Add Go modules.

go.mod

diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..67c6851
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,11 @@
+module github.com/casbin/casbin-authz-plugin
+
+go 1.12
+
+require (
+	github.com/Microsoft/go-winio v0.4.14 // indirect
+	github.com/casbin/casbin v1.9.1
+	github.com/docker/go-connections v0.4.0 // indirect
+	github.com/docker/go-plugins-helpers v0.0.0-20181025120712-1e6269c305b8
+	golang.org/x/net v0.0.0-20190916140828-c8589233b77d // indirect
+)

go.sum

diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..540c715
--- /dev/null
+++ b/go.sum
@@ -0,0 +1,25 @@
+github.com/Knetic/govaluate v3.0.1-0.20171022003610-9aa49832a739+incompatible h1:1G1pk05UrOh0NlF1oeaaix1x8XzrfjIDK47TY0Zehcw=
+github.com/Knetic/govaluate v3.0.1-0.20171022003610-9aa49832a739+incompatible/go.mod h1:r7JcOSlj0wfOMncg0iLm8Leh48TZaKVeNIfJntJ2wa0=
+github.com/Microsoft/go-winio v0.4.14 h1:+hMXMk01us9KgxGb7ftKQt2Xpf5hH/yky+TDA+qxleU=
+github.com/Microsoft/go-winio v0.4.14/go.mod h1:qXqCSQ3Xa7+6tgxaGTIe4Kpcdsi+P8jBhyzoq1bpyYA=
+github.com/casbin/casbin v1.9.1 h1:ucjbS5zTrmSLtH4XogqOG920Poe6QatdXtz1FEbApeM=
+github.com/casbin/casbin v1.9.1/go.mod h1:z8uPsfBJGUsnkagrt3G8QvjgTKFMBJ32UP8HpZllfog=
+github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
+github.com/docker/go-connections v0.4.0 h1:El9xVISelRB7BuFusrZozjnkIM5YnzCViNKohAFqRJQ=
+github.com/docker/go-connections v0.4.0/go.mod h1:Gbd7IOopHjR8Iph03tsViu4nIes5XhDvyHbTtUxmeec=
+github.com/docker/go-plugins-helpers v0.0.0-20181025120712-1e6269c305b8 h1:9Hsno4vmXpQ0yVAp07bLxS5dHH24w80xzmUCLil47ME=
+github.com/docker/go-plugins-helpers v0.0.0-20181025120712-1e6269c305b8/go.mod h1:LFyLie6XcDbyKGeVK6bHe+9aJTYCxWLBg5IrJZOaXKA=
+github.com/konsorten/go-windows-terminal-sequences v1.0.1/go.mod h1:T0+1ngSBFLxvqU3pZ+m/2kptfBszLMUkC4ZK/EgS/cQ=
+github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
+github.com/sirupsen/logrus v1.4.1/go.mod h1:ni0Sbl8bgC9z8RoU9G6nDWqqs/fq4eDPysMBDgk/93Q=
+github.com/stretchr/objx v0.1.1/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
+golang.org/x/crypto v0.0.0-20190308221718-c2843e01d9a2/go.mod h1:djNgcEr1/C05ACkg1iLfiJU5Ep61QUkGW8qpdssI0+w=
+golang.org/x/net v0.0.0-20190916140828-c8589233b77d h1:mCMDWKhNO37A7GAhOpHPbIw1cjd0V86kX1/WA9c7FZ8=
+golang.org/x/net v0.0.0-20190916140828-c8589233b77d/go.mod h1:z5CRVTTTmAJ677TzLLGU+0bjPO0LkuOLi4/5GtJWs/s=
+golang.org/x/sys v0.0.0-20180905080454-ebe1bf3edb33/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190215142949-d0b11bdaac8a/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
+golang.org/x/sys v0.0.0-20190507160741-ecd444e8653b h1:ag/x1USPSsqHud38I9BAC88qdNLDHHtQ4mlgQIZPPNA=
+golang.org/x/sys v0.0.0-20190507160741-ecd444e8653b/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/text v0.3.0/go.mod h1:NqM8EUOU14njkJ3fqMW+pc6Ldnwhi/IjpwHt7yyuwOQ=