tanzim-load

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First stage of the tanzim pipeline: reads raw configuration bytes from a declared source.

The Load trait

Implement [Load] to add a new source kind (protocol, service, database, …). It only fetches bytes — parsing happens in a later stage. The contract:

• Return one [Payload] per config entry found; a single source may expand to many entries. Finding nothing is Ok(vec![]), not an error.
• Set Payload::source on each entry to the concrete resource loaded (narrow the incoming source with Source::with_resource) so diagnostics stay precise.
• Payload::maybe_name is the entry name (None merges into the root); Payload::maybe_format is a parser hint (e.g. json).
• Read options off the source with Source::options() and the typed OptionValue accessors, and pick the [Error] variant that matches the failure (InvalidResource, InvalidOption, NotFound, NoAccess, Timeout, Duplicate, Load).

Register a loader with tanzim::Config::with_loader; it's dispatched by the source strings its supported_source_list() returns. For a quick, stateless adapter, use closure::Closure instead of a full impl Load. See the [Load] rustdoc and the custom_loader example for worked details.

Built-in loaders

Example

use std::env;
use tanzim_load::{env::Env, Error, Load, Source};

fn main() -> Result<(), Error> {
    // SAFETY: example-only; single-threaded doctest env vars.
    unsafe {
        env::set_var("MY_APP_CFG.DEBUG", "true");
        env::set_var("MY_APP_CFG.NAME", "hello");
        env::set_var("MY_APP_CFG.DATABASE.HOST", "localhost");
    }

    let source = Source::parse(r#"env(prefix=MY_APP_,separator=".")"#).unwrap();

    let payloads = Env::new().load(source)?;
    assert_eq!(payloads.len(), 1);

    let payload = payloads[0].clone();
    assert_eq!(payload.maybe_name, Some("cfg".into()));
    assert_eq!(payload.maybe_format, Some("env".into()));

    let content = String::from_utf8_lossy(&payload.content);
    assert!(content.contains("DEBUG=\"true\""));
    assert!(content.contains("NAME=\"hello\""));
    assert!(content.contains("DATABASE.HOST=\"localhost\""));

    Ok(())
}

Features

Default features: env, file, http. Logging/tracing are opt-in.

Relations

• Depends on tanzim-source for Source and Options.
• Produces Payload values consumed by tanzim-parse.
• Full pipeline wired in tanzim.