Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

config: Do not modify the structure of opaque config #7935

Closed
wants to merge 4 commits into from
Closed

config: Do not modify the structure of opaque config #7935

wants to merge 4 commits into from

Commits on May 27, 2020

  1. config: add HookWeakDecodeFromSlice 

    Currently opaque config blocks (config entries, and CA provider config) are
modified by PatchSliceOfMaps, making it impossible for these opaque
config sections to contain slices of maps.

In order to fix this problem, any lazy-decoding of these blocks needs to support
weak decoding of []map[string]interface{} to a struct type before
PatchSliceOfMaps is replaces. This is necessary because these config
blobs are persisted, and during an upgrade an older version of Consul
could read one of the new configuration values, which would cause an error.

To support the upgrade path, this commit first introduces the new hooks
for weak decoding of []map[string]interface{} and uses them only in the
lazy-decode paths. That way, in a future release, new style
configuration will be supported by the older version of Consul.

This decode hook has a number of advantages:

1. It no longer panics. It allows mapstructure to report the error
2. It no longer requires the user to declare which fields are slices of
   structs. It can deduce that information from the 'to' value.
3. It will make it possible to preserve opaque configuration, allowing
   for structured opaque config.
    @dnephin
    dnephin committed May 27, 2020
    Configuration menu
    Copy the full SHA
    8844d8d View commit details
    Browse the repository at this point in the history

  2. Add decode hooks to all lazy-decode parse functions 

    So that if they encounter config accepted by a newer version of Consul
they will know how to handle it.
    @dnephin
    dnephin committed May 27, 2020
    Configuration menu
    Copy the full SHA
    7e7a67b View commit details
    Browse the repository at this point in the history

  3. config: Use HookWeakDecodeFromSlice in place of PatchSliceOfMaps

    @dnephin
    dnephin committed May 27, 2020
    Configuration menu
    Copy the full SHA
    09f5c48 View commit details
    Browse the repository at this point in the history

  4. config: Do not modify the structure of opaque config 

    HCL and JSON config may have different structures. With this change the
opaque configuration will not be modified. When the config is
deserialized the same hook is used to handle this difference in
structure.
    @dnephin
    dnephin committed May 27, 2020
    Configuration menu
    Copy the full SHA
    e11c27a View commit details
    Browse the repository at this point in the history