Answers to questions:
Templates are stored on the NiFi cluster where they are saved or uploaded. See article visuals on how to access them. Correct ... down/uploaded via UI or API. (I believe the community is working on a central repository for templates, accessible by all UI instances ... in the works however) It is similar to code. Keep in mind when discussing templates you should think of them as either reusable assets (checked out to be used across the team or enterprise for reuse) and full flows (checked out after passing testing, to be promoted to new envt, e.g QA to UAT or Prod). See diagram in SDLC section of article. From reading NiFi literature, I think system and OS properties are splitting hairs around properties we can retrieve directly from the OS (system property like line separator in java, OS property like what you set with export) Good question ... will test and update this answer. No, but you could handle this by giving your property names namespaces for a process group, etc. E.g. you could prepend the process group name or last 10 digits of uid in front of property name. E.g 034g345d2.filepath, 034g345d2.threshold and 034f423ee1.filepath, 034f423ee1.threshold to specify the same properties per process group. No, that is the really powerful part about this ... as the article states, each processor, process group or connection has a UUID with the first part a global id and the second part an instance id. When you download the template, the instance id is replaced by all 0s. When you upload to the canvas, the instance id is given a unique sequence. In that way you can reuse these templates as many times and at as many hierarchy levels as you want. (Works the same way with copy-paste ... you can copy any processor, or connections of processors (subflow), or process group and paste into flows as many times as you wish. Works because each paste creates a new instance id for each component).
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