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schema_registry_encode

EXPERIMENTAL

This component is experimental and therefore subject to change or removal outside of major version releases.

Automatically encodes and validates messages with schemas from a Confluent Schema Registry service.

Introduced in version 3.58.0.

# Common config fields, showing default values
label: ""
schema_registry_encode:
url: ""
subject: ""
refresh_period: 10m

Encodes messages automatically from schemas obtains from a Confluent Schema Registry service by polling the service for the latest schema version for target subjects.

If a message fails to encode under the schema then it will remain unchanged and the error can be caught using error handling methods outlined here.

Currently only Avro schemas are supported.

Avro JSON Format

By default this processor expects documents formatted as Avro JSON when encoding Avro schemas. In this format the value of a union is encoded in JSON as follows:

  • if its type is null, then it is encoded as a JSON null;
  • otherwise it is encoded as a JSON object with one name/value pair whose name is the type's name and whose value is the recursively encoded value. For Avro's named types (record, fixed or enum) the user-specified name is used, for other types the type name is used.

For example, the union schema ["null","string","Foo"], where Foo is a record name, would encode:

  • null as null;
  • the string "a" as {"string": "a"}; and
  • a Foo instance as {"Foo": {...}}, where {...} indicates the JSON encoding of a Foo instance.

However, it is possible to instead consume documents in raw JSON format (that match the schema) by setting the field avro_raw_json to true.

Fields

url

The base URL of the schema registry service.

Type: string

subject

The schema subject to derive schemas from. This field supports interpolation functions.

Type: string

# Examples

subject: foo

subject: ${! meta("kafka_topic") }

refresh_period

The period after which a schema is refreshed for each subject, this is done by polling the schema registry service.

Type: string
Default: "10m"

# Examples

refresh_period: 60s

refresh_period: 1h

avro_raw_json

Whether messages encoded in Avro format should be parsed as raw JSON documents rather than Avro JSON.

Type: bool
Default: false
Requires version 3.59.0 or newer

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

# 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 a password encrypted PEM block according to RFC 1423. Warning: Since it 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}