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Table Of Contents

FortheuserdocumentationofNode-RED,pleaserefertoNode-RED'swebsite:nodered.org.

Seealso:"OLConnectStartupflow"onpage189

Tip: Addadebugnodeafteranodetoverifythatthecontentsofapropertyofthemsgobjectare

changedasexpected.

Nodes used in OL Connect flows

Inadditiontothe"OLConnectnodes"onpage182,thesestandardnodeswilloftenbeusedinOLCon-

nectapplications:

l

Theinjectnodetriggerstheflow.Itcanbesetupinawaythatittriggerstheflowwheneveritis

deployedorwhenNode-REDisstarted(see"OLConnectStartupflow"onpage189).Itcanalso

beusedtoinjectthefullpathtoa(sample)datafileintoaflow.

l

TheHTTP innodecreatesanHTTPend-pointforcreatingwebservices.

l

AnyflowthatstartswithanHTTPinnodemusthaveapathtoanHTTP responsenodeoth-

erwiserequestswilleventuallytimeout.

l

Theread filenodeloadsafile.IfthefileisaJSONfile,theresultisaJSONstring.

l

Thewrite filewritesthecontentofmsg.payloadtoafile.

l

TheJSONnodeparsesaJSONstringandaddsthekeyswiththeirvaluesaspropertiesto

msg.payload.

l

Thechangenodecaninitializevariablesandchangetheirvalue.

l

ThefunctionnodeexecutesJavaScriptcode.Seehttps://nodered.org/docs/user-guide/writing-

functions.

l

Thedebugnodedisplaysthecontentofthemsgobject,whichispassedbetweennodesina

flow,inthedebugmessageconsole.Addadebugnode-oneforeachpropertyofthemsgobject

-afteranothernodetoverifythatthepropertiesarechangedasexpected.

l

Thesplitnodeturnsasinglemsg.payloadconsistingofanarrayintoaseriesofmessages,

eachofwhichhasapayloadcontainingoneofthearray'selements.NotethattheSplitnodeonly

worksonmsg.payloadandnotonitschildobjects.

l

theabilitytohavemultipleoutputchannelsinaSwitchnodeandthefactthatthesechannelscan

belinkedbacktoanodeontheprimary/mainbranchdownstream.

Thesearesomeusefulnodescreatedbythirdparties:

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