More headers cleanup (#864)

* Consistent header method naming

* Parse more headers

Author: rylev

sdk/core/src/error/http_error.rs

@@ -71,7 +71,7 @@ impl std::error::Error for HttpError {}
 ///
 /// For more info, see [here](https://github.com/microsoft/api-guidelines/blob/vNext/azure/Guidelines.md#handling-errors)
 fn get_error_code_from_header(response: &Response) -> Option<String> {
-    response.headers().get_as_string(&headers::ERROR_CODE)
+    response.headers().get_optional_string(&headers::ERROR_CODE)
 }
 
 /// Gets the error code if it's present in the body

sdk/core/src/headers/mod.rs

@@ -59,68 +59,78 @@ impl Headers {
         Self(Default::default())
     }
 
-    /// Get a header value given a specific header name
-    pub fn get(&self, key: &HeaderName) -> Option<&HeaderValue> {
-        self.0.get(key)
-    }
-
-    /// Get a header value or error if it is not found
-    pub fn get_or_err(&self, key: &HeaderName) -> crate::Result<&HeaderValue> {
-        self.get(key).ok_or_else(|| {
-            Error::with_message(ErrorKind::DataConversion, || {
-                format!("header not found {}", key.as_str())
-            })
-        })
+    /// Get a header value as a String or error if it is not found
+    pub fn get_string(&self, key: &HeaderName) -> crate::Result<String> {
+        Ok(self.get_str(key)?.to_owned())
     }
 
-    /// Get a header value as a str
-    pub fn get_as_str(&self, key: &HeaderName) -> Option<&str> {
-        self.get(key).map(|v| v.as_str())
+    /// Optionally get a header value as a String
+    pub fn get_optional_string(&self, key: &HeaderName) -> Option<String> {
+        self.get_string(key).ok()
     }
 
     /// Get a header value as a str or error if it is not found
-    pub fn get_as_str_or_err(&self, key: &HeaderName) -> crate::Result<&str> {
-        self.get_or_err(key).map(|v| v.as_str())
+    pub fn get_str(&self, key: &HeaderName) -> crate::Result<&str> {
+        self.get_with(key, |s| crate::Result::Ok(s.as_str()))
     }
 
-    /// Get a header value as a String
-    pub fn get_as_string(&self, key: &HeaderName) -> Option<String> {
-        self.get(key).map(|v| v.as_str().to_string())
+    /// Optionally get a header value as a str
+    pub fn get_optional_str(&self, key: &HeaderName) -> Option<&str> {
+        self.get_str(key).ok()
     }
 
-    /// Get a header value as a String or error if it is not found
-    pub fn get_as_string_or_err(&self, key: &HeaderName) -> crate::Result<String> {
-        self.get_or_err(key).map(|v| v.as_str().to_string())
+    /// Get a header value parsing it as the type or error if it's not found or it fails to parse
+    pub fn get_as<V, E>(&self, key: &HeaderName) -> crate::Result<V>
+    where
+        V: FromStr<Err = E>,
+        E: std::error::Error + Send + Sync + 'static,
+    {
+        self.get_with(key, |s| s.as_str().parse())
     }
 
+    /// Optionally get a header value parsing it as the type or error if it fails to parse
     pub fn get_optional_as<V, E>(&self, key: &HeaderName) -> crate::Result<Option<V>>
     where
         V: FromStr<Err = E>,
         E: std::error::Error + Send + Sync + 'static,
     {
-        self.get(key)
-            .map(|v: &HeaderValue| {
-                let v = v.as_str();
-                v.parse::<V>().with_context(ErrorKind::DataConversion, || {
-                    let ty = std::any::type_name::<V>();
-                    format!("unable to parse header '{key:?}: {v}' into {ty}",)
-                })
-            })
-            .transpose()
+        self.get_optional_with(key, |s| s.as_str().parse())
     }
 
-    pub fn get_as<V, E>(&self, key: &HeaderName) -> crate::Result<V>
+    /// Get a header value using the parser or error if it is not found or fails to parse
+    pub fn get_with<'a, V, F, E>(&'a self, key: &HeaderName, parser: F) -> crate::Result<V>
     where
-        V: FromStr<Err = E>,
+        F: FnOnce(&'a HeaderValue) -> Result<V, E>,
         E: std::error::Error + Send + Sync + 'static,
     {
-        self.get_optional_as(key)?.ok_or_else(|| {
-            Error::with_message(ErrorKind::Other, || {
+        self.get_optional_with(key, parser)?.ok_or_else(|| {
+            Error::with_message(ErrorKind::DataConversion, || {
                 format!("header not found {}", key.as_str())
             })
         })
     }
 
+    /// Optionally get a header value using the parser or error if it fails to parse
+    pub fn get_optional_with<'a, V, F, E>(
+        &'a self,
+        key: &HeaderName,
+        parser: F,
+    ) -> crate::Result<Option<V>>
+    where
+        F: FnOnce(&'a HeaderValue) -> Result<V, E>,
+        E: std::error::Error + Send + Sync + 'static,
+    {
+        self.0
+            .get(key)
+            .map(|v: &HeaderValue| {
+                parser(v).with_context(ErrorKind::DataConversion, || {
+                    let ty = std::any::type_name::<V>();
+                    format!("unable to parse header '{key:?}: {v:?}' into {ty}",)
+                })
+            })
+            .transpose()
+    }
+
     /// Insert a header name/value pair
     pub fn insert<K, V>(&mut self, key: K, value: V)
     where

sdk/core/src/headers/utilities.rs

@@ -36,7 +36,7 @@ pub fn request_id_from_headers(headers: &Headers) -> crate::Result<RequestId> {
 }
 
 pub fn client_request_id_from_headers_optional(headers: &Headers) -> Option<String> {
-    headers.get_as_string(&CLIENT_REQUEST_ID)
+    headers.get_optional_string(&CLIENT_REQUEST_ID)
 }
 
 pub fn last_modified_from_headers_optional(
@@ -57,7 +57,7 @@ pub fn rfc2822_from_headers_mandatory(
     headers: &Headers,
     header_name: &HeaderName,
 ) -> crate::Result<DateTime<Utc>> {
-    let date = headers.get_as_str_or_err(header_name)?;
+    let date = headers.get_str(header_name)?;
     utc_date_from_rfc2822(date)
 }
 
@@ -69,23 +69,23 @@ pub fn utc_date_from_rfc2822(date: &str) -> crate::Result<DateTime<Utc>> {
 pub fn continuation_token_from_headers_optional(
     headers: &Headers,
 ) -> crate::Result<Option<String>> {
-    Ok(headers.get_as_string(&CONTINUATION))
+    Ok(headers.get_optional_string(&CONTINUATION))
 }
 
 pub fn sku_name_from_headers(headers: &Headers) -> crate::Result<String> {
-    headers.get_as_string_or_err(&SKU_NAME)
+    headers.get_string(&SKU_NAME)
 }
 
 pub fn account_kind_from_headers(headers: &Headers) -> crate::Result<String> {
-    headers.get_as_string_or_err(&ACCOUNT_KIND)
+    headers.get_string(&ACCOUNT_KIND)
 }
 
 pub fn etag_from_headers_optional(headers: &Headers) -> crate::Result<Option<String>> {
-    Ok(headers.get_as_string(&ETAG))
+    Ok(headers.get_optional_string(&ETAG))
 }
 
 pub fn etag_from_headers(headers: &Headers) -> crate::Result<String> {
-    headers.get_as_string_or_err(&ETAG)
+    headers.get_string(&ETAG)
 }
 
 pub fn lease_time_from_headers(headers: &Headers) -> crate::Result<u8> {
@@ -107,23 +107,23 @@ pub fn sequence_number_from_headers(headers: &Headers) -> crate::Result<u64> {
 }
 
 pub fn session_token_from_headers(headers: &Headers) -> crate::Result<SessionToken> {
-    headers.get_as_string_or_err(&SESSION_TOKEN)
+    headers.get_string(&SESSION_TOKEN)
 }
 
 pub fn server_from_headers(headers: &Headers) -> crate::Result<&str> {
-    headers.get_as_str_or_err(&SERVER)
+    headers.get_str(&SERVER)
 }
 
 pub fn version_from_headers(headers: &Headers) -> crate::Result<&str> {
-    headers.get_as_str_or_err(&VERSION)
+    headers.get_str(&VERSION)
 }
 
 pub fn request_server_encrypted_from_headers(headers: &Headers) -> crate::Result<bool> {
     headers.get_as(&REQUEST_SERVER_ENCRYPTED)
 }
 
 pub fn content_type_from_headers(headers: &Headers) -> crate::Result<&str> {
-    headers.get_as_str_or_err(&CONTENT_TYPE)
+    headers.get_str(&CONTENT_TYPE)
 }
 
 pub fn item_count_from_headers(headers: &Headers) -> crate::Result<u32> {

sdk/core/src/models/etag.rs

@@ -1,5 +1,5 @@
 use serde::{Deserialize, Serialize};
-use std::fmt;
+use std::{fmt, str::FromStr};
 
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 pub struct Etag(String);
@@ -19,6 +19,13 @@ impl AsRef<str> for Etag {
     }
 }
 
+impl FromStr for Etag {
+    type Err = crate::error::Error;
+    fn from_str(s: &str) -> crate::Result<Self> {
+        Ok(Self(s.into()))
+    }
+}
+
 impl fmt::Display for Etag {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         write!(f, "{}", self.0)

sdk/core/src/request_options/next_marker.rs

@@ -32,7 +32,7 @@ impl NextMarker {
     }
 
     pub fn from_header_optional(headers: &Headers) -> crate::Result<Option<Self>> {
-        let header_as_str = headers.get_as_str(&headers::CONTINUATION);
+        let header_as_str = headers.get_optional_str(&headers::CONTINUATION);
 
         Ok(header_as_str
             .filter(|h| !h.is_empty())

sdk/data_cosmos/src/headers/from_headers.rs

@@ -24,24 +24,24 @@ pub(crate) fn activity_id_from_headers(headers: &Headers) -> azure_core::Result<
 }
 
 pub(crate) fn content_path_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&HEADER_CONTENT_PATH)
+    headers.get_str(&HEADER_CONTENT_PATH)
 }
 
 pub(crate) fn alt_content_path_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&HEADER_ALT_CONTENT_PATH)
+    headers.get_str(&HEADER_ALT_CONTENT_PATH)
 }
 
 pub(crate) fn resource_quota_from_headers(
     headers: &Headers,
 ) -> azure_core::Result<Vec<ResourceQuota>> {
-    let s = headers.get_as_str_or_err(&HEADER_RESOURCE_QUOTA)?;
+    let s = headers.get_str(&HEADER_RESOURCE_QUOTA)?;
     resource_quotas_from_str(s)
 }
 
 pub(crate) fn resource_usage_from_headers(
     headers: &Headers,
 ) -> azure_core::Result<Vec<ResourceQuota>> {
-    let s = headers.get_as_str_or_err(&HEADER_RESOURCE_USAGE)?;
+    let s = headers.get_str(&HEADER_RESOURCE_USAGE)?;
     resource_quotas_from_str(s)
 }
 
@@ -104,7 +104,7 @@ pub(crate) fn transport_request_id_from_headers(headers: &Headers) -> azure_core
 }
 
 pub(crate) fn global_committed_lsn_from_headers(headers: &Headers) -> azure_core::Result<u64> {
-    let s = headers.get_as_str_or_err(&HEADER_GLOBAL_COMMITTED_LSN)?;
+    let s = headers.get_str(&HEADER_GLOBAL_COMMITTED_LSN)?;
     Ok(if s == "-1" {
         0
     } else {
@@ -140,23 +140,23 @@ pub(crate) fn current_replica_set_size_from_headers_optional(
 }
 
 pub(crate) fn schema_version_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&HEADER_SCHEMA_VERSION)
+    headers.get_str(&HEADER_SCHEMA_VERSION)
 }
 
 pub(crate) fn server_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&headers::SERVER)
+    headers.get_str(&headers::SERVER)
 }
 
 pub(crate) fn service_version_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&HEADER_SERVICE_VERSION)
+    headers.get_str(&HEADER_SERVICE_VERSION)
 }
 
 pub(crate) fn content_location_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&headers::CONTENT_LOCATION)
+    headers.get_str(&headers::CONTENT_LOCATION)
 }
 
 pub(crate) fn gateway_version_from_headers(headers: &Headers) -> azure_core::Result<&str> {
-    headers.get_as_str_or_err(&HEADER_GATEWAY_VERSION)
+    headers.get_str(&HEADER_GATEWAY_VERSION)
 }
 
 pub(crate) fn max_media_storage_usage_mb_from_headers(
@@ -173,7 +173,7 @@ fn _date_from_headers(
     headers: &Headers,
     header_name: &HeaderName,
 ) -> azure_core::Result<DateTime<Utc>> {
-    let date = headers.get_as_str_or_err(header_name)?;
+    let date = headers.get_str(header_name)?;
     // since Azure returns "GMT" instead of +0000 as timezone we replace it ourselves.
     // For example: Wed, 15 Jan 2020 23:39:44.369 GMT
     let date = date.replace("GMT", "+0000");

sdk/data_tables/src/continuation_next_partition_and_row_key.rs

@@ -19,12 +19,12 @@ impl ContinuationNextPartitionAndRowKey {
     }
 
     pub fn from_header_optional(headers: &Headers) -> azure_core::Result<Option<Self>> {
-        let partition_header_as_str = headers.get_as_str(&HeaderName::from_static(
+        let partition_header_as_str = headers.get_optional_str(&HeaderName::from_static(
             "x-ms-continuation-NextPartitionKey",
         ));
 
         let row_header_as_str =
-            headers.get_as_str(&HeaderName::from_static("x-ms-continuation-NextRowKey"));
+            headers.get_optional_str(&HeaderName::from_static("x-ms-continuation-NextRowKey"));
 
         Ok(partition_header_as_str.filter(|h| !h.is_empty()).map(|h| {
             ContinuationNextPartitionAndRowKey::new(

sdk/data_tables/src/continuation_next_table_name.rs

@@ -17,7 +17,7 @@ impl ContinuationNextTableName {
 
     pub fn from_header_optional(headers: &Headers) -> azure_core::Result<Option<Self>> {
         let header_as_str =
-            headers.get_as_str(&HeaderName::from_static("x-ms-continuation-NextTableName"));
+            headers.get_optional_str(&HeaderName::from_static("x-ms-continuation-NextTableName"));
 
         Ok(header_as_str
             .filter(|h| !h.is_empty())

sdk/data_tables/src/responses/insert_entity_response.rs

@@ -29,7 +29,7 @@ where
     fn try_from(response: CollectedResponse) -> azure_core::Result<Self> {
         let headers = response.headers();
         let entity_with_metadata =
-            match headers.get_as_str_or_err(&HeaderName::from_static("preference-applied"))? {
+            match headers.get_str(&HeaderName::from_static("preference-applied"))? {
                 "return-no-content" => None,
                 "return-content" => Some(response.clone().try_into()?),
                 _ => {

sdk/iot_hub/src/service/responses/query_response.rs

@@ -22,7 +22,7 @@ impl std::convert::TryFrom<crate::service::CollectedResponse> for QueryResponse
         Ok(QueryResponse {
             result: serde_json::from_slice(body)?,
             continuation_token: continuation_token_from_headers_optional(headers)?,
-            item_type: headers.get_as_string_or_err(&headers::ITEM_TYPE)?,
+            item_type: headers.get_string(&headers::ITEM_TYPE)?,
         })
     }
 }