Node RED
Balthasar Hofer
Vorweg: Account auf https://render.com erstellen
Anwendungsbereiche
API Abfragen
- Erstellen Sie einen neuen Flow
- Fügen Sie 3 Knoten hinzu:
- Doppelklicken des HTTP Requests
- als URL die ChuckNorris API eintragen
- Deploy...
API Abfragen
Im Debug-Fenster sehen Sie roten Text angezeigt
👉 Antwort ist im Format JSON (JavaScriptObjectNotation)
👉 Wir können die Antwort als JSON einlesen, dann können wir die einzelnen Felder abgreifen
API Abfragen
Basics
Ein Flow mit mehreren Nodes
{
/* Zwischen Nodes werden Nachrichten
* weitergegeben. */
payload: 'Hallo Welt'
}
Eigenschaften Bearbeiten
Ausgabe: Debug Node
Nachrichten Bearbeiten
Funktion > Change
Nachrichten Bearbeiten
Funktion > function
Plain Javascript Function
// "msg" ist in jedem JS-Node vorhanden
const data = {
time: Date.now(),
fluss: msg.payload.fluss.toUpperCase(),
temperatur: Number.parseFloat(msg.payload.data[2])
}
msg.payload = data;
return msg;Dokumente im Internet: HTML
https://www.hydrodaten.admin.ch/de/2135.html
F12
oder
Einstellungen > Weitere Tools > Entwicklungstools
<table class="table">
<tbody>
<tr>
<th scope="row">Letzter Messwert</th>
<td class="text-center">52</td>
<td class="text-center">501.53</td>
<td class="text-center">8.7</td>
</tr>
</tbody>
</table>Dokumente im Internet: HTML
document.querySelector('table td'){
"fluss": "h1 strong",
"wasser": {
"listItem": "#content table td"
}
}Dokumente im Internet: HTML
document.querySelector('table td')
Dashboard
msg.topic = 'Temperatur'
msg.payload = 8.2
return msg;https://node-red.onrender.com/ui
/help
/newbot
Telegram
Aktuell die simpelste Konfiguration...
→ neuer Chatbot erstellen
Name muss mit "bot" enden
→ eigene Chat-ID abfragen
Name muss mit "bot" enden
/start
Telegram Command
const temperatur = msg.payload.scrapped.wasser[2];
const wasserstand = msg.payload.scrapped.wasser[1];
const abfluss = msg.payload.scrapped.wasser[0]
msg.payload = {
fluss: msg.payload.scrapped.fluss,
temperatur: temperatur,
wasserstand: wasserstand,
abfluss: abfluss
}
/* im flow als state speichern */
flow.set('Aare', msg.payload);
return msg;Die zuletzt abgefragte Temperatur abfragen
msg.payload.type = 'message';
/* den letzten State wieder holen */
const aare = flow.get('Aare');
msg.payload.content = JSON.stringify(aare);
msg.payload.chatId = 9999999999;
return msg;Die zuletzt abgefragte Temperatur abfragen
[
{
"id": "3fc70412f62a6de8",
"type": "tab",
"label": "Wasserbot",
"disabled": false,
"info": "",
"env": []
},
{
"id": "fb9b0c1b17366974",
"type": "inject",
"z": "3fc70412f62a6de8",
"name": "",
"props": [
{
"p": "payload"
},
{
"p": "topic",
"vt": "str"
}
],
"repeat": "15",
"crontab": "",
"once": false,
"onceDelay": 0.1,
"topic": "",
"payload": "",
"payloadType": "date",
"x": 250,
"y": 140,
"wires": [
[
"815fae1221aa1f33"
]
]
},
{
"id": "815fae1221aa1f33",
"type": "http request",
"z": "3fc70412f62a6de8",
"name": "",
"method": "GET",
"ret": "txt",
"paytoqs": "ignore",
"url": "https://www.hydrodaten.admin.ch/de/2135.html",
"tls": "",
"persist": false,
"proxy": "",
"insecureHTTPParser": false,
"authType": "",
"senderr": false,
"headers": [],
"x": 410,
"y": 140,
"wires": [
[
"812c2ba83a0cd65c"
]
]
},
{
"id": "8845852f45cd0606",
"type": "debug",
"z": "3fc70412f62a6de8",
"name": "Debug Scrape",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "payload",
"targetType": "msg",
"statusVal": "",
"statusType": "auto",
"x": 440,
"y": 260,
"wires": []
},
{
"id": "812c2ba83a0cd65c",
"type": "scrape",
"z": "3fc70412f62a6de8",
"name": "",
"mapping": "{\"fluss\":\"h1 strong\",\"wasser\":{\"listItem\":\"#content table td\"}}",
"x": 570,
"y": 140,
"wires": [
[
"f530a7d8dc64d60b"
]
]
},
{
"id": "f530a7d8dc64d60b",
"type": "function",
"z": "3fc70412f62a6de8",
"name": "extract",
"func": "const temperatur = msg.payload.scrapped.wasser[2];\nconst wasserstand = msg.payload.scrapped.wasser[1];\nconst abfluss = msg.payload.scrapped.wasser[0]\n\nmsg.payload = {\n fluss: msg.payload.scrapped.fluss,\n temperatur: temperatur,\n wasserstand: wasserstand,\n abfluss: abfluss\n}\n/* im flow als state speichern */\nflow.set('Aare', msg.payload);\n\nreturn msg;",
"outputs": 1,
"noerr": 0,
"initialize": "// Der Code hier wird ausgeführt,\n// wenn der Node gestartet wird\nflow.set('Aare', {})",
"finalize": "",
"libs": [],
"x": 250,
"y": 260,
"wires": [
[
"cfbda2c70bc4f2d4",
"8845852f45cd0606",
"723e45e9a3503dbb",
"0f57828dc752b02e"
]
]
},
{
"id": "6d2122136319e6a3",
"type": "ui_chart",
"z": "3fc70412f62a6de8",
"name": "",
"group": "8b26fab51daa72db",
"order": 0,
"width": 0,
"height": 0,
"label": "Temperatur",
"chartType": "line",
"legend": "false",
"xformat": "HH:mm:ss",
"interpolate": "linear",
"nodata": "",
"dot": false,
"ymin": "",
"ymax": "",
"removeOlder": 1,
"removeOlderPoints": "",
"removeOlderUnit": "86400",
"cutout": 0,
"useOneColor": false,
"useUTC": false,
"colors": [
"#1f77b4",
"#aec7e8",
"#ff7f0e",
"#2ca02c",
"#98df8a",
"#d62728",
"#ff9896",
"#9467bd",
"#c5b0d5"
],
"outputs": 1,
"useDifferentColor": false,
"className": "",
"x": 610,
"y": 320,
"wires": [
[]
]
},
{
"id": "cfbda2c70bc4f2d4",
"type": "change",
"z": "3fc70412f62a6de8",
"name": "Temperatur",
"rules": [
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "msg.payload.temperatur",
"tot": "jsonata"
},
{
"t": "set",
"p": "topic",
"pt": "msg",
"to": "Temperatur",
"tot": "str"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 430,
"y": 320,
"wires": [
[
"6d2122136319e6a3"
]
]
},
{
"id": "fc215cddfa992356",
"type": "ui_chart",
"z": "3fc70412f62a6de8",
"name": "",
"group": "8b26fab51daa72db",
"order": 0,
"width": 0,
"height": 0,
"label": "Wasserstand",
"chartType": "line",
"legend": "false",
"xformat": "HH:mm:ss",
"interpolate": "linear",
"nodata": "",
"dot": false,
"ymin": "",
"ymax": "",
"removeOlder": 1,
"removeOlderPoints": "",
"removeOlderUnit": "86400",
"cutout": 0,
"useOneColor": false,
"useUTC": false,
"colors": [
"#1f77b4",
"#aec7e8",
"#ff7f0e",
"#2ca02c",
"#98df8a",
"#d62728",
"#ff9896",
"#9467bd",
"#c5b0d5"
],
"outputs": 1,
"useDifferentColor": false,
"className": "",
"x": 610,
"y": 360,
"wires": [
[]
]
},
{
"id": "723e45e9a3503dbb",
"type": "change",
"z": "3fc70412f62a6de8",
"name": "Wasserstand",
"rules": [
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "msg.payload.wasserstand",
"tot": "jsonata"
},
{
"t": "set",
"p": "topic",
"pt": "msg",
"to": "Wasserstand",
"tot": "str"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 430,
"y": 360,
"wires": [
[
"fc215cddfa992356"
]
]
},
{
"id": "225a76a607dd1f51",
"type": "ui_chart",
"z": "3fc70412f62a6de8",
"name": "",
"group": "8b26fab51daa72db",
"order": 0,
"width": 0,
"height": 0,
"label": "Abfluss",
"chartType": "line",
"legend": "false",
"xformat": "HH:mm:ss",
"interpolate": "linear",
"nodata": "",
"dot": false,
"ymin": "",
"ymax": "",
"removeOlder": 1,
"removeOlderPoints": "",
"removeOlderUnit": "86400",
"cutout": 0,
"useOneColor": false,
"useUTC": false,
"colors": [
"#1f77b4",
"#aec7e8",
"#ff7f0e",
"#2ca02c",
"#98df8a",
"#d62728",
"#ff9896",
"#9467bd",
"#c5b0d5"
],
"outputs": 1,
"useDifferentColor": false,
"className": "",
"x": 600,
"y": 400,
"wires": [
[]
]
},
{
"id": "0f57828dc752b02e",
"type": "change",
"z": "3fc70412f62a6de8",
"name": "Abfluss",
"rules": [
{
"t": "set",
"p": "payload",
"pt": "msg",
"to": "msg.payload.abfluss",
"tot": "jsonata"
},
{
"t": "set",
"p": "topic",
"pt": "msg",
"to": "Abfluss",
"tot": "str"
}
],
"action": "",
"property": "",
"from": "",
"to": "",
"reg": false,
"x": 420,
"y": 400,
"wires": [
[
"225a76a607dd1f51"
]
]
},
{
"id": "78a2bde059edc5be",
"type": "telegram command",
"z": "3fc70412f62a6de8",
"name": "Aare",
"command": "/aare",
"description": "Aare",
"registercommand": true,
"language": "",
"scope": "default",
"bot": "d7e389ca7c8d82d4",
"strict": false,
"hasresponse": true,
"useregex": false,
"removeregexcommand": false,
"outputs": 2,
"x": 210,
"y": 520,
"wires": [
[
"af3d801ae7c0e34e",
"08717ffbaf57bed3"
],
[]
]
},
{
"id": "af3d801ae7c0e34e",
"type": "function",
"z": "3fc70412f62a6de8",
"name": "Aare",
"func": "msg.payload.type = 'message';\nconst aare = flow.get('Aare');\nmsg.payload.content = JSON.stringify(aare);\nmsg.payload.chatId = 99999999;\nreturn msg;",
"outputs": 1,
"noerr": 0,
"initialize": "",
"finalize": "",
"libs": [],
"x": 390,
"y": 520,
"wires": [
[
"a1be1d73aeaf6b6a"
]
]
},
{
"id": "a1be1d73aeaf6b6a",
"type": "telegram sender",
"z": "3fc70412f62a6de8",
"name": "",
"bot": "d7e389ca7c8d82d4",
"haserroroutput": false,
"outputs": 1,
"x": 590,
"y": 520,
"wires": [
[]
]
},
{
"id": "08717ffbaf57bed3",
"type": "debug",
"z": "3fc70412f62a6de8",
"name": "Debug Telegram",
"active": true,
"tosidebar": true,
"console": false,
"tostatus": false,
"complete": "payload",
"targetType": "msg",
"statusVal": "",
"statusType": "auto",
"x": 420,
"y": 480,
"wires": []
},
{
"id": "8b26fab51daa72db",
"type": "ui_group",
"name": "Standard",
"tab": "152f68bd903e15a5",
"order": 1,
"disp": true,
"width": "6",
"collapse": false,
"className": ""
},
{
"id": "d7e389ca7c8d82d4",
"type": "telegram bot",
"botname": "fata",
"usernames": "",
"chatids": "",
"baseapiurl": "",
"updatemode": "polling",
"pollinterval": "1000",
"usesocks": false,
"sockshost": "",
"socksprotocol": "socks5",
"socksport": "6667",
"socksusername": "anonymous",
"sockspassword": "",
"bothost": "",
"botpath": "",
"localbotport": "8443",
"publicbotport": "8443",
"privatekey": "",
"certificate": "",
"useselfsignedcertificate": false,
"sslterminated": false,
"verboselogging": false
},
{
"id": "152f68bd903e15a5",
"type": "ui_tab",
"name": "Home",
"icon": "dashboard",
"disabled": false,
"hidden": false
}
]Code: Kann über Menü > Import eingefügt werden
Troubleshooting:
Render.com...
(1) Render ist kostenlos... weil es sich nach 15 Minuten ohne Request in einen Schlafmodus versetzt...
Lösung: Ein Flow, der alle 5 Minuten einen Request auf die eigene Domain macht
(2) Render bietet für 3 Monate eine kostenlose PG-Datenbank (danach wird sie gelöscht). Wer eine kostenlose Variante möchte: https://github.com/lebalz/node-red-render-no-db --> DB Connection String auf http://elephantsql.com konfigurieren
(3) Node-Red ist nicht mehr erreichbar: über render.com den letzten commit neu deployen