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Wombat

cypher

Introduced in version 4.37.0.

# Common config fields, showing default values
output:
  label: ""
  cypher:
    uri: neo4j://demo.neo4jlabs.com # No default (required)
    cypher: 'MERGE (p:Person {name: $name})' # No default (required)
    database_name: ""
    args_mapping: root.name = this.displayName # No default (optional)
    basic_auth:
      enabled: false
      username: ""
      password: ""
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
    max_in_flight: 64

The cypher output type writes a batch of messages to any graph database that supports the Neo4j or Bolt protocols.

Examples

This is an example of how to write to Neo4j Aura

yaml
output:
  cypher:
    uri: neo4j+s://example.databases.neo4j.io
    cypher: |
      MERGE (product:Product {id: $id})
        ON CREATE SET product.name = $product,
                       product.title = $title,
                       product.description = $description,
    args_mapping: |
      root = {}
      root.id = this.product.id
      root.product = this.product.summary.name
      root.title = this.product.summary.displayName
      root.description = this.product.fullDescription
    basic_auth:
      enabled: true
      username: "${NEO4J_USER}"
      password: "${NEO4J_PASSWORD}"

Fields

uri

The connection URI to connect to. See Neo4j’s documentation for more information.

Type: string

# Examples


uri: neo4j://demo.neo4jlabs.com


uri: neo4j+s://aura.databases.neo4j.io


uri: neo4j+ssc://self-signed.demo.neo4jlabs.com


uri: bolt://127.0.0.1:7687


uri: bolt+s://core.db.server:7687


uri: bolt+ssc://10.0.0.43

cypher

The cypher expression to execute against the graph database.

Type: string

# Examples


cypher: 'MERGE (p:Person {name: $name})'


cypher: |-
  MATCH (o:Organization {id: $orgId})
  MATCH (p:Person {name: $name})
  MERGE (p)-[:WORKS_FOR]->(o)

database_name

Set the target database for which expressions are evaluated against.

Type: string

Default: ""

args_mapping

The mapping from the message to the data that is passed in as parameters to the cypher expression. Must be an object. By default the entire payload is used.

Type: string

# Examples


args_mapping: root.name = this.displayName


args_mapping: 'root = {"orgId": this.org.id, "name": this.user.name}'

basic_auth

Allows you to specify basic authentication.

Type: object

basic_auth.enabled

Whether to use basic authentication in requests.

Type: bool

Default: false

basic_auth.username

A username to authenticate as.

Type: string

Default: ""

basic_auth.password

A password to authenticate with.

Type: string

Default: ""

basic_auth.realm

The realm for authentication challenges.

Type: string

Default: ""

tls

Custom TLS settings can be used to override system defaults.

Type: object

tls.skip_cert_verify

Whether to skip server side certificate verification.

Type: bool

Default: false

tls.enable_renegotiation

Whether to allow the remote server to repeatedly request renegotiation. Enable this option if you’re seeing the error message local error: tls: no renegotiation.

Type: bool

Default: false Requires version 3.45.0 or newer

tls.root_cas

An optional root certificate authority to use. This is a string, representing a certificate chain from the parent trusted root certificate, to possible intermediate signing certificates, to the host certificate.

Type: string

Default: ""

# Examples


root_cas: |-
  -----BEGIN CERTIFICATE-----
  ...
  -----END CERTIFICATE-----

tls.root_cas_file

An optional path of a root certificate authority file to use. This is a file, often with a .pem extension, containing a certificate chain from the parent trusted root certificate, to possible intermediate signing certificates, to the host certificate.

Type: string

Default: ""

# Examples


root_cas_file: ./root_cas.pem

tls.client_certs

A list of client certificates to use. For each certificate either the fields cert and key, or cert_file and key_file should be specified, but not both.

Type: array

Default: []

# Examples


client_certs:
  - cert: foo
    key: bar


client_certs:
  - cert_file: ./example.pem
    key_file: ./example.key

tls.client_certs[].cert

A plain text certificate to use.

Type: string

Default: ""

tls.client_certs[].key

A plain text certificate key to use.

Type: string

Default: ""

tls.client_certs[].cert_file

The path of a certificate to use.

Type: string

Default: ""

tls.client_certs[].key_file

The path of a certificate key to use.

Type: string

Default: ""

tls.client_certs[].password

A plain text password for when the private key is password encrypted in PKCS#1 or PKCS#8 format. The obsolete pbeWithMD5AndDES-CBC algorithm is not supported for the PKCS#8 format.

Because the obsolete pbeWithMD5AndDES-CBC algorithm does not authenticate the ciphertext, it is vulnerable to padding oracle attacks that can let an attacker recover the plaintext.

Type: string

Default: ""

# Examples


password: foo


password: ${KEY_PASSWORD}

batching

Allows you to configure a batching policy.

Type: object

# Examples


batching:
  byte_size: 5000
  count: 0
  period: 1s


batching:
  count: 10
  period: 1s


batching:
  check: this.contains("END BATCH")
  count: 0
  period: 1m

batching.count

A number of messages at which the batch should be flushed. If 0 disables count based batching.

Type: int

Default: 0

batching.byte_size

An amount of bytes at which the batch should be flushed. If 0 disables size based batching.

Type: int

Default: 0

batching.period

A period in which an incomplete batch should be flushed regardless of its size.

Type: string

Default: ""

# Examples


period: 1s


period: 1m


period: 500ms

batching.check

A Bloblang query that should return a boolean value indicating whether a message should end a batch.

Type: string

Default: ""

# Examples


check: this.type == "end_of_transaction"

batching.processors

A list of processors to apply to a batch as it is flushed. This allows you to aggregate and archive the batch however you see fit. Please note that all resulting messages are flushed as a single batch, therefore splitting the batch into smaller batches using these processors is a no-op.

Type: array

# Examples


processors:
  - archive:
      format: concatenate


processors:
  - archive:
      format: lines


processors:
  - archive:
      format: json_array

max_in_flight

The maximum number of messages to have in flight at a given time. Increase this to improve throughput.

Type: int

Default: 64