mirror of https://github.com/deavmi/dlog.git
107 lines
3.3 KiB
Markdown
107 lines
3.3 KiB
Markdown
![](branding/logo.png)
|
|
|
|
dlog
|
|
====
|
|
|
|
**Simple and modular logging library**
|
|
|
|
`[2021-Dec-23 11:17:35.3527637] (source/dlog/testing/thing.d:12): This is a log message`
|
|
|
|
---
|
|
|
|
## Usage
|
|
|
|
We recommend you use [dub](http://code.dlang.org) to add dlog to your project as follows:
|
|
|
|
```
|
|
dub add dlog
|
|
```
|
|
|
|
[View on DUB](https://code.dlang.org/packages/dlog)
|
|
|
|
### Components
|
|
|
|
dlog is formed out of two main components:
|
|
|
|
1. `Logger`
|
|
* The logger contains the needed barebones for facilitating the actual logging of text
|
|
2. `MessageTransform`
|
|
* A MessageTransform is attached to a logger and performs manipulation on the text input into the logger for logging
|
|
* They may be chained as to perform multiple transformations in a stream-like fashion
|
|
|
|
### Quick start
|
|
|
|
If you want to immediately begin logging text usin the defaults and don't care about implementing your own transformations then you can
|
|
simply use the defaulkt logger as follows:
|
|
|
|
```d
|
|
import dlog;
|
|
|
|
Logger logger = new DefaultLogger();
|
|
|
|
|
|
logger.log("This is a log message");
|
|
logger.log(1);
|
|
logger.log(1==1);
|
|
logger.log([1,2,3]);
|
|
```
|
|
|
|
This will output the following:
|
|
|
|
```
|
|
[2021-Dec-23 11:17:35.3527637] (source/dlog/testing/thing.d:12): This is a log message
|
|
[2021-Dec-23 11:17:35.3527717] (source/dlog/testing/thing.d:13): 1
|
|
[2021-Dec-23 11:17:35.3527789] (source/dlog/testing/thing.d:14): true
|
|
[2021-Dec-23 11:17:35.3527871] (source/dlog/testing/thing.d:15): [1, 2, 3]
|
|
```
|
|
|
|
As you can see file and line numbering of where the `log()` function is called appears in the log message which can be quite helpful
|
|
for debugging.
|
|
|
|
### Custom loggers
|
|
|
|
Perhaps the default transformation, `DefaultTransform`, may not be what you want. Maybe you want the module name included in the logged
|
|
messages or perhaps don't want the date-and-timestamp included at all. All of this can be up to you if you choose to implement your own
|
|
message transform.
|
|
|
|
You will need to start off with a class that inherits from the `MessageTransform` class and then which overrides the `transform` method as shown below:
|
|
|
|
```d
|
|
import dlog;
|
|
|
|
public class CustomTranform : MessageTransform
|
|
{
|
|
public override string transform(string text, string[] context)
|
|
{
|
|
string transformed;
|
|
|
|
|
|
|
|
return transformed;
|
|
}
|
|
}
|
|
```
|
|
|
|
Additional information, besides the text being logged itself (this is the `string text` argument), comes in the form of a string array as `string[] context`
|
|
the contents of which are described below:
|
|
|
|
1. `context[0]`
|
|
* This contains `__FILE_FULL_PATH__` which is the full path (absolute) to the source file where `log()` was called
|
|
2. `context[1]`
|
|
* This contains `__FILE__` which is the path (starting at `source/` to the source file where `log()` was called
|
|
3. `context[2]`
|
|
* This contains a stringified version of `__LINE__` which is the line number of the call to `log()`
|
|
4. `context[3]`
|
|
* This contains `__MODULE__` which is the name of the module the call to `log()` appeared in
|
|
5. `context[4]`
|
|
* This contains `__FUNCTION__` which is the name of the function `log()` was called in
|
|
6. `context[5]`
|
|
* This contains `__PRETTY_FUNCTION__` which is the same as above but with type information
|
|
7. `context[5..X]`
|
|
* This contains optional extras that were set when the `log()` function was called with the `contextExtras` set
|
|
* Example: `log("Hello world", contextExtras=[this])`
|
|
|
|
## License
|
|
|
|
LGPLv2
|