feat(plugins): add SubsonicAPI CallRaw, with support for raw=true binary response for host functions (#4982)

* feat: implement raw binary framing for host function responses Signed-off-by: Deluan <deluan@navidrome.org> * feat: add CallRaw method for Subsonic API to handle binary responses Signed-off-by: Deluan <deluan@navidrome.org> * test: add tests for raw=true methods and binary framing generation Signed-off-by: Deluan <deluan@navidrome.org> * fix: improve error message for malformed raw responses to indicate incomplete header Signed-off-by: Deluan <deluan@navidrome.org> * fix: add wasm_import_module attribute for raw methods and improve content-type handling Signed-off-by: Deluan <deluan@navidrome.org> --------- Signed-off-by: Deluan <deluan@navidrome.org>
2026-02-04 15:48:08 -05:00
parent 19ea338bed
commit e8863ed147
23 changed files with 1223 additions and 40 deletions
@@ -33,6 +33,7 @@ struct {{requestType .}} {
 {{- end}}
 }
 {{- end}}
+{{- if not .Raw}}

 #[derive(Debug, Clone, Deserialize)]
 #[serde(rename_all = "camelCase")]
@@ -47,16 +48,92 @@ struct {{responseType .}} {
 {{- end}}
 }
 {{- end}}
+{{- end}}

 #[host_fn]
 extern "ExtismHost" {
 {{- range .Service.Methods}}
+{{- if not .Raw}}
    fn {{exportName .}}(input: Json<{{if .HasParams}}{{requestType .}}{{else}}serde_json::Value{{end}}>) -> Json<{{responseType .}}>;
 {{- end}}
+{{- end}}
 }
+{{- /* Declare raw extern "C" imports for raw methods */ -}}
+{{- range .Service.Methods}}
+{{- if .Raw}}
+
+#[link(wasm_import_module = "extism:host/user")]
+extern "C" {
+    fn {{exportName .}}(offset: u64) -> u64;
+}
+{{- end}}
+{{- end}}

 {{- /* Generate wrapper functions */ -}}
 {{range .Service.Methods}}
+{{- if .Raw}}
+
+{{if .Doc}}{{rustDocComment .Doc}}{{else}}/// Calls the {{exportName .}} host function.{{end}}
+{{- if .HasParams}}
+///
+/// # Arguments
+{{- range .Params}}
+/// * `{{.RustName}}` - {{rustType .}} parameter.
+{{- end}}
+{{- end}}
+///
+/// # Returns
+/// A tuple of (content_type, data) with the raw binary response.
+///
+/// # Errors
+/// Returns an error if the host function call fails.
+pub fn {{rustFunc .}}({{range $i, $p := .Params}}{{if $i}}, {{end}}{{$p.RustName}}: {{rustParamType $p}}{{end}}) -> Result<(String, Vec<u8>), Error> {
+{{- if .HasParams}}
+    let req = {{requestType .}} {
+{{- range .Params}}
+        {{.RustName}}: {{.RustName}}{{if .NeedsToOwned}}.to_owned(){{end}},
+{{- end}}
+    };
+    let input_bytes = serde_json::to_vec(&req).map_err(|e| Error::msg(e.to_string()))?;
+{{- else}}
+    let input_bytes = b"{}".to_vec();
+{{- end}}
+    let input_mem = Memory::from_bytes(&input_bytes).map_err(|e| Error::msg(e.to_string()))?;
+
+    let response_offset = unsafe { {{exportName .}}(input_mem.offset()) };
+
+    let response_mem = Memory::find(response_offset)
+        .ok_or_else(|| Error::msg("empty response from host"))?;
+    let response_bytes = response_mem.to_vec();
+
+    if response_bytes.is_empty() {
+        return Err(Error::msg("empty response from host"));
+    }
+    if response_bytes[0] == 0x01 {
+        let msg = String::from_utf8_lossy(&response_bytes[1..]).to_string();
+        return Err(Error::msg(msg));
+    }
+    if response_bytes[0] != 0x00 {
+        return Err(Error::msg("unknown response status"));
+    }
+    if response_bytes.len() < 5 {
+        return Err(Error::msg("malformed raw response: incomplete header"));
+    }
+    let ct_len = u32::from_be_bytes([
+        response_bytes[1],
+        response_bytes[2],
+        response_bytes[3],
+        response_bytes[4],
+    ]) as usize;
+    if ct_len > response_bytes.len() - 5 {
+        return Err(Error::msg("malformed raw response: content-type overflow"));
+    }
+    let ct_end = 5 + ct_len;
+    let content_type = String::from_utf8_lossy(&response_bytes[5..ct_end]).to_string();
+    let data = response_bytes[ct_end..].to_vec();
+    Ok((content_type, data))
+}
+{{- else}}

 {{if .Doc}}{{rustDocComment .Doc}}{{else}}/// Calls the {{exportName .}} host function.{{end}}
 {{- if .HasParams}}
@@ -132,3 +209,4 @@ pub fn {{rustFunc .}}({{range $i, $p := .Params}}{{if $i}}, {{end}}{{$p.RustName
 }
 {{- end}}
 {{- end}}
+{{- end}}