feat: limit functions exposed in indexing status API

common/Cargo.toml

@@ -16,6 +16,7 @@ faux = { version = "0.1.10", optional = true }
 keccak-hash = "0.10.0"
 lazy_static = "1.4.0"
 log = "0.4.20"
+regex = "1.7.1"
 reqwest = "0.11.20"
 secp256k1 = { version = "0.27.0", features = ["recovery"] }
 serde = { version = "1.0.188", features = ["derive"] }

common/src/graphql.rs

@@ -0,0 +1,90 @@
+use std::collections::HashSet;
+
+use regex::Regex;
+
+/// There is no convenient function for filtering GraphQL executable documents
+/// For sake of simplicity, use regex to filter graphql query string
+/// Return original string if the query is okay, otherwise error out with
+/// unsupported fields
+pub fn filter_supported_fields(
+    query: &str,
+    supported_root_fields: &HashSet<&str>,
+) -> Result<String, Vec<String>> {
+    // Create a regex pattern to match the fields not in the supported fields
+    let re = Regex::new(r"\b(\w+)\s*\{").unwrap();
+    let mut unsupported_fields = Vec::new();
+
+    for cap in re.captures_iter(query) {
+        if let Some(match_) = cap.get(1) {
+            let field = match_.as_str();
+            if !supported_root_fields.contains(field) {
+                unsupported_fields.push(field.to_string());
+            }
+        }
+    }
+
+    if !unsupported_fields.is_empty() {
+        return Err(unsupported_fields);
+    }
+
+    Ok(query.to_string())
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_filter_supported_fields_with_valid_fields() {
+        let supported_fields = vec![
+            "indexingStatuses",
+            "publicProofsOfIndexing",
+            "entityChangesInBlock",
+        ]
+        .into_iter()
+        .collect::<HashSet<&str>>();
+
+        let query_string = "{
+            indexingStatuses {
+                subgraph
+                health
+            }
+            publicProofsOfIndexing {
+                number
+            }
+        }";
+
+        assert_eq!(
+            filter_supported_fields(query_string, &supported_fields).unwrap(),
+            query_string.to_string()
+        );
+    }
+
+    #[test]
+    fn test_filter_supported_fields_with_unsupported_fields() {
+        let supported_fields = vec![
+            "indexingStatuses",
+            "publicProofsOfIndexing",
+            "entityChangesInBlock",
+        ]
+        .into_iter()
+        .collect::<HashSet<&str>>();
+
+        let query_string = "{
+            someField {
+                subfield1
+                subfield2
+            }
+            indexingStatuses {
+                subgraph
+                health
+            }
+        }";
+
+        let filtered = filter_supported_fields(query_string, &supported_fields);
+        assert!(filtered.is_err(),);
+        let errors = filtered.err().unwrap();
+        assert_eq!(errors.len(), 1);
+        assert_eq!(errors.first().unwrap(), &String::from("someField"));
+    }
+}

common/src/lib.rs

@@ -3,6 +3,7 @@
 
 pub mod allocations;
 pub mod attestations;
+pub mod graphql;
 pub mod network_subgraph;
 pub mod signature_verification;
 pub mod types;

service/src/query_processor.rs

@@ -55,6 +55,10 @@ pub enum QueryError {
     IndexingError,
     #[error("Bad or invalid entity data found in the subgraph: {}", .0.to_string())]
     BadData(anyhow::Error),
+    #[error("Invalid GraphQL query string: {0}")]
+    InvalidFormat(String),
+    #[error("Cannot query field: {:#?}", .0)]
+    UnsupportedFields(Vec<String>),
     #[error("Unknown error: {0}")]
     Other(anyhow::Error),
 }

service/src/server/routes/status.rs

@@ -1,15 +1,20 @@
 // Copyright 2023-, GraphOps and Semiotic Labs.
 // SPDX-License-Identifier: Apache-2.0
 
+use std::collections::HashSet;
+
 use axum::{
     http::{Request, StatusCode},
     response::IntoResponse,
     Extension, Json,
 };
 
+use hyper::body::Bytes;
+
 use reqwest::{header, Client};
 
 use crate::server::ServerOptions;
+use indexer_common::graphql::filter_supported_fields;
 
 use super::bad_request_response;
 
@@ -18,13 +23,41 @@ pub async fn status_queries(
     Extension(server): Extension<ServerOptions>,
     req: Request<axum::body::Body>,
 ) -> impl IntoResponse {
-    let req_body = req.into_body();
-    // TODO: Extract the incoming GraphQL operation and filter root fields
-    // Pass the modified operation to the actual endpoint
+    fn status_supported_fields() -> HashSet<&'static str> {
+        HashSet::from([
+            "indexingStatuses",
+            "publicProofsOfIndexing",
+            "entityChangesInBlock",
+            "blockData",
+            "cachedEthereumCalls",
+            "subgraphFeatures",
+            "apiVersions",
+        ])
+    }
+
+    let body_bytes = hyper::body::to_bytes(req.into_body()).await.unwrap();
+    // Read the requested query string
+    let query_string = match String::from_utf8(body_bytes.to_vec()) {
+        Ok(s) => s,
+        Err(e) => return bad_request_response(&e.to_string()),
+    };
 
+    // filter supported root fields
+    let query_string = match filter_supported_fields(&query_string, &status_supported_fields()) {
+        Ok(query) => query,
+        Err(unsupported_fields) => {
+            return (
+                StatusCode::BAD_REQUEST,
+                format!("Cannot query field: {:#?}", unsupported_fields),
+            )
+                .into_response();
+        }
+    };
+
+    // Pass the modified operation to the actual endpoint
     let request = Client::new()
         .post(&server.graph_node_status_endpoint)
-        .body(req_body)
+        .body(Bytes::from(query_string))
         .header(header::CONTENT_TYPE, "application/json");
 
     let response: reqwest::Response = match request.send().await {