Using the NiFi API

Russell Bateman
10 April 2023
last update:

NiFi API services layout (entry point URIs)

API Module	URI path	Description
Access	/access	authenticate user and get access token from NiFi
Controller	/controller	manage the cluster and create reporting task
Controller Services	/controller-services	manage controller services and update controller service references
Reporting Tasks	/reporting-tasks	manage reporting tasks
Flow	/flow	get the data flow metadata and component status and query history
Process Groups	/process-groups	upload and instantiate a template and create components
Processors	/processors	create and schedule a processor and set its properties
Connections	/connections	create a connection, set queue priority and update connection destination
FlowFile Queues	/flowfile-queues	view queue contents, download flowfile content, and empty queue
Remote Process Groups	/remote-process-groups	create a remote group and enable transmission
Provenance	/provenance	query provenance, and search event lineage

For example, getting information about the flow...

(The return is wrapped for readability.)

$ GET http://localhost:9113/nifi-api/flow/about

{"about":{"title":"NiFi","version":"1.13.2","uri":"http://localhost:9113/nifi-api/","contentViewerUrl":"../nifi-content-viewer/","timezone":"MDT","buildTag":"nifi-1.13.2-RC1","buildRevision":"174938e","buildBranch":"UNKNOWN","buildTimestamp":"03/17/2021 20:45:53 MDT"}}

...or:

{
  "about":
  {
    "title":            "NiFi",
    "version":          "1.13.2",
    "uri":              "http://localhost:9113/nifi-api/",
    "contentViewerUrl": "../nifi-content-viewer/",
    "timezone":         "MDT",
    "buildTag":         "nifi-1.13.2-RC1",
    "buildRevision":    "174938e",
    "buildBranch":      "UNKNOWN",
    "buildTimestamp":   "03/17/2021 20:45:53 MDT"
  }
}

Steps to using the NiFi API to interact with templates...

Creating NiFi Template via Rest API.

1. Fetch access token...

   $ curl --request POST \
          --header "Accept: */*" \
          --header "Accept-Encoding: gzip" \
          --header "Accept-Language: en-US,en;q=0.5" \
          --header "Connection: keep-alive" \
          --header "Content-Length: 38" \
          --header "Content-Type: application/x-www-form-urlencoded; charset=UTF-8" \
          --header "Host: http://localhost:9113" \
          --header "Referer: http://localhost:9113/nifi/login" \
          --header "X-Requested-With: XMLHttpRequest" \
          --data   'username=myUserName&password=YourPasswordHere' \
          http://localhost:9113/nifi-api/access/token \
     | gunzip
   
   
   
   curl --request POST --header "Accept: */*" --header "Accept-Encoding: gzip" --header "Accept-Language: en-US,en;q=0.5" --header "Connection: keep-alive" --header "Content-Length: 38" --header "Content-Type: application/x-www-form-urlencoded; charset=UTF-8" --header "Host: http://localhost:9113" --header "Referer: http://localhost:9113/nifi/login" --header "X-Requested-With: XMLHttpRequest" http://localhost:9113/nifi-api/access/token
   
   

2. Fetch the UUID of the process group that interests you.