simpletemplate

Template engine written entirely in rust.

usage

// main.rs
use simpletemplate::render;
use serde_json::{json};

fn main() {
    let data = json!({
        "name": ["Bob Belcher"],
    });
    let content = "{{ name }}";
    let res = render(content, data);
    println!("{}", res); //returns Bob Belcher
}

template usage

For variables, use {{ variable_name }}.

For array indexing, use {{ array_name[index] }}.

To iterate over an array:

{{ for loop_variable in loop_iterable }} 
    loop_body 
{{ endfor }}

To access the index:

{{ for loop_variable in loop_iterable }} 
    {{ index }}
{{ endfor }}

If statements: if_body is rendered if condition is not null, false, or "false".

{{ if condition }} 
    if_body 
{{ else }} 
    else_body 
{{ endif }} 

View src/main.rs to see how to render from an HTML file.

lib.rs:

Render html templates.

Examples

// variables
let data = json!({ "foo": "bar" });
let template = r"{{ foo }}";
let expected = "bar";
assert_eq!(render(template, data), expected);

// logic statements
let data = json!({ "foo": "bar" });
let template = r"{{ if foo }}{{ foo }}{{ else }}foo is not set{{ endif }}";
let expected = "bar";
assert_eq!(render(template, data), expected);

let data = json!({ "foo": null });
let template = r"{{ if foo }}{{ foo }}{{ else }}foo is not set{{ endif }}";
let expected = "foo is not set";
assert_eq!(render(template, data), expected);

// for loop
let data = json!({ "items": ["a", "b", "c"] });
let template = r"{{ for item in items }}{{ item }}{{ endfor }}";
let expected = "abc";
assert_eq!(render(template, data), expected);

let data = json!({ "items": [] });
let template = r"{{ for item in items }}{{ item }}{{ endfor }}";
let expected = "";
assert_eq!(render(template, data), expected);

// accessing by index
let data = json!({ "items": ["a", "b", "c"] });
let template = r"{{ items[0] }}";
let expected = "a";
assert_eq!(render(template, data), expected);

let data = json!({ "items": ["a", "b", "c"] });
let template = r"{{ items[1] }}";
let expected = "b";
assert_eq!(render(template, data), expected);

let data = json!({ "items": ["a", "b", "c"] });
let template = r"{{ items[2] }}";
let expected = "c";
assert_eq!(render(template, data), expected);

// combining logic
let data = json!({
"foo": "bar",
"items": ["a", "b", "c"],
"show_items": true,
"show_foo": false,
});
let template = r"{{ if show_items }}{{ for item in items }}{{ item }}{{ endfor }}{{ endif }}{{ if show_foo }}{{ foo }}{{ endif }}";
let expected = "abc";
assert_eq!(render(template, data), expected);

let data = json!({
"foo": "bar",
"items": ["a", "b", "c"],
"show_items": true,
"show_foo": false,
});
let template = r"{{ if show_items }}{{ for item in items }}{{ item }}{{ endfor }}{{ endif }}{{ if show_foo }}{{ foo }}{{ else }}foo is not set{{ endif }}";
let expected = "abcfoo is not set";
assert_eq!(render(template, data), expected);

// blank template
let data = json!({});
let template = "";
let expected = "";
assert_eq!(render(template, data), expected);

// invalid variable
let data = json!({ "foo": "bar" });
let template = "{{ baz }}";
let expected = "null";
assert_eq!(render(template, data), expected);

// invalid index
let data = json!({ "items": ["a", "b", "c"] });
let template = "{{ items[5] }}";
let expected = "null";
assert_eq!(render(template, data), expected);

// invalid statement
let data = json!({});
let template = "{{ if foo }}{{ endif }}";
let expected = "";
assert_eq!(render(template, data), expected);