Support Serde Serialize struct when inserting

Cargo.toml

@@ -13,6 +13,8 @@ edition = "2018"
 
 [dependencies]
 reqwest = { version = "0.11", features = ["json"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
 
 [dev-dependencies]
 json = "0.12"

README.md

@@ -13,7 +13,7 @@ Add this to your `Cargo.toml`:
 
 ```toml
 [dependencies]
-postgrest = "1.0"
+postgrest = "1.1.1"
 ```
 
 Simple example:
@@ -74,7 +74,7 @@ let body = resp
 use postgrest::Postgrest;
 use dotenv;
 
-dotenv::dotenv().ok(); 
+dotenv::dotenv().ok();
 
 let client = Postgrest::new("https://your.supabase.endpoint/rest/v1/")
     .insert_header(
@@ -92,7 +92,7 @@ let body = resp
 
 ### Building Queries
 
-These examples assume you've already initialized the client.  The methods `.from()` and `.rpc()` initalizes the query builder inside the client.
+These examples assume you've already initialized the client. The methods `.from()` and `.rpc()` initalizes the query builder inside the client.
 
 Using filters:
 

src/builder.rs

@@ -2,6 +2,7 @@ use reqwest::{
     header::{HeaderMap, HeaderValue},
     Client, Error, Method, Response,
 };
+use serde::Serialize;
 
 /// QueryBuilder struct
 pub struct Builder<'a> {
@@ -337,6 +338,15 @@ impl<'a> Builder<'a> {
         self
     }
 
+    pub fn insert_json<T>(mut self, body: T) -> Self
+    where T: Serialize, {
+        self.method = Method::POST;
+        self.headers
+            .insert("Prefer", HeaderValue::from_static("return=representation"));
+        self.body = Some(serde_json::to_string(&body).unwrap());
+        self
+    }
+
     /// Performs an upsert of the `body` (in JSON) into the table.
     ///
     /// # Note

tests/client.rs

@@ -1,6 +1,7 @@
 use postgrest::Postgrest;
 
 use std::error::Error;
+use serde::Serialize;
 
 const REST_URL: &str = "http://localhost:3000";
 
@@ -54,6 +55,33 @@ async fn insert() -> Result<(), Box<dyn Error>> {
     Ok(())
 }
 
+#[derive(Serialize)]
+struct Message {
+    message: String,
+    channel_id: u16,
+    username: String
+}
+
+#[tokio::test]
+async fn insert_json() -> Result<(), Box<dyn Error>> {
+    let client = Postgrest::new(REST_URL);
+    let fake_message = Message {
+        message: "Test message 0".to_string(),
+        channel_id: 1,
+        username: "kiwicopple".to_string()
+    };
+    let resp = client
+        .from("messages")
+        .insert_json(&fake_message)
+        .execute()
+        .await?;
+    let status = resp.status();
+
+    assert_eq!(status.as_u16(), 201);
+
+    Ok(())
+}
+
 #[tokio::test]
 async fn upsert() -> Result<(), Box<dyn Error>> {
     let client = Postgrest::new(REST_URL);