title: SourceObject
---
summary: The basic interface of all source objects.
---
module: lektor.db
---
type: class
---
body:

Source objects is the common interface for all things that come out of the
database.  There are two types of source objects:

* [Records :ref](../record/) which are pages and attachments from the
  `contents/` folder.
* [Assets :ref](../asset/) which are files and directories from the
  `assets/` folder.

Whatever object you have in hands that comes from the database, they will
at least provide a minimal useful set of API methods and properties.

Plugins can subclass source objects to come up with their own source
objects if needed.  In addition to that there is a special source object
called the `VirtualSourceObject` which is more useful for plugin usage.

## Virtual Source Objects

Most plugins will not have source objects that actually originate on the
file system.  This means that their "source" is entirely virtual.  Because
this is a very common situation there is a base class, the
`VirtualSourceObject` which plugins can subclass.  The constructor takes one
argument which is the parent source object the virtual source lives below.

```python
from lektor.sourceobj import VirtualSourceObject

class Source(VirtualSourceObject):

    @property
    def source_content(self):
        with open(self.parent.source_filename) as f:
            return f.read().decode('utf-8')

    @property
    def url_path(self):
        return self.parent.url_path + 'source.txt'
```

For more information see [add-build-program
:ref](../../environment/add-build-program/).