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The new locations will replace the current HTTP location of InCommon production metadata:
- http://wayf.incommonfederation.org/InCommon/InCommon-metadata.xml (legacy)
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In the best possible world, a deployment would configure itself to refresh its metadata store from the production metadata aggregate and that would be the end of it. The problem is that metadata aggregates are brittle by their very nature: , that is, a small change to metadata may have unexpected effects downstream. If this happens, a deployment can “fall back” to a previous version of metadata that is known not to cause the problemto be backward compatible.
Fallback Metadata Aggregate
The As suggested in the previous section, the fallback metadata aggregate comes into play when a breaking change is inadvertently introduced into InCommon metadata. When a change is made to the production metadata aggregate, and that change breaks a downstream metadata process, an affected deployment can temporarily migrate to the fallback metadata aggregate. This gives the deployment time to adjust to the breaking change.
The fallback metadata aggregate is transient in the sense that backward compatibility is provided for a limited, predetermined period of time. This forces deployments to adjust to breaking changes to production metadata albeit in a controlled environment.
Preview Metadata Aggregate
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