spindle: allowing configuring queue size and max job count

Signed-off-by: oppiliappan <[e-mail]>

nix/modules/spindle.nix

···
             description = "DID of owner (required)";
           };
 
+          maxJobCount = mkOption {
+            type = types.int;
+            default = 2;
+            example = 5;
+            description = "Maximum number of concurrent jobs to run";
+          };
+
+          queueSize = mkOption {
+            type = types.int;
+            default = 100;
+            example = 100;
+            description = "Maximum number of jobs queue up";
+          };
+
           secrets = {
             provider = mkOption {
               type = types.str;
···
             "SPINDLE_SERVER_JETSTREAM=${cfg.server.jetstreamEndpoint}"
             "SPINDLE_SERVER_DEV=${lib.boolToString cfg.server.dev}"
             "SPINDLE_SERVER_OWNER=${cfg.server.owner}"
+            "SPINDLE_SERVER_MAX_JOB_COUNT=${toString cfg.server.maxJobCount}"
+            "SPINDLE_SERVER_QUEUE_SIZE=${toString cfg.server.queueSize}"
             "SPINDLE_SERVER_SECRETS_PROVIDER=${cfg.server.secrets.provider}"
             "SPINDLE_SERVER_SECRETS_OPENBAO_PROXY_ADDR=${cfg.server.secrets.openbao.proxyAddr}"
             "SPINDLE_SERVER_SECRETS_OPENBAO_MOUNT=${cfg.server.secrets.openbao.mount}"

nix/vm.nix

···
             hostname = "localhost:6555";
             listenAddr = "0.0.0.0:6555";
             dev = true;
+            queueSize = 100;
+            maxJobCount = 2;
             secrets = {
               provider = "sqlite";
             };

spindle/config/config.go

···
 	Owner             string  `env:"OWNER, required"`
 	Secrets           Secrets `env:",prefix=SECRETS_"`
 	LogDir            string  `env:"LOG_DIR, default=/var/log/spindle"`
+	QueueSize         int     `env:"QUEUE_SIZE, default=100"`
+	MaxJobCount       int     `env:"MAX_JOB_COUNT, default=2"` // max number of jobs that run at a time
 }
 
 func (s Server) Did() syntax.DID {

spindle/server.go

···
 		return err
 	}
 
-	jq := queue.NewQueue(100, 5)
+	jq := queue.NewQueue(cfg.Server.QueueSize, cfg.Server.MaxJobCount)
+	logger.Info("initialized queue", "queueSize", cfg.Server.QueueSize, "numWorkers", cfg.Server.MaxJobCount)
 
 	collections := []string{
 		tangled.SpindleMemberNSID,