I am trying to integrate my app with salesforce and I am using Rest API using Python. Following things I am implementing

1. Any user of Salesforce from any domain integrate with my app who is registered on my app.

2. Once user integrate app with salesforce I will get access token which I will use in Rest API call.

3. I want to create Apex trigger in salesforce on behalf of user which will call my app API.

I am stuck at point 3 because I am not finding documentation for creating Apex trigger using Salesforce Rest API.

Also I want to know what are the permission levels for Apex Trigger and Apex class ? For example:

1. If user is integrating salesforce with my app and he is sales person and  not administrator then still he can create trigger and classes?

2. If my app ask for salesforce credential and user enter credential of salesforce which is in production  then still my app create apex trigger and apex class on behalf of user?  

I am trying to integrate my app with salesforce and I am using Rest API using Python. Following things I am implementing

1. Any user of Salesforce from any domain integrate with my app who is registered on my app.

2. Once user integrate app with salesforce I will get access token which I will use in Rest API call.

3. I want to create Apex trigger in salesforce on behalf of user which will call my app API.

I am stuck at point 3 because I am not finding documentation for creating Apex trigger using Salesforce Rest API.

Also I want to know what are the permission levels for Apex Trigger and Apex class ? For example:

1. If user is integrating salesforce with my app and he is sales person and  not administrator then still he can create trigger and classes?

2. If my app ask for salesforce credential and user enter credential of salesforce which is in production  then still my app create apex trigger and apex class on behalf of user?