engsure

Model validation that humans can read

pronounced like "ensure"

Table of Contents

• How to Use
  • API Docs
  • Best Practices
  • Simple Example
• How to Contribute

How to Use

API Docs

TODO

Best Practices

How to get the most out of engsure

provide descriptive labels with aka as much as possible

This makes your error messages significantly more valuable, by having a human-readable name for the item being validated.

limit uses from engsure as much as possible

the API was designed with concise names, that way you can use fully-qualified names rather than bringing them directly into scope.

implement the engsure::Validate trait

This has 2 benefits:

1. it lets you separately define engsure functionality from the rest of your struct's functionality
2. by returning the engsure::Ctx<MyStruct>, you have more flexibility on what you can do after validating.
   • e.g. chain validation of other instances with and_then (see the main fn in Simple Example)

Simple Example

struct Person {
  pub first_name: String,
  pub last_name: String,
  pub phone_number: (i8, i8, i8),
  pub email: Option<String>
}

impl Person {
  pub fn name(&self) -> String {
    format!("{} {}", self.first_name, self.last_name)
  }
}

impl engsure::Validate for Person {
  use engsure::opt::{is_some};
  use engsure::tup::{is_phone_number};
  use engsure::txt::{is_email_address};

  pub fn validate(self) -> engsure::Ctx<Person> {
    engsure::that(self)
      .aka(self.name())
      .has(|p| p.phone_number)
      .that(is_phone_number)
      .and()
      .has(|p| p.email)
      .when(is_some)
      .that(is_email_address)
      .done()
  }
}

pub fn main() -> engsure::Result {
  let bob = Person {
    first_name: "Bob",
    last_name: "Builder",
    phone_number: (505, 555, 1234),
    email: Some("bob.t.builder@yeswecan.org")
  }
  
  let sally = Person {
    first_name: "Sally",
    last_name: "Jackson",
    phone_number: (602, 111, 2222),
    email: Some("forgot-dotcom@gmail")
  };

  // The following errors with:
  //   engsure::TextError { msg: "invalid email of 'forgot-dotcom@gmail' in 'Sally Jackson'", .. }
  bob.validate()
    .and_then(|_| sally.validate())
    .done()
}

How to Contribute

TODO