Serde TXT Record

A Rust serialization and deserialization library for TXT record format using Serde.

This library provides custom serde support for converting Rust data structures to and from TXT record format commonly used in DNS TXT records and configuration files.

• Simple key-value pairs: key: value → key=value
• Arrays: key: ["val", "bal"] → key_0=val, key_1=bal, key_len=2
• Objects: key: { foo: "val", bar: "bal" } → key.foo=val, key.bar=bal
• Record length limits: Each key=value record can be limited to a maximum length (default: 255 characters)
• Configurable separators and suffixes: Customize array separators, object separators, and array length suffixes
• All Rust primitive types: Support for strings, numbers, booleans, options, and more

This library is particularly useful for:

• DNS TXT Records: Storing structured configuration in DNS TXT records
• Configuration Files: Simple key-value configuration format
• Environment Variables: Flattening complex structures for environment variable storage
• Log Structured Data: Converting structured data to searchable key-value pairs
• API Parameters: Flattening nested objects for form-encoded or query parameters

Installation

Add this to your Cargo.toml:

[dependencies]
serde-txtrecord = "0.1.0"
serde = { version = "1.0", features = ["derive"] }

Usage

You can use the to_txt_records and from_txt_records functions on a struct that has the Serialize and Deserialize traits, respectively.

use serde::{Serialize, Deserialize};
use serde_txtrecord::{to_txt_records, from_txt_records};

#[derive(Serialize, Deserialize, Debug, PartialEq)]
struct Person {
    name: String,
    age: u32,
    active: bool,
}

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let person = Person {
        name: "Alice".to_string(),
        age: 30,
        active: true,
    };

    // serialize to TXT records
    let records = to_txt_records(&person)?;
    // > name=Alice
    // > age=30
    // > active=true

    // Deserialize back from TXT records
    let deserialized: Person = from_txt_records(records)?;
    assert_eq!(person, deserialized);

    Ok(())
}

You can provide a custom configuration as well, to avoid clashing names; use with to_txt_records_with_config and from_txt_records_with_config.

use serde_txtrecord::{to_txt_records_with_config, TxtRecordConfig};

let config = TxtRecordConfig {
    array_separator: "-".to_string(),         // use "-" instead of "_" for arrays
    object_separator: "/".to_string(),        // use "/" instead of "." for objects
    record_len: 100,                          // limit records to 100 characters
    array_len_suffix: ".count".to_string(),   // use ".count" instead of "_len"
};

let data = vec!["item1", "item2", "item3"];
let records = to_txt_records_with_config(&data, config)?;
// 0-0=item1
// 0-1=item2
// 0-2=item3
// 0.count=3

Testing

Run the test suite:

cargo test

# run an example
cargo run --example complex

Contributing

Contributions are welcome! Please feel free to submit a Pull Request. For major changes, please open an issue first to discuss what you would like to change.

License

This project is licensed under the MIT License.