From ca29121ad9790ee8a9954040db61df8e887089e5 Mon Sep 17 00:00:00 2001
From: mdecimus <mauro@stalw.art>
Date: Tue, 8 Aug 2023 19:21:01 +0200
Subject: [PATCH] Allow custom HTTP headers to be set (#52)

---
 crates/jmap/src/api/config.rs    | 28 +++++++++++++++++++++++++++-
 crates/jmap/src/api/http.rs      | 13 ++++++++++++-
 crates/jmap/src/lib.rs           |  2 ++
 resources/config/jmap.toml       |  3 +++
 tests/resources/test_config.toml |  3 +++
 5 files changed, 47 insertions(+), 2 deletions(-)

diff --git a/crates/jmap/src/api/config.rs b/crates/jmap/src/api/config.rs
index ac25b386..abed3120 100644
--- a/crates/jmap/src/api/config.rs
+++ b/crates/jmap/src/api/config.rs
@@ -21,7 +21,7 @@
  * for more details.
 */
 
-use std::time::Duration;
+use std::{str::FromStr, time::Duration};
 
 use store::{
     fts::Language,
@@ -140,6 +140,32 @@ impl crate::Config {
                 .unwrap_or(true),
             encrypt: settings.property_or_static("jmap.encryption.enable", "true")?,
             encrypt_append: settings.property_or_static("jmap.encryption.append", "false")?,
+            http_headers: settings
+                .values("jmap.http.headers")
+                .map(|(_, v)| {
+                    if let Some((k, v)) = v.split_once(':') {
+                        Ok((
+                            hyper::header::HeaderName::from_str(k.trim()).map_err(|err| {
+                                format!(
+                                    "Invalid header found in property \"jmap.http.headers\": {}",
+                                    err
+                                )
+                            })?,
+                            hyper::header::HeaderValue::from_str(v.trim()).map_err(|err| {
+                                format!(
+                                    "Invalid header found in property \"jmap.http.headers\": {}",
+                                    err
+                                )
+                            })?,
+                        ))
+                    } else {
+                        Err(format!(
+                            "Invalid header found in property \"jmap.http.headers\": {}",
+                            v
+                        ))
+                    }
+                })
+                .collect::<Result<Vec<_>, String>>()?,
         };
         config.add_capabilites(settings);
         Ok(config)
diff --git a/crates/jmap/src/api/http.rs b/crates/jmap/src/api/http.rs
index 2f07c94a..4153b4e1 100644
--- a/crates/jmap/src/api/http.rs
+++ b/crates/jmap/src/api/http.rs
@@ -446,7 +446,18 @@ async fn handle_request<T: AsyncRead + AsyncWrite + Unpin + Send + 'static>(
                         uri = req.uri().to_string(),
                     );
 
-                    let response = parse_jmap_request(jmap, req, session.remote_ip, instance).await;
+                    // Parse JMAP request
+                    let mut response =
+                        parse_jmap_request(jmap.clone(), req, session.remote_ip, instance).await;
+
+                    // Add custom headers
+                    if !jmap.config.http_headers.is_empty() {
+                        let headers = response.headers_mut();
+
+                        for (header, value) in &jmap.config.http_headers {
+                            headers.insert(header.clone(), value.clone());
+                        }
+                    }
 
                     Ok::<_, hyper::Error>(response)
                 }
diff --git a/crates/jmap/src/lib.rs b/crates/jmap/src/lib.rs
index fa297178..c218118d 100644
--- a/crates/jmap/src/lib.rs
+++ b/crates/jmap/src/lib.rs
@@ -150,6 +150,8 @@ pub struct Config {
     pub oauth_expiry_refresh_token_renew: u64,
     pub oauth_max_auth_attempts: u32,
 
+    pub http_headers: Vec<(hyper::header::HeaderName, hyper::header::HeaderValue)>,
+
     pub encrypt: bool,
     pub encrypt_append: bool,
 
diff --git a/resources/config/jmap.toml b/resources/config/jmap.toml
index 6ee03c5d..3759bee5 100644
--- a/resources/config/jmap.toml
+++ b/resources/config/jmap.toml
@@ -36,6 +36,9 @@ timeout = "30s"
 [jmap]
 directory = "__DIRECTORY__"
 
+[jmap.http]
+#headers = ["Access-Control-Allow-Origin: *", "Access-Control-Allow-Methods: POST, GET"]
+
 [jmap.encryption]
 enable = true
 append = false
diff --git a/tests/resources/test_config.toml b/tests/resources/test_config.toml
index c9704cee..1fbfc296 100644
--- a/tests/resources/test_config.toml
+++ b/tests/resources/test_config.toml
@@ -104,6 +104,9 @@ private-key = "file://./tests/resources/tls_privatekey.pem"
 [jmap]
 directory = "local"
 
+[jmap.http]
+headers = ["Access-Control-Allow-Origin: *", "Access-Control-Allow-Methods: POST, GET, HEAD"]
+
 [jmap.protocol]
 set.max-objects = 100000