Cloud

http_client

Available in: Cloud, Self-Managed

Sends messages to a HTTP server.

Common
Advanced

outputs:
  label: ""
  http_client:
    url: "" # No default (required)
    verb: POST
    headers: {}
    rate_limit: "" # No default (optional)
    timeout: 5s
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
      processors: [] # No default (optional)

# All configuration fields, showing default values
output:
  label: ""
  http_client:
    url: "" # No default (required)
    verb: POST
    headers: {}
    metadata:
      include_prefixes: []
      include_patterns: []
    dump_request_log_level: "" # Optional
    oauth:
      enabled: false
      consumer_key: "" # Optional
      consumer_secret: "" # Optional
      access_token: "" # Optional
      access_token_secret: "" # Optional
    oauth2:
      enabled: false
      client_key: "" # Optional
      client_secret: "" # Optional
      token_url: "" # Optional
      scopes: []
      endpoint_params: {}
    basic_auth:
      enabled: false
      username: "" # Optional
      password: "" # Optional
    jwt:
      enabled: false
      private_key_file: "" # Optional
      signing_method: "" # Optional
      claims: {}
      headers: {}
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    rate_limit: "" # No default (optional)
    timeout: 5s
    retry_period: 1s
    max_retry_backoff: 300s
    retries: 3
    backoff_on:
      - 429
    drop_on: []
    successful_on: []
    proxy_url: "" # No default (optional)
    batch_as_multipart: false
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: "" # Optional
      check: "" # Optional
      processors: [] # No default (optional)
    multipart: []

Message sends

The body of the request sent to the HTTP server is the raw contents of the message payload. If the message has multiple parts (is a batch), the request is sent according to RFC1341. To disable this behavior, set the batch_as_multipart field to false.

When message retries are exhausted, this output rejects a message. Typically, a pipeline then continues attempts to send the message until it succeeds, whilst applying back pressure.

Dynamic URL and header settings

You can set the url and headers values dynamically using function interpolations.

Performance

For improved performance, this output sends:

Multiple messages in parallel. Adjust the max_in_flight field value to tune the maximum number of in-flight messages (or message batches).
Messages as batches. You can configure batches at both input and output level. For more information, see Message Batching.

Fields

`backoff_on[]`

A list of status codes that indicate a request failure and trigger retries with an increasing backoff period between attempts.

Type: int

Default:

- 429

`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.password`

A password to authenticate with.

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

Type: string

Default: ""

`basic_auth.username`

A username to authenticate as.

Type: string

Default: ""

`batch_as_multipart`

When set to true, sends all message in a batch as a single request using RFC1341.

When set to false, sends messages in a batch as individual requests.

Type: bool

Default: false

`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.byte_size`

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

Type: int

Default: 0

`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.count`

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

Type: int

Default: 0

`batching.period`

The period 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.

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, and therefore splitting the batch into smaller batches using these processors is a no-op.

Type: processor

# Examples:
processors:
  - archive:
      format: concatenate


# ---

processors:
  - archive:
      format: lines


# ---

processors:
  - archive:
      format: json_array

`disable_http2`

Whether to disable HTTP/2. By default, HTTP/2 is enabled.

Type: bool

Default: false

`drop_on[]`

A list of status codes that indicate a request failure where the input should not attempt retries. This helps avoid unnecessary retries for requests that are unlikely to succeed.

In these cases, the request is dropped, but the message that triggered the request is retained.

Type: int

Default: []

`dump_request_log_level`

EXPERIMENTAL: Set the logging level for the request and response payloads of each HTTP request.

Type: string

Default: ""

Options: TRACE, DEBUG, INFO, WARN, ERROR, FATAL, ``

`follow_redirects`

Whether or not to transparently follow redirects, i.e. responses with 300-399 status codes. If disabled, the response message will contain the body, status, and headers from the redirect response and the processor will not make a request to the URL set in the Location header of the response.

Type: bool

Default: true

`headers`

A map of headers to add to the request. This field supports interpolation functions.

Type: string

Default: {}

# Examples:
headers:
  Content-Type: application/octet-stream
  traceparent: ${! tracing_span().traceparent }

`jwt`

Beta

Configure JSON Web Token (JWT) authentication. This feature is in beta and may change in future releases. JWT tokens provide secure, stateless authentication between services.

Type: object

`jwt.claims`

A value used to identify the claims that issued the JWT.

Type: object

Default: {}

`jwt.enabled`

Whether to use JWT authentication in requests.

Type: bool

Default: false

`jwt.headers`

Additional key-value pairs to include in the JWT header (optional). These headers provide extra metadata for JWT processing.

Type: object

Default: {}

`jwt.private_key_file`

Path to a file containing the PEM-encoded private key using PKCS#1 or PKCS#8 format. The private key must be compatible with the algorithm specified in the signing_method field.

Type: string

Default: ""

`jwt.signing_method`

The cryptographic algorithm used to sign the JWT token. Supported algorithms include RS256, RS384, RS512, and EdDSA. This algorithm must be compatible with the private key specified in the private_key_file field.

Type: string

Default: ""

`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

`max_retry_backoff`

The maximum period to wait between failed requests.

Type: string

Default: 300s

`metadata`

Specify matching rules that determine which metadata keys to add to the HTTP request as headers (optional).

Type: object

`metadata.include_patterns[]`

Provide a list of explicit metadata key regular expression (re2) patterns to match against.

Type: array

Default: []

# Examples:
include_patterns:
  - .*

# ---

include_patterns:
  - _timestamp_unix$

`metadata.include_prefixes[]`

Provide a list of explicit metadata key prefixes to match against.

Type: array

Default: []

# Examples:
include_prefixes:
  - foo_
  - bar_

# ---

include_prefixes:
  - kafka_

# ---

include_prefixes:
  - content-

`multipart[]`

EXPERIMENTAL: Create explicit multipart HTTP requests by specifying an array of parts to add to a request. Each part consists of content headers and a data field, which can be populated dynamically.

If populated, this field overrides the default request creation behavior.

Type: object

Default: []

`multipart[].body`

The body of the individual message part.

This field supports interpolation functions.

Type: string

Default: ""

# Examples:
body: ${! this.data.part1 }

`multipart[].content_disposition`

The content disposition of the individual message part.

This field supports interpolation functions.

Type: string

Default: ""

# Examples:
content_disposition: form-data; name="bin"; filename='${! @AttachmentName }

`multipart[].content_type`

The content type of the individual message part.

This field supports interpolation functions.

Type: string

Default: ""

# Examples:
content_type: application/bin

`oauth`

Configure OAuth version 1.0 authentication for secure API access.

Type: object

`oauth.access_token`

The value used to gain access to the protected resources on behalf of the user.

Type: string

Default: ""

`oauth.access_token_secret`

The secret that establishes ownership of the oauth.access_token in OAuth 1.0 authentication.

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

Type: string

Default: ""

`oauth.consumer_key`

A value used to identify the client to the service provider.

Type: string

Default: ""

`oauth.consumer_secret`

The secret that establishes ownership of the consumer key in OAuth 1.0 authentication.

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

Type: string

Default: ""

`oauth.enabled`

Whether to use OAuth version 1 in requests.

Type: bool

Default: false

`oauth2`

Allows you to specify open authentication using OAuth version 2 and the client credentials token flow.

Type: object

`oauth2.client_key`

A value used to identify the client to the token provider.

Type: string

Default: ""

`oauth2.client_secret`

The secret used to establish ownership of the client key.

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

Type: string

Default: ""

`oauth2.enabled`

Whether to use OAuth version 2 in requests.

Type: bool

Default: false

`oauth2.endpoint_params`

A list of endpoint parameters specified as arrays of strings (optional).

Type: object

Default: {}

# Examples:
endpoint_params:
  bar:
    - woof
  foo:
    - meow
    - quack

`oauth2.scopes[]`

A list of requested permissions (optional).

Type: array

Default: []

`oauth2.token_url`

The URL of the token provider.

Type: string

Default: ""

`proxy_url`

A HTTP proxy URL (optional).

Type: string

`rate_limit`

A rate limit to throttle requests by (optional).

Type: string

`retries`

The maximum number of retry attempts to make.

Type: int

Default: 3

`retry_period`

The initial period to wait between failed requests before retrying.

Type: string

Default: 1s

`successful_on[]`

A list of HTTP status codes that should be considered as successful, even if they are not 2XX codes. This is useful for handling cases where non-2XX codes indicate that the request was processed successfully, such as 303 See Other or 409 Conflict.

By default, all 2XX codes are considered successful unless they are specified in backoff_on or drop_on fields.

Type: int

Default: []

`timeout`

A static timeout to apply to requests.

Type: string

Default: 5s

`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 enabled to enable TLS, 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.

You must set tls.enabled: true for the client certificates to take effect.

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: object

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[].cert_file`

The path of a certificate to use.

Type: string

Default: ""

`tls.client_certs[].key`

A plain text certificate key to use.

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

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.

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

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.enabled`

Whether custom TLS settings are enabled.

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 Manage Secrets before adding it to your configuration.

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

`url`

The URL to connect to. This field supports interpolation functions.

Type: string

`verb`

A verb to connect with.

Type: string

Default: POST

# Examples:
verb: POST

# ---

verb: GET

# ---

verb: DELETE

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http_client

Message sends

Dynamic URL and header settings

Performance

Fields

backoff_on[]

basic_auth

basic_auth.enabled

basic_auth.password

basic_auth.username

batch_as_multipart

batching

batching.byte_size

batching.check

batching.count

batching.period

batching.processors[]

disable_http2

drop_on[]

dump_request_log_level

follow_redirects

headers

jwt

jwt.claims

jwt.enabled

jwt.headers

jwt.private_key_file

jwt.signing_method

max_in_flight

max_retry_backoff

metadata

metadata.include_patterns[]

metadata.include_prefixes[]

multipart[]

multipart[].body

multipart[].content_disposition

multipart[].content_type

oauth

oauth.access_token

oauth.access_token_secret

oauth.consumer_key

oauth.consumer_secret

oauth.enabled

oauth2

oauth2.client_key

oauth2.client_secret

oauth2.enabled

oauth2.endpoint_params

oauth2.scopes[]

oauth2.token_url

proxy_url

rate_limit

retries

retry_period

successful_on[]

timeout

tls

tls.client_certs[]

tls.client_certs[].cert

tls.client_certs[].cert_file

tls.client_certs[].key

tls.client_certs[].key_file

tls.client_certs[].password

tls.enable_renegotiation

tls.enabled

tls.root_cas

tls.root_cas_file

tls.skip_cert_verify

url

verb

Simple online edits

Contribution guide

`backoff_on[]`

`basic_auth`

`basic_auth.enabled`

`basic_auth.password`

`basic_auth.username`

`batch_as_multipart`

`batching`

`batching.byte_size`

`batching.check`

`batching.count`

`batching.period`

`batching.processors[]`

`disable_http2`

`drop_on[]`

`dump_request_log_level`

`follow_redirects`

`headers`

`jwt`

`jwt.claims`

`jwt.enabled`

`jwt.headers`

`jwt.private_key_file`

`jwt.signing_method`

`max_in_flight`

`max_retry_backoff`

`metadata`

`metadata.include_patterns[]`

`metadata.include_prefixes[]`

`multipart[]`

`multipart[].body`

`multipart[].content_disposition`

`multipart[].content_type`

`oauth`

`oauth.access_token`

`oauth.access_token_secret`

`oauth.consumer_key`

`oauth.consumer_secret`

`oauth.enabled`

`oauth2`

`oauth2.client_key`

`oauth2.client_secret`

`oauth2.enabled`

`oauth2.endpoint_params`

`oauth2.scopes[]`

`oauth2.token_url`

`proxy_url`

`rate_limit`

`retries`

`retry_period`

`successful_on[]`

`timeout`

`tls`

`tls.client_certs[]`

`tls.client_certs[].cert`

`tls.client_certs[].cert_file`

`tls.client_certs[].key`

`tls.client_certs[].key_file`

`tls.client_certs[].password`

`tls.enable_renegotiation`

`tls.enabled`

`tls.root_cas`

`tls.root_cas_file`

`tls.skip_cert_verify`

`url`

`verb`