Add Content-Type to finalize request in KV client

[pavelm10]

Fixes #1146

[bmc-msft]

This appears to be a larger problem than just SetSecretBuilder. Setting the content type was mistakenly dropped in #962.

Instead of updating just SetSecretBuilder, can you instead update finalize_request?

Perhaps something like this:

--- a/sdk/security_keyvault/src/clients/keyvault_client.rs
+++ b/sdk/security_keyvault/src/clients/keyvault_client.rs
@@ -4,7 +4,8 @@ use azure_core::{
     date,
     error::{Error, ErrorKind},
     headers::*,
-    Body, Context, Method, Pipeline, Request, Response,
+    prelude::*,
+    Body, Method, Pipeline, Request, Response,
 };
 use const_format::formatcp;
 use std::sync::Arc;
@@ -84,6 +85,9 @@ impl KeyvaultClient {
         request.insert_header(MS_DATE, time);

         if let Some(request_body) = request_body {
+            if request.headers().get_optional_str(&CONTENT_TYPE).is_none() {
+                request.insert_headers(&ContentType::APPLICATION_JSON);
+            }
             request.insert_header(CONTENT_LENGTH, request_body.len().to_string());
             request.set_body(request_body);
         } else {

[bmc-msft]

Note, if you'd prefer, let me know and I can make the broader change.

Thanks!

[pavelm10]

I can do it, I was just thinking that the other operations (get, delete, get_versions) are working without the Content-Type header, hence putting it into the common finalize_request method seemed incorrect to me.

[pavelm10]

but your suggestion make sense that for request with body it should be added, in case in the future there are other operation which need to set the header. I will change it according to your suggestion.

[bmc-msft]

get & delete do not set request bodies, which makes this less of an issue.

[bmc-msft]

Thanks for the PR!

[pavelm10]

No problem