i solved it, in embed configuration api is a example how the variable must be set.
see
Configuration | n8n Docs
{
"asanaOAuth2Api": {
"clientId": "<id>",
"clientSecret": "<secret>"
},
"githubOAuth2Api": {
"clientId": "<id>",
"clientSecret": "<secret>"
}
}
this is my line in a docker compose file to set the variable.
- CREDENTIALS_OVERWRITE_DATA={"oAuth2Api":{"clientId":"<someclientid>","clientSecret":"<someclientsecret>"},"httpBasicAuth":{"user":"<someusername>","password":"<somepassword>"}}