Template RS CLI

A command-line interface for managing and executing Rust code templates using the rust_templates library.

Installation

cargo install template_rs_cli

Or build from source:

git clone https://github.com/tristanpoland/template_rs_cli
cd template-cli
cargo install --path .

Requirements

• Rust 1.70 or higher
• rust-script (for template execution)

For template execution, ensure rust-script is installed:

cargo install rust-script

Commands

Creating Templates

Create a new template file with inline content:

template_rs_cli new -o hello.template_rs -c 'fn main() { println!("@[message]@"); }'

Create a template from an existing file:

template_rs_cli new -o output.template_rs -f input.rs

Rendering Templates

Render a template with placeholder values:

template_rs_cli render \
    -t hello.template_rs \
    -v message="Hello, World!" \
    -o hello.rs

Multiple values can be provided:

template_rs_cli render \
    -t struct.template_rs \
    -v struct_name=User \
    -v fields="name: String, age: u32" \
    -o user.rs

Executing Templates

Execute a template with rust-script:

template_rs_cli execute \
    -t math.template_rs \
    -v number_type=f64 \
    -v value=42.0 \
    -d "num=0.4"

Add multiple dependencies:

template_rs_cli execute \
    -t web.template_rs \
    -v url="https://api.example.com" \
    -d "reqwest=0.11" \
    -d "tokio=1.0" \
    -d "serde_json=1.0"

Assembling Templates

Combine multiple templates with shared values:

template_rs_cli assemble \
    -t header.template_rs \
    -t implementation.template_rs \
    -t tests.template_rs \
    -v module_name=calculator \
    -o combined.rs

Template Format

Templates use @[placeholder_name]@ syntax for placeholders:

// Example template
fn @[function_name]@() -> @[return_type]@ {
    let value = @[value]@;
    println!("@[message]@: {}", value);
    value
}

Value Formatting

Values are provided using key=value pairs:

• Basic values: name=value
• Strings with spaces: message="Hello World"
• Multiple lines: Use \n for newlines
• Rust code: Escape special characters as needed

Dependencies

Dependencies for template execution use name=version format:

-d "serde=1.0"
-d "tokio=1.0"

Error Handling

The CLI provides clear error messages for common issues:

• Missing placeholder values
• Invalid template syntax
• File system errors
• Execution errors
• Invalid dependency specifications

Examples

Basic Hello World

# Create template
template_rs_cli new -o hello.template_rs -c '
fn main() {
    println!("@[greeting]@ @[name]@!");
}
'

# Render template
template_rs_cli render \
    -t hello.template_rs \
    -v greeting=Hello \
    -v name=World \
    -o hello.rs

# Execute template
template_rs_cli execute \
    -t hello.template_rs \
    -v greeting=Hello \
    -v name=World

Data Structure Template

# Create a struct template
template_rs_cli new -o struct.template_rs -c '
#[derive(Debug)]
struct @[struct_name]@ {
    @[fields]@
}

fn main() {
    let instance = @[struct_name]@ {
        @[field_values]@
    };
    println!("{:?}", instance);
}
'

# Render with values
template_rs_cli render \
    -t struct.template_rs \
    -v struct_name=User \
    -v fields="name: String,\n    age: u32" \
    -v field_values="name: String::from(\"Alice\"),\n    age: 30" \
    -o user.rs

Web Request Template

# Create template with dependencies
template_rs_cli execute \
    -t api.template_rs \
    -v url="https://api.example.com" \
    -v method="get" \
    -d "reqwest=0.11" \
    -d "tokio=1.0"

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.

License

This project is licensed under the MIT License - see the LICENSE file for details.

Safety Notes

• Validate template content before execution
• Be cautious with user-provided input
• Review dependencies before execution
• Consider using template sandboxing in production environments