Connect

cypher

Writes a batch of messages to any graph database that supports the Neo4j and Bolt URI schemes. For each incoming message, the connector can perform operations to store or delete data within the database using the Cypher query language.

Introduced in version 4.37.0.

  • Common

  • Advanced

output:
  label: ""
  cypher:
    uri: "" # No default (required)
    cypher: "" # No default (required)
    database_name: ""
    args_mapping: "" # No default (optional)
    basic_auth:
      enabled: false
      username: ""
      password: ""
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
    max_in_flight: 64
output:
  label: ""
  cypher:
    uri: "" # No default (required)
    cypher: "" # No default (required)
    database_name: ""
    args_mapping: "" # No default (optional)
    basic_auth:
      enabled: false
      username: ""
      password: ""
      realm: ""
    tls:
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
      processors: [] # No default (optional)
    max_in_flight: 64

Examples

Write to Neo4j Aura

This is an example of how to write to Neo4j Aura

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

args_mapping

The mapping from the message to the data that is passed in as parameters to the cypher expression. The mapping must return 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

Configure basic authentication for requests to your graph database.

Type: object

basic_auth.enabled

Whether to authenticate with the graph database using username, password, and realm. When false, the connection is made without authentication.

Type: bool

Default: false

basic_auth.password

The password to use for authentication. Used together with username for basic authentication.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

basic_auth.realm

The realm or process for authentication challenges.

Type: string

Default: ""

basic_auth.username

The username of the account credentials to authenticate as. Used together with password for basic authentication.

Type: string

Default: ""

batching

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.byte_size

The maximum total size (in bytes) that a batch can reach before it is flushed. When the combined size of all messages in the batch reaches or exceeds this limit, the batch is immediately sent to the next stage (such as a processor or output).

Set to 0 to disable size-based batching. When disabled, messages are flushed based on other conditions (such as count or period).

Type: int

Default: 0

batching.check

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

Type: string

Default: ""

# Examples:
check: this.type == "end_of_transaction"

batching.count

The number of messages at which the batch is flushed. Set to 0 to disable count-based batching.

Type: int

Default: 0

batching.period

The length of time after which an incomplete batch is flushed regardless of its size. This field accepts Go duration format strings such as 100ms, 1s, or 5s. Supported time units are ns, us, ms, s, m, and h.

Type: string

Default: ""

# Examples:
period: 1s

# ---

period: 1m

# ---

period: 500ms

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. All resulting messages are flushed as a single batch, so splitting the batch into smaller batches with these processors has no effect.

Type: array<processor>

# Examples:
processors:
  - archive:
      format: concatenate


# ---

processors:
  - archive:
      format: lines


# ---

processors:
  - archive:
      format: json_array

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 against which expressions are evaluated.

Type: string

Default: ""

max_in_flight

The maximum number of messages to have in flight at a given time. For outputs that send messages in batches, this limit applies to message batches. Increase this value to improve throughput.

Type: int

Default: 64

tls

Configure Transport Layer Security (TLS) settings to secure network connections. This includes options for standard TLS as well as mutual TLS (mTLS) authentication where both client and server authenticate each other using certificates. Key configuration options include client_certs for mTLS authentication, root_cas/root_cas_file for custom certificate authorities, and skip_cert_verify for development environments.

Type: object

tls.client_certs[]

A list of client certificates for mutual TLS (mTLS) authentication. Configure this field to enable mTLS, authenticating the client to the server with these certificates.

Certificate pairing rules: For each certificate item, provide either:

  • Inline PEM data using both cert and key or

  • File paths using both cert_file and key_file.

Mixing inline and file-based values within the same item is not supported.

Type: array<object>

Default: []

# Examples:
client_certs:
  - cert: foo
    key: bar


# ---

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

tls.client_certs[].cert

The plaintext certificate to use for TLS authentication. Must be paired with the corresponding private key in the key field when using inline PEM data for mTLS client certificates.

Type: string

Default: ""

tls.client_certs[].cert_file

The path to a file containing the certificate to use for TLS authentication. Must be paired with the corresponding private key file in the key_file field when using file-based configuration for mTLS client certificates.

Type: string

Default: ""

tls.client_certs[].key

Private key for mTLS client certificate as inline PEM data. Must correspond to the client certificate specified in the cert field. Use this field together with cert when providing certificate data inline rather than through files.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

tls.client_certs[].key_file

Path to private key file for mTLS client certificate in PEM format. Must correspond to the client certificate specified in the cert_file field. Use this field together with cert_file when loading certificate data from files.

Type: string

Default: ""

tls.client_certs[].password

The password to use for the private key (specified in the key or key_file fields), if it is password-protected. The PKCS#1 and PKCS#8 formats are supported. Supports environment variable interpolation for secure password management.

The pbeWithMD5AndDES-CBC algorithm is obsolete and not supported for the PKCS#8 format. This algorithm does not authenticate the ciphertext, making it vulnerable to padding oracle attacks that can let an attacker recover the plaintext.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

# Examples:
password: foo

# ---

password: ${KEY_PASSWORD}

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

tls.root_cas

Specify a root certificate authority to use (optional). This is a string that represents a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate. Use either this field for inline certificate data or root_cas_file for file-based certificate loading.

This field contains sensitive information that usually shouldn’t be added to a configuration directly. For more information, see Secrets.

Type: string

Default: ""

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

tls.root_cas_file

Specify the path to a root certificate authority file (optional). This is a file, often with a .pem extension, which contains a certificate chain from the parent-trusted root certificate, through possible intermediate signing certificates, to the host certificate. Use either this field for file-based certificate loading or root_cas for inline certificate data.

Type: string

Default: ""

# Examples:
root_cas_file: ./root_cas.pem

tls.skip_cert_verify

Whether to skip server-side certificate verification. Set to true only for testing environments as this reduces security by disabling certificate validation. When using self-signed certificates or in development, this may be necessary, but should never be used in production. Consider using root_cas or root_cas_file to specify trusted certificates instead of disabling verification entirely.

Type: bool

Default: false

uri

The connection URI for your graphing database. For more information, see Neo4j’s documentation.

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