[pbs-devel] [PATCH proxmox v4 1/1] s3 client: extend client config and options by optional provider quirks

[Christian Ebner]

Add optional provider specific quirks as array to the client
configuration and client options, allowing to set a variant of the
client to follow some custom implementation variants.

As first variant, add the quirk to skip setting the `If-None-Match`
header in put object requests, as some providers do not accept and
implement this headers functionality.

Signed-off-by: Christian Ebner <c.ebner at proxmox.com>
---
changes since version 3:
- Drop provider list to feature list mapping, use and expose provider
  quirks directly.
- Squashed together with next patch, as this is now pretty much self
  contained

 proxmox-s3-client/examples/s3_client.rs |  1 +
 proxmox-s3-client/src/api_types.rs      | 21 +++++++++++++++++++++
 proxmox-s3-client/src/client.rs         | 15 +++++++++++++--
 3 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/proxmox-s3-client/examples/s3_client.rs b/proxmox-s3-client/examples/s3_client.rs
index 4a9625cb..61b88077 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,
+        provider_quirks: 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 265fedb9..c68d85ef 100644
--- a/proxmox-s3-client/src/api_types.rs
+++ b/proxmox-s3-client/src/api_types.rs
@@ -80,6 +80,17 @@ pub const S3_BUCKET_NAME_SCHEMA: Schema = StringSchema::new("Bucket name for S3
     .max_length(63)
     .schema();
 
+#[api]
+#[derive(Copy, Clone, Deserialize, Serialize, PartialEq, Eq)]
+#[serde(rename_all = "kebab-case")]
+/// Provider specific feature implementation quirks.
+pub enum ProviderQuirks {
+    /// Prvider does not support the If-None-Match http header
+    SkipIfNoneMatchHeader,
+}
+serde_plain::derive_display_from_serialize!(ProviderQuirks);
+serde_plain::derive_fromstr_from_deserialize!(ProviderQuirks);
+
 #[api(
     properties: {
         endpoint: {
@@ -109,6 +120,13 @@ pub const S3_BUCKET_NAME_SCHEMA: Schema = StringSchema::new("Bucket name for S3
             type: u64,
             optional: true,
         },
+        "provider-quirks": {
+            type: Array,
+            optional: true,
+            items: {
+                type: ProviderQuirks,
+            },
+        },
     },
 )]
 #[derive(Serialize, Deserialize, Updater, Clone, PartialEq)]
@@ -134,6 +152,9 @@ pub struct S3ClientConfig {
     /// Rate limit for put requests given as #reqest/s.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub put_rate_limit: Option<u64>,
+    /// List of provider specific feature implementation quirks.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub provider_quirks: Option<Vec<ProviderQuirks>>,
 }
 
 impl S3ClientConfig {
diff --git a/proxmox-s3-client/src/client.rs b/proxmox-s3-client/src/client.rs
index ae61c590..3bc2a672 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};
 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 provider_quirks: Vec<ProviderQuirks>,
 }
 
 impl S3ClientOptions {
@@ -90,6 +92,7 @@ impl S3ClientOptions {
             access_key: config.access_key,
             secret_key,
             put_rate_limit: config.put_rate_limit,
+            provider_quirks: config.provider_quirks.unwrap_or_default(),
         }
     }
 }
@@ -411,7 +414,15 @@ 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
+                .provider_quirks
+                .contains(&ProviderQuirks::SkipIfNoneMatchHeader)
+            {
+                request = request.header(header::IF_NONE_MATCH, "*");
+            }
         }
 
         let request = request.body(object_data)?;
-- 
2.47.2