Logging

Dolos outputs logs through stdout. Internally, it uses a tracing mechanism that groups logs into hierarchical blocks called spans that holds data describing the context where the event occurred.

Depending on your use-case, the amount and detail of these logs might be overwhelming. Dolos provides a set of configuration values that allows you to opt-in into different levels of detail.

Log Levels

Dolos follows a very common convention around log levels. These levels describe discrete categories of decreasing severity.

level	description
`error`	unexpected errors, stuff that shouldn’t occur
`warn`	warning about things that are expected but require attention
`info`	normal operation events that are relevant for day-to-day operations
`debug`	normal operation events with a level of detail useful for debugging problems
`trace`	extreme level of detail, usually including data being processed

Sub-components

There are some sub-components within Dolos that are more verbose than others. By default, logs from these components are suppressed. You can opt-in to include them as needed:

component	description
tokio	The async runtime
pallas	Low-level Ouroboros interactions (mini-protocols, CBOR decoding)
grpc	The gRPC server (UTxO RPC)
trp	The Transaction Resolver Protocol server
minibf	The Mini-Blockfrost HTTP server
minikupo	The Mini-Kupo HTTP server
otlp	OpenTelemetry exporters
fjall	The Fjall storage engine

Configuration

The [logging] section within dolos.toml controls these options:

property	type	default
max_level	string	`"info"`
include_tokio	boolean	`false`
include_pallas	boolean	`false`
include_grpc	boolean	`false`
include_trp	boolean	`false`
include_minibf	boolean	`false`
include_minikupo	boolean	`false`
include_otlp	boolean	`false`
include_fjall	boolean	`false`

max_level: the maximum severity level of events to include in the output. By selecting a specific level, you include that level and every level of higher severity.
include_*: flags that indicate if the output should include logs from the corresponding sub-component.

All fields are optional. Omitted values use the defaults shown above.

Example:

[logging]
max_level = "debug"
include_pallas = true
include_grpc = true

You can find more detailed info about configuration in the configuration schema section.