12.3. Converter Processors¶

Converter processors (PutGeoMesa and ConvertToGeoFile) accept the following configuration parameters for specifying the input source:

Property	Description
`SftName`	Name of the SFT on the classpath to use. This property overrides SftSpec.
`SftSpec`	SFT specification String. Overridden by SftName if both are set.
`FeatureNameOverride`	Override the feature type name on ingest from SftName or SftSpec.
`ConverterName`	Name of converter on the classpath to use. This property overrides ConverterSpec.
`ConverterSpec`	Converter specification string. Overridden by ConverterName if both are set.
`ConverterErrorMode`	Override the converter error mode (`log-errors` or `raise-errors`)
`ConverterMetricReporters`	Override the converter metrics reporters (see below)
`ConvertFlowFileAttributes`	Expose flow file attributes to the converter framework, referenced by name
`ExtraClasspaths`	Additional resources to add to the classpath, e.g. converter and SFT definitions

Additionally, the PutGeoMesa processor accepts additional configuration:

Property	Description
`InitializeSchemas`	Initialize schemas in the underlying data store when the processor is started. Schemas should be defined in standard Java properties format, with the type name as the key, and the feature type specification or lookup as the value

12.3.1. Defining SimpleFeatureTypes and Converters¶

The GeoMesa NiFi processors package a set of predefined SimpleFeatureType schema definitions and GeoMesa converter definitions for popular data sources such as Twitter, GDelt and OpenStreetMaps.

The full list of provided sources can be found in Prepackaged Converter Definitions.

For custom data sources, there are two ways of providing custom SFTs and converters:

12.3.1.1. Providing SimpleFeatureTypes and Converters on the Classpath¶

To bundle configuration in a JAR file simply place your config in a file named reference.conf and place it at the root level of a JAR file:

$ jar cvf data-formats.jar reference.conf

You can verify your JAR was built properly:

$ jar tvf data-formats.jar
Mon Mar 20 18:18:36 EDT 2017 META-INF/
Mon Mar 20 18:18:36 EDT 2017 META-INF/MANIFEST.MF
Mon Mar 20 14:49:54 EDT 2017 reference.conf

Use the ExtraClasspaths property to point your processor to the JAR file. The property takes a list of comma-delimited resources. Once set, the SftName and/or ConverterName properties will update with the name of your converters. You will need to close the configuration panel and re-open it in order for the properties to update.

12.3.1.2. Defining SimpleFeatureTypes and Converters via the UI¶

You may also provide SimpleFeatureTypes and Converters directly in the Processor configuration via the NiFi UI. Simply paste your TypeSafe configuration into the SftSpec and ConverterSpec property fields.

12.3.1.3. Defining SimpleFeatureTypes and Converters via Flow File Attributes¶

You may also override the Processor configuration fields with flow file attributes. The following attributes are available:

geomesa.sft.name corresponds to the Processor configuration FeatureNameOverride
geomesa.sft.spec corresponds to the Processor configuration SftSpec
geomesa.converter corresponds to the Processor configuration ConverterSpec

Warning

Configuration via flow file attributes should be used with care, as any misconfigurations may multiply. For example, setting geomesa.sft.name to a non-recurring value could end up creating a new schema for each flow file, potentially crashing your database by creating too many tables.

12.3.2. Initializing Schemas¶

The InitializeSchemas configuration can be used to create schemas in the underlying data store when the processor is started, instead of having to wait for data to flow through the processor. The schemas are defined as a standard Java properties file, where each line of the configuration should contain the name of a feature type as the key and the definition of the type as the value, corresponding to FeatureNameOverride and SftName / SftSpec (see above). For example:

gdelt=gdelt2
example-csv=example-csv
test=name:String,dtg:Date,*geom:Point:srid=436

12.3.3. Converter Metrics¶

GeoMesa supports publishing metrics on the ingest conversion process. See Metrics and GeoMesa Metrics for details. The GeoMesa NiFi converter processors allow the metrics reporters to be configured directly in NiFi with the ConverterMetricReporters property, instead of in the converter definition. The property expects a TypeSafe Config block defining the reporters or list of reporters, for example:

{
  type     = "slf4j"
  units    = "milliseconds"
  interval = "60 seconds"
  logger   = "org.locationtech.geomesa.metrics"
  level    = "debug"
}