Dynamic GraphQL API

aquadoggo/Cargo.toml

@@ -15,6 +15,7 @@ edition = "2018"
 
 [dependencies]
 anyhow = "1.0.43"
+apollo-parser = "0.2.1"
 async-graphql = "3.0.25"
 async-graphql-tide = "3.0.25"
 async-std = { version = "1.10.0", features = ["attributes"] }
@@ -34,6 +35,7 @@ openssl-probe = "0.1.4"
 # @TODO: Move this back to crate as soon as upcoming changes have been published
 p2panda-rs = { git = "https://github.com/p2panda/p2panda", branch = "document" }
 rand = "0.8.4"
+sea-query = "0.20.0"
 serde = { version = "1.0.130", features = ["derive"] }
 serde_json = "1.0.67"
 sqlformat = "0.1.7"

aquadoggo/src/graphql/api.rs

@@ -5,6 +5,7 @@ use async_graphql::{EmptyMutation, EmptySubscription, Schema};
 use tide::{http::mime, Body, Response, StatusCode};
 
 use crate::db::Pool;
+use crate::graphql::convert::gql_to_sql;
 use crate::graphql::QueryRoot;
 use crate::server::{ApiRequest, ApiResult, ApiState};
 
@@ -56,7 +57,11 @@ impl tide::Endpoint<ApiState> for Endpoint {
     ///
     /// This handler resolves all incoming GraphQL requests and answers them both for dynamically
     /// and statically generated schemas.
-    async fn call(&self, request: ApiRequest) -> ApiResult {
+    async fn call(&self, mut request: ApiRequest) -> ApiResult {
+        let graphql_request = request.body_json::<async_graphql::Request>().await?;
+        let sql = gql_to_sql(&graphql_request.query).unwrap();
+        println!("{:?}", sql);
+
         // @TODO: Implement handling of dynamic GraphQL requests. Route all GraphQL requests to
         // static handler for now.
         self.static_endpoint.call(request).await

aquadoggo/src/graphql/convert/mod.rs

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: AGPL-3.0-or-later
+
+mod query;
+mod schema;
+mod sql;
+
+pub use query::{AbstractQuery, AbstractQueryError, Argument, Field, MetaField};
+pub use schema::{Schema, SchemaParseError};
+pub use sql::query_to_sql;
+
+pub fn gql_to_sql(query: &str) -> anyhow::Result<String> {
+    // Convert GraphQL query to our own abstract query representation
+    let root = AbstractQuery::new(query)?;
+
+    // Convert to SQL query
+    let sql = query_to_sql(root).unwrap();
+
+    Ok(sql)
+}
+
+#[cfg(test)]
+mod tests {
+    use super::gql_to_sql;
+
+    #[test]
+    fn parser() {
+        let query = "{
+            festival_events_0020c65567ae37efea293e34a9c7d13f8f2bf23dbdc3b5c7b9ab46293111c48fc78b(document: \"0020b177ec1bf26dfb3b7010d473e6d44713b29b765b99c6e60ecbfae742de496543\") {
+                document
+                fields {
+                    title
+                    description
+                }
+            }
+        }";
+
+        let sql = gql_to_sql(query).unwrap();
+
+        assert_eq!(
+            sql,
+            "SELECT \"title\", \"description\", \"document\" FROM \"festival_events_0020c65567ae37efea293e34a9c7d13f8f2bf23dbdc3b5c7b9ab46293111c48fc78b\" WHERE \"document\" = '0020b177ec1bf26dfb3b7010d473e6d44713b29b765b99c6e60ecbfae742de496543'"
+        );
+    }
+}