Do formatting at insert time

migrations/2019-05-01-204240_add_formatted_body_to_gists/down.sql

+ALTER TABLE gists DROP COLUMN formatted_body;

migrations/2019-05-01-204240_add_formatted_body_to_gists/up.sql

+ALTER TABLE gists ADD COLUMN formatted_body TEXT NOT NULL;

src/gists/mod.rs

 use chrono::NaiveDateTime;
 use diesel::pg::PgConnection as PGC;
 use diesel::prelude::*;
+use syntect::highlighting::ThemeSet;
+use syntect::html::highlighted_html_for_string;
+use syntect::parsing::SyntaxSet;
 
 use crate::schema::gists;
 
     pub body: String,
     pub created_at: Option<NaiveDateTime>,
     pub filetype: Option<String>,
+    pub formatted_body: String,
 }
 
 #[derive(Insertable, AsChangeset, Serialize, Deserialize)]
     pub title: String,
     pub body: String,
     pub filetype: Option<String>,
+    pub formatted_body: String,
+}
+
+fn format_gist(filetype: Option<String>, body: String) -> String {
+    filetype.map_or(
+        format!("<pre class='plaintext'>{}</pre>", body),
+        |filetype| {
+            let ps = SyntaxSet::load_defaults_newlines();
+            let ts = ThemeSet::load_defaults();
+            ps.find_syntax_by_extension(&filetype).map_or(
+                format!("<pre class='plaintext'>{}</pre>", body),
+                |syntax| {
+                    highlighted_html_for_string(&body, &ps, syntax, &ts.themes["Solarized (light)"])
+                },
+            )
+        },
+    )
 }
 
 pub fn all(connection: &PGC) -> QueryResult<Vec<Gist>> {
 }
 
 pub fn insert(gist: InsertableGist, connection: &PGC) -> QueryResult<Gist> {
+    let formatted_gist = InsertableGist {
+        filetype: gist.filetype.clone(),
+        title: gist.title,
+        body: gist.body.clone(),
+        formatted_body: format_gist(gist.filetype, gist.body),
+    };
     diesel::insert_into(gists::table)
-        .values(gist)
+        .values(formatted_gist)
         .get_result(connection)
 }

src/routes.rs

 use rocket_contrib::json::Json;
 use rocket_contrib::templates::Template;
 use std::collections::HashMap;
-use syntect::highlighting::ThemeSet;
-use syntect::html::highlighted_html_for_string;
-use syntect::parsing::SyntaxSet;
 
 use crate::connection::DbConn;
 use crate::gists;
     }
 }
 
-fn format_gist(filetype: Option<String>, body: String) -> String {
-    filetype.map_or(
-        format!("<pre class='plaintext'>{}</pre>", body),
-        |filetype| {
-            let ps = SyntaxSet::load_defaults_newlines();
-            let ts = ThemeSet::load_defaults();
-            ps.find_syntax_by_extension(&filetype).map_or(
-                format!("<pre class='plaintext'>{}</pre>", body),
-                |syntax| {
-                    highlighted_html_for_string(&body, &ps, syntax, &ts.themes["Solarized (light)"])
-                },
-            )
-        },
-    )
-}
-
 #[get("/")]
 pub fn index(connection: DbConn) -> Result<Json<Vec<Gist>>, Status> {
     gists::all(&connection)
             String::from("404 - Gist not found"),
             format!("<h3'>{}</h3>", "Gist not found"),
         ),
-        |gist| (gist.title, format_gist(gist.filetype, gist.body)),
+        |gist| (gist.title, gist.formatted_body),
     );
 
     let mut context: HashMap<&str, String> = HashMap::new();

src/schema.rs

         body -> Text,
         created_at -> Nullable<Timestamp>,
         filetype -> Nullable<Varchar>,
+        formatted_body -> Text,
     }
 }