> For the complete documentation index, see [llms.txt](https://docs.conanjs.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.conanjs.io/logging.md).

# Logging

## Introduction

Logging is built-in with ConanJs to provide you with an integrated platform so that you can:

* Log meaningful message easily
* Log what is happening internally in ConanJs
* Fine tune at runtime what should be logged.

ConanData and Asaps both produce ConanJs log messages out of the box.

{% hint style="success" %}
As of v1.0 dependency injection does not log anything at the moment, but this will be the case soon.
{% endhint %}

## Anatomy

A logging message has many attributes that are helpful to understand where the message comes from, its information, and also, to make easier to fine tune what should be logged out.

### Nature (Where?)

Indicates the nature of the source of this log message. There are seven natures:

| Name       | Source                                                                                                                             |
| ---------- | ---------------------------------------------------------------------------------------------------------------------------------- |
| **MAIN**   | The [main thread](/data/conan-state/life-cycle.md#the-main-thread) in a Conan state                                                |
| **META**   | The [meta flow](/data/conan-state/life-cycle.md#the-meta-flow) in a Conan state                                                    |
| **ASYNC**  | The [monitor thread](/data/conan-state/life-cycle.md#the-monitor-thread) in a Conan state                                          |
| **HELPER** | The [main thread](/data/conan-state/life-cycle.md#the-main-thread) in a Conan state (when the user decides to override the nature) |
| **ASAP**   | Log message from an [ASAP](/asaps.md).                                                                                             |
| **AUX**    | Derived from a Conan State that is created internally by the framework (you are likely to want to have this always turned off)     |

### Level (How important?)

There are 7 levels. In order of importance (from less important to more important):

* **DEBUG**
* **TRACE**
* **INFO**
* **MILESTONE**
* **WARN**
* **ERROR**

### shortDesc

A string message describing what is happening

### payload

Optionally, there can a payload that will also get logged out.

## Fine tuning Logging.

You can configure what to log at runtime. By default it gets log out everything that is:

**MAIN** and **MILESTONE**

To fine tune what gets logged out there are three main methods

#### updateLoggingFilter

Receives the current rules for logging, returns the new rules for logging

#### setLoggingFilter

Sets the logging rules

#### getLoggingFilter

Get the current rules.

## Demo

The following example illustrates how to change the logging levels at runtime

{% embed url="<https://codesandbox.io/s/2dqbx>" %}