Initial commit: Project structure, Coordinator Server v1.0.0, and Documentation

server/api/coordinator.proto

@@ -0,0 +1,78 @@
+syntax = "proto3";
+
+package coordinator;
+
+option go_package = "server/api";
+
+service Coordinator {
+  // Registers a node. User name is auto-generated by server initially.
+  rpc RegisterNode(RegisterRequest) returns (RegisterResponse);
+
+  // Updates the display name of the node (allows user to change it later).
+  rpc UpdateNodeName(UpdateNameRequest) returns (UpdateNameResponse);
+
+  // Heartbeat to keep the node marked as online in Redis.
+  rpc Heartbeat(HeartbeatRequest) returns (HeartbeatResponse);
+
+  // Requests the connection details for a target peer.
+  rpc GetPeerEndpoint(PeerRequest) returns (PeerResponse);
+
+  // Notifies the coordinator that a node wants to establish a connection.
+  rpc SignalConnection(SignalRequest) returns (SignalResponse);
+}
+
+message RegisterRequest {
+  string network_key = 1;    // The shared secret for this overlay network
+  string node_id = 2;        // Unique hardware/installation ID
+  string public_key = 3;     // WireGuard public key for E2EE
+  string local_ip = 4;       // Local network IP
+}
+
+message RegisterResponse {
+  string virtual_ip = 1;     // Assigned IP in the overlay network
+  string session_token = 2;  // JWT for subsequent authenticated requests
+  string coordinator_address = 3;
+  string assigned_name = 4;    // The auto-generated name (e.g., "Node-8a2f")
+}
+
+message UpdateNameRequest {
+  string node_id = 1;
+  string new_name = 2;
+  string session_token = 3;
+}
+
+message UpdateNameResponse {
+  bool success = 1;
+  string current_name = 2;
+}
+
+message HeartbeatRequest {
+  string node_id = 1;
+  string session_token = 2;
+  string public_endpoint = 3;
+}
+
+message HeartbeatResponse {
+  bool success = 1;
+}
+
+message PeerRequest {
+  string target_node_id = 1;
+  string session_token = 2;
+}
+
+message PeerResponse {
+  string peer_public_key = 1;
+  string public_endpoint = 2;
+  string nat_type = 3;
+}
+
+message SignalRequest {
+  string source_node_id = 1;
+  string target_node_id = 2;
+  string session_token = 3;
+}
+
+message SignalResponse {
+  bool acknowledged = 1;
+}