Limit tab completion of scan command to scans with installed components (#74)

* scans without installed requirements dont tab-complete

* added meets_requirements functions to classes

* updated tests

* added check for None case

pipeline/recon/masscan.py

@@ -14,6 +14,7 @@ from .amass import ParseAmassOutput
 from ..models.port_model import Port
 from ..models.ip_address_model import IPAddress
 
+from .helpers import get_tool_state
 from .config import top_tcp_ports, top_udp_ports, defaults, web_ports
 
 
@@ -63,6 +64,15 @@ class MasscanScan(luigi.Task):
         self.db_mgr = pipeline.models.db_manager.DBManager(db_location=self.db_location)
         self.results_subfolder = (Path(self.results_dir) / "masscan-results").expanduser().resolve()
 
+    @staticmethod
+    def meets_requirements():
+        """ Reports whether or not this scan's needed tool(s) are installed or not """
+        needs = ["masscan"]
+        tools = get_tool_state()
+
+        if tools:
+            return all([tools.get(x).get("installed") is True for x in needs])
+
     def output(self):
         """ Returns the target output for this task.