refactor: add MergeRight derive macro (#1723)

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>
Co-authored-by: Tushar Mathur <[email protected]>

Cargo.toml

@@ -144,6 +144,7 @@ async-graphql = { workspace = true, features = [
 dotenvy = "0.15"
 convert_case = "0.6.0"
 rand = "0.8.5"
+tailcall-macros = { path = "tailcall-macros" }
 tonic-types = "0.11.0"
 
 
@@ -197,6 +198,7 @@ members = [
     "tailcall-autogen",
     "tailcall-aws-lambda",
     "tailcall-cloudflare",
+    "tailcall-macros",
     "tailcall-prettier",
     "tailcall-query-plan",
 ]

src/config/config.rs

@@ -16,11 +16,21 @@ use crate::directive::DirectiveCodec;
 use crate::http::Method;
 use crate::is_default;
 use crate::json::JsonSchema;
+use crate::macros::MergeRight;
 use crate::merge_right::MergeRight;
 use crate::valid::{Valid, Validator};
 
 #[derive(
-    Serialize, Deserialize, Clone, Debug, Default, Setters, PartialEq, Eq, schemars::JsonSchema,
+    Serialize,
+    Deserialize,
+    Clone,
+    Debug,
+    Default,
+    Setters,
+    PartialEq,
+    Eq,
+    schemars::JsonSchema,
+    MergeRight,
 )]
 #[serde(rename_all = "camelCase")]
 pub struct Config {
@@ -154,28 +164,12 @@ impl Config {
     }
 }
 
-impl MergeRight for Config {
-    fn merge_right(self, other: Self) -> Self {
-        let server = self.server.merge_right(other.server);
-        let types = merge_types(self.types, other.types);
-        let unions = merge_unions(self.unions, other.unions);
-        let schema = self.schema.merge_right(other.schema);
-        let upstream = self.upstream.merge_right(other.upstream);
-        let links = merge_links(self.links, other.links);
-        let telemetry = self.telemetry.merge_right(other.telemetry);
-
-        Self { server, upstream, types, schema, unions, links, telemetry }
-    }
-}
-
-fn merge_links(self_links: Vec<Link>, other_links: Vec<Link>) -> Vec<Link> {
-    self_links.merge_right(other_links)
-}
-
 ///
 /// Represents a GraphQL type.
 /// A type can be an object, interface, enum or scalar.
-#[derive(Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema)]
+#[derive(
+    Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema, MergeRight,
+)]
 pub struct Type {
     ///
     /// A map of field name and its definition.
@@ -229,22 +223,9 @@ impl Type {
     }
 }
 
-impl MergeRight for Type {
-    fn merge_right(mut self, other: Self) -> Self {
-        let fields = self.fields.merge_right(other.fields);
-        self.implements = self.implements.merge_right(other.implements);
-        if let Some(ref variants) = self.variants {
-            if let Some(ref other) = other.variants {
-                self.variants = Some(variants.union(other).cloned().collect());
-            }
-        } else {
-            self.variants = other.variants;
-        }
-        Self { fields, ..self }
-    }
-}
-
-#[derive(Clone, Debug, Default, PartialEq, Deserialize, Serialize, Eq, schemars::JsonSchema)]
+#[derive(
+    Clone, Debug, Default, PartialEq, Deserialize, Serialize, Eq, schemars::JsonSchema, MergeRight,
+)]
 #[serde(deny_unknown_fields)]
 /// Used to represent an identifier for a type. Typically used via only by the
 /// configuration generators to provide additional information about the type.
@@ -253,7 +234,7 @@ pub struct Tag {
     pub id: String,
 }
 
-#[derive(Clone, Debug, PartialEq, Deserialize, Serialize, Eq, schemars::JsonSchema)]
+#[derive(Clone, Debug, PartialEq, Deserialize, Serialize, Eq, schemars::JsonSchema, MergeRight)]
 /// The @cache operator enables caching for the query, field or type it is
 /// applied to.
 #[serde(rename_all = "camelCase")]
@@ -264,38 +245,22 @@ pub struct Cache {
     pub max_age: NonZeroU64,
 }
 
-#[derive(Clone, Debug, Deserialize, Serialize, PartialEq, Eq, Default, schemars::JsonSchema)]
+#[derive(
+    Clone, Debug, Deserialize, Serialize, PartialEq, Eq, Default, schemars::JsonSchema, MergeRight,
+)]
 pub struct Protected {}
 
-fn merge_types(
-    mut self_types: BTreeMap<String, Type>,
-    other_types: BTreeMap<String, Type>,
-) -> BTreeMap<String, Type> {
-    for (name, mut other_type) in other_types {
-        if let Some(self_type) = self_types.remove(&name) {
-            other_type = self_type.merge_right(other_type);
-        }
-
-        self_types.insert(name, other_type);
-    }
-    self_types
-}
-
-fn merge_unions(
-    mut self_unions: BTreeMap<String, Union>,
-    other_unions: BTreeMap<String, Union>,
-) -> BTreeMap<String, Union> {
-    for (name, mut other_union) in other_unions {
-        if let Some(self_union) = self_unions.remove(&name) {
-            other_union = self_union.merge_right(other_union);
-        }
-        self_unions.insert(name, other_union);
-    }
-    self_unions
-}
-
 #[derive(
-    Serialize, Deserialize, Clone, Debug, Default, Setters, PartialEq, Eq, schemars::JsonSchema,
+    Serialize,
+    Deserialize,
+    Clone,
+    Debug,
+    Default,
+    Setters,
+    PartialEq,
+    Eq,
+    schemars::JsonSchema,
+    MergeRight,
 )]
 #[setters(strip_option)]
 pub struct RootSchema {
@@ -306,17 +271,6 @@ pub struct RootSchema {
     pub subscription: Option<String>,
 }
 
-impl MergeRight for RootSchema {
-    // TODO: add unit-tests
-    fn merge_right(self, other: Self) -> Self {
-        Self {
-            query: self.query.merge_right(other.query),
-            mutation: self.mutation.merge_right(other.mutation),
-            subscription: self.subscription.merge_right(other.subscription),
-        }
-    }
-}
-
 #[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq, schemars::JsonSchema)]
 #[serde(deny_unknown_fields)]
 /// Used to omit a field from public consumption.
@@ -409,6 +363,13 @@ pub struct Field {
     pub protected: Option<Protected>,
 }
 
+// It's a terminal implementation of MergeRight
+impl MergeRight for Field {
+    fn merge_right(self, other: Self) -> Self {
+        other
+    }
+}
+
 impl Field {
     pub fn has_resolver(&self) -> bool {
         self.http.is_some()
@@ -522,19 +483,12 @@ pub struct Arg {
     pub default_value: Option<Value>,
 }
 
-#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq, schemars::JsonSchema)]
+#[derive(Serialize, Deserialize, Clone, Debug, PartialEq, Eq, schemars::JsonSchema, MergeRight)]
 pub struct Union {
     pub types: BTreeSet<String>,
     pub doc: Option<String>,
 }
 
-impl MergeRight for Union {
-    fn merge_right(mut self, other: Self) -> Self {
-        self.types = self.types.merge_right(other.types);
-        self
-    }
-}
-
 #[derive(Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema)]
 #[serde(deny_unknown_fields)]
 /// The @http operator indicates that a field or node is backed by a REST API.

src/config/config_module.rs

@@ -9,13 +9,14 @@ use rustls_pki_types::{CertificateDer, PrivateKeyDer};
 
 use crate::blueprint::GrpcMethod;
 use crate::config::Config;
+use crate::macros::MergeRight;
 use crate::merge_right::MergeRight;
 use crate::rest::{EndpointSet, Unchecked};
 use crate::scalar;
 
 /// A wrapper on top of Config that contains all the resolved extensions and
 /// computed values.
-#[derive(Clone, Debug, Default, Setters)]
+#[derive(Clone, Debug, Default, Setters, MergeRight)]
 pub struct ConfigModule {
     pub config: Config,
     pub extensions: Extensions,
@@ -39,7 +40,7 @@ impl<A> Deref for Content<A> {
 /// Extensions are meta-information required before we can generate the
 /// blueprint. Typically, this information cannot be inferred without performing
 /// an IO operation, i.e., reading a file, making an HTTP call, etc.
-#[derive(Clone, Debug, Default)]
+#[derive(Clone, Debug, Default, MergeRight)]
 pub struct Extensions {
     /// Contains the file descriptor sets resolved from the links
     pub grpc_file_descriptors: Vec<Content<FileDescriptorSet>>,
@@ -79,35 +80,6 @@ impl Extensions {
     }
 }
 
-impl MergeRight for Extensions {
-    fn merge_right(mut self, mut other: Self) -> Self {
-        self.grpc_file_descriptors = self
-            .grpc_file_descriptors
-            .merge_right(other.grpc_file_descriptors);
-        self.script = self.script.merge_right(other.script.take());
-        self.cert = self.cert.merge_right(other.cert);
-        self.keys = if !other.keys.is_empty() {
-            other.keys
-        } else {
-            self.keys
-        };
-        self.endpoint_set = self.endpoint_set.merge_right(other.endpoint_set);
-        self.htpasswd = self.htpasswd.merge_right(other.htpasswd);
-        self.jwks = self.jwks.merge_right(other.jwks);
-        self
-    }
-}
-
-impl MergeRight for ConfigModule {
-    fn merge_right(mut self, other: Self) -> Self {
-        self.config = self.config.merge_right(other.config);
-        self.extensions = self.extensions.merge_right(other.extensions);
-        self.input_types = self.input_types.merge_right(other.input_types);
-        self.output_types = self.output_types.merge_right(other.output_types);
-        self
-    }
-}
-
 impl Deref for ConfigModule {
     type Target = Config;
     fn deref(&self) -> &Self::Target {

src/config/cors.rs

@@ -3,9 +3,13 @@ use serde::{Deserialize, Serialize};
 
 use crate::http::Method;
 use crate::is_default;
+use crate::macros::MergeRight;
+use crate::merge_right::MergeRight;
 
 /// Type to configure Cross-Origin Resource Sharing (CORS) for a server.
-#[derive(Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema)]
+#[derive(
+    Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema, MergeRight,
+)]
 #[serde(rename_all = "camelCase")]
 pub struct Cors {
     /// Indicates whether the server allows credentials (e.g., cookies,

src/config/headers.rs

@@ -5,8 +5,12 @@ use serde::{Deserialize, Serialize};
 use crate::config::cors::Cors;
 use crate::config::KeyValue;
 use crate::is_default;
+use crate::macros::MergeRight;
+use crate::merge_right::MergeRight;
 
-#[derive(Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema)]
+#[derive(
+    Serialize, Deserialize, Clone, Debug, Default, PartialEq, Eq, schemars::JsonSchema, MergeRight,
+)]
 #[serde(rename_all = "camelCase")]
 pub struct Headers {
     #[serde(default, skip_serializing_if = "is_default")]
@@ -47,21 +51,3 @@ impl Headers {
         self.cors.clone()
     }
 }
-
-pub fn merge_headers(current: Option<Headers>, other: Option<Headers>) -> Option<Headers> {
-    let mut headers = current.clone();
-
-    if let Some(other_headers) = other {
-        if let Some(mut self_headers) = current.clone() {
-            self_headers.cache_control = other_headers.cache_control.or(self_headers.cache_control);
-            self_headers.custom.extend(other_headers.custom);
-            self_headers.cors = other_headers.cors.or(self_headers.cors);
-
-            headers = Some(self_headers);
-        } else {
-            headers = Some(other_headers);
-        }
-    }
-
-    headers
-}