feat: update mustache syntax

README.md

@@ -64,7 +64,7 @@ schema
 
 type Query {
   posts: [Post] @http(path: "/posts")
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User {
@@ -81,7 +81,7 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }
 ```
 

ci-benchmark/benchmark.graphql

@@ -22,5 +22,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

examples/auth.graphql

@@ -9,11 +9,11 @@ schema
 
 type Query {
   posts: [Post] @http(path: "/posts")
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type Mutation {
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User @protected {
@@ -30,5 +30,5 @@ type Post {
   userId: Int!
   title: String!
   body: String! @protected
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

examples/call.graphql

@@ -10,13 +10,13 @@ type Post {
 }
 
 type Query {
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
   firstUser: User @call(steps: [{query: "user", args: {id: 1}}])
-  postFromUser(userId: Int!): [Post] @http(path: "/posts?userId={{args.userId}}")
+  postFromUser(userId: Int!): [Post] @http(path: "/posts?userId={{.args.userId}}")
 }
 
 type User {
   id: Int
   name: String
-  posts: [Post] @call(steps: [{query: "postFromUser", args: {userId: "{{value.id}}"}}])
+  posts: [Post] @call(steps: [{query: "postFromUser", args: {userId: "{{.value.id}}"}}])
 }

examples/graphql-composition.graphql

@@ -17,7 +17,7 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @graphQL(name: "user", args: [{key: "id", value: "{{value.userId}}"}])
+  user: User @graphQL(name: "user", args: [{key: "id", value: "{{.value.userId}}"}])
 }
 
 type User {

examples/grpc.graphql

@@ -8,9 +8,9 @@ schema
 
 type Query {
   news: NewsData! @grpc(method: "news.NewsService.GetAllNews")
-  newsById(news: NewsInput!): News! @grpc(method: "news.NewsService.GetNews", body: "{{args.news}}")
+  newsById(news: NewsInput!): News! @grpc(method: "news.NewsService.GetNews", body: "{{.args.news}}")
   newsByIdBatch(news: NewsInput!): News!
-    @grpc(method: "news.NewsService.GetMultipleNews", body: "{{args.news}}", batchKey: ["news", "id"])
+    @grpc(method: "news.NewsService.GetMultipleNews", body: "{{.args.news}}", batchKey: ["news", "id"])
 }
 
 type News {

examples/jsonplaceholder.graphql

@@ -7,7 +7,7 @@ schema
 type Query {
   posts: [Post] @http(path: "/posts")
   users: [User] @http(path: "/users")
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User {
@@ -24,5 +24,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @call(steps: [{query: "user", args: {id: "{{value.userId}}"}}])
+  user: User @call(steps: [{query: "user", args: {id: "{{.value.userId}}"}}])
 }

examples/jsonplaceholder_batch.graphql

@@ -22,5 +22,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users", query: [{key: "id", value: "{{value.userId}}"}], batchKey: ["id"])
+  user: User @http(path: "/users", query: [{key: "id", value: "{{.value.userId}}"}], batchKey: ["id"])
 }

examples/jsonplaceholder_http_2.graphql

@@ -24,5 +24,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

examples/jsonplaceholder_script.graphql

@@ -7,7 +7,7 @@ schema
 
 type Query {
   posts: [Post] @http(path: "/posts")
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User {
@@ -24,5 +24,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

examples/rest-api.graphql

@@ -8,7 +8,7 @@ schema
 type Query {
   posts: [Post] @http(path: "/posts")
   users: [User] @http(path: "/users")
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User {
@@ -25,5 +25,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @call(steps: [{query: "user", args: {id: "{{value.userId}}"}}])
+  user: User @call(steps: [{query: "user", args: {id: "{{.value.userId}}"}}])
 }

examples/telemetry-otlp.graphql

@@ -9,7 +9,7 @@ schema
         url: "https://api.honeycomb.io:443"
         # gather api key from https://ui.honeycomb.io and set it as env when running tailcall
         headers: [
-          {key: "x-honeycomb-team", value: "{{env.HONEYCOMB_API_KEY}}"}
+          {key: "x-honeycomb-team", value: "{{.env.HONEYCOMB_API_KEY}}"}
           {key: "x-honeycomb-dataset", value: "tailcall"}
         ]
       }
@@ -21,7 +21,7 @@ schema
 
 type Query {
   posts: [Post] @http(path: "/posts") @cache(maxAge: 3000)
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
   users: [User] @http(path: "/users")
   news: NewsData! @grpc(baseURL: "http://localhost:50051", method: "news.NewsService.GetAllNews")
 }
@@ -40,7 +40,7 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }
 
 type News {

examples/telemetry-prometheus.graphql

@@ -7,7 +7,7 @@ schema
 
 type Query {
   posts: [Post] @http(path: "/posts") @cache(maxAge: 5000)
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User {
@@ -24,5 +24,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

examples/telemetry-stdout.graphql

@@ -7,7 +7,7 @@ schema
 
 type Query {
   posts: [Post] @http(path: "/posts") @cache(maxAge: 5000)
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
 }
 
 type User {
@@ -24,5 +24,5 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

src/mustache.rs

@@ -1,3 +1,5 @@
+use std::fmt::Display;
+
 use nom::branch::alt;
 use nom::bytes::complete::{tag, take_until};
 use nom::character::complete::char;
@@ -92,9 +94,9 @@ impl Mustache {
     }
 }
 
-impl ToString for Mustache {
-    fn to_string(&self) -> String {
-        match self {
+impl Display for Mustache {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let str = match self {
             Mustache(segments) => segments
                 .iter()
                 .map(|segment| match segment {
@@ -103,7 +105,8 @@ impl ToString for Mustache {
                 })
                 .collect::<Vec<String>>()
                 .join(""),
-        }
+        };
+        write!(f, "{}", str)
     }
 }
 
@@ -127,8 +130,11 @@ fn parse_expression(input: &str) -> IResult<&str, Segment> {
     delimited(
         tag("{{"),
         map(
-            nom::multi::separated_list1(char('.'), parse_name),
-            Segment::Expression,
+            nom::sequence::tuple((
+                nom::combinator::opt(char('.')), // Optional leading dot
+                nom::multi::separated_list1(char('.'), parse_name),
+            )),
+            |(_, expr_parts)| Segment::Expression(expr_parts),
         ),
         tag("}}"),
     )(input)

tailcall-query-plan/tests/config/user-posts.graphql

@@ -7,8 +7,8 @@ schema
 type Query {
   posts: [Post] @http(path: "/posts")
   users: [User] @http(path: "/users")
-  user(id: Int!): User @http(path: "/users/{{args.id}}")
-  post(id: Int!): Post @http(path: "/posts/{{args.id}}")
+  user(id: Int!): User @http(path: "/users/{{.args.id}}")
+  post(id: Int!): Post @http(path: "/posts/{{.args.id}}")
 }
 
 type User {
@@ -17,13 +17,13 @@ type User {
   username: String!
   email: String!
   phone: String
-  website: String @expr(body: "/users/website/{{value.username}}")
+  website: String @expr(body: "/users/website/{{.value.username}}")
 }
 
 type Post {
   id: Int!
   userId: Int!
   title: String!
   body: String!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }

tests/execution/batching-default.md

@@ -15,7 +15,11 @@ type Post {
   body: String
   userId: Int!
   user: User
-    @http(path: "/users", query: [{key: "id", value: "{{value.userId}}"}, {key: "foo", value: "bar"}], batchKey: ["id"])
+    @http(
+      path: "/users"
+      query: [{key: "id", value: "{{.value.userId}}"}, {key: "foo", value: "bar"}]
+      batchKey: ["id"]
+    )
 }
 
 type User {

tests/execution/batching-disabled.md

@@ -27,7 +27,7 @@
             }
           },
           "http": {
-            "path": "/users/{{args.id}}"
+            "path": "/users/{{.args.id}}"
           },
           "cache": null
         }

tests/execution/batching-group-by-default.md

@@ -17,7 +17,11 @@ type Post {
   body: String
   userId: Int!
   user: User
-    @http(batchKey: ["id"], path: "/users", query: [{key: "id", value: "{{value.userId}}"}, {key: "foo", value: "bar"}])
+    @http(
+      batchKey: ["id"]
+      path: "/users"
+      query: [{key: "id", value: "{{.value.userId}}"}, {key: "foo", value: "bar"}]
+    )
 }
 
 type User {

tests/execution/batching-group-by.md

@@ -17,7 +17,11 @@ type Post {
   body: String
   userId: Int!
   user: User
-    @http(path: "/users", query: [{key: "id", value: "{{value.userId}}"}, {key: "foo", value: "bar"}], batchKey: ["id"])
+    @http(
+      path: "/users"
+      query: [{key: "id", value: "{{.value.userId}}"}, {key: "foo", value: "bar"}]
+      batchKey: ["id"]
+    )
 }
 
 type User {

tests/execution/batching-post.md

@@ -20,7 +20,7 @@ type Post {
   title: String
   body: String
   userId: Int!
-  user: User @http(path: "/users/{{value.userId}}")
+  user: User @http(path: "/users/{{.value.userId}}")
 }
 
 type User {

tests/execution/cache-control.md

@@ -26,7 +26,7 @@
             "query": [
               {
                 "key": "id",
-                "value": "{{args.id}}"
+                "value": "{{.args.id}}"
               }
             ],
             "baseURL": "http://jsonplaceholder.typicode.com"

tests/execution/caching-collision.md

@@ -15,7 +15,7 @@ type Foo {
 
 type Bar {
   id: String!
-  foo: Foo @http(path: "/foo?id={{value.id}}") @cache(maxAge: 300)
+  foo: Foo @http(path: "/foo?id={{.value.id}}") @cache(maxAge: 300)
 }
 ```
 

tests/execution/call-graphql-datasource.md

@@ -10,7 +10,7 @@ schema
 type Query {
   posts: [Post] @http(path: "/posts")
   user(id: Int!): User
-    @graphQL(baseURL: "http://upstream/graphql", name: "user", args: [{key: "id", value: "{{args.id}}"}])
+    @graphQL(baseURL: "http://upstream/graphql", name: "user", args: [{key: "id", value: "{{.args.id}}"}])
 }
 
 type User {
@@ -27,7 +27,7 @@ type Post {
   userId: Int!
   title: String!
   body: String!
-  user: User @call(steps: [{query: "user", args: {id: "{{value.userId}}"}}])
+  user: User @call(steps: [{query: "user", args: {id: "{{.value.userId}}"}}])
 }
 ```