feat: add tool-specific config extension and default config discovery

Cargo.toml

@@ -133,39 +133,38 @@ tracing-subscriber = { version = "0.3", features = [
 ] }
 tracing-test = "0.2.6"
 
-# rattler crates
 # Rattler crates
-rattler_conda_types = { version = "0.47.2", default-features = false }
+rattler_conda_types = { version = "0.48", default-features = false }
 rattler_digest = { version = "1.3.1", default-features = false, features = [
   "serde",
 ] }
-rattler_networking = { version = "0.30.0", default-features = false }
-rattler_package_streaming = { version = "0.26.5", default-features = false }
-rattler_shell = { version = "0.27.7", default-features = false, features = [
+rattler_networking = { version = "0.30", default-features = false }
+rattler_package_streaming = { version = "0.26", default-features = false }
+rattler_shell = { version = "0.27", default-features = false, features = [
   "sysinfo",
 ] }
 rattler_git = { version = "0.1.3" }
 rattler_prefix_guard = { version = "0.1.1" }
 
-rattler_config = { version = "0.5.2" }
-rattler = { version = "0.46.0", default-features = false, features = [
+rattler_config = { version = "0.6" }
+rattler = { version = "0.47", default-features = false, features = [
   "cli-tools",
   "indicatif",
 ] }
-rattler_cache = { version = "0.10.0", default-features = false }
-rattler_index = { version = "0.30.5", default-features = false }
-rattler_upload = { version = "0.8.0", default-features = false }
+rattler_cache = { version = "0.10", default-features = false }
+rattler_index = { version = "0.30", default-features = false }
+rattler_upload = { version = "0.8", default-features = false }
 rattler_s3 = { version = "0.2.5" }
 rattler_redaction = { version = "0.2.1", default-features = false }
-rattler_repodata_gateway = { version = "0.29.6", default-features = false, features = [
+rattler_repodata_gateway = { version = "0.30", default-features = false, features = [
   "gateway",
 ] }
-rattler_solve = { version = "7.1.4", default-features = false, features = [
+rattler_solve = { version = "7.2", default-features = false, features = [
   "resolvo",
   "serde",
 ] }
-rattler_virtual_packages = { version = "3.0.2", default-features = false }
-rattler_menuinst = "0.2.67"
+rattler_virtual_packages = { version = "3.0", default-features = false }
+rattler_menuinst = "0.2"
 
 
 # Internal rattler-build crates

crates/rattler_build_core/src/build.rs

@@ -57,7 +57,8 @@ pub async fn skip_existing(
 
     let channels = if only_local {
         vec![
-            Channel::from_directory(&first_output.build_configuration.directories.output_dir)
+            Channel::try_from_directory(&first_output.build_configuration.directories.output_dir)
+                .expect("could not create channel from directory")
                 .base_url,
         ]
     } else {

crates/rattler_build_core/src/package_test/run_test.rs

@@ -507,7 +507,12 @@ pub async fn run_test(
     let package_folder = cache_metadata.path().to_path_buf();
 
     let mut channels = config.channels.clone();
-    channels.insert(0, Channel::from_directory(tmp_repo.path()).base_url);
+    channels.insert(
+        0,
+        Channel::try_from_directory(tmp_repo.path())
+            .expect("could not create channel from directory")
+            .base_url,
+    );
 
     let host_platform = config.host_platform.clone().unwrap_or_else(|| {
         if target_platform == Platform::NoArch {

crates/rattler_build_core/src/publish.rs

@@ -144,6 +144,11 @@ pub async fn fetch_highest_build_numbers(
 
     match result {
         Ok(repo_data) => {
+            // Surface any non-fatal warnings gathered during the query
+            // instead of dropping them.
+            for warning in &repo_data.warnings {
+                tracing::warn!("{warning}");
+            }
             for repo in repo_data {
                 for record in repo.iter() {
                     let name = &record.package_record.name;

crates/rattler_build_core/src/render/solver.rs

@@ -208,7 +208,15 @@ pub async fn load_repodatas(
         .clear()
         .unwrap();
 
-    Ok(result)
+    // `query` returns a `RepoDataQueryOutput`: repodata records plus any
+    // non-fatal warnings gathered during the query (e.g. CEP-42 channel
+    // relations). Surface the warnings to the user instead of dropping them,
+    // then return the records.
+    for warning in &result.warnings {
+        tracing::warn!("{warning}");
+    }
+
+    Ok(result.repodata)
 }
 
 pub async fn install_packages(

crates/rattler_build_core/src/types/mod.rs

@@ -161,7 +161,8 @@ pub async fn build_reindexed_channels(
         return Ok(build_configuration.channels.clone());
     }
 
-    let output_channel = Channel::from_directory(output_dir);
+    let output_channel =
+        Channel::try_from_directory(output_dir).expect("could not create channel from directory");
 
     // Clear the repodata gateway of any cached values for the output channel.
     // Clear all subdirs so that packages from other platforms (e.g. a linux-64

crates/rattler_build_playground/Cargo.toml

@@ -26,7 +26,7 @@ rattler_build_jinja = { path = "../rattler_build_jinja" }
 rattler_build_types = { path = "../rattler_build_types" }
 rattler_build_yaml_parser = { path = "../rattler_build_yaml_parser" }
 indexmap = "2"
-rattler_conda_types = { version = "0.47.2", default-features = false }
+rattler_conda_types = { version = "0.48", default-features = false }
 serde_yaml = "0.9"
 arborium = { version = "2", default-features = false, features = ["lang-yaml"] }
 

docs/config.md

@@ -1,7 +1,33 @@
 # Rattler-Build configuration
 
-Rattler-Build can be configured by specifying `--config-file ~/.pixi/config.toml`.
-The config file is of the same format as pixi's [global configuration file](https://pixi.sh/latest/reference/pixi_configuration/).
+Rattler-Build shares its configuration format with pixi: the config file is of the same format as pixi's [global configuration file](https://pixi.sh/latest/reference/pixi_configuration/).
+
+By default (when no `--config-file` is passed), Rattler-Build automatically loads and merges configuration from the standard locations shared by all rattler based tools. Discovery is provided by `rattler_config`'s common `locations` helper, so the search order is identical to the one pixi and other tools use. The locations, in ascending order of precedence (values from later files override values from earlier files):
+
+1. The system-wide configuration of each tool: `/etc/pixi/config.toml` followed by `/etc/rattler-build/config.toml` (on Windows: `C:\ProgramData\<tool>\config.toml`)
+2. The per-user configuration of each tool: the platform config directory (`$XDG_CONFIG_HOME/<tool>/config.toml`, e.g. `~/.config/pixi/config.toml`) and the tool home (`$PIXI_HOME` / `$RATTLER_BUILD_HOME`, defaulting to `~/.pixi/config.toml` / `~/.rattler-build/config.toml`), for `pixi` first and then `rattler-build`
+
+In other words all system-wide files are read before any per-user file, and within each group pixi's files are overridden by Rattler-Build's own files. This means that settings such as default channels, mirrors, or S3 options that you have configured for pixi are picked up by Rattler-Build automatically, and can be overridden in Rattler-Build's own configuration files.
+
+Alternatively, a single configuration file can be specified explicitly with `--config-file` (e.g. `--config-file ~/.pixi/config.toml`), which disables the automatic discovery and loads only that file. To disable configuration entirely — so that only built-in defaults and command-line arguments apply — pass `--no-config` (mutually exclusive with `--config-file`).
+
+!!! note "Behavior change"
+    Earlier versions of Rattler-Build only loaded configuration when `--config-file` was passed. Automatic discovery of the locations above is new: if you already have a pixi configuration, Rattler-Build now picks it up by default. Pass `--no-config` to restore the old behavior and skip all configuration loading, or `--config-file` to load only a specific file.
+
+## Seeing which configuration was loaded
+
+On startup Rattler-Build logs its version and the configuration files it actually loaded, so you can always trace where a setting came from:
+
+```
+rattler-build 0.68.0
+Loaded configuration from: /etc/pixi/config.toml, /home/user/.pixi/config.toml
+```
+
+If no configuration file was found — either because none of the default locations exist, or because `--config-file` was not given — it logs `No configuration file loaded` instead. These lines appear at the default log level; run with `-v` to additionally see the full list of candidate paths that were considered (useful when a file you expected is not picked up).
+
+## Programmatic use
+
+Automatic discovery happens **only when you run the `rattler-build` command-line tool**. When Rattler-Build is used as a library (for example from [pixi](https://pixi.sh), or through the Python bindings), no configuration is loaded implicitly — the embedding application constructs the configuration and passes it in. This guarantees that using Rattler-Build programmatically never silently reads your global pixi or Rattler-Build configuration from disk.
 
 ## Channels
 

docs/reference/cli/rattler-build.md

@@ -41,7 +41,9 @@ rattler-build [OPTIONS] [COMMAND]
 <br>**env**: `RATTLER_BUILD_WRAP_LOG_LINES`
 <br>**options**: `true`, `false`
 - <a id="arg---config-file" href="#arg---config-file">`--config-file <CONFIG_FILE>`</a>
-:  The Rattler-Build configuration file to use
+:  The Rattler-Build configuration file to use. If not set, configuration is loaded from the default locations (the system-wide and global pixi configuration files as well as rattler-build's own configuration files)
+- <a id="arg---no-config" href="#arg---no-config">`--no-config`</a>
+:  Do not load any configuration. Disables the automatic discovery of pixi/rattler-build configuration files so that only built-in defaults and command-line arguments are used (the behavior of rattler-build versions before default config discovery was added). Mutually exclusive with `--config-file`
 - <a id="arg---color" href="#arg---color">`--color <COLOR>`</a>
 :  Enable or disable colored output from Rattler-Build. Also honors the `CLICOLOR` and `CLICOLOR_FORCE` environment variable
 <br>**env**: `RATTLER_BUILD_COLOR`

docs/reference/cli/rattler-build/auth/status.md

@@ -12,5 +12,5 @@ rattler-build auth status [OPTIONS]
 ```
 
 ## Options
-- <a id="arg---verbose" href="#arg---verbose">`--verbose (-v)`</a>
+- <a id="arg---details" href="#arg---details">`--details`</a>
 :  Show endpoint URLs, client ID, and other IdP-introspection fields that are only useful for debugging