Do I get an error when I send a message with a user ID that blocks the LINE Official Account?
If you send a message specifying a user who has blocked the LINE Official Account or a user who deleted their account, no error will occur and status code 200 will be returned as a response.
In this case, no message will be sent to the user.
Do I get an error when I send a message with a user ID that doesn't exist?
If a message is sent to a user ID that doesn't exist, this error will be returned with status code 400.
"message": "Failed to send messages"
Note that the user ID is a value issued for each provider. If you send a message with a user ID issued by another provider, it will be treated as if you sent the message to a user ID that doesn't exist.
How many full-width characters, emojis, line breaks, and so on, are counted in the text character count?
Characters in a text are counted in UTF-16 code units (16-bit). Characters expressed in multiple code units, such as some kanji characters and Unicode emojis, are counted as multiple characters instead of one character.
Also, unlike Unicode emojis, LINE emojis provided by LINE are internally converted to the alternative text (e.g., (love)), so they're counted by the number of characters in the alternative text.
Examples of counting the number of characters in UTF-16 code units are as follows:
UTF-16 encoded value
Number of code units
Number of characters
D83D DC4B D83C DFFB
If I send a message to a user who doesn't receive the message, is it still counted as one message?
If you specify a user who doesn't actually receive the message, such as a user ID that blocked the LINE Official Account or a user ID that doesn't exist, the message won't be counted even if you call the API for sending the message.
If I send a push message with multiple message objects (for example, 4) in a single request to a group chat or multi-person chat with multiple people (for example, 5 people), how many messages will be counted?
The number of messages is counted by the number of people to whom the message was sent. In this example, if there are five people in the group chat or multi-person chat where you sent the message, the number of messages counted is five. The number of message objects specified in a single request doesn't affect the number of messages sent.