Refactor default headers to be injected dynamically (#367)

crates/yaak-models/migrations/20260119045146_remove-default-workspace-headers.sql

@@ -0,0 +1,12 @@
+-- Filter out headers that match the hardcoded defaults (User-Agent: yaak, Accept: */*),
+-- keeping any other custom headers the user may have added.
+UPDATE workspaces
+SET headers = (
+    SELECT json_group_array(json(value))
+    FROM json_each(headers)
+    WHERE NOT (
+        (LOWER(json_extract(value, '$.name')) = 'user-agent' AND json_extract(value, '$.value') = 'yaak')
+        OR (LOWER(json_extract(value, '$.name')) = 'accept' AND json_extract(value, '$.value') = '*/*')
+    )
+)
+WHERE json_array_length(headers) > 0;

crates/yaak-models/src/queries/grpc_requests.rs

@@ -1,3 +1,4 @@
+use super::dedupe_headers;
 use crate::db_context::DbContext;
 use crate::error::Result;
 use crate::models::{GrpcRequest, GrpcRequestIden, HttpRequestHeader};
@@ -87,6 +88,6 @@ impl<'a> DbContext<'a> {
 
         metadata.append(&mut grpc_request.metadata.clone());
 
-        Ok(metadata)
+        Ok(dedupe_headers(metadata))
     }
 }

crates/yaak-models/src/queries/http_requests.rs

@@ -1,3 +1,4 @@
+use super::dedupe_headers;
 use crate::db_context::DbContext;
 use crate::error::Result;
 use crate::models::{Folder, FolderIden, HttpRequest, HttpRequestHeader, HttpRequestIden};
@@ -87,7 +88,7 @@ impl<'a> DbContext<'a> {
 
         headers.append(&mut http_request.headers.clone());
 
-        Ok(headers)
+        Ok(dedupe_headers(headers))
     }
 
     pub fn list_http_requests_for_folder_recursive(

crates/yaak-models/src/queries/mod.rs

@@ -19,6 +19,26 @@ mod websocket_connections;
 mod websocket_events;
 mod websocket_requests;
 mod workspace_metas;
-mod workspaces;
+pub mod workspaces;
 
 const MAX_HISTORY_ITEMS: usize = 20;
+
+use crate::models::HttpRequestHeader;
+use std::collections::HashMap;
+
+/// Deduplicate headers by name (case-insensitive), keeping the latest (most specific) value.
+/// Preserves the order of first occurrence for each header name.
+pub(crate) fn dedupe_headers(headers: Vec<HttpRequestHeader>) -> Vec<HttpRequestHeader> {
+    let mut index_by_name: HashMap<String, usize> = HashMap::new();
+    let mut deduped: Vec<HttpRequestHeader> = Vec::new();
+    for header in headers {
+        let key = header.name.to_lowercase();
+        if let Some(&idx) = index_by_name.get(&key) {
+            deduped[idx] = header;
+        } else {
+            index_by_name.insert(key, deduped.len());
+            deduped.push(header);
+        }
+    }
+    deduped
+}

crates/yaak-models/src/queries/websocket_requests.rs

@@ -1,3 +1,4 @@
+use super::dedupe_headers;
 use crate::db_context::DbContext;
 use crate::error::Result;
 use crate::models::{HttpRequestHeader, WebsocketRequest, WebsocketRequestIden};
@@ -95,6 +96,6 @@ impl<'a> DbContext<'a> {
 
         headers.append(&mut websocket_request.headers.clone());
 
-        Ok(headers)
+        Ok(dedupe_headers(headers))
     }
 }

crates/yaak-models/src/queries/workspaces.rs

@@ -65,28 +65,7 @@ impl<'a> DbContext<'a> {
     }
 
     pub fn upsert_workspace(&self, w: &Workspace, source: &UpdateSource) -> Result<Workspace> {
-        let mut workspace = w.clone();
-
-        // Add default headers only for NEW workspaces (empty ID means insert, not update)
-        // This prevents re-adding headers if a user intentionally removes all headers
-        if workspace.id.is_empty() && workspace.headers.is_empty() {
-            workspace.headers = vec![
-                HttpRequestHeader {
-                    enabled: true,
-                    name: "User-Agent".to_string(),
-                    value: "yaak".to_string(),
-                    id: None,
-                },
-                HttpRequestHeader {
-                    enabled: true,
-                    name: "Accept".to_string(),
-                    value: "*/*".to_string(),
-                    id: None,
-                },
-            ];
-        }
-
-        self.upsert(&workspace, source)
+        self.upsert(w, source)
     }
 
     pub fn resolve_auth_for_workspace(
@@ -101,6 +80,28 @@ impl<'a> DbContext<'a> {
     }
 
     pub fn resolve_headers_for_workspace(&self, workspace: &Workspace) -> Vec<HttpRequestHeader> {
-        workspace.headers.clone()
+        let mut headers = default_headers();
+        headers.extend(workspace.headers.clone());
+        headers
     }
 }
+
+/// Global default headers that are always sent with requests unless overridden.
+/// These are prepended to the inheritance chain so workspace/folder/request headers
+/// can override or disable them.
+pub fn default_headers() -> Vec<HttpRequestHeader> {
+    vec![
+        HttpRequestHeader {
+            enabled: true,
+            name: "User-Agent".to_string(),
+            value: "yaak".to_string(),
+            id: None,
+        },
+        HttpRequestHeader {
+            enabled: true,
+            name: "Accept".to_string(),
+            value: "*/*".to_string(),
+            id: None,
+        },
+    ]
+}