Merge ~mthaddon/charm-k8s-ingress/+git/charm-k8s-ingress:document-init-requires into charm-k8s-ingress:master

[Tom Haddon]

Clarify that the IngressRequires class must be instantiated in __init__

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[Benjamin Allot (ballot)]

+1

review: Approve

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This merge proposal is being monitored by mergebot. Change the status to Approved to merge.

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FAILED: Continuous integration, rev:ce0d11e1c9250d3af4c288d341aa47a019426404
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review: Needs Fixing (continuous-integration)

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PASSED: Continuous integration, rev:eda7700ea14993c9a3c361d19bb4930164e88c27
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Executed test runs:
    SUCCESS: https://jenkins.canonical.com/is/job/lp-charm-test/99/
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review: Approve (continuous-integration)

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Change successfully merged at revision 4b507f07402a1ac49c761705b3622c296965ba21

diff --git a/lib/charms/nginx_ingress_integrator/v0/ingress.py b/lib/charms/nginx_ingress_integrator/v0/ingress.py
index 4d98ee5..780458e 100644
--- a/lib/charms/nginx_ingress_integrator/v0/ingress.py
+++ b/lib/charms/nginx_ingress_integrator/v0/ingress.py
@@ -41,6 +41,11 @@ requires:
   ingress:
     interface: ingress
 ```
+You _must_ register the IngressRequires class as part of the `__init__` method
+rather than, for instance, a config-changed event handler. This is because
+doing so won't get the current relation changed event, because it wasn't
+registered to handle the event (because it wasn't created in `__init__` when
+the event was fired).
 """
 
 import logging
@@ -57,7 +62,7 @@ LIBAPI = 0
 
 # Increment this PATCH version before using `charmcraft publish-lib` or reset
 # to 0 if you are raising the major API version
-LIBPATCH = 7
+LIBPATCH = 8
 
 logger = logging.getLogger(__name__)