Send message with Google Business Messages using access token - node.js

Question

Currently I can send a message with Google Business Messages API from an agent to a user from NodeJS code.
const bmApi = new businessmessages.businessmessages_v1.Businessmessages({});
This requires an auth client for a given service account key/secret.
const auth = new GoogleAuth({
keyFilename: '/home/my-keyfile.json',
scopes: 'https://www.googleapis.com/auth/businessmessages',
});
const authClient = await auth.getClient();
// and logic to send message
However the key/secret is hard-coded at the moment.
But at this point in the flow I have the access token.
And want to use that instead of the .json file.
But it will not accept the access token.
Another approach is to directly call the REST interface.
https://developers.google.com/business-communications/business-messages/guides/how-to/message/send
curl -X POST https://businessmessages.googleapis.com/v1/conversations/__CONVERSATION_ID__/messages \
-H "Content-Type: application/json" \
-H "User-Agent: curl/business-messages" \
-H "$(oauth2l header --json ./service_account_key.json businessmessages)" \
-d "{
'messageId': '$(uuidgen)',
'text': 'Hello world!',
'representative': {
'avatarImage': 'https://developers.google.com/identity/images/g-logo.png',
'displayName': 'Chatbot',
'representativeType': 'BOT'
}
}"
Added a header with token.
access_token: <access-token>
But again no joy.
{
"error": {
"code": 401,
"message": "Request had invalid authentication credentials. Expected OAuth 2 access token, login cookie or other valid authentication credential. See https://developers.google.com/identity/sign-in/web/devconsole-project.",
"status": "UNAUTHENTICATED"
}
}
I know this should work as we do it for calls to Google Play Store:
try {
let response = await this.httpClient.post({
url: `${process.env.PLAYSTORE_URL}/${packageName}/reviews/${reviewId}:reply`,
body : {
"replyText" : replyText
},
query: {
access_token: access_token <----
}
});
Any help would be much appreciated.

Answer 1

i think you need to use the variable that match the current CONVERSATION_ID in the url path, with the currently one of each agent message received.
Example:
curl -X POST https://businessmessages.googleapis.com/v1/conversations/$(uuidgen)/messages \
-H "Content-Type: application/json" \
-H "User-Agent: curl/business-messages" \
-H "$(oauth2l header --json ./service_account_key.json businessmessages)" \
-d "{
'messageId': '$(uuidgen)',
'text': 'Hello world!',
'representative': {
'avatarImage': 'https://developers.google.com/identity/images/g-logo.png',
'displayName': 'Chatbot',
'representativeType': 'BOT'
}
}"