jobs/sync_to_sparse_index: Add Fastly CDN support

Author: Turbo87

src/config/server.rs

@@ -99,6 +99,9 @@ pub struct Server {
 
     /// Include publication timestamp in index entries (ISO8601 format).
     pub index_include_pubtime: bool,
+
+    /// Enable Fastly CDN invalidation for sparse index files.
+    pub sparse_index_fastly_enabled: bool,
 }
 
 impl Server {
@@ -248,6 +251,8 @@ impl Server {
             disable_token_creation,
             banner_message,
             index_include_pubtime,
+            sparse_index_fastly_enabled: var_parsed("SPARSE_INDEX_FASTLY_ENABLED")?
+                .unwrap_or(false),
         })
     }
 }

src/worker/jobs/index/sync.rs

@@ -12,7 +12,7 @@ use std::fs::File;
 use std::io::{ErrorKind, Write};
 use std::sync::Arc;
 use std::time::Instant;
-use tracing::{debug, info, instrument};
+use tracing::{debug, info, instrument, warn};
 
 #[derive(Serialize, Deserialize)]
 pub struct SyncToGitIndex {
@@ -121,9 +121,28 @@ impl BackgroundJob for SyncToSparseIndex {
         let future = env.storage.sync_index(&self.krate, content);
         future.await.context("Failed to sync index data")?;
 
-        if env.cloudfront().is_some() {
-            let path = Repository::relative_index_file_for_url(&self.krate);
+        let path = Repository::relative_index_file_for_url(&self.krate);
+
+        if let Some(fastly) = env.fastly()
+            && env.config.sparse_index_fastly_enabled
+        {
+            let domain_name = &env.config.domain_name;
+            let domains = [
+                format!("index.{}", domain_name),
+                format!("fastly-index.{}", domain_name),
+            ];
+
+            for domain in domains {
+                if let Err(error) = fastly.purge(&domain, &path).await {
+                    warn!(
+                        domain,
+                        path, "Failed to invalidate sparse index on Fastly: {error}"
+                    );
+                }
+            }
+        }
 
+        if env.cloudfront().is_some() {
             info!(%path, "Queuing index file invalidation on CloudFront");
 
             let paths = &[path];