Implement the --output option for schema introspection

Author: tomhoule

graphql_client_cli/src/main.rs

@@ -60,8 +60,12 @@ fn main() -> Result<(), failure::Error> {
 fn introspect_schema(location: String, output: Option<PathBuf>) -> Result<(), failure::Error> {
     use reqwest::header::*;
     use reqwest::mime;
+    use std::io::Write;
 
-    // let dest_file = ::std::fs::File::open(&output)?;
+    let mut out: Box<Write> = match output {
+        Some(path) => Box::new(::std::fs::File::create(path)?),
+        None => Box::new(::std::io::stdout()),
+    };
 
     let request_body: graphql_client::GraphQLQueryBody<()> = graphql_client::GraphQLQueryBody {
         variables: (),
@@ -83,8 +87,9 @@ fn introspect_schema(location: String, output: Option<PathBuf>) -> Result<(), fa
     }
 
     let json: graphql_client::GraphQLResponse<introspection_query::ResponseData> = res.json()?;
+    let json = serde_json::to_string(&json)?;
 
-    println!("{:?}", json);
+    write!(out, "{}", json)?;
 
     Ok(())
 }

graphql_query_derive/src/fragments.rs

@@ -19,7 +19,7 @@ impl GqlFragment {
         let fields = object.response_fields_for_selection(context, &self.selection, &self.name);
 
         quote!{
-            #[derive(Debug, Deserialize)]
+            #[derive(Debug, Deserialize, Serialize)]
             pub struct #name_ident {
                 #(#fields,)*
             }

graphql_query_derive/src/objects.rs

@@ -31,7 +31,7 @@ impl GqlObject {
         Ok(quote! {
             #(#field_impls)*
 
-            #[derive(Debug, Deserialize)]
+            #[derive(Debug, Serialize, Deserialize)]
             pub struct #name {
                 #(#fields,)*
             }

graphql_query_derive/src/schema.rs

@@ -169,7 +169,7 @@ impl Schema {
 
             #variables_struct
 
-            #[derive(Debug, Deserialize)]
+            #[derive(Debug, Serialize, Deserialize)]
             pub struct ResponseData {
                 #(#response_data_fields)*,
             }