Introduce Policies-Service (#5716)

* add policies service
add policies proxy middleware
add policies event service
add policies grpc service
prepare ci and git environments (ci, make, readme, doc)

* add webfinger to the drone conf

* fix docs
remove not used virus scan postprocessing step

* relocate example rego file
implicitly enable and disable proxy and postprocessing policy checking by setting the query.
update configuration descriptions

* move policies
update readme

* use converter func to convert pp environment to actual environment
expose and test custom rego functions
add engine unit tests
add opa unit tests
update policies readme

Co-authored-by: Martin <github@diemattels.at>

* relocate sample policies to the deployments folder
change and document policies service port

* update index.md and small fix

* add health command
add version command
add debug server

---------

Co-authored-by: Martin <github@diemattels.at>

go.mod

@@ -13,6 +13,7 @@ require (
 	github.com/cs3org/go-cs3apis v0.0.0-20221012090518-ef2996678965
 	github.com/cs3org/reva/v2 v2.12.1-0.20230313151335-4339b8ab4759
 	github.com/disintegration/imaging v1.6.2
+	github.com/gabriel-vasile/mimetype v1.4.1
 	github.com/ggwhite/go-masker v1.0.9
 	github.com/go-chi/chi/v5 v5.0.8
 	github.com/go-chi/cors v1.2.1
@@ -59,6 +60,7 @@ require (
 	github.com/onsi/ginkgo v1.16.5
 	github.com/onsi/ginkgo/v2 v2.9.1
 	github.com/onsi/gomega v1.27.4
+	github.com/open-policy-agent/opa v0.50.0
 	github.com/orcaman/concurrent-map v1.0.0
 	github.com/owncloud/libre-graph-api-go v1.0.2-0.20230309112802-ff71ba8c90aa
 	github.com/pkg/errors v0.9.1
@@ -105,9 +107,11 @@ require (
 	github.com/Masterminds/goutils v1.1.1 // indirect
 	github.com/Masterminds/sprig v2.22.0+incompatible // indirect
 	github.com/Microsoft/go-winio v0.6.0 // indirect
+	github.com/OneOfOne/xxhash v1.2.8 // indirect
 	github.com/ProtonMail/go-crypto v0.0.0-20220930113650-c6815a8c17ad // indirect
 	github.com/RoaringBitmap/roaring v0.9.4 // indirect
 	github.com/acomagu/bufpipe v1.0.3 // indirect
+	github.com/agnivade/levenshtein v1.1.1 // indirect
 	github.com/ajg/form v1.5.1 // indirect
 	github.com/alexedwards/argon2id v0.0.0-20211130144151-3585854a6387 // indirect
 	github.com/amoghe/go-crypt v0.0.0-20220222110647-20eada5f5964 // indirect
@@ -159,10 +163,10 @@ require (
 	github.com/emvi/iso-639-1 v1.0.1 // indirect
 	github.com/evanphx/json-patch/v5 v5.5.0 // indirect
 	github.com/fatih/color v1.13.0 // indirect
-	github.com/felixge/httpsnoop v1.0.1 // indirect
-	github.com/fsnotify/fsnotify v1.5.4 // indirect
-	github.com/gabriel-vasile/mimetype v1.4.1 // indirect
+	github.com/felixge/httpsnoop v1.0.3 // indirect
+	github.com/fsnotify/fsnotify v1.6.0 // indirect
 	github.com/gdexlab/go-render v1.0.1 // indirect
+	github.com/ghodss/yaml v1.0.0 // indirect
 	github.com/go-acme/lego/v4 v4.4.0 // indirect
 	github.com/go-asn1-ber/asn1-ber v1.5.4 // indirect
 	github.com/go-git/gcfg v1.5.0 // indirect
@@ -175,6 +179,7 @@ require (
 	github.com/go-redis/redis/v8 v8.11.5 // indirect
 	github.com/go-sql-driver/mysql v1.6.0 // indirect
 	github.com/go-task/slim-sprig v0.0.0-20210107165309-348f09dbbbc0 // indirect
+	github.com/gobwas/glob v0.2.3 // indirect
 	github.com/gobwas/httphead v0.1.0 // indirect
 	github.com/gobwas/pool v0.2.1 // indirect
 	github.com/gobwas/ws v1.0.4 // indirect
@@ -224,7 +229,7 @@ require (
 	github.com/mattn/go-isatty v0.0.16 // indirect
 	github.com/mattn/go-runewidth v0.0.13 // indirect
 	github.com/mattn/go-sqlite3 v2.0.3+incompatible // indirect
-	github.com/matttproud/golang_protobuf_extensions v1.0.1 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
 	github.com/maxymania/go-system v0.0.0-20170110133659-647cc364bf0b // indirect
 	github.com/mendsley/gojwk v0.0.0-20141217222730-4d5ec6e58103 // indirect
 	github.com/miekg/dns v1.1.50 // indirect
@@ -254,6 +259,7 @@ require (
 	github.com/prometheus/common v0.37.0 // indirect
 	github.com/prometheus/procfs v0.8.0 // indirect
 	github.com/prometheus/statsd_exporter v0.22.8 // indirect
+	github.com/rcrowley/go-metrics v0.0.0-20200313005456-10cdbea86bc0 // indirect
 	github.com/rivo/uniseg v0.4.2 // indirect
 	github.com/rs/cors v1.8.2 // indirect
 	github.com/rs/xid v1.4.0 // indirect
@@ -269,12 +275,16 @@ require (
 	github.com/spacewander/go-suffix-tree v0.0.0-20191010040751-0865e368c784 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/stretchr/objx v0.5.0 // indirect
+	github.com/tchap/go-patricia/v2 v2.3.1 // indirect
 	github.com/toorop/go-dkim v0.0.0-20201103131630-e1cd1a0a5208 // indirect
 	github.com/trustelem/zxcvbn v1.0.1 // indirect
 	github.com/wk8/go-ordered-map v1.0.0 // indirect
 	github.com/xanzy/ssh-agent v0.3.2 // indirect
+	github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb // indirect
+	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/xo/terminfo v0.0.0-20210125001918-ca9a967f8778 // indirect
 	github.com/xrash/smetrics v0.0.0-20201216005158-039620a65673 // indirect
+	github.com/yashtewari/glob-intersection v0.1.0 // indirect
 	go.etcd.io/etcd/api/v3 v3.5.6 // indirect
 	go.etcd.io/etcd/client/pkg/v3 v3.5.6 // indirect
 	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.36.4 // indirect
@@ -284,7 +294,7 @@ require (
 	golang.org/x/mod v0.9.0 // indirect
 	golang.org/x/sync v0.1.0 // indirect
 	golang.org/x/sys v0.6.0 // indirect
-	golang.org/x/time v0.1.0 // indirect
+	golang.org/x/time v0.3.0 // indirect
 	golang.org/x/tools v0.7.0 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect