Below is a table containing all of the configurable options within the Lens Writer. To see how to set config variables, see the Quick Start Guide or the full User Guide. Mandatory variables are highlighted in red.

Lens Writer Configuration

Environment Variable	Default Value	Description	Version

Environment Variable	Default Value	Description	Version
FRIENDLY_NAME	Lens-Writer	The name you wish to set your Writer up with.	v1.3+
LICENSE		The License key provided required for running the Writer.	v1.3+
TRIPLESTORE_ENDPOINT		The endpoint for your Triple Store you wish to upload your RDF to.	v1.3+
TRIPLESTORE_TYPE	sparql	The Triple Store type, some graphs will support the default `sparql` type (e.g. AllegroGraph), however certain graphs require specific type declaration, these include `graphdb`, `stardog`, `blazegraph`, `neptune`, and `neo4j`.	v1.3+
TRIPLESTORE_REASONING	false	Whether you want reasoning enabled or disabled.	v1.3+
TRIPLESTORE_USERNAME		The username of your Triple Store. Leave blank if your Triple Store does not require any authentication.	v1.3+
TRIPLESTORE_PASSWORD		The password of your Triple Store. Leave blank if your Triple Store does not require any authentication.	v1.3+
S3_REGION	us-east-1	The region in AWS where your files and services reside. Note: all services must be in the same region.	v1.3+
AWS_ACCESS_KEY		Your access key for AWS.	v1.3+
AWS_SECRET_KEY		Your secret key for AWS.	v1.3+
DELETE_SOURCE	false	Whether you wish to delete the source NQuads file after it has been written to the Triple Store	v1.3+
LENS_RUN_STANDALONE	false	The Lens Writer is designed to run as part of a larger end to end system with the Lens providing the Writer with RDF files to write to a Triple Store. As part of this process, Kafka is used to communicate between services. This is enabled by default, however if you want to run the Lens Writer as standalone without communicating to other services, set this property to true.	v1.3+
INGESTION_MODE	insert	How to process the ingested data. `'insert'`: the new data are ingested in full and are no linked with already existing data. The new dataset adds new value to already existing subject-predicate. `'update'`: the new data are used for updating the existing data. The new dataset replaces value in existing subject-predicate.	v1.4+

Kafka Configuration

Environment Variable	Default Value	Description	Version

Environment Variable	Default Value	Description	Version
KAFKA_BROKERS	localhost:9092	The Kafka Broker is what tells the Writer where to look for your Kafka Cluster. Set with the following structure `<kafka-ip>:<kafka-port>`. The recommended port is `9092`.	v1.3+
KAFKA_TOPIC_NAME_SOURCE	source_urls	The topic used for the Consumer to read messages from containing input file URLs in order to ingest data.	v1.3+
KAFKA_TOPIC_NAME_DLQ	dead_letter_queue	The topic used to push messages containing reasons for failure within the Writer. These messages are represented as a JSON.	v1.3+
KAFKA_TOPIC_NAME_SUCCESS	success_queue	The topic used for the messages sent containing the file URLs of the successfully transformed RDF data files.	v1.3+
KAFKA_GROUP_ID_CONFIG	consumerGroup1	The identifier of the group this consumer belongs to.	v1.3+
KAFKA_AUTO_OFFSET_RESET_CONFIG	earliest	What to do when there is no initial offset in Kafka or if an offset is out of range. `earliest`: automatically reset the offset to the earliest offset `latest`: automatically reset the offset to the latest offset	v1.3+
KAFKA_MAX_POLL_RECORDS	100	The maximum number of records returned in a single call to poll.	v1.3+
KAFKA_TIMEOUT	1000000	Kafka consumer polling time out.	v1.3+

Neo4j Configuration

Environment Variable	Default Value	Description	Version

Environment Variable	Default Value	Description	Version
NEO4J_HANDLE_VOCAB_URIS	KEEP	`'SHORTEN'`: Full URIs are shortened using prefixes for property names, relationship names and labels `'IGNORE'`: URIs are ignored and only local names are kept `'MAP'`: Vocabulary element mappings are applied on import `'KEEP'`: URIs are kept unchanged	v1.3+
NEO4J_APPLY_NEO4J_NAMING	false	When set to true and in combination with `handleVocabUris: 'IGNORE'`, Neo4j capitalisation is applied to vocabulary elements (all caps for relationship types, capital first for labels, etc.)	v1.3+
NEO4J_HANDLE_MULTIVAL	ARRAY	`'OVERWRITE'`: Property values are kept single-valued. Multiple values in the imported RDF are overwritten (only the last one is kept). `'ARRAY'`: Properties are stored in an array enabling storage of multiple values.	v1.3+
NEO4J_KEEP_LANG_TAG	true	When set to true, the language tag is kept along with the property value. Useful for multilingual datasets.	v1.3+
NEO4J_TYPES_TO_LABEL	false	When set to true, `rdf:type` statements are imported as node labels in Neo4j.	v1.3+
NEO4J_VERIFY_URI_SYNTAX	true	By default, URI syntax is checked. This can be disabled by setting this parameter to `false`.	v1.3+
NEO4J_KEEP_CUSTOM_DATA_TYPES	true	When set to true, all properties containing a custom data type will be saved as a string followed by their custom data type IRIs.	v1.3+

Provenance Configuration

Environment Variable	Default Value	Description	Version

Environment Variable	Default Value	Description	Version
RECORD_PROVO	false	Currently, the Lens Writer does not generate its own provenance meta-data and so this option is set to false	v1.3+

Logging Configuration

Environment Variable	Default Value	Description	Version

Environment Variable	Default Value	Description	Version
LOGGING_LEVEL	WARN	Global log level	v1.3+
LOGGING_LOGGERS_DATALENS	DEBUG	Log level for Data Lens loggers	v1.3+
LOGGING_LOGGERS_DROPWIZARD	INFO	Log level for Dropwizard loggers	v1.3+
LOGGING_APPENDERS_CONSOLE_TIMEZONE	UTC	Timezone for console logging	v1.3+
LOGGING_APPENDERS_TXT_FILE_THRESHOLD	ALL	Threashold for text logging	v1.3+
Log Format (not overridable)	%-6level [%d{HH:mm:ss.SSS}] [%t] %logger{5} - %X{code} %msg %n	Pattern for logging messages	v1.3+
Current Log Filename (not overridable)	/var/log/datalens/text/current/application_${applicationName}_${timeStamp}.txt.log	Pattern for log file name	v1.3+
LOGGING_APPENDERS_TXT_FILE_ARCHIVE	true	Archive log text files	v1.3+
Archived Log Filename Pattern (not overridable)	/var/log/datalens/text/archive/application_${applicationName}_${timeStamp}_to_%d{yyyy-MM-dd}.txt.log	Log file rollover frequency depends on pattern in following property. For example %d{yyyy-MM-ww} declares rollover weekly	v1.3+
LOGGING_APPENDERS_TXT_FILE_ARCHIVED_TXT_FILE_COUNT	7	Max number of archived text files	v1.3+
LOGGING_APPENDERS_TXT_FILE_TIMEZONE	UTC	Timezone for text file logging	v1.3+
LOGGING_APPENDERS_JSON_FILE_THRESHOLD	ALL	Threashold for text logging	v1.3+
Log Format (not overridable)	%-6level [%d{HH:mm:ss.SSS}] [%t] %logger{5} - %X{code} %msg %n	Pattern for logging messages	v1.3+
Current Log Filename (not overridable)	/var/log/datalens/json/current/application_${applicationName}_${timeStamp}.json.log	Pattern for log file name	v1.3+
LOGGING_APPENDERS_JSON_FILE_ARCHIVE	true	Archive log text files	v1.3+
Archived Log Filename Pattern (not overridable)	/var/log/datalens/json/archive/application_${applicationName}_${timeStamp}_to_%d{yyyy-MM-dd}.json.log	Log file rollover frequency depends on pattern in following property. For example %d{yyyy-MM-ww} declares rollover weekly	v1.3+
LOGGING_APPENDERS_JSON_FILE_ARCHIVED_FILE_COUNT	7	Max number of archived text files	v1.3+
LOGGING_APPENDERS_JSON_FILE_TIMEZONE	UTC	Timezone for text file logging	v1.3+
LOGGING_APPENDERS_JSON_FILE_LAYOUT_TYPE	json	The layout type for the json logger	v1.3+

Data Lens: Documentation

Configurable Options - Lens Writer v1.4

Lens Writer Configuration

Kafka Configuration

Neo4j Configuration

Provenance Configuration

Logging Configuration