PiSrf: Added decimal places option + stop bugfix + more keywords (#816)

* Added decimal places option + bugfix + keywords

Added option to output more decimal places. When no decimal places are configured output stays the same for full backward compatibility.

Fixed bug that on restart flows error "Error stopping node: Close timed out" occured. Also removed sudo, because no need to run code with root rights. On systems where you need password for sudo it wouldn't run then. 

Added Keywords for "HC-SR04" and "SR04", because this module is fully compatible with this node.

* Added decimal places option + bugfix + keywords

Added option to output more decimal places. When no decimal places are configured output stays the same for full backward compatibility.

Fixed bug that on restart flows error "Error stopping node: Close timed out" occured. Also removed sudo, because no need to run code with root rights. On systems where you need password for sudo it wouldn't run then. 

Added Keywords for "HC-SR04" and "SR04", because this module is fully compatible with this node.

* Added decimal places option + bugfix + keywords

Added option to output more decimal places. When no decimal places are configured output stays the same for full backward compatibility.

Fixed bug that on restart flows error "Error stopping node: Close timed out" occured. Also removed sudo, because no need to run code with root rights. On systems where you need password for sudo it wouldn't run then. 

Added Keywords for "HC-SR04" and "SR04", because this module is fully compatible with this node.

hardware/PiSrf/nrsrf

@@ -4,4 +4,4 @@ python_cmd='python3'
 command -v python3 > /dev/null || python_cmd=`python`
 
 BASEDIR=$(dirname $0)
-sudo $python_cmd -u $BASEDIR/nrsrf.py $@
+exec $python_cmd -u $BASEDIR/nrsrf.py $@

hardware/PiSrf/nrsrf.py

@@ -11,8 +11,11 @@ import os, select
 import signal
 
 def signal_handler(sig, frame):
-    sys.exit(0)
+    #sys.exit(0) #Program won't stop with it
+    os._exit(0)
 signal.signal(signal.SIGINT, signal_handler)
+signal.signal(signal.SIGTERM, signal_handler)
+
 
 # Turn off warnings if you run it a second time...
 GPIO.setwarnings(False)
@@ -52,7 +55,7 @@ def Measure():
 # Main program loop
 if len(sys.argv) > 1:
     pins = sys.argv[1].lower().split(',')
-    if len(pins) != 3:
+    if not 3 <= len(pins) <=4 :
         print("Bad parameters supplied")
         print(pins)
         sys.exit(0)
@@ -60,6 +63,7 @@ if len(sys.argv) > 1:
     TRIGGER = int(pins[0])
     ECHO    = int(pins[1])
     SLEEP   = float(pins[2])
+    precision = int(pins[3]) if len(pins) >= 4 else 0
 
     GPIO.setmode(GPIO.BOARD)        # Use GPIO BOARD numbers
     GPIO.setup(TRIGGER, GPIO.OUT)   # Trigger
@@ -74,15 +78,16 @@ if len(sys.argv) > 1:
 
     while True:
         try:
-            distance = int( Measure() + 0.5 )
+            distance = round( Measure(),precision)
+            distance = int(distance) if precision == 0 else distance
             if distance != OLD and distance > 2 and distance < 400:
                 print(distance)
                 OLD = distance
             time.sleep(SLEEP)
-        except:                     # try to clean up on exit
-            print("0.0")
+        except Exception as e:                     # try to clean up on exit
+            print("0.0")            
 
 else:
     print("Bad params")
-    print("    nrsrf.py trigger_pin, echo_pin, rate_in_seconds")
+    print("    nrsrf.py trigger_pin, echo_pin, rate_in_seconds, [precision_digits]")
     sys.exit(0)

hardware/PiSrf/package.json

@@ -1,6 +1,6 @@
 {
     "name"          : "node-red-node-pisrf",
-    "version"       : "0.1.6",
+    "version"       : "0.1.7",
     "description"   : "A Node-RED node for a Raspberry Pi to use a SRF04 or SRF05 range finder",
     "dependencies"  : {
     },
@@ -9,7 +9,7 @@
         "url":"https://github.com/node-red/node-red-nodes/tree/master/hardware/PiSrf"
     },
     "license": "Apache-2.0",
-    "keywords": [ "node-red", "SRF04", "SRF05", "ultrasonic", "range" ],
+    "keywords": [ "node-red", "SRF04", "SRF05", "ultrasonic", "range", "HC-SR04", "SR04" ],
     "node-red"      : {
         "nodes"     : {
             "rpi-srf": "pisrf.js"

hardware/PiSrf/pisrf.html

@@ -7,6 +7,10 @@
     <div class="form-row">
         <label for="node-input-pulse"><i class="fa fa-clock-o"></i> Repeat (S)</label>
         <input type="text" id="node-input-pulse" placeholder="time between readings">
+    </div>
+	<div class="form-row">
+        <label for="node-input-precision"><i class="fa fa-balance-scale"></i>Decimal Places</label>
+        <input type="text" id="node-input-precision" placeholder="decimal places 0 or 1">
     </div>
     <div class="form-row">
         <label for="node-input-topic"><i class="fa fa-bars"></i> Topic</label>
@@ -24,6 +28,7 @@
     <p>Raspberry Pi input from an SRF04 or SRF05 ultrasonic range finder.</p>
     <p>Outputs a <code>msg.payload</code> with a number representing the range in cm.</p>
     <p>Produces one measurement every 0.5s (default) - but only if the distance is different from the previous reading.</p>
+    <p>You can specify resolution up to one decimal place.</p>
     <p><b>Note:</b> we are using the actual physical pin numbers on connector P1 as they are easier to locate.</p>
 </script>
 
@@ -35,7 +40,8 @@
             name: { value:"" },
             topic: { value:"SRF" },
             pulse: {value:"0.5" },
-            pins: { value:"", required:true, validate:RED.validators.regex(/^\d+,\d+$/) }
+            pins: { value:"", required:true, validate:RED.validators.regex(/^\d+,\d+$/) },
+			precision: {value:"0", validate:RED.validators.regex(/^0|1|^$/)}
         },
         inputs:0,
         outputs:1,

hardware/PiSrf/pisrf.js

@@ -33,6 +33,7 @@ module.exports = function(RED) {
         this.topic = n.topic;
         this.pins = n.pins;
         this.pins += ","+(n.pulse || 0.5);
+		this.pins += ","+(n.precision || 0);
         var node = this;
 
         if (allOK === true) {