RPC Plugin System

cmd/plugin.go

@@ -0,0 +1,18 @@
+package cmd
+
+import (
+	"github.com/salsadigitalauorg/shipshape/pkg/plugin"
+	"github.com/spf13/cobra"
+)
+
+var pluginCmd = &cobra.Command{
+	Use:   "plugin",
+	Short: "Manage shipshape plugins",
+	Run: func(cmd *cobra.Command, args []string) {
+		plugin.Run()
+	},
+}
+
+func init() {
+	rootCmd.AddCommand(pluginCmd)
+}

examples/plugin/sample.go

@@ -0,0 +1,47 @@
+package main
+
+import (
+	"bytes"
+	"fmt"
+	"os"
+
+	"github.com/hashicorp/go-hclog"
+	"github.com/hashicorp/go-plugin"
+	"github.com/salsadigitalauorg/shipshape/pkg/output"
+	shipshape_plugin "github.com/salsadigitalauorg/shipshape/pkg/plugin"
+	"github.com/salsadigitalauorg/shipshape/pkg/result"
+)
+
+type SampleOutput struct {
+	logger hclog.Logger
+}
+
+func (o *SampleOutput) Output(rl *result.ResultList) ([]byte, error) {
+	o.logger.Debug("message from SampleOutput.Output")
+	b := bytes.Buffer{}
+	fmt.Fprintln(&b, "ResultList:", *rl)
+	return b.Bytes(), nil
+}
+
+func main() {
+	logger := hclog.New(&hclog.LoggerOptions{
+		Level:      hclog.Trace,
+		Output:     os.Stderr,
+		JSONFormat: true,
+	})
+
+	outputter := &SampleOutput{
+		logger: logger,
+	}
+	// pluginMap is the map of plugins we can dispense.
+	var pluginMap = map[string]plugin.Plugin{
+		"outputter": &output.OutputterPlugin{Impl: outputter},
+	}
+
+	logger.Debug("message from plugin", "foo", "bar")
+
+	plugin.Serve(&plugin.ServeConfig{
+		HandshakeConfig: shipshape_plugin.Handshake,
+		Plugins:         pluginMap,
+	})
+}

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/go-sql-driver/mysql v1.6.0
 	github.com/goccy/go-json v0.10.2
 	github.com/gocolly/colly v1.2.0
+	github.com/hashicorp/go-plugin v1.6.1
 	github.com/hashicorp/go-version v1.6.0
 	github.com/hasura/go-graphql-client v0.9.2
 	github.com/jmespath/go-jmespath v0.4.0
@@ -22,7 +23,7 @@ require (
 	github.com/spf13/cobra v1.8.0
 	github.com/stretchr/testify v1.9.0
 	github.com/vmware-labs/yaml-jsonpath v0.3.2
-	golang.org/x/oauth2 v0.6.0
+	golang.org/x/oauth2 v0.11.0
 	gopkg.in/yaml.v3 v3.0.1
 )
 
@@ -36,18 +37,25 @@ require (
 	github.com/davecgh/go-spew v1.1.1 // indirect
 	github.com/dprotaso/go-yit v0.0.0-20191028211022-135eb7262960 // indirect
 	github.com/dustin/go-humanize v1.0.1 // indirect
+	github.com/fatih/color v1.7.0 // indirect
 	github.com/go-playground/validator/v10 v10.4.1 // indirect
 	github.com/gobwas/glob v0.2.3 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
 	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
 	github.com/golang/protobuf v1.5.4 // indirect
 	github.com/google/uuid v1.6.0 // indirect
+	github.com/hashicorp/go-hclog v0.14.1 // indirect
+	github.com/hashicorp/yamux v0.1.1 // indirect
 	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
 	github.com/kennygrant/sanitize v1.2.4 // indirect
 	github.com/klauspost/compress v1.17.9 // indirect
+	github.com/mattn/go-colorable v0.1.4 // indirect
+	github.com/mattn/go-isatty v0.0.12 // indirect
+	github.com/mitchellh/go-testing-interface v0.0.0-20171004221916-a61a99592b77 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
+	github.com/oklog/run v1.0.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/saintfish/chardet v0.0.0-20120816061221-3af4cd4741ca // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
@@ -57,6 +65,8 @@ require (
 	golang.org/x/sys v0.22.0 // indirect
 	golang.org/x/text v0.15.0 // indirect
 	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20231016165738-49dd2c1f3d0b // indirect
+	google.golang.org/grpc v1.59.0 // indirect
 	google.golang.org/protobuf v1.33.0 // indirect
 	nhooyr.io/websocket v1.8.7 // indirect
 )

go.sum

@@ -12,6 +12,8 @@ github.com/antchfx/xmlquery v1.3.11 h1:8aRK7l3+dJjL8ZmwgVzG5AXysrP7Mss2424tfntKW
 github.com/antchfx/xmlquery v1.3.11/go.mod h1:ywPcYkN0GvURUxXpUujaMVvuLSOYQBzoSfHKfAYezCE=
 github.com/antchfx/xpath v1.2.1 h1:qhp4EW6aCOVr5XIkT+l6LJ9ck/JsUH/yyauNgTQkBF8=
 github.com/antchfx/xpath v1.2.1/go.mod h1:i54GszH55fYfBmoZXapTHN8T8tkcHfRgLyVwwqzXNcs=
+github.com/bufbuild/protocompile v0.4.0 h1:LbFKd2XowZvQ/kajzguUp2DC9UEIQhIq77fZZlaQsNA=
+github.com/bufbuild/protocompile v0.4.0/go.mod h1:3v93+mbWn/v3xzN+31nwkJfrEpAUwp+BagBSZWx+TP8=
 github.com/containerd/typeurl/v2 v2.1.1 h1:3Q4Pt7i8nYwy2KmQWIw2+1hTvwTE/6w9FqcttATPO/4=
 github.com/containerd/typeurl/v2 v2.1.1/go.mod h1:IDp2JFvbwZ31H8dQbEIY7sDl2L3o3HZj1hsSQlywkQ0=
 github.com/cpuguy83/go-md2man/v2 v2.0.3/go.mod h1:tgQtvFlXSQOSOSIRvRPT7W67SCa46tRHOmNcaadrF8o=
@@ -27,6 +29,8 @@ github.com/drone/envsubst v1.0.3 h1:PCIBwNDYjs50AsLZPYdfhSATKaRg/FJmDc2D6+C2x8g=
 github.com/drone/envsubst v1.0.3/go.mod h1:N2jZmlMufstn1KEqvbHjw40h1KyTmnVzHcSc9bFiJ2g=
 github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
 github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
+github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
+github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fsnotify/fsnotify v1.4.7/go.mod h1:jwhsz4b93w/PPRr/qN1Yymfu8t87LnFCMoQvtojpjFo=
 github.com/gin-contrib/sse v0.1.0 h1:Y/yl/+YNO8GZSjAhjMsSuLt29uWRFHdHYUb5lYOV9qE=
 github.com/gin-contrib/sse v0.1.0/go.mod h1:RHrZQHXnP2xjPF+u1gW/2HnVO7nvIa9PG3Gm+fLHvGI=
@@ -92,14 +96,22 @@ github.com/graph-gophers/graphql-go v1.5.0 h1:fDqblo50TEpD0LY7RXk/LFVYEVqo3+tXMN
 github.com/graph-gophers/graphql-go v1.5.0/go.mod h1:YtmJZDLbF1YYNrlNAuiO5zAStUWc3XZT07iGsVqe1Os=
 github.com/graph-gophers/graphql-transport-ws v0.0.2 h1:DbmSkbIGzj8SvHei6n8Mh9eLQin8PtA8xY9eCzjRpvo=
 github.com/graph-gophers/graphql-transport-ws v0.0.2/go.mod h1:5BVKvFzOd2BalVIBFfnfmHjpJi/MZ5rOj8G55mXvZ8g=
+github.com/hashicorp/go-hclog v0.14.1 h1:nQcJDQwIAGnmoUWp8ubocEX40cCml/17YkF6csQLReU=
+github.com/hashicorp/go-hclog v0.14.1/go.mod h1:whpDNt7SSdeAju8AWKIWsul05p54N/39EeqMAyrmvFQ=
+github.com/hashicorp/go-plugin v1.6.1 h1:P7MR2UP6gNKGPp+y7EZw2kOiq4IR9WiqLvp0XOsVdwI=
+github.com/hashicorp/go-plugin v1.6.1/go.mod h1:XPHFku2tFo3o3QKFgSYo+cghcUhw1NA1hZyMK0PWAw0=
 github.com/hashicorp/go-version v1.6.0 h1:feTTfFNnjP967rlCxM/I9g701jU+RN74YKx2mOkIeek=
 github.com/hashicorp/go-version v1.6.0/go.mod h1:fltr4n8CU8Ke44wwGCBoEymUuxUHl09ZGVZPK5anwXA=
+github.com/hashicorp/yamux v0.1.1 h1:yrQxtgseBDrq9Y652vSRDvsKCJKOUD+GzTS4Y0Y8pvE=
+github.com/hashicorp/yamux v0.1.1/go.mod h1:CtWFDAQgb7dxtzFs4tWbplKIe2jSi3+5vKbgIO0SLnQ=
 github.com/hasura/go-graphql-client v0.9.2 h1:4FyAeVOu+GcS1BaoELWNyxzaLY7s+g72LLH+qYItdEY=
 github.com/hasura/go-graphql-client v0.9.2/go.mod h1:AarJlxO1I59MPqU/TC7gQP0BMFgPEqUTt5LYPvykasw=
 github.com/hpcloud/tail v1.0.0 h1:nfCOvKYfkgYP8hkirhJocXT2+zOD8yUNjXaWfTlyFKI=
 github.com/hpcloud/tail v1.0.0/go.mod h1:ab1qPbhIpdTxEkNHXyeSf5vhxWSCs/tWer42PpOxQnU=
 github.com/inconshreveable/mousetrap v1.1.0 h1:wN+x4NVGpMsO7ErUn/mUI3vEoE6Jt13X2s0bqwp9tc8=
 github.com/inconshreveable/mousetrap v1.1.0/go.mod h1:vpF70FUmC8bwa3OWnCshd2FqLfsEA9PFc4w1p2J65bw=
+github.com/jhump/protoreflect v1.15.1 h1:HUMERORf3I3ZdX05WaQ6MIpd/NJ434hTp5YiKgfCL6c=
+github.com/jhump/protoreflect v1.15.1/go.mod h1:jD/2GMKKE6OqX8qTjhADU1e6DShO+gavG9e0Q693nKo=
 github.com/jmespath/go-jmespath v0.4.0 h1:BEgLn5cpjn8UN1mAw4NjwDrS35OdebyEtFe+9YPoQUg=
 github.com/jmespath/go-jmespath v0.4.0/go.mod h1:T8mJZnbsbmF+m6zOOFylbeCJqk5+pHWvzYPziyZiYoo=
 github.com/jmespath/go-jmespath/internal/testify v1.5.1 h1:shLQSRRSCCPj3f2gpwzGwWFoC7ycTf1rcQZHOlsJ6N8=
@@ -125,11 +137,17 @@ github.com/leodido/go-urn v1.2.0 h1:hpXL4XnriNwQ/ABnpepYM/1vCLWNDfUNts8dX3xTG6Y=
 github.com/leodido/go-urn v1.2.0/go.mod h1:+8+nEpDfqqsY+g338gtMEUOtuK+4dEMhiQEgxpxOKII=
 github.com/lib/pq v1.10.1 h1:6VXZrLU0jHBYyAqrSPa+MgPfnSvTPuMgK+k0o5kVFWo=
 github.com/lib/pq v1.10.1/go.mod h1:AlVN5x4E4T544tWzH6hKfbfQvm3HdbOxrmggDNAPY9o=
+github.com/mattn/go-colorable v0.1.4 h1:snbPLB8fVfU9iwbbo30TPtbLRzwWu6aJS6Xh4eaaviA=
+github.com/mattn/go-colorable v0.1.4/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
+github.com/mattn/go-isatty v0.0.8/go.mod h1:Iq45c/XA43vh69/j3iqttzPXn0bhXyGjM0Hdxcsrc5s=
+github.com/mattn/go-isatty v0.0.10/go.mod h1:qgIWMr58cqv1PHHyhnkY9lrL7etaEgOFcMEpPG5Rm84=
 github.com/mattn/go-isatty v0.0.12 h1:wuysRhFDzyxgEmMf5xjvJ2M9dZoWAXNNr5LSBS7uHXY=
 github.com/mattn/go-isatty v0.0.12/go.mod h1:cbi8OIDigv2wuxKPP5vlRcQ1OAZbq2CE4Kysco4FUpU=
 github.com/mattn/go-sqlite3 v1.14.7/go.mod h1:NyWgC/yNuGj7Q9rpYnZvas74GogHl5/Z4A/KQRfk6bU=
 github.com/minio/selfupdate v0.4.0 h1:A7t07pN4Ch1tBTIRStW0KhUVyykz+2muCqFsITQeEW8=
 github.com/minio/selfupdate v0.4.0/go.mod h1:mcDkzMgq8PRcpCRJo/NlPY7U45O5dfYl2Y0Rg7IustY=
+github.com/mitchellh/go-testing-interface v0.0.0-20171004221916-a61a99592b77 h1:7GoSOOW2jpsfkntVKaS2rAr1TJqfcxotyaUcuxoZSzg=
+github.com/mitchellh/go-testing-interface v0.0.0-20171004221916-a61a99592b77/go.mod h1:kRemZodwjscx+RGhAo8eIhFbs2+BFgRtFPeD/KE+zxI=
 github.com/moby/buildkit v0.15.1 h1:J6wrew7hphKqlq1wuu6yaUb/1Ra7gEzDAovylGztAKM=
 github.com/moby/buildkit v0.15.1/go.mod h1:Yis8ZMUJTHX9XhH9zVyK2igqSHV3sxi3UN0uztZocZk=
 github.com/modern-go/concurrent v0.0.0-20180228061459-e0a39a4cb421/go.mod h1:6dJC0mAP4ikYIbvyc7fijjWJddQyLn8Ig3JB5CqoB9Q=
@@ -140,6 +158,8 @@ github.com/modern-go/reflect2 v1.0.2 h1:xBagoLtFs94CBntxluKeaWgTMpvLxC4ur3nMaC9G
 github.com/modern-go/reflect2 v1.0.2/go.mod h1:yWuevngMOJpCy52FWWMvUC8ws7m/LJsjYzDa0/r8luk=
 github.com/nikolalohinski/gonja/v2 v2.1.5 h1:oD8R+GpKMw6Xex9hmWvCQiWlvHfnbmSmu3F5nZ5eRI4=
 github.com/nikolalohinski/gonja/v2 v2.1.5/go.mod h1:l9DuWJvT/BddBr2SsmEimESD6msSqRw7u5HzI2Um+sc=
+github.com/oklog/run v1.0.0 h1:Ru7dDtJNOyC66gQ5dQmaCa0qIsAUFY3sFpK1Xk8igrw=
+github.com/oklog/run v1.0.0/go.mod h1:dlhp/R75TPv97u0XWUtDeV/lRKWPKSdTuV0TZvrmrQA=
 github.com/onsi/ginkgo v1.6.0/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
 github.com/onsi/ginkgo v1.10.2 h1:uqH7bpe+ERSiDa34FDOF7RikN6RzXgduUF8yarlZp94=
 github.com/onsi/ginkgo v1.10.2/go.mod h1:lLunBs/Ym6LB5Z9jYTR76FiuTmxDTDusOGeTQH+WWjE=
@@ -167,6 +187,7 @@ github.com/spf13/pflag v1.0.5/go.mod h1:McXfInJRrz4CZXVZOBLb0bTZqETkiAhM9Iw0y3An
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.5.2 h1:xuMeJ0Sdp5ZMRXx/aWO6RZxdr3beISkG5/G/aIRr3pY=
 github.com/stretchr/objx v0.5.2/go.mod h1:FRsXN1f5AsAjCGJKqEizvkpNtU+EGNCLh3NxZ/8L+MA=
+github.com/stretchr/testify v1.2.2/go.mod h1:a8OnRcib4nhh0OaRAV+Yts87kKdq0PP7pXfy6kDkUVs=
 github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.4.0/go.mod h1:j7eGeouHqKxXV5pUuKE4zz7dFj8WfuZ+81PSLYec5m4=
 github.com/stretchr/testify v1.5.1/go.mod h1:5W2xD1RspED5o8YsWQXVCued0rvSQ+mT+I5cxcmMvtA=
@@ -209,15 +230,17 @@ golang.org/x/net v0.0.0-20210916014120-12bc252f5db8/go.mod h1:9nx3DQGgdP8bBQD5qx
 golang.org/x/net v0.0.0-20211112202133-69e39bad7dc2/go.mod h1:9nx3DQGgdP8bBQD5qxJ1jj9UTztislL4KSBs9R2vV5Y=
 golang.org/x/net v0.25.0 h1:d/OCCoBEUq33pjydKrGQhw7IlUPI2Oylr+8qLx49kac=
 golang.org/x/net v0.25.0/go.mod h1:JkAGAh7GEvH74S6FOH42FLoXpXbE/aqXSrIQjXgsiwM=
-golang.org/x/oauth2 v0.6.0 h1:Lh8GPgSKBfWSwFvtuWOfeI3aAAnbXTSutYxJiOJFgIw=
-golang.org/x/oauth2 v0.6.0/go.mod h1:ycmewcwgD4Rpr3eZJLSB4Kyyljb3qDh40vJ8STE5HKw=
+golang.org/x/oauth2 v0.11.0 h1:vPL4xzxBM4niKCW6g9whtaWVXTJf1U5e4aZxxFx/gbU=
+golang.org/x/oauth2 v0.11.0/go.mod h1:LdF7O/8bLR/qWK9DrpXmbHLTouvRHK0SgJl0GmDBchk=
 golang.org/x/sync v0.0.0-20180314180146-1d60e4601c6f/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190423024810-112230192c58/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20190911185100-cd5d95a43a6e/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sync v0.0.0-20201020160332-67f06af15bc9/go.mod h1:RxMgew5VJxzue5/jJTE5uejpjVlOe/izrB70Jof72aM=
 golang.org/x/sys v0.0.0-20180909124046-d0be0721c37e/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 v0.0.0-20190222072716-a9d3bda3a223/go.mod h1:STP8DvDyc/dI5b8T5hshtkjS+E42TnysNCUPdjciGhY=
 golang.org/x/sys v0.0.0-20190412213103-97732733099d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20191008105621-543471e840be/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200116001909-b77594299b42/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200930185726-fdedc70b468f/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
@@ -248,6 +271,10 @@ golang.org/x/xerrors v0.0.0-20191204190536-9bdfabe68543/go.mod h1:I/5z698sn9Ka8T
 golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8TeJc9MKroUUfqBBauWjQqLJ2OPfmY0=
 google.golang.org/appengine v1.6.7 h1:FZR1q0exgwxzPzp/aF+VccGrSfxfPpkBqjIIEq3ru6c=
 google.golang.org/appengine v1.6.7/go.mod h1:8WjMMxjGQR8xUklV/ARdw2HLXBOI7O7uCIDZVag1xfc=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20231016165738-49dd2c1f3d0b h1:ZlWIi1wSK56/8hn4QcBp/j9M7Gt3U/3hZw3mC7vDICo=
+google.golang.org/genproto/googleapis/rpc v0.0.0-20231016165738-49dd2c1f3d0b/go.mod h1:swOH3j0KzcDDgGUWr+SNpyTen5YrXjS3eyPzFYKc6lc=
+google.golang.org/grpc v1.59.0 h1:Z5Iec2pjwb+LEOqzpB2MR12/eKFhDPhuqW91O+4bwUk=
+google.golang.org/grpc v1.59.0/go.mod h1:aUPDwccQo6OTjy7Hct4AfBPD1GptF4fyUjIkQ9YtF98=
 google.golang.org/protobuf v1.26.0-rc.1/go.mod h1:jlhhOSvTdKEhbULTjvd4ARK9grFBp09yW+WbY/TyQbw=
 google.golang.org/protobuf v1.27.1/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQnmE0givc=
 google.golang.org/protobuf v1.33.0 h1:uNO2rsAINq/JlFpSdYEKIZ0uKD/R9cpdv0T+yoGwGmI=

pkg/output/rpc.go

@@ -0,0 +1,43 @@
+package output
+
+import (
+	"net/rpc"
+
+	"github.com/hashicorp/go-plugin"
+	"github.com/salsadigitalauorg/shipshape/pkg/result"
+)
+
+// OutputterRPC is the client side implementation of the interface which is used
+// by the host to send data to the plugin and receive the result.
+type OutputterRPC struct{ client *rpc.Client }
+
+func (or *OutputterRPC) Output(rl *result.ResultList) ([]byte, error) {
+	var resp []byte
+	err := or.client.Call("Plugin.Output", rl, &resp)
+	return resp, err
+}
+
+// OutputterRPCServer is the server representation of our interface which is
+// used by the plugin to receive data from the host and return the result.
+type OutputterRPCServer struct {
+	Impl Outputter
+}
+
+func (os *OutputterRPCServer) Output(rl *result.ResultList, resp *[]byte) error {
+	b, err := os.Impl.Output(rl)
+	*resp = b
+	return err
+}
+
+// OutputterPlugin is what exposes the Outputter interface as a plugin.
+type OutputterPlugin struct {
+	Impl Outputter
+}
+
+func (p *OutputterPlugin) Server(*plugin.MuxBroker) (interface{}, error) {
+	return &OutputterRPCServer{Impl: p.Impl}, nil
+}
+
+func (OutputterPlugin) Client(b *plugin.MuxBroker, c *rpc.Client) (interface{}, error) {
+	return &OutputterRPC{client: c}, nil
+}

pkg/plugin/plugin.go

@@ -0,0 +1,65 @@
+package plugin
+
+import (
+	"fmt"
+	"log"
+	"os"
+	"os/exec"
+
+	"github.com/hashicorp/go-hclog"
+	"github.com/hashicorp/go-plugin"
+	"github.com/salsadigitalauorg/shipshape/pkg/output"
+	"github.com/salsadigitalauorg/shipshape/pkg/result"
+)
+
+var Handshake = plugin.HandshakeConfig{
+	ProtocolVersion:  1,
+	MagicCookieKey:   "SHIPSHAPE_PLUGIN",
+	MagicCookieValue: "28d1923e-f22f-41b7-9699-cdbf4a8e2faa",
+}
+
+// pluginMap is the map of plugins we can dispense.
+var pluginMap = map[string]plugin.Plugin{
+	"outputter": &output.OutputterPlugin{},
+}
+
+func Run() {
+	// Create an hclog.Logger
+	logger := hclog.New(&hclog.LoggerOptions{
+		Name:   "plugin",
+		Output: os.Stdout,
+		Level:  hclog.Debug,
+	})
+
+	// We're a host! Start by launching the plugin process.
+	client := plugin.NewClient(&plugin.ClientConfig{
+		HandshakeConfig: Handshake,
+		Plugins:         pluginMap,
+		Cmd:             exec.Command("./build/plugin-sample"),
+		Logger:          logger,
+	})
+	defer client.Kill()
+
+	// Connect via RPC
+	rpcClient, err := client.Client()
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	// Request the plugin
+	raw, err := rpcClient.Dispense("outputter")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	outputter := raw.(output.Outputter)
+	b, err := outputter.Output(&result.ResultList{
+		Policies: map[string][]string{"policy1": {"rule1", "rule2"}},
+		Results:  []result.Result{{Name: "result1", Passes: []string{"rule1"}}},
+	})
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	fmt.Println("output from plugin:", string(b))
+}