TryFrom is a Rust standard-library trait for conversions that may fail. It returns Result<Self, Error>, allowing conversion faults to use the application's unified error type. section 6.2.1
In an Actix Web handler, incoming web::Json<CreateCourse> data can be converted into the regular CreateCourse struct. Implement try_from, declare EzyTutorError as the associated Error type, and return Ok for successful construction or an application error when processing fails. section 6.2.1
Converting an incoming course payload
use std::convert::TryFrom; impl TryFrom<web::Json<CreateCourse>> for CreateCourse { type Error = EzyTutorError; fn try_from(new_course: web::Json<CreateCourse>) -> Result<Self, Self::Error> { Ok(CreateCourse { tutor_id: new_course.tutor_id, course_name: new_course.course_name.clone(), course_description: new_course.course_description.clone(), course_format: new_course.course_format.clone(), course_structure: new_course.course_structure.clone(), course_level: new_course.course_level.clone(), course_duration: new_course.course_duration.clone(), course_language: new_course.course_language.clone(), course_price: new_course.course_price, }) } } This example has no anticipated failure conditions, so From is sufficient in practice; TryFrom demonstrates the fallible form. section 6.2.1
