Migrating templates using a directory with template.xml files as input

bin/migration.sh nifi migrate-templates \
-i /etc/migration-tool-input \
-od /etc/migration-tool-output/templates \
-sco

This generates a sourceVersion folder that contains the output files of the migration.

templates
└── sourceVersion
    ├── Elastic_template_b4175f57-0194-1000-8470-9251a24519b4
    │   └── Elastic_template.json
    ├── TCP_Listener_template_b41940d7-0194-1000-42fc-458834630567
    │   └── TCP_Listener_template.json
    └── activity_log.json

The folder name Elastic_template_b4175f57-0194-1000-8470-9251a24519b4 and TCP_Listener_template_b41940d7-0194-1000-42fc-45883463056 are temporary process groups which were created during the migration process and used to separate the components in the template from other components that may be present during the migration.

Elastic_template.json

• Flow definition containing the contents of the original template

• Equivalent to manually converting a template to a flow definition in NiFi 1 by:

  1. Instantiating the template on the canvas.
  2. Right-clicking the process group.
  3. Selecting Download flow definition without external services.

• Modified by the Migration Tool to ensure compatibility:

  • Variables (not supported in NiFi 2) converted into parameters
  • Parameter context created to hold the new parameters
  • Processors updated to reference parameters instead of variables

• This is still a NiFi 1 flow definition, so do not load this file directly into NiFi 2. Use an empty NiFi 1 instance to review the modification made by the tool. The flow will appear unchanged, but variables will be replaced with parameters of the same name, which are now referenced by the processor instead.

• Changes in the syntax: Variables were previously referenced using ${}, whereas parameters are now referenced using #{}.

  • NiFi 1 variables: ${variable_name}
  • NiFi 2 parameters: #{parameter_name}

TCP_Listener_template.json

• A modified flow definition, which is not compatible with NiFi 2 yet.

• It contains everything the original flow definition did, except the TCP Listener process group now references a parameter instead of the removed variable.

• This is still a NiFi 1 flow definition, so do not load this file directly into NiFi 2. Use an empty NiFi 1 instance to review the modification made by the tool. The flow definition will appear unchanged, but variables will be replaced with parameters of the same name, which are now referenced by the processor instead.

• Changes in syntax: Variables were previously referenced using ${}, whereas parameters are now referenced using #{}.

  • NiFi 1 variables: ${variable_name}
  • NiFi 2 parameters: #{parameter_name}

activity_log.json

• Log of all actions performed during this stage of the migration.

• The following were changes made during the template migration:

  • A new parameter context was created with a new parameter called TCP Listener Port, which replaces the corresponding variable.
  • The TCP Listener Port variable was removed.
  • A new parameter context was created with a new parameter called Elasticsearch Index, which replaces the corresponding variable of the same name.
  • The new parameter is referenced from the PutElasticsearchJson processor.
  • The Elasticsearch Index variable was removed.

bin/migration.sh nifi migrate-templates \
-i /etc/migration-tool-input \
-od /etc/migration-tool-output/templates

The contents of the previously generated sourceVersion folder will be overwritten, but this is not a concern as the tool generates the same sourceVersion output as before. Additionally, a targetVersion directory is created, containing the output files of the Stage 2 part of the migration.

targetVersion
├── Elastic_template_b4175f57-0194-1000-8470-9251a24519b4
│   └── Elastic_template.json
├── TCP_Listener_template_b41940d7-0194-1000-42fc-458834630567
│   └── TCP_Listener_template.json
└── activity_log.json

Elastic_template.json

• NiFi 2-compatible flow definition

• Contains the contents of the original template converted into an exported process group.

• This version is compatible with NiFi 2, but no longer supports NiFi 1.

activity_log.json

• List of all actions performed during this stage of the migration.