[pbs-devel] [PATCH proxmox v2 2/2] s3 client: extend client options by feature list

[Christian Ebner]

Adds a feature list to the s3 client options, which allows to define
a set of provider specific implementation features or limitations to
be used by the client.

As a first limitation, the SkipIfNoneMatchHeader is added for
provider not accepting and implementing this headers functionality.

Defines also an associated helper function on S3ClientOptions to map
a given provider quirk to a feature list.

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
changes since version 1:
- use feature list instead of provider for s3 client options, adding
  flexibility for further extension
- add helper to map from provider quirk to feature list
- set If-None-Match header based on feature instead of provider quirk

 proxmox-s3-client/examples/s3_client.rs |  1 +
 proxmox-s3-client/src/api_types.rs      | 11 +++++++++++
 proxmox-s3-client/src/client.rs         | 26 +++++++++++++++++++++++--
 3 files changed, 36 insertions(+), 2 deletions(-)

diff --git a/proxmox-s3-client/examples/s3_client.rs b/proxmox-s3-client/examples/s3_client.rs
index 1cbb3939..21b0e9ce 100644
--- a/proxmox-s3-client/examples/s3_client.rs
+++ b/proxmox-s3-client/examples/s3_client.rs
@@ -38,6 +38,7 @@ async fn run() -> Result<(), anyhow::Error> {
         // `openssl s_client -connect testbucket.s3.pve-c1.local:7480 < /dev/null | openssl x509 -fingerprint -sha256 -noout`
         fingerprint: Some("<s3-api-fingerprint>".to_string()),
         put_rate_limit: None,
+        features: Vec::new(),
     };
 
     // Creating a client instance and connect to api endpoint
diff --git a/proxmox-s3-client/src/api_types.rs b/proxmox-s3-client/src/api_types.rs
index 7d1ad24e..a87e0804 100644
--- a/proxmox-s3-client/src/api_types.rs
+++ b/proxmox-s3-client/src/api_types.rs
@@ -211,3 +211,14 @@ pub struct S3ClientConfigWithoutSecret {
     #[serde(flatten)]
     pub config: S3ClientConfig,
 }
+
+#[api]
+#[derive(Copy, Clone, Deserialize, Serialize, PartialEq, Eq)]
+#[serde(rename_all = "kebab-case")]
+/// Provider specific implementation feature or limitation.
+pub enum S3ClientFeature {
+    /// If-None-Match http header not implemented and not accepted.
+    SkipIfNoneMatchHeader,
+}
+serde_plain::derive_display_from_serialize!(S3ClientFeature);
+serde_plain::derive_fromstr_from_deserialize!(S3ClientFeature);
diff --git a/proxmox-s3-client/src/client.rs b/proxmox-s3-client/src/client.rs
index 3a981bf4..ce57722a 100644
--- a/proxmox-s3-client/src/client.rs
+++ b/proxmox-s3-client/src/client.rs
@@ -22,7 +22,7 @@ use proxmox_http::client::HttpsConnector;
 use proxmox_http::{Body, RateLimit, RateLimiter};
 use proxmox_schema::api_types::CERT_FINGERPRINT_SHA256_SCHEMA;
 
-use crate::api_types::S3ClientConfig;
+use crate::api_types::{ProviderQuirks, S3ClientConfig, S3ClientFeature};
 use crate::aws_sign_v4::AWS_SIGN_V4_DATETIME_FORMAT;
 use crate::aws_sign_v4::{aws_sign_v4_signature, aws_sign_v4_uri_encode};
 use crate::object_key::S3ObjectKey;
@@ -69,6 +69,8 @@ pub struct S3ClientOptions {
     pub fingerprint: Option<String>,
     /// Rate limit for put requests given as #reqest/s.
     pub put_rate_limit: Option<u64>,
+    /// Provider implementation specific features and limitations
+    pub features: Vec<S3ClientFeature>,
 }
 
 impl S3ClientOptions {
@@ -90,6 +92,18 @@ impl S3ClientOptions {
             access_key: config.access_key,
             secret_key,
             put_rate_limit: config.put_rate_limit,
+            features: Self::map_provider_quirks_to_features(config.provider_quirks),
+        }
+    }
+
+    fn map_provider_quirks_to_features(
+        provider_quirks: Option<ProviderQuirks>,
+    ) -> Vec<S3ClientFeature> {
+        match provider_quirks {
+            Some(ProviderQuirks::Backblaze) | Some(ProviderQuirks::Infomaniak) => {
+                vec![S3ClientFeature::SkipIfNoneMatchHeader]
+            }
+            _ => Vec::new(),
         }
     }
 }
@@ -393,7 +407,15 @@ impl S3Client {
             .header(header::CONTENT_TYPE, "binary/octet");
 
         if !replace {
-            request = request.header(header::IF_NONE_MATCH, "*");
+            // Some providers not implement this and fails with error if the header is set,
+            // see https://forum.proxmox.com/threads/168834/post-786278
+            if !self
+                .options
+                .features
+                .contains(&S3ClientFeature::SkipIfNoneMatchHeader)
+            {
+                request = request.header(header::IF_NONE_MATCH, "*");
+            }
         }
 
         let request = request.body(object_data)?;
-- 
2.47.2