Before this changed we unconditionally fetched the MimeType. On Some
backends like s3 and swift this takes an extra transaction which meant
that `lsf` on those backends was needlessly slow.
This adds an internal option so `lsf` can declare whether it wants
MimeTypes or not depending on whether the user asked for them and an
external flag `--no-mimetype` for `lsjson`.
See: https://forum.rclone.org/t/reliably-setup-incremental-updates/14006/8
- Change rclone/fs interfaces to accept context.Context
- Update interface implementations to use context.Context
- Change top level usage to propagate context to lover level functions
Context propagation is needed for stopping transfers and passing other
request-scoped values.
This unifies the 3 methods of reading config
* command line
* environment variable
* config file
And allows them all to be configured in all places. This is done by
making the []fs.Option in the backend registration be the master
source of what the backend options are.
The backend changes are:
* Use the new configmap.Mapper parameter
* Use configstruct to parse it into an Options struct
* Add all config to []fs.Option including defaults and help
* Remove all uses of pflag
* Remove all uses of config.FileGet
The purpose of this is to make it easier to maintain and eventually to
allow the rclone backends to be re-used in other projects without
having to use the rclone configuration system.
The new code layout is documented in CONTRIBUTING.
