* plugin/metadata: add metadata plugin * plugin/metadata: Add MD struct, refactor code, fix doc * plugin/metadata: simplify metadata key * plugin/metadata: improve setup_test * Support of metadata by rewrite plugin. Move calculated variables to metadata. * Move variables from metadata to pkg, add UTs, READMEs change, metadata small fixes * Add client port validation to variables_test * plugin/metadata: improve README * plugin/metadata: rename methods * plugin/metadata: Update Metadataer interface, update doc, cosmetic code changes * plugin/metadata: move colllisions check to OnStartup(). Fix default variables metadataer. * plugin/metadata: Fix comment for method setValue * plugin/metadata: change variables order to fix linter warning * plugin/metadata: rename Metadataer to Provider
Resolves: #1313
Resolves: #1307
* Add processing mode * Add processing mode * Update UTs * Update README.md * Change to use the constant Stop * Fix README per review comments
* Rename middleware to plugin first pass; mostly used 'sed', few spots where I manually changed text. This still builds a coredns binary. * fmt error * Rename AddMiddleware to AddPlugin * Readd AddMiddleware to remain backwards compat