Http Client

Sends messages to an HTTP server.

Common

# Common config fields, showing default values
output:
  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: ""

Advanced

# All config fields, showing default values
output:
  label: ""
  http_client:
    url: "" # No default (required)
    verb: POST
    headers: {}
    metadata:
      include_prefixes: []
      include_patterns: []
    dump_request_log_level: ""
    oauth:
      enabled: false
      consumer_key: ""
      consumer_secret: ""
      access_token: ""
      access_token_secret: ""
    oauth2:
      enabled: false
      client_key: ""
      client_secret: ""
      token_url: ""
      scopes: []
      endpoint_params: {}
    basic_auth:
      enabled: false
      username: ""
      password: ""
    jwt:
      enabled: false
      private_key_file: ""
      signing_method: ""
      claims: {}
      headers: {}
    tls:
      enabled: false
      skip_cert_verify: false
      enable_renegotiation: false
      root_cas: ""
      root_cas_file: ""
      client_certs: []
    extract_headers:
      include_prefixes: []
      include_patterns: []
    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
    propagate_response: false
    max_in_flight: 64
    batching:
      count: 0
      byte_size: 0
      period: ""
      check: ""
      processors: [] # No default (optional)
    multipart: []

When the number of retries expires the output will reject the message, the behavior after this will depend on the pipeline but usually this simply means the send is attempted again until successful whilst applying back pressure.

The URL and header values of this type can be dynamically set using function interpolations.

The body of the HTTP request is the raw contents of the message payload. If the message has multiple parts (is a batch) the request will be sent according to RFC1341. This behavior can be disabled by setting the field batch_as_multipart to false.

Propagating Responses

It’s possible to propagate the response from each HTTP request back to the input source by setting propagate_response to true. Only inputs that support synchronous responses are able to make use of these propagated responses.

Performance

This output benefits from sending multiple messages in flight in parallel for improved performance. You can tune the max number of in flight messages (or message batches) with the field max_in_flight.

This output benefits from sending messages as a batch for improved performance. Batches can be formed at both the input and output level.

Fields

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

headers

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

Type: object
Default: {}

# Examples

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

metadata

Specify optional matching rules to determine which metadata keys should be added to the HTTP request as headers.

Type: object

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-

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$

dump_request_log_level

Optionally set a level at which the request and response payload of each request made will be logged.

Type: string
Default: ""
Options: TRACE, DEBUG, INFO, WARN, ERROR, FATAL, ``.

oauth

Allows you to specify open authentication via OAuth version 1.

Type: object

oauth.enabled

Whether to use OAuth version 1 in requests.

Type: bool
Default: false

oauth.consumer_key

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

Type: string
Default: ""

oauth.consumer_secret

A secret used to establish ownership of the consumer key.

Type: string
Default: ""

oauth.access_token

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

Type: string
Default: ""

oauth.access_token_secret

A secret provided in order to establish ownership of a given access token.

Type: string
Default: ""

oauth2

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

Type: object

oauth2.enabled

Whether to use OAuth version 2 in requests.

Type: bool
Default: false

oauth2.client_key

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

Type: string
Default: ""

oauth2.client_secret

A secret used to establish ownership of the client key.

Type: string
Default: ""

oauth2.token_url

The URL of the token provider.

Type: string
Default: ""

oauth2.scopes

A list of optional requested permissions.

Type: array
Default: []

oauth2.endpoint_params

A list of optional endpoint parameters, values should be arrays of strings.

Type: object
Default: {}

# Examples

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

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: ""

jwt

Allows you to specify JWT authentication.

Type: object

jwt.enabled

Whether to use JWT authentication in requests.

Type: bool
Default: false

jwt.private_key_file

A file with the PEM encoded via PKCS1 or PKCS8 as private key.

Type: string
Default: ""

jwt.signing_method

A method used to sign the token such as RS256, RS384, RS512 or EdDSA.

Type: string
Default: ""

jwt.claims

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

Type: object
Default: {}

jwt.headers

Add optional key/value headers to the JWT.

Type: object
Default: {}

tls

Custom TLS settings can be used to override system defaults.

Type: object

tls.enabled

Whether custom TLS settings are enabled.

Type: bool
Default: false

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

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. 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

extract_headers

Specify which response headers should be added to resulting synchronous response messages as metadata. Header keys are lowercased before matching, so ensure that your patterns target lowercased versions of the header keys that you expect. This field is not applicable unless propagate_response is set to true.

Type: object

extract_headers.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-

extract_headers.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$

rate_limit

An optional rate limit to throttle requests by.

Type: string

timeout

A static timeout to apply to requests.

Type: string
Default: "5s"

retry_period

The base period to wait between failed requests.

Type: string
Default: "1s"

max_retry_backoff

The maximum period to wait between failed requests.

Type: string
Default: "300s"

retries

The maximum number of retry attempts to make.

Type: int
Default: 3

backoff_on

A list of status codes whereby the request should be considered to have failed and retries should be attempted, but the period between them should be increased gradually.

Type: array
Default: [429]

drop_on

A list of status codes whereby the request should be considered to have failed but retries should not be attempted. This is useful for preventing wasted retries for requests that will never succeed. Note that with these status codes the request is dropped, but message that caused the request will not be dropped.

Type: array
Default: []

successful_on

A list of status codes whereby the attempt should be considered successful, this is useful for dropping requests that return non-2XX codes indicating that the message has been dealt with, such as a 303 See Other or a 409 Conflict. All 2XX codes are considered successful unless they are present within backoff_on or drop_on, regardless of this field.

Type: array
Default: []

proxy_url

An optional HTTP proxy URL.

Type: string

batch_as_multipart

Send message batches as a single request using RFC1341. If disabled messages in batches will be sent as individual requests.

Type: bool
Default: false

propagate_response

Whether responses from the server should be propagated back to the input.

Type: bool
Default: false

max_in_flight

The maximum number of parallel message batches to have in flight at any given time.

Type: int
Default: 64

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

multipart

Create explicit multipart HTTP requests by specifying an array of parts to add to the request, each part specified consists of content headers and a data field that can be populated dynamically. If this field is populated it will override the default request creation behavior.

Type: array
Default: []

multipart[].content_type

The content type of the individual message part. This field supports interpolation functions

Type: string
Default: ""

# Examples

content_type: application/bin

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[].body

The body of the individual message part. This field supports interpolation functions.

Type: string
Default: ""

# Examples

body: ${! this.data.part1 }