Adding Extra specs JSON Schema validation

README.md

@@ -75,7 +75,8 @@ To this end, this provider supports the following extra specs schema:
         "enable_boot_debug": {
             "type": "boolean",
             "description": "Allows providers to set the -x flag in the runner install script."
-        }
+        },
+	    "additionalProperties": false
     }
 }
 ```

go.mod

@@ -10,6 +10,7 @@ require (
 	github.com/juju/retry v1.0.0
 	github.com/pkg/errors v0.9.1
 	github.com/stretchr/testify v1.8.4
+	github.com/xeipuuv/gojsonschema v1.2.0
 )
 
 require (
@@ -43,6 +44,8 @@ require (
 	github.com/rogpeppe/go-internal v1.12.0 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/teris-io/shortid v0.0.0-20220617161101-71ec9f2aa569 // indirect
+	github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f // indirect
+	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
 	github.com/zitadel/oidc/v2 v2.12.0 // indirect
 	golang.org/x/crypto v0.16.0 // indirect
 	golang.org/x/net v0.19.0 // indirect

go.sum

@@ -141,13 +141,20 @@ github.com/sirupsen/logrus v1.9.3 h1:dueUQJ1C2q9oE3F7wvmSGAaVtTmUizReu6fjN8uqzbQ
 github.com/sirupsen/logrus v1.9.3/go.mod h1:naHLuLoDiP4jHNo9R0sCBMtWGeIprob74mVsIT4qYEQ=
 github.com/stretchr/objx v0.1.0/go.mod h1:HFkY916IF+rwdDfMAkV7OtwuqBVzrE8GR6GFx+wExME=
 github.com/stretchr/objx v0.4.0/go.mod h1:YvHI0jy2hoMjB+UWwv71VJQ9isScKT/TqJzVSSt89Yw=
+github.com/stretchr/testify v1.3.0/go.mod h1:M5WIy9Dh21IEIfnGCwXGc5bZfKNJtfHm1UVUgZn+9EI=
 github.com/stretchr/testify v1.7.0/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.7.1/go.mod h1:6Fq8oRcR53rry900zMqJjRRixrwX3KX962/h/Wwjteg=
 github.com/stretchr/testify v1.8.0/go.mod h1:yNjHg4UonilssWZ8iaSj1OCr/vHnekPRkoO+kdMU+MU=
 github.com/stretchr/testify v1.8.4 h1:CcVxjf3Q8PM0mHUKJCdn+eZZtm5yQwehR5yeSVQQcUk=
 github.com/stretchr/testify v1.8.4/go.mod h1:sz/lmYIOXD/1dqDmKjjqLyZ2RngseejIcXlSw2iwfAo=
 github.com/teris-io/shortid v0.0.0-20220617161101-71ec9f2aa569 h1:xzABM9let0HLLqFypcxvLmlvEciCHL7+Lv+4vwZqecI=
 github.com/teris-io/shortid v0.0.0-20220617161101-71ec9f2aa569/go.mod h1:2Ly+NIftZN4de9zRmENdYbvPQeaVIYKWpLFStLFEBgI=
+github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f h1:J9EGpcZtP0E/raorCMxlFGSTBrsSlaDGf3jU/qvAE2c=
+github.com/xeipuuv/gojsonpointer v0.0.0-20180127040702-4e3ac2762d5f/go.mod h1:N2zxlSyiKSe5eX1tZViRH5QA0qijqEDrYZiPEAiq3wU=
+github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 h1:EzJWgHovont7NscjpAxXsDA8S8BMYve8Y5+7cuRE7R0=
+github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415/go.mod h1:GwrjFmJcFw6At/Gs6z4yjiIwzuJ1/+UwLxMQDVQXShQ=
+github.com/xeipuuv/gojsonschema v1.2.0 h1:LhYJRs+L4fBtjZUfuSZIKGeVu0QRy8e5Xi7D17UxZ74=
+github.com/xeipuuv/gojsonschema v1.2.0/go.mod h1:anYRn/JVcOK2ZgGU+IjEV4nwlhoK5sQluxsYJ78Id3Y=
 github.com/yuin/goldmark v1.1.27/go.mod h1:3hX8gzYuyVAZsxl0MRgGTJEmQBFcNTphYh9decYSb74=
 github.com/yuin/goldmark v1.4.13/go.mod h1:6yULJ656Px+3vBD8DxQVa3kxgyrAnzto9xy5taEt/CY=
 github.com/zitadel/oidc/v2 v2.12.0 h1:4aMTAy99/4pqNwrawEyJqhRb3yY3PtcDxnoDSryhpn4=

provider/specs.go

@@ -7,23 +7,68 @@ package provider
 
 import (
 	"encoding/json"
+	"fmt"
 
 	commonParams "github.com/cloudbase/garm-provider-common/params"
 	"github.com/pkg/errors"
+	"github.com/xeipuuv/gojsonschema"
 )
 
+const jsonSchema string = `
+	{
+		"$schema": "http://cloudbase.it/garm-provider-lxd/schemas/extra_specs#",
+		"type": "object",
+		"description": "Schema defining supported extra specs for the Garm LXD Provider",
+		"properties": {
+			"extra_packages": {
+				"type": "array",
+				"description": "A list of packages that cloud-init should install on the instance.",
+				"items": {
+					"type": "string"
+				}
+			},
+			"disable_updates": {
+				"type": "boolean",
+				"description": "Whether to disable updates when cloud-init comes online."
+			},
+			"enable_boot_debug": {
+				"type": "boolean",
+				"description": "Allows providers to set the -x flag in the runner install script."
+			},
+			"additionalProperties": false
+		}
+	}
+`
+
 type extraSpecs struct {
 	DisableUpdates  bool     `json:"disable_updates"`
 	ExtraPackages   []string `json:"extra_packages"`
 	EnableBootDebug bool     `json:"enable_boot_debug"`
 }
 
+func jsonSchemaValidation(schema json.RawMessage) error {
+	schemaLoader := gojsonschema.NewStringLoader(jsonSchema)
+	extraSpecsLoader := gojsonschema.NewBytesLoader(schema)
+	result, err := gojsonschema.Validate(schemaLoader, extraSpecsLoader)
+	if err != nil {
+		return fmt.Errorf("failed to validate schema: %w", err)
+	}
+	if !result.Valid() {
+		return fmt.Errorf("schema validation failed: %s", result.Errors())
+	}
+	return nil
+}
+
 func parseExtraSpecsFromBootstrapParams(bootstrapParams commonParams.BootstrapInstance) (extraSpecs, error) {
 	specs := extraSpecs{}
 	if bootstrapParams.ExtraSpecs == nil {
 		return specs, nil
 	}
 
+	if err := jsonSchemaValidation(bootstrapParams.ExtraSpecs); err != nil {
+		return specs, fmt.Errorf("failed to validate extra specs: %w", err)
+	}
+
 	if err := json.Unmarshal(bootstrapParams.ExtraSpecs, &specs); err != nil {
 		return specs, errors.Wrap(err, "unmarshaling extra specs")
 	}