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src/session.rs

@@ -40,16 +40,33 @@ pub struct SessionCredentials {
     pub authorization: Vec<FieldElement>,
 }
 
-/// Retrieves the session for the given chain id.
-pub fn get(chain_id: FieldElement) -> anyhow::Result<SessionDetails> {
+/// Retrieves the session for the given chain id of the currently authenticated user.
+/// Returns `None` if no session can be found for the chain id.
+///
+/// # Errors
+///
+/// This function will return an error if there is no authenticated user.
+///
+pub fn get(chain_id: FieldElement) -> anyhow::Result<Option<SessionDetails>> {
     let credentials = Credentials::load()?;
     let username = credentials.account.expect("id must exist").id;
-    let contents = fs::read_to_string(get_file_path(&username, chain_id))?;
-    Ok(serde_json::from_str(&contents)?)
+    let path = get_file_path(&username, chain_id);
+
+    if path.exists() {
+        let contents = fs::read_to_string(path)?;
+        Ok(Some(serde_json::from_str(&contents)?))
+    } else {
+        Ok(None)
+    }
 }
 
-/// Stores the session on-disk.
-pub fn store(chain_id: FieldElement, session: &SessionDetails) -> anyhow::Result<()> {
+/// Stores the session on-disk. Returns the path to the file where the `session` has been written to.
+///
+/// # Errors
+///
+/// This function will return an error if there is no authenticated user.
+///
+pub fn store(chain_id: FieldElement, session: &SessionDetails) -> anyhow::Result<PathBuf> {
     // TODO: maybe can store the authenticated user in a global variable so that
     // we don't have to call load again if we already did it before.
     let credentials = Credentials::load()?;
@@ -59,18 +76,23 @@ pub fn store(chain_id: FieldElement, session: &SessionDetails) -> anyhow::Result
     // Create the parent directories if they don't yet exist.
     if let Some(parent) = path.parent() {
         if !parent.exists() {
-            trace!(path = %parent.display(), "Creating parent directories.");
             fs::create_dir_all(&path)?;
         }
     }
 
     let contents = serde_json::to_string_pretty(session)?;
     fs::write(&path, contents)?;
-    trace!(path = %path.display(), "Session token stored successfully.");
 
-    Ok(())
+    Ok(path)
 }
 
+/// Creates a new session token. This will open a browser to the Cartridge Controller keychain page
+/// to prompt user to create a new session for the given policies and network.
+///
+/// # Errors
+///
+/// This function will return an error if there is no authenticated user.
+///
 #[tracing::instrument(level = "trace", skip(rpc_url), fields(policies = policies.len()))]
 pub async fn create<U>(rpc_url: U, policies: &[Policy]) -> anyhow::Result<SessionDetails>
 where