Add ready_log_line (#67)

Author: greg-hellings

CHANGELOG.md

@@ -11,6 +11,7 @@
       - ~~#54: Add `apiServer` option to control REST API server~~
       - $60: Add `httpServer.{enable, port, uds}` options to control the HTTP server.
       - #56: Add `preHook` and `postHook` for running commands before and after launching process-compose respectively.
+      - #67: Add `ready_log_line`
 - Notable changes
     - #58: Obviate IFD by switching to JSON config
 - Fixes

nix/process-compose/settings/process.nix

@@ -28,6 +28,7 @@ in
               "process_completed"
               "process_completed_successfully"
               "process_healthy"
+              "process_log_ready"
               "process_started"
             ];
             example = "process_healthy";
@@ -133,6 +134,17 @@ in
         The settings used to check if the process is alive.
       '';
     };
+    ready_log_line = mkOption {
+      type = types.nullOr types.str;
+      default = null;
+      example = "process is ready";
+      description = ''
+        A string to search for in the output of the command that indicates
+        the process is ready. String will be part of a regex '.*{ready_log_line}.*'.
+        This should be used for long running processes that do not have a
+        readily accessible check for http or similar other checks.
+      '';
+    };
 
     namespace = mkOption {
       type = types.str;