Ballerina Log Package

The Log package is one of the standard library packages of the Ballerina language.

This package provides APIs to log information when running applications.

A sample log message logged from the foo module would look as follows:

time = 2021-05-12T11:20:29.362+05:30 level = ERROR module = myorg/foo message = "Something went wrong"

Log Levels

The log module provides APIs to log at four levels, which are DEBUG, ERROR, INFO, and WARN. By default, all log messages are logged to the console at the INFO level.

The log level can be configured via a Ballerina configuration file. To set the global log level, place the entry given below in the Config.toml file:

[ballerina.log]
level = "[LOG_LEVEL]"

Each module can also be assigned its own log level. To assign a log level to a module, provide the following entry in the Config.toml file:

[[ballerina.log.modules]]
name = "[ORG_NAME]/[MODULE_NAME]"
level = "[LOG_LEVEL]"

Log Output

Logs are written to the stderr stream by default.

To publish the logs to a file, redirect the stderr stream to a file as follows.

$ bal run program.bal 2> b7a-user.log

By default, logs are printed in the LogFmt format. To set the output format to JSON, place the entry given below in the Config.toml file.

[ballerina.log]
format = "json"

A sample log message logged from the foo module in JSON format would look as follows:

{"time":"2021-05-12T11:26:00.021+05:30", "level":"INFO", "module":"myorg/foo", "message":"Authenticating user"}

For more information go to the log package.

For example demonstrations of the usage, go to Ballerina By Examples.

Issues and Projects

Issues and Projects tabs are disabled for this repository as this is part of the Ballerina Standard Library. To report bugs, request new features, start new discussions, view project boards, etc. please visit Ballerina Standard Library parent repository.

This repository only contains the source code for the package.

Building from the Source

Setting Up the Prerequisites

Download and install Java SE Development Kit (JDK) version 11 (from one of the following locations).
- Oracle
- OpenJDK
  
  Note: Set the JAVA_HOME environment variable to the path name of the directory into which you installed JDK.

Export Github Personal access token with read package permissions as follows,

    export packageUser=<Username>
    export packagePAT=<Personal access token>

Building the Source

Execute the commands below to build from source.

To build the package:
```
./gradlew clean build
```
To run the tests:
```
./gradlew clean test
```

To run a group of tests

./gradlew clean test -Pgroups=<test_group_names>

To build the without the tests:
```
./gradlew clean build -x test
```
To debug package implementation:
```
./gradlew clean build -Pdebug=<port>
```

To debug with Ballerina language:

./gradlew clean build -PbalJavaDebug=<port>

Publish the generated artifacts to the local Ballerina central repository:
```
./gradlew clean build -PpublishToLocalCentral=true
```
Publish the generated artifacts to the Ballerina central repository:
```
./gradlew clean build -PpublishToCentral=true
```

Contributing to Ballerina

As an open source project, Ballerina welcomes contributions from the community.

For more information, go to the contribution guidelines.

Code of Conduct

All contributors are encouraged to read the Ballerina Code of Conduct.

Useful Links

Chat live with us via our Slack channel.
Post all technical questions on Stack Overflow with the #ballerina tag.

udda1996 / module-ballerina-log