A key feature of WeeWX is its ability to be extended by installing 3rd party extensions. Extensions are a way to package one or more customizations so that they can be installed and distributed as a functional group.
Customizations typically fall into one of these categories:
- search list extension
Take a look at the WeeWX wiki for a sampling of some of the extensions that are available.
Creating an extension¶
Now that you have made some customizations, you might want to share those changes with other WeeWX users. Put your customizations into an extension to make installation, removal, and distribution easier.
Here are a few guidelines for creating extensions:
Extensions should not modify or depend upon existing skins. An extension should include its own, standalone skin to illustrate any templates, search list extension, or generator features.
Extensions should not modify the database schemas. If it requires data not found in the default databases, an extension should provide its own database and schema.
Although one extension might use another extension, take care to write the dependent extension so that it fails gracefully. For example, a skin might use data from the forecast extension, but what happens if the forecast extension is not installed? Make the skin display a message about "forecast not installed" but otherwise continue to function.
Packaging an extension¶
The structure of an extension mirrors that of WeeWX itself. If the
customizations include a skin, the extension will have a
skins directory. If
the customizations include python code, the extension will have a
Each extension should also include:
readme.md- a summary of what the extension does, a list of pre-requisites (if any), and instructions for installing the extension manually
changelog- an enumeration of changes in each release
install.py- python code used by the WeeWX
For example, here is the structure of an extension called
installs a skin called
Basic. You can find it in the
│ ├── en.conf
│ └── fr.conf
Here is the structure of an extension called
xstats, which implements a search
list extension, as well as a simple skin. You can also find it in the
│ └── user
│ └── xstats.py
To distribute an extension, simply create a compressed archive of the extension directory.
For example, create the compressed archive for the
tar cvfz basic.tar.gz basic
Once an extension has been packaged, it can be installed using
weectl extension install EXTENSION-LOCATION
Whenever possible, an extension should just work, with a minimum of input from
the user. At the same time, parameters for the most frequently requested options
should be easily accessible and easy to modify. For skins, this might mean
parameterizing strings into
[Labels] for easier customization. Or it might
mean providing parameters in
[Extras] to control skin behavior or to
Some parameters must be specified, and no default value would be appropriate. For example, an uploader may require a username and password, or a driver might require a serial number or IP address. In these cases, use a default value in the configuration that will obviously require modification. The username might default to REPLACE_ME. Also be sure to add a log entry that indicates the feature is disabled until the value has been specified.
In the case of drivers, use the configuration editor to prompt for this type of required value.