feat: create a server function for creating a task

src/server/mod.rs

@@ -1,2 +1,3 @@
 mod database_connection;
 pub(crate) mod projects;
+pub(crate) mod tasks;

src/server/tasks.rs

@@ -0,0 +1,30 @@
+use crate::errors::error::Error;
+use crate::errors::error_vec::ErrorVec;
+use crate::models::task::{NewTask, Task};
+use crate::server::database_connection::establish_database_connection;
+use diesel::{RunQueryDsl, SelectableHelper};
+use dioxus::prelude::*;
+use validator::Validate;
+use crate::errors::task_create_error::TaskCreateError;
+
+#[server]
+pub(crate) async fn create_task(new_task: NewTask)
+                                -> Result<Task, ServerFnError<ErrorVec<TaskCreateError>>> {
+    use crate::schema::tasks;
+
+    new_task.validate()
+        .map_err::<ErrorVec<TaskCreateError>, _>(|errors| errors.into())?;
+
+    let mut connection = establish_database_connection()
+        .map_err::<ErrorVec<TaskCreateError>, _>(
+            |_| vec![TaskCreateError::Error(Error::ServerInternal)].into()
+        )?;
+
+    let new_task = diesel::insert_into(tasks::table)
+        .values(&new_task)
+        .returning(Task::as_returning())
+        .get_result(&mut connection)
+        .unwrap();
+
+    Ok(new_task)
+}