load builder toolchain from database instead of environment

src/bin/cratesfyi.rs

@@ -12,7 +12,7 @@ use docs_rs::db::{self, add_path_into_database, Overrides, Pool, PoolClient};
 use docs_rs::repositories::RepositoryStatsUpdater;
 use docs_rs::utils::{
     get_config, get_crate_pattern_and_priority, list_crate_priorities, queue_builder,
-    remove_crate_priority, set_crate_priority, ConfigName,
+    remove_crate_priority, set_config, set_crate_priority, ConfigName,
 };
 use docs_rs::{
     start_background_metrics_webserver, start_web_server, BuildQueue, Config, Context, Index,
@@ -383,6 +383,10 @@ enum BuildSubcommand {
     /// Adds essential files for the installed version of rustc
     AddEssentialFiles,
 
+    SetToolchain {
+        toolchain_name: String,
+    },
+
     /// Locks the daemon, preventing it from building new crates
     Lock,
 
@@ -459,6 +463,15 @@ impl BuildSubcommand {
                     .context("failed to add essential files")?;
             }
 
+            Self::SetToolchain { toolchain_name } => {
+                let mut conn = ctx
+                    .pool()?
+                    .get()
+                    .context("failed to get a database connection")?;
+                set_config(&mut conn, ConfigName::Toolchain, toolchain_name)
+                    .context("failed to set toolchain in database")?;
+            }
+
             Self::Lock => build_queue.lock().context("Failed to lock")?,
             Self::Unlock => build_queue.unlock().context("Failed to unlock")?,
         }

src/config.rs

@@ -99,7 +99,6 @@ pub struct Config {
     pub(crate) rustwide_workspace: PathBuf,
     pub(crate) inside_docker: bool,
     pub(crate) docker_image: Option<String>,
-    pub(crate) toolchain: String,
     pub(crate) build_cpu_limit: Option<u32>,
     pub(crate) build_default_memory_limit: Option<usize>,
     pub(crate) include_default_targets: bool,
@@ -113,7 +112,6 @@ impl Config {
             ("CRATESFYI_DATABASE_URL", "DOCSRS_DATABASE_URL"),
             ("CRATESFYI_GITHUB_ACCESSTOKEN", "DOCSRS_GITHUB_ACCESSTOKEN"),
             ("CRATESFYI_RUSTWIDE_WORKSPACE", "DOCSRS_RUSTWIDE_WORKSPACE"),
-            ("CRATESFYI_TOOLCHAIN", "DOCSRS_TOOLCHAIN"),
             ("DOCS_RS_DOCKER", "DOCSRS_DOCKER"),
             ("DOCS_RS_LOCAL_DOCKER_IMAGE", "DOCSRS_DOCKER_IMAGE"),
             ("DOCS_RS_BULID_CPU_LIMIT", "DOCSRS_BULID_CPU_LIMIT"),
@@ -202,7 +200,6 @@ impl Config {
             inside_docker: env("DOCSRS_DOCKER", false)?,
             docker_image: maybe_env("DOCSRS_LOCAL_DOCKER_IMAGE")?
                 .or(maybe_env("DOCSRS_DOCKER_IMAGE")?),
-            toolchain: env("DOCSRS_TOOLCHAIN", "nightly".to_string())?,
             build_cpu_limit: maybe_env("DOCSRS_BUILD_CPU_LIMIT")?,
             build_default_memory_limit: maybe_env("DOCSRS_BUILD_DEFAULT_MEMORY_LIMIT")?,
             include_default_targets: env("DOCSRS_INCLUDE_DEFAULT_TARGETS", true)?,

src/docbuilder/rustwide_builder.rs

@@ -8,8 +8,8 @@ use crate::error::Result;
 use crate::repositories::RepositoryStatsUpdater;
 use crate::storage::{rustdoc_archive_path, source_archive_path};
 use crate::utils::{
-    copy_dir_all, parse_rustc_version, queue_builder, report_error, set_config, CargoMetadata,
-    ConfigName,
+    copy_dir_all, get_config, parse_rustc_version, queue_builder, report_error, set_config,
+    CargoMetadata, ConfigName,
 };
 use crate::RUSTDOC_STATIC_STORAGE_PREFIX;
 use crate::{db::blacklist::is_blacklisted, utils::MetadataPackage};
@@ -33,6 +33,21 @@ const COMPONENTS: &[&str] = &["llvm-tools-preview", "rustc-dev", "rustfmt"];
 const DUMMY_CRATE_NAME: &str = "empty-library";
 const DUMMY_CRATE_VERSION: &str = "1.0.0";
 
+fn get_configured_toolchain(conn: &mut Client) -> Result<Toolchain> {
+    let name: String = get_config(conn, ConfigName::Toolchain)?.unwrap_or_else(|| "nightly".into());
+
+    // If the toolchain is all hex, assume it references an artifact from
+    // CI, for instance an `@bors try` build.
+    let re = Regex::new(r"^[a-fA-F0-9]+$").unwrap();
+    if re.is_match(&name) {
+        debug!("using CI build {}", &name);
+        Ok(Toolchain::ci(&name, false))
+    } else {
+        debug!("using toolchain {}", &name);
+        Ok(Toolchain::dist(&name))
+    }
+}
+
 pub enum PackageKind<'a> {
     Local(&'a Path),
     CratesIo,
@@ -75,22 +90,13 @@ impl RustwideBuilder {
             .purge_all_build_dirs()
             .map_err(FailureError::compat)?;
 
-        // If the toolchain is all hex, assume it references an artifact from
-        // CI, for instance an `@bors try` build.
-        let re = Regex::new(r"^[a-fA-F0-9]+$").unwrap();
-        let toolchain = if re.is_match(&config.toolchain) {
-            debug!("using CI build {}", &config.toolchain);
-            Toolchain::ci(&config.toolchain, false)
-        } else {
-            debug!("using toolchain {}", &config.toolchain);
-            Toolchain::dist(&config.toolchain)
-        };
+        let pool = context.pool()?;
 
         Ok(RustwideBuilder {
             workspace,
-            toolchain,
+            toolchain: get_configured_toolchain(&mut *pool.get()?)?,
             config,
-            db: context.pool()?,
+            db: pool,
             storage: context.storage()?,
             metrics: context.instance_metrics()?,
             index: context.index()?,
@@ -119,6 +125,8 @@ impl RustwideBuilder {
     }
 
     pub fn update_toolchain(&mut self) -> Result<bool> {
+        self.toolchain = get_configured_toolchain(&mut *self.db.get()?)?;
+
         // For CI builds, a lot of the normal update_toolchain things don't apply.
         // CI builds are only for one platform (https://forge.rust-lang.org/infra/docs/rustc-ci.html#try-builds)
         // so we only try installing for the current platform. If that's not a match,

src/utils/mod.rs

@@ -56,6 +56,7 @@ pub enum ConfigName {
     RustcVersion,
     LastSeenIndexReference,
     QueueLocked,
+    Toolchain,
 }
 
 pub fn set_config(