build); unless ($ret->is_success) { # error warn $ret->message; for my $detail (@{ $ret->details // []}) { warn " detail: " . $detail->{message}; } } You can get a reply_token from a webhook event object . See the documentation for the parse_events_from_json($json) method. See also the API reference of this method: https://developers.line.biz/en/reference/messaging-api/#send-reply-message push_message( $user_id|$room_id|$group_id, $message, $options) Send push messages to a user, room or group. my $messages = LINE::Bot::API::Builder::SendMessage->new; $messages->add_text( text => 'Example push text' ); $bot->push_message($user_id, $messages->build); You can get a user_id, room_id or group_id from a webhook event object See the documentation for the parse_events_from_json($json) method. The last parameter $options is an HashRef with a list of key-values pairs to fine-tune the behaviour of this message. At the moment, the only defined configurable option is "retry_key", which requires an UUID string for its value. See the section "Handling Retries" for the meaning of this particular option. For mor detail, read the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#send-push-message multicast( $user_id, $message, $options ) Send push messages to multiple users. my $messages = LINE::Bot::API::Builder::SendMessage->new; $messages->add_text( text => 'Example push text' ); $bot->multicast([ $user_id ], $messages->build); You can get a user_id from a webhook event object . See the documentation for the parse_events_from_json($json) method. The last parameter $options is an HashRef with a list of key-values pairs to fine-tune the behaviour of this message. At the moment, the only defined configurable option is "retry_key", which requires an UUID string for its value. See the section "Handling Retries" for the meaning of this particular option. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#send-multicast-messages broadcast($message, $options) Sends push messages to multiple users at any time. my $messages = LINE::Bot::API::Builder::SendMessage->new; $messages->add_text( text => 'Example push text' ); $bot->broadcast($messages->build); The last parameter $options is an HashRef with a list of key-values pairs to fine-tune the behaviour of this message. At the moment, the only defined configurable option is "retry_key", which requires an UUID string for its value. See the section "Handling Retries" for the meaning of this particular option. See also the LINE Developers API reference of thi smethod: https://developers.line.biz/en/reference/messaging-api/#send-broadcast-message validate_signature($json, $signature) my $req = Plack::Request->new( ... ); unless ($bot->validate_signature($req->content, $req->header('X-Line-Signature'))) { die 'failed to signature validation'; } parse_events_from_json($json) Parse webhook event objects and build LINE::Bot::API::Event instances. my $req = Plack::Request->new( ... ); my $events = $bot->parse_events_from_json($req->content); for my $event (@{ $events }) { unless ($event->is_unfollow_event && $event->is_leave_event) { # Get a reply_token my $reply_token = $event->reply_token; } if ($event->is_user_event) { # Get a user_id my $user_id = $event->user_id; } if ($event->is_room_event) { # Get a room_id my $room_id = $event->room_id; } if ($event->is_group_event) { # Get a group_id my $group_id = $event->group_id; } if ($event->is_message_event) { # Get a message id my $message_id = $event->message_id; } } leave_room($room_id) Bot leaves a room. $bot->leave_room($room_id); You can get a room_id by a Webhook Event Object . And see also parse_events_from_json($json) method's document. leave_group($group_id) Bot leaves a group. $bot->leave_group($group_id); You can get a group_id from a webhook event object . See the documentation for the parse_events_from_json($json) method. get_message_content($message_id) Get the original file which was sent by user. my $ret = $bot->get_message_content($message_id); if ($ret->is_success) { my $filename = $ret->fh->filename; open my $fh, '<', $file or die "$!: $file"; ... } You can get a message_id from a webhook event object . See the documentation for the parse_events_from_json($json) method. You can also see the online API reference documentation. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-content get_target_limit_for_additional_messages Gets the target limit for additional messages in the current month. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-quota get_number_of_messages_sent_this_month Gets the number of messages sent in the current month. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-consumption get_number_of_message_deliveries({ date => ... }) Get the number of messages sent from LINE official account on a specified day. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-number-of-delivery-messages The argument is a HashRef with one pair of mandatory key-values; { date => "20191231" } The formate of date is "yyyyMMdd", that is, year in 4 digits, month in 2 digits, and date-of-month in 2 digits. The return value $res is a response object with the following read-only accessors (see the API documentation for the meaning of each.) $res->status(); #=> Str $res->broadcast(); #=> Num $res->targeting(); #=> Num Notice that the "status" does not mean HTTP status. To inspect actual HTTP status, invoke $res-http_status()>. get_profile($user_id) Get user profile information. my $ret = $bot->get_profile($user_id); if ($ret->is_success) { say $ret->display_name; say $ret->user_id; say $ret->picture_url; say $ret->status_message; say $ret->language; } See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-profile get_friend_demographics Retrieves the demographic attributes for a LINE Official Account's friends. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-demographic get_group_member_profile($group_id, $user_id) Get group user profile information. my $ret = $bot->get_group_member_profile($group_id, $user_id); if ($ret->is_success) { say $ret->display_name; say $ret->user_id; say $ret->picture_url; } See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-group-member-profile get_member_in_room_count($room_id) Gets the count of members in a room. You can get the member in room count even if the user hasn't added the LINE Official Account as a friend or has blocked the LINE Official Account. my $ret = $bot->get_member_in_room_count($room_id); if ($ret->is_success) { say $ret->count; } See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-members-room-count get_member_in_group_count($group_id) Gets the count of members in a group. You can get the member in group count even if the user hasn't added the LINE Official Account as a friend or has blocked the LINE Official Account. my $ret = $bot->get_member_in_group_count($group_id); if ($ret->is_success) { say $ret->count; } See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-members-group-count get_group_summary($group_id) Gets the group ID, group name, and group icon URL of a group where the LINE Official Account is a member. my $ret = $bot->get_group_summary($group_id); if ($ret->is_success) { say $ret->group_id; say $ret->group_name; say $ret->picture_url; } See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-group-summary get_room_member_profile($room_id, $user_id) Get room user profile information. A room is like a group without a group name. The response is similar to get_group_member_profile. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-room-member-profile get_number_of_sent_reply_messages($date) Gets the number of messages sent with the /bot/message/reply endpoint. The number of messages retrieved by this operation does not include the number of messages sent from LINE@ Manager. The $date parameter is "yyyyMMdd" format. get_number_of_sent_push_messages($date) Gets the number of messages sent with the /bot/message/push endpoint. The number of messages retrieved by this operation does not include the number of messages sent from LINE@ Manager. date Date the messages were sent Format: yyyyMMdd (Example: 20191231) Timezone: UTC+9 get_number_of_sent_multicast_messages($date) Gets the number of messages sent with the /bot/message/multicast endpoint. The number of messages retrieved by this operation does not include the number of messages sent from LINE@ Manager. date Date the messages were sent Format: yyyyMMdd (Example: 20191231) Timezone: UTC+9 get_number_of_send_broadcast_messages($date) Gets the number of messages sent with the /bot/message/broadcast endpoint. The number of messages retrieved by this operation does not include the number of messages sent from LINE Official Account Manager. date Date the messages were sent Format: yyyyMMdd (Example: 20191231) Timezone: UTC+9 create_rich_menu( $rich_menu_object ) This method corresponds to the API of Creating rich menu One argument is needed: $rich_menu_object, which is a plain HashRef representing rich menu object get_rich_menu( $rich_menu_id ) This method corresponds to the API of Get rich menu One argument is needed: $rich_menu_id -- which correspond to the richMenuId property of the object returned by create_rich_menu method. delete_rich_menu( $rich_menu_id ) This method corresponds to the API of Delete rich menu One argument is needed: $rich_menu_id -- which correspond to the richMenuId property of the object returned by create_rich_menu method. The return value is an empty RichMenu object -- only status code matters. Upon successful deletion, status code 200 is returned. get_rich_menu_list This method corresponds to the API of Get rich menu list No arguments are needed. set_default_rich_menu( $rich_menu_id ) This method corresponds to the API of Set default rich menu One argument is needed: $rich_menu_id -- which correspond to the richMenuId property of the object returned by create_rich_menu method. get_default_rich_menu_id This method corresponds to the API of Get default rich menu ID No arguments are needed. The return value is a RichMenu object with only one property: richMenuId. cancel_default_rich_menu This method corresponds to the API of Cancel default rich menu ID link_rich_menu_to_user( $user_id, $rich_menu_id ) This method corresponds to the API of Link rich menu to user Both of $user_id and $rich_menu_id are required. link_rich_menu_to_multiple_users( $user_ids, $rich_menu_id ) This method corresponds to the API of Link rich menu to multiple users Both of $user_ids and $rich_menu_id are required. $user_ids should be an ArrayRef of user ids, while $rich_menu_id should be a simple scalar. get_rich_menu_id_of_user( $user_id ) This method corresponds to the API of Get rich menu ID of user The argument $user_id is mandatory. The return value is a RichMenu object with only one property: richMenuId. unlink_rich_menu_from_user( $user_id ) This method corresponds to the API of Unlink rich menu from user The argument $user_id is mandatory. The return value is an empty object. unlink_rich_menu_from_multiple_users( $user_ids ) This method corresponds to the API of Unlink rich menu from multiple users The mandatory argument $user_ids is an ArrayRef of user ids. The return value is an empty object. validate_rich_menu_object( $rich_menu_object ) This method corresponds to the API of Validate rich menu object One argument is needed: $rich_menu_object, which is a plain HashRef representing rich menu object issue_channel_access_token({ client_id => '...', client_secret => '...' }) This method corresponds to the API of: Issue Channel access token The argument is a HashRef with two pairs of mandatory key-values: { client_id => "...", client_secret => "...", } Both pieces of information can be accquired from the channel console. When a 200 OK HTTP response is returned, a new token is issued. In this case, you may want to store the values in "access_token", "expires_in", and "token_type" attributes of the response object for future use. Otherwise, you my examine the "error" attribute and "error_description" attribute for more information about the error. issue_channel_access_token_v2_1({ jwt => '...' }) This method corresponds to the API of: Issue Channel access token v2.1 The argument is a HashRef with a pair of mandatory key-values: { jwt => "...", } This method lets you use JWT assertion for authentication. When a 200 OK HTTP response is returned, a new token is issued. In this case, you may want to store the values in "access_token", "expires_in", "token_type" and "key_id" attributes of the response object for future use. Otherwise, you may examine the "error" attribute and "error_description" attribute for more information about the error. get_valid_channel_access_token_v2_1({ jwt => '...' }) This method corresponds to the API of: Get all valid channel access token key IDs v2.1 The argument is a HashRef with a pair of mandatory key-values: { jwt => "...", } This method is for getting all valid channel access token key IDs. When a 200 OK HTTP response is returned, a new token is issued. In this case, you may want to store the values in "key_ids" attributes of the response object for future use. Otherwise, you may examine the "error" attribute and "error_description" attribute for more information about the error. revoke_channel_access_token({ access_token => "..." }) This method corresponds to the API of: Revoke channel access token The argument is a HashRef with one pair of mandatory key-values; { access_token => "..." } Upon successful revocation, a 200 OK HTTP response is returned. Otherwise, you my examine the "error" attribute and "error_description" attribute for more information about the error. get_number_of_followers({ date => "..." }) This method corresponds to the API of: Get number of followers The argument is a HashRef with one pair of mandatory key-values; { date => "20191231" } The formate of date is "yyyyMMdd", that is, year in 4 digits, month in 2 digits, and date-of-month in 2 digits. Upon successful invocation, a 200 OK HTTP response is returned. Otherwise, you my examine the "error" attribute and "error_description" attribute for more information about the error. The return value $res is a response object with the following read-only accessors (see the API documentation for the meaning of each.) $res->status(); #=> Str, one of: "ready", "unready", "out_of_service" $res->followers(); #=> Num $res->targetedReaches(); #=> Num $res->blocks(); #=> Num Notice that the "status" does not mean HTTP status. To inspect actual HTTP status, invoke $res-http_status()>. get_user_interaction_statistics({ requestId => "..." }) Returns statistics about how users interact with narrowcast messages or broadcast messages sent from your LINE Official Account. See also the LINE Developers API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-message-event set_webhook_url({ 'endpoint' => "https://example.com/webhook" }) Sets the webhook endpoint to te given endpoint, which should be an URL string. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#set-webhook-endpoint-url get_webhook_endpoint_information() Return the information about webhook endpoint as an response object with following accessors: $res = $api->get_webhook_endpoint_information(); $res->endpoint(); # URL as a string $res->active(); # true or false See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-webhook-endpoint-information test_webhook_endpoint({ 'endpoint' => "https://example.com/webhook" }) Checks if the configured webhook endpoint can receive a test webhook event. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-webhook-endpoint-information validate_reply_message_objects([ $message, ... ] ) Validates that an array of message objects is valid as a value for the messages property of the request body for the Send reply message endpoint. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#validate-message-objects-of-reply-message validate_push_message_objects([ $message, ... ] ) Validates that an array of message objects is valid as a value for the messages property of the request body for the Send push message endpoint. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#validate-message-objects-of-push-message validate_multicast_message_objects([ $message, ... ] ) Validates that an array of message objects is valid as a value for the messages property of the request body for the Send multicast message endpoint. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#validate-message-objects-of-multicast-message validate_narrowcast_message_objects([ $message, ... ] ) Validates that an array of message objects is valid as a value for the messages property of the request body for the Send narrowcast message endpoint. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#validate-message-objects-of-narrowcast-message validate_broadcast_message_objects([ $message, ... ] ) Validates that an array of message objects is valid as a value for the messages property of the request body for the Send broadcast message endpoint. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#validate-message-objects-of-broadcast-message get_followers({ 'limit' => 100, 'start' => "..." }) Gets the list of User IDs of users who have added LINE Official Account as a friend. See also the LINE Developer API reference of this method: https://developers.line.biz/en/reference/messaging-api/#get-follower-ids How to build a send message object See the LINE Developers API reference about Message objects When the LINE::Bot::API::Builder::SendMessage class is used, it is possible easily to build a send message object. That class supports a fluent interface. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_text( text => 'Closing the distance', )->add_image( image_url => 'http://example.com/image.jpg', preview_url => 'http://example.com/image_preview.jpg', ); $bot->reply_message($reply_token, $messages->build); Text type Build a text type object. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_text( text => 'Closing the distance', ); $bot->reply_message($reply_token, $messages->build); Build a text message with emojis inside: my $message = LINE::Bot::API::Builder::SendMessage->new(); $message->add_text( text => '$ LINE Emoji $', emojis => [ +{ "index" => 0, "productId" => "5ac1bfd5040ab15980c9b435", "emojiId" => "001" }, +{ "index" => 13, "productId" => "5ac1bfd5040ab15980c9b435", "emojiId" => "002" } ] ); Since 2020/04/16, text messages may contain LINE emojis. They are identified by (productId, emojiId). For more details about possible values as well as how to use these emojis, please read: https://developers.line.biz/en/reference/messaging-api/#text-message first. Image type Build an image type object. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_image( image_url => 'http://example.com/image.jpg', preview_url => 'http://example.com/image_preview.jpg', ); $bot->reply_message($reply_token, $messages->build); Video type Build a video type object. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_video( video_url => 'http://example.com/video.mp4', preview_url => 'http://example.com/video_preview.jpg', ); $bot->reply_message($reply_token, $messages->build); Audio type Build an audio type object. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_audio( audio_url => 'http://example.com/image.m4a', duration => 3601_000, # msec ); $bot->reply_message($reply_token, $messages->build); Location type Build a location type object. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_location( title => 'LINE Corporation.', address => 'Hikarie Shibuya-ku Tokyo 151-0002', latitude => 35.6591, longitude => 139.7040, ); $bot->reply_message($reply_token, $messages->build); Sticker type Build a sticker type object. my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_sticker( package_id => '1', sticker_id => '2', ); $bot->reply_message($reply_token, $messages->build); Imagemap type To build a message of imagemap type, you may use a helper module. my $imagemap = LINE::Bot::API::Builder::ImagemapMessage->new( base_url => 'https://example.com/bot/images/rm001', alt_text => 'this is an imagemap', base_width => 1040, base_height => 1040, )->add_uri_action( uri => 'http://example.com/', area_x => 0, area_y => 0, area_width => 1040, area_height => 520, )->add_message_action( text => 'message', area_x => 0, area_y => 520, area_width => 1040, area_height => 520, ); my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_imagemap($imagemap->build); $bot->reply_message($reply_token, $messages->build); An Imagemap message can contain a video area inside. Here is an example of one withe upper half being a video overlay: my $imagemap_message = LINE::Bot::API::Builder::ImagemapMessage->new( base_url => 'https://example.com/bot/images/rm001', alt_text => 'this is an imagemap', base_width => 1040, base_height => 1040, video => { originalContentUrl => "https://example.com/video.mp4", previewImageUrl => "https://example.com/video_preview.jpg", area => { x => 0, y => 0, width => 1040, height => 585 } } )->build; For more detail about Imagemap message, see: https://developers.line.biz/en/reference/messaging-api/#imagemap-message Template type Build a template type object. You can use a helper module for the template type. Buttons type my $buttons = LINE::Bot::API::Builder::TemplateMessage->new_buttons( alt_text => 'this is a buttons template', image_url => 'https://example.com/bot/images/image.jpg', title => 'buttons', text => 'description', )->add_postback_action( label => 'postback', data => 'postback data', text => 'postback message', )->add_message_action( label => 'message', text => 'message', )->add_uri_action( label => 'uri', uri => 'http://example.com/', )->add_message_action( label => 'message2', text => 'message2', ); my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_template($buttons->build); $bot->reply_message($reply_token, $messages->build); Confirm type my $confirm = LINE::Bot::API::Builder::TemplateMessage->new_confirm( alt_text => 'this is a confirm template', text => 'confirm', )->add_postback_action( label => 'postback', data => 'postback data', text => 'postback message', )->add_message_action( label => 'message', text => 'message', )->add_uri_action( label => 'uri', uri => 'http://example.com/', ); my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_template($confirm->build); $bot->reply_message($reply_token, $messages->build); Carousel type my $carousel = LINE::Bot::API::Builder::TemplateMessage->new_carousel( alt_text => 'this is a carousel template', ); for my $i (1..5) { my $column = LINE::Bot::API::Builder::TemplateMessage::Column->new( image_url => 'https://example.com/bot/images/item.jpg', title => "carousel $i", text => "description $i", )->add_postback_action( label => 'postback', data => 'postback data', text => 'postback message', )->add_message_action( label => 'message', text => 'message', )->add_uri_action( label => 'uri', uri => 'http://example.com/', ); $carousel->add_column($column->build); } my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_template($carousel->build); $bot->reply_message($reply_token, $messages->build); Image Carousel type my $carousel = LINE::Bot::API::Builder::TemplateMessage->new_image_carousel( alt_text => 'this is a image carousel template', ); my $column1 = LINE::Bot::API::Builder::TemplateMessage::ImageColumn->new( image_url => 'https://example.com/bot/images/item1.jpg', )->add_postback_action( label => 'postback', data => 'postback data', text => 'postback message', ); $carousel->add_column($column1->build); my $column2 = LINE::Bot::API::Builder::TemplateMessage::ImageColumn->new( image_url => 'https://example.com/bot/images/item2.jpg', )->add_message_action( label => 'message', text => 'message', ); $carousel->add_column($column2->build); my $column3 = LINE::Bot::API::Builder::TemplateMessage::ImageColumn->new( image_url => 'https://example.com/bot/images/item3.jpg', )->add_uri_action( label => 'uri', uri => 'http://example.com/', ); $carousel->add_column($column3->build); my $messages = LINE::Bot::API::Builder::SendMessage->new( )->add_template($carousel->build); $bot->reply_message($reply_token, $messages->build); Handling Retries For many methods that sends outgoing messages, the last parameter $options is a HashRef with certain key-value pairs. At the moment, the key 'retry_key' is recognized. It shall be provided to retry without causing duplicates. For example, here's a short snippet to attemp to retry a push_message without resending duplicate messages: my $k = create_UUID_as_string(); my $res = $bot->push_message( $user_id, $message, { 'retry_key' => $k } ); unless ($res->is_success) { while ($res->http_status ne '409') { sleep(60); $res = $bot->push_message( $user_id, $message, { 'retry_key' => $k } ); } } The value of 'retry_key' must be an UUID string. The example above uses the create_UUID_as_string() function provided by UUID::Tiny and should just work. The value of 'retry_key' is essentially value of an HTTP header name 'X-Line-Retry-Key'. Read more about retrying a failed push_message at: https://developers.line.biz/en/reference/messaging-api/#retry-api-request AUTHORS LINE Corporation. COPYRIGHT Copyright 2016-2021 LICENSE This Software Development Kit is licensed under The Artistic License 2.0. You may obtain a copy of the License at https://opensource.org/licenses/Artistic-2.0 SEE ALSO LINE::Bot::API::Event, https://developers.line.biz/, https://at.line.me/