make progress on instance object creation

src/instance.rs

@@ -1,3 +1,6 @@
+use regex::internal::Inst;
+
+use crate::api::instance;
 use crate::api::schemas::schemas::InstancePoliciesSchema;
 use crate::gateway::Gateway;
 use crate::limit::LimitedRequester;
@@ -11,17 +14,68 @@ use std::fmt;
 The [`Instance`] what you will be using to perform all sorts of actions on the Spacebar server.
  */
 pub struct Instance {
-    urls: URLBundle,
-    instance_info: InstancePoliciesSchema,
-    requester: LimitedRequester,
-    gateway: Gateway,
-    users: HashMap<Token, Username>,
+    pub urls: URLBundle,
+    pub instance_info: InstancePoliciesSchema,
+    pub requester: LimitedRequester,
+    //pub gateway: Gateway,
+    //pub users: HashMap<Token, Username>,
 }
 
 impl Instance {
-    pub fn new() {}
+    /// Creates a new [`Instance`].
+    /// # Arguments
+    /// * `urls` - The [`URLBundle`] that contains all the URLs that are needed to connect to the Spacebar server.
+    /// * `requester` - The [`LimitedRequester`] that will be used to make requests to the Spacebar server.
+    /// # Errors
+    /// * [`InstanceError`] - If the instance cannot be created.
+    pub async fn new(
+        urls: URLBundle,
+        requester: LimitedRequester,
+    ) -> Result<Instance, InstanceError> {
+        let mut instance = Instance {
+            urls,
+            instance_info: InstancePoliciesSchema::new(
+                // This is okay, because the instance_info will be overwritten by the instance_policies_schema() function.
+                "".to_string(),
+                None,
+                None,
+                None,
+                None,
+                None,
+                None,
+                None,
+            ),
+            requester,
+            //gateway: (),
+            //users: (),
+        };
+        instance.instance_info = match instance.instance_policies_schema().await {
+            Ok(schema) => schema,
+            Err(e) => return Err(InstanceError{message: format!("Something seems to be wrong with the instance. Cannot get information about the instance: {}", e)}),
+        };
+        Ok(instance)
+    }
 }
 
+#[derive(Debug, PartialEq, Eq)]
+pub struct InstanceError {
+    pub message: String,
+}
+
+impl InstanceError {
+    fn new(message: String) -> Self {
+        InstanceError { message }
+    }
+}
+
+impl fmt::Display for InstanceError {
+    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+        write!(f, "{}", self.message)
+    }
+}
+
+impl std::error::Error for InstanceError {}
+
 #[derive(Debug, PartialEq, Eq)]
 pub struct Token {
     pub token: String,
@@ -33,6 +87,11 @@ pub struct Username {
 }
 
 impl Username {
+    /// Creates a new [`Username`].
+    /// # Arguments
+    /// * `username` - The username that will be used to create the [`Username`].
+    /// # Errors
+    /// * [`UsernameFormatError`] - If the username is not between 2 and 32 characters.
     pub fn new(username: String) -> Result<Username, UsernameFormatError> {
         if username.len() < 2 || username.len() > 32 {
             return Err(UsernameFormatError::new(