Update plugin docs

- Create separate files for each mixin
- Remove old "report" plugin docs

docs/extend/plugins.md

@@ -16,9 +16,59 @@ Plugins are discovered and loaded when the server is started.
 !!! info "Enable Plugin Support"
     To enable custom plugins, plugin support must be activated in the [server configuration](../start/config.md).
 
-Multiple plugins are supported:
+### Plugin Base Class
 
-- [Reporting plugins](./plugins/report.md)
+Custom plugins must inherit from the [IntegrationPluginBase class](https://github.com/inventree/InvenTree/blob/master/InvenTree/plugin/integration.py). Any plugins installed via the methods outlined above will be "discovered" when the InvenTree server launches.
-- [Barcode plugins](./plugins/barcode.md)
+
-- [Action plugins](./plugins/action.md)
+### Plugin Options
-- [Integration plugins](./plugins/integration.md)
+
+Some metadata options can be defined as constants in the plugins class
+
+``` python
+PLUGIN_SLUG = None  # Used in URLs, setting-names etc. when a unique slug as a reference is needed -> the plugin name is used if not set
+PLUGIN_TITLE = None  # A nice human friendly name for the plugin -> used in titles, as plugin name etc.
+
+AUTHOR = None  # Author of the plugin, git commit information is used if not present
+PUBLISH_DATE = None  # Publishing date of the plugin, git commit information is used if not present
+VERSION = None  # Version of the plugin
+WEBSITE = None  # Website for the plugin, developer etc. -> is shown in plugin overview if set
+```
+
+Refer to the [sample plugins](https://github.com/inventree/InvenTree/tree/master/InvenTree/plugin/samples) for further examples.
+
+### Plugin Config
+
+A *PluginConfig* database entry will be created for each plugin "discovered" when the server launches. This configuration entry is used to determine if a particular plugin is enabled.
+
+The configuration entries must be enabled via the [InvenTree admin interface](../settings/admin.md).
+
+!!! warning "Disabled by Default"
+    Newly discovered plugins are disabled by default, and must be manually enabled by an admin user
+
+### Plugin Mixins
+
+Common use cases are covered by pre-supplied modules in the form of mixins (similar to how [django](https://docs.djangoproject.com/en/stable/topics/class-based-views/mixins/) does it). Each mixin enables the integration into a specific area of InvenTree. Sometimes it also enhances the plugin with helper functions to supply often used functions out-of-the-box.
+
+Supported mixin classes are:
+
+- [ActionMixin](./plugins/action.md)
+- [APICallMixin](./plugins/api.md)
+- [AppMixin](./plugins/app.md)
+- [BarcodeMixin](./plugins/barcode.md)
+- [EventMixin](./plugins/event.md)
+- [NavigationMixin](./plugins/navigation.md)
+- [ScheduleMixin](./plugins/schedule.md)
+- [SettingsMixin](./plugins/settings.md)
+- [UrlsMixin](./plugins/urls.md)
+
+## Installing a Plugin
+
+Plugins can either be loaded from paths in the InvenTree install directory or as a plugin installed via pip. We recommend installation via pip as this enables hassle-free upgrades.
+
+For development new plugins can be placed ina a subdirectory in `src/InvenTree/plugins`. Built-In plugins ship in `src/InvenTree/plugin/builtin`. To achive full unit-testing for all mixins there are some sample implementations in `src/InvenTree/plugin/samples`. These are not loaded in production mode.
+
+### Plugin Installation File
+
+Plugins installation can be simplified by providing a list of plugins in a plugin configuration file. This file (by default, 'plugins.txt' in the same directory as the server configuration file) contains a list of required plugin packages.
+
+Plugins can be installed from this file by simply running the command `invoke plugins`.

docs/extend/plugins/action.md

@@ -2,7 +2,7 @@
 title: Action Plugins
 ---
 
-### Action Plugins
+## ActionMixin
 
 Arbitrary "actions" can be called by POSTing data to the `/api/action/` endpoint. The POST request must include the name of the action to be performed, and a matching ActionPlugin plugin must be loaded by the server. Arbitrary data can also be provided to the action plugin via the POST data:
 

docs/extend/plugins/app.md

@@ -0,0 +1,10 @@
+---
+title: App Mixin
+---
+
+## AppMixin
+
+If this mixin is added to a plugin the directory the plugin class is defined in is added to the list of `INSTALLED_APPS` in the InvenTree server configuration.
+
+!!! warning "Danger Zone"
+    Only use this mixin if you have an understanding of djangos [app system](https://docs.djangoproject.com/en/stable/ref/applications). Plugins with this mixin are deeply integrated into InvenTree and can cause difficult to reproduce or long-running errors. Use the built-in testing functions of django to make sure your code does not cause unwanted behaviour in InvenTree before releasing.

docs/extend/plugins/barcode.md

@@ -1,5 +1,5 @@
 ---
-title: Barcode Plugins
+title: Barcode Mixin
 ---
 
 ### Barcode Plugins

docs/extend/plugins/event.md

@@ -0,0 +1,3 @@
+---
+title: Event Mixin
+---

docs/extend/plugins/integration.md

@@ -24,12 +24,7 @@ WEBSITE = None  # Website for the plugin, developer etc. -> is shown in plugin o
 
 
 
-#### Installing a Plugin
+##
-
-Plugins can either be loaded from paths in the InvenTree install directory or as a plugin installed via pip. We recommend installation via pip as this enables hassle-free upgrades.
-
-For development new plugins can be placed ina a subdirectroy in `src/InvenTree/plugins`. Built-In plugins ship in `src/InvenTree/plugin/builtin`. To achive full unit-testing for all mixins there are some sample implementations in `src/InvenTree/plugin/samples`. These are not loaded in production mode.
-
 #### Mixins
 
 Common use cases are covered by pre-supplied modules in the form of mixins (similar to how [django](https://docs.djangoproject.com/en/stable/topics/class-based-views/mixins/) does it). Each mixin enables the integration into a specific area of InvenTree. Sometimes it also enhances the plugin with helper functions to supply often used functions out-of-the-box.

docs/extend/plugins/navigation.md

@@ -0,0 +1,25 @@
+---
+title: Navigation Mixin
+---
+
+## NavigationMixin
+
+Use the class constant `NAVIGATION` for a array of links that should be added to InvenTrees navigation header.  
+The array must contain at least one dict that at least define a name and a link for each element. The link must be formatted for a URL pattern name lookup - links to external sites are not possible directly. The optional icon must be a class reference to an icon (InvenTree ships with fontawesome 4 by default).
+
+``` python
+class MyNavigationPlugin(NavigationMixin, IntegrationPluginBase):
+
+    PLUGIN_NAME = "NavigationPlugin"
+
+    NAVIGATION = [
+        {'name': 'SampleIntegration', 'link': 'plugin:sample:hi', 'icon': 'fas fa-box'},
+    ]
+
+    NAVIGATION_TAB_NAME = "Sample Nav"
+    NAVIGATION_TAB_ICON = 'fas fa-plus'
+```
+
+The optional class constants `NAVIGATION_TAB_NAME` and `NAVIGATION_TAB_ICON` can be used to change the name and icon for the parent navigation node.
+
+

docs/extend/plugins/report.md

@@ -1,10 +0,0 @@
----
-title: Reporting Plugins
----
-
-### Reporting Plugins
-
-InvenTree can generate customized reports (for example stocktake information, packing lists, acceptance test reports, etc).
-
-!!! missing "TODO"
-	Include more information here on reporting plugins

docs/extend/plugins/schedule.md

@@ -0,0 +1,3 @@
+---
+title: Schedule Mixin
+---

docs/extend/plugins/settings.md

@@ -0,0 +1,48 @@
+---
+title: Settings Mixin
+---
+
+## SettingsMixin
+
+The *SettingsMixin* allows the plugin to save and load persistent settings to the database.
+
+- Plugin settings are stored against the individual plugin, and thus do not have to be unique
+- Plugin settings are stored using a "key:value" pair
+
+Use the class constant `SETTINGS` for a dict of settings that should be added as global database settings.  
+
+The dict must be formatted similar to the following sample. Take a look at the settings defined in `InvenTree.common.models.InvenTreeSetting` for all possible parameters.
+
+
+``` python
+class PluginWithSettings(SettingsMixin, IntegrationPluginBase):
+    
+    PLUGIN_NAME = "PluginWithSettings"
+    
+    SETTINGS = {
+        'API_ENABLE': {
+            'name': 'API Functionality',
+            'description': 'Enable remote API queries',
+            'validator': bool,
+            'default': True,
+        },
+        'API_KEY': {
+            'name': 'API Key',
+            'description': 'Security key for accessing remote API',
+            'default': '',
+        },
+        'API_URL': {
+            'name': _('API URL'),
+            'description': _('Base URL for remote server'),
+            'default': 'http://remote.url/api',
+        },
+    }
+```
+
+This mixin defines the helper functions `plugin.get_setting` and `plugin.set_seting` to access all plugin specific settings:
+
+```python
+api_url = self.get_setting('API_URL')
+```
+
+

docs/extend/plugins/urls.md

@@ -0,0 +1,23 @@
+---
+title: URLs Mixin
+---
+
+## UrlsMixin
+
+Use the class constant `URLS` for a array of URLs that should be added to InvenTrees URL paths or override the `plugin.setup_urls` function.  
+
+The array has to contain valid URL patterns as defined in the [django documentation](https://docs.djangoproject.com/en/stable/topics/http/urls/).
+
+``` python
+class MyUrlsPlugin(URLsMixin, IntegrationPluginBase):
+
+    PLUGIN_NAME = "UrlsMixin"
+
+    URLS = [
+        url(r'increase/(?P<location>\d+)/(?P<pk>\d+)/', self.view_increase, name='increase-level'),
+    ]
+```
+
+The URLs get exposed under `/plugin/{plugin.slug}/*` and get exposed to the template engine with the prefix `plugin:{plugin.slug}:` (for usage with the [url tag](https://docs.djangoproject.com/en/stable/ref/templates/builtins/#url)).
+
+

mkdocs.yml

@@ -111,10 +111,15 @@ nav:
     - Python Interface: extend/python.md
     - Plugins:
       - Overview: extend/plugins.md
-      - Reporting: extend/plugins/report.md
+      - Action Mixin: extend/plugins/action.md
-      - Barcode: extend/plugins/barcode.md
+      - API Mixin: extend/plugins/api.md
-      - Action: extend/plugins/action.md
+      - App Mixin: extend/plugins/app.md
-      - Integration: extend/plugins/integration.md
+      - Barcode Mixin: extend/plugins/barcode.md
+      - Event Mixin: extend/plugins/event.md
+      - Navigation Mixin: extend/plugins/navigation.md
+      - Schedule Mixin: extend/plugins/schedule.md
+      - Settings Mixin: extend/plugins/settings.md
+      - URL Mixin: extend/plugins/urls.md
     - Themes: extend/themes.md
     - Third-Party: extend/integrate.md
   - App: