Demo Logs

Generate fake log events, which can be useful for testing and demos

status: stable role: daemon role: sidecar delivery: at-least-once acknowledgements: no egress: stream state: stateless output: log previously known as: generator
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Generates fakes events useful for testing and demoing.

Alias

This component was previously called the generator source. Make sure to update your Vector configuration to accommodate the name change:

[sources.my_demo_logs_source]
+type = "demo_logs"
-type = "generator"

Configuration

Example configurations 

{
  "sources": {
    "my_source_id": {
      "type": "demo_logs",
      "format": "apache_common",
      "lines": [
        "line1"
      ]
    }
  }
}
[sources.my_source_id]
type = "demo_logs"
format = "apache_common"
lines = [ "line1" ]

---
sources:
  my_source_id:
    type: demo_logs
    format: apache_common
    lines:
      - line1

{
  "sources": {
    "my_source_id": {
      "type": "demo_logs",
      "count": 9223372036854776000,
      "format": "apache_common",
      "interval": 1,
      "lines": [
        "line1"
      ]
    }
  }
}
[sources.my_source_id]
type = "demo_logs"
count = 9_223_372_036_854_776_000
format = "apache_common"
interval = 1
lines = [ "line1" ]

---
sources:
  my_source_id:
    type: demo_logs
    count: 9223372036854776000
    format: apache_common
    interval: 1
    lines:
      - line1

count

optional uint

The total number of lines to output.

By default, the source continuously prints logs (infinitely).

default: 9.223372036854776e+18

decoding

optional object
Configures how events are decoded from raw bytes.

decoding.codec

optional string literal enum
The codec to use for decoding events.
Enum options
OptionDescription
bytesUses the raw bytes as-is.
gelfDecodes the raw bytes as a GELF message.
jsonDecodes the raw bytes as JSON.
native

Decodes the raw bytes as Vector’s native Protocol Buffers format.

This codec is experimental.

native_json

Decodes the raw bytes as Vector’s native JSON format.

This codec is experimental.

syslog

Decodes the raw bytes as a Syslog message.

Decodes either as the RFC 3164-style format (“old” style) or the RFC 5424-style format (“new” style, includes structured data).

default: bytes

format

required string literal enum
The format of the randomly generated output.
Examples 
"apache_common"
"apache_error"
"bsd_syslog"
"json"
"shuffle"
"syslog"
Enum options string literal
OptionDescription
apache_commonRandomly generated logs in Apache common format.
apache_errorRandomly generated logs in Apache error format.
bsd_syslogRandomly generated logs in Syslog format (RFC 3164).
jsonRandomly generated HTTP server logs in JSON format.
shuffleLines are chosen at random from the list specified using lines.
syslogRandomly generated logs in Syslog format (RFC 5424).

framing

optional object

Framing configuration.

Framing handles how events are separated when encoded in a raw byte form, where each event is a frame that must be prefixed, or delimited, in a way that marks where an event begins and ends within the byte stream.

framing.character_delimited

required object
Options for the character delimited decoder.
Relevant when: method = "character_delimited"
framing.character_delimited.delimiter
required uint
The character that delimits byte sequences.
framing.character_delimited.max_length
optional uint

The maximum length of the byte buffer.

This length does not include the trailing delimiter.

By default, there is no maximum length enforced. If events are malformed, this can lead to additional resource usage as events continue to be buffered in memory, and can potentially lead to memory exhaustion in extreme cases.

If there is a risk of processing malformed data, such as logs with user-controlled input, consider setting the maximum length to a reasonably large value as a safety net. This ensures that processing is not actually unbounded.

framing.method

optional string literal enum
The framing method.
Enum options
OptionDescription
bytesByte frames are passed through as-is according to the underlying I/O boundaries (for example, split between messages or stream segments).
character_delimitedByte frames which are delimited by a chosen character.
length_delimitedByte frames which are prefixed by an unsigned big-endian 32-bit integer indicating the length.
newline_delimitedByte frames which are delimited by a newline character.
octet_countingByte frames according to the octet counting format.
default: bytes

framing.newline_delimited

optional object
Options for the newline delimited decoder.
Relevant when: method = "newline_delimited"
framing.newline_delimited.max_length
optional uint

The maximum length of the byte buffer.

This length does not include the trailing delimiter.

By default, there is no maximum length enforced. If events are malformed, this can lead to additional resource usage as events continue to be buffered in memory, and can potentially lead to memory exhaustion in extreme cases.

If there is a risk of processing malformed data, such as logs with user-controlled input, consider setting the maximum length to a reasonably large value as a safety net. This ensures that processing is not actually unbounded.

framing.octet_counting

optional object
Options for the octet counting decoder.
Relevant when: method = "octet_counting"
framing.octet_counting.max_length
optional uint
The maximum length of the byte buffer.

interval

optional float

The amount of time, in seconds, to pause between each batch of output lines.

The default is one batch per second. To remove the delay and output batches as quickly as possible, set interval to 0.0.

Examples 
1
0.1
0.01
default: 1 (seconds)

lines

required [string]
The list of lines to output.
Array string literal
Examples 
[
  "line1",
  "line2"
]
Relevant when: format = "shuffle"

sequence

optional bool
If true, each output line starts with an increasing sequence number, beginning with 0.
default: false
Relevant when: format = "shuffle"

Outputs

<component_id>

Default output stream of the component. Use this component’s ID as an input to downstream transforms and sinks.

Output Data

Logs

Line

An individual event from a batch of events generated by vector for testing purposes.
Fields
source_type required string literal
The name of the source type.
Examples
demo_logs

Telemetry

Metrics

link

component_discarded_events_total

counter
The number of events dropped by this component.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
host optional
The hostname of the system Vector is running on.
pid optional
The process ID of the Vector instance.

component_errors_total

counter
The total number of errors encountered by this component.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
error_type
The type of the error
host optional
The hostname of the system Vector is running on.
pid optional
The process ID of the Vector instance.
stage
The stage within the component at which the error occurred.

component_received_bytes_total

counter
The number of raw bytes accepted by this component from source origins.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
container_name optional
The name of the container from which the data originated.
file optional
The file from which the data originated.
host optional
The hostname of the system Vector is running on.
mode optional
The connection mode used by the component.
peer_addr optional
The IP from which the data originated.
peer_path optional
The pathname from which the data originated.
pid optional
The process ID of the Vector instance.
pod_name optional
The name of the pod from which the data originated.
uri optional
The sanitized URI from which the data originated.

component_received_event_bytes_total

counter
The number of event bytes accepted by this component either from tagged origins like file and uri, or cumulatively from other origins.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
container_name optional
The name of the container from which the data originated.
file optional
The file from which the data originated.
host optional
The hostname of the system Vector is running on.
mode optional
The connection mode used by the component.
peer_addr optional
The IP from which the data originated.
peer_path optional
The pathname from which the data originated.
pid optional
The process ID of the Vector instance.
pod_name optional
The name of the pod from which the data originated.
uri optional
The sanitized URI from which the data originated.

component_received_events_count

histogram

A histogram of the number of events passed in each internal batch in Vector’s internal topology.

Note that this is separate than sink-level batching. It is mostly useful for low level debugging performance issues in Vector due to small internal batches.

component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
container_name optional
The name of the container from which the data originated.
file optional
The file from which the data originated.
host optional
The hostname of the system Vector is running on.
mode optional
The connection mode used by the component.
peer_addr optional
The IP from which the data originated.
peer_path optional
The pathname from which the data originated.
pid optional
The process ID of the Vector instance.
pod_name optional
The name of the pod from which the data originated.
uri optional
The sanitized URI from which the data originated.

component_received_events_total

counter
The number of events accepted by this component either from tagged origins like file and uri, or cumulatively from other origins.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
container_name optional
The name of the container from which the data originated.
file optional
The file from which the data originated.
host optional
The hostname of the system Vector is running on.
mode optional
The connection mode used by the component.
peer_addr optional
The IP from which the data originated.
peer_path optional
The pathname from which the data originated.
pid optional
The process ID of the Vector instance.
pod_name optional
The name of the pod from which the data originated.
uri optional
The sanitized URI from which the data originated.

component_sent_event_bytes_total

counter
The total number of event bytes emitted by this component.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
host optional
The hostname of the system Vector is running on.
output optional
The specific output of the component.
pid optional
The process ID of the Vector instance.

component_sent_events_total

counter
The total number of events emitted by this component.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
host optional
The hostname of the system Vector is running on.
output optional
The specific output of the component.
pid optional
The process ID of the Vector instance.

source_lag_time_seconds

histogram
The difference between the timestamp recorded in each event and the time when it was ingested, expressed as fractional seconds.
component_id
The Vector component ID.
component_kind
The Vector component kind.
component_name
Deprecated, use component_id instead. The value is the same as component_id.
component_type
The Vector component type.
host optional
The hostname of the system Vector is running on.
pid optional
The process ID of the Vector instance.

How it works

Context

By default, the demo_logs source augments events with helpful context keys.

State

This component is stateless, meaning its behavior is consistent across each input.
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