Alternatives for serving plugin

backend/datasource/datasource.go

@@ -0,0 +1,85 @@
+package datasource
+
+import (
+	"context"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+)
+
+// CheckDataSourceHealthRequest contains the healthcheck request
+type CheckDataSourceHealthRequest struct {
+	pluginConfig     backend.PluginConfig
+	OrgID            int64
+	DataSourceConfig backend.DataSourceConfig
+}
+
+// CheckDataSourceHealthHandler enables users to send health check
+// requests to a data source plugin.
+type CheckDataSourceHealthHandler interface {
+	CheckDataSourceHealth(ctx context.Context, req *CheckDataSourceHealthRequest) (*backend.CheckHealthResult, error)
+}
+
+type CheckDataSourceHealthHandlerFunc func(ctx context.Context, req *CheckDataSourceHealthRequest) (*backend.CheckHealthResult, error)
+
+func (fn CheckDataSourceHealthHandlerFunc) CheckHealth(ctx context.Context, req *backend.CheckHealthRequest) (*backend.CheckHealthResult, error) {
+	return fn(ctx, &CheckDataSourceHealthRequest{
+		pluginConfig:     req.PluginConfig,
+		OrgID:            req.PluginConfig.OrgID,
+		DataSourceConfig: *(req.PluginConfig.DataSourceConfig),
+	})
+}
+
+type CallDataSourceResourceRequest struct {
+	pluginConfig     backend.PluginConfig
+	OrgID            int64
+	DataSourceConfig backend.DataSourceConfig
+	Path             string
+	Method           string
+	URL              string
+	Headers          map[string][]string
+	Body             []byte
+	User             *backend.User
+}
+
+// CallDataSourceResourceHandler handles resource calls.
+type CallDataSourceResourceHandler interface {
+	CallDataSourceResource(ctx context.Context, req *CallDataSourceResourceRequest, sender backend.CallResourceResponseSender) error
+}
+
+type CallDataSourceResourceHandlerFunc func(ctx context.Context, req *CallDataSourceResourceRequest, sender backend.CallResourceResponseSender) error
+
+func (fn CallDataSourceResourceHandlerFunc) CallResource(ctx context.Context, req *backend.CallResourceRequest, sender backend.CallResourceResponseSender) error {
+	return fn(ctx, &CallDataSourceResourceRequest{
+		pluginConfig:     req.PluginConfig,
+		OrgID:            req.PluginConfig.OrgID,
+		DataSourceConfig: *(req.PluginConfig.DataSourceConfig),
+		User:             req.User,
+		Path:             req.Path,
+		URL:              req.URL,
+		Method:           req.Method,
+		Headers:          req.Headers,
+		Body:             req.Body,
+	}, sender)
+}
+
+func NewCheckDataSourceHealthHandlerFunc(h backend.CheckHealthHandler) CheckDataSourceHealthHandlerFunc {
+	return func(ctx context.Context, req *CheckDataSourceHealthRequest) (*backend.CheckHealthResult, error) {
+		return h.CheckHealth(ctx, &backend.CheckHealthRequest{
+			PluginConfig: req.pluginConfig,
+		})
+	}
+}
+
+func NewCallDataSourceResourceHandlerFunc(h backend.CallResourceHandler) CallDataSourceResourceHandlerFunc {
+	return func(ctx context.Context, req *CallDataSourceResourceRequest, sender backend.CallResourceResponseSender) error {
+		return h.CallResource(ctx, &backend.CallResourceRequest{
+			PluginConfig: req.pluginConfig,
+			User:         req.User,
+			Path:         req.Path,
+			URL:          req.URL,
+			Method:       req.Method,
+			Headers:      req.Headers,
+			Body:         req.Body,
+		}, sender)
+	}
+}

backend/datasource/serve.go

@@ -0,0 +1,25 @@
+package datasource
+
+import (
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
+)
+
+type Plugin interface {
+	CheckDataSourceHealthHandler
+	CallDataSourceResourceHandler
+	backend.QueryDataHandler
+}
+
+type PluginFactoryFunc func(logger log.Logger, c backend.ConfigurePlugin) Plugin
+
+func Serve(fn PluginFactoryFunc) {
+	backend.Serve(func(logger log.Logger, c backend.ConfigurePlugin) backend.ServeOpts {
+		ds := fn(logger, c)
+		return backend.ServeOpts{
+			CheckHealthHandler:  CheckDataSourceHealthHandlerFunc(ds.CheckDataSourceHealth),
+			CallResourceHandler: CallDataSourceResourceHandlerFunc(ds.CallDataSourceResource),
+			QueryDataHandler:    ds,
+		}
+	})
+}

backend/diagnostics/doc.go

@@ -0,0 +1,2 @@
+// Package diagnostics provides support for handling health checks.
+package diagnostics

backend/diagnostics/health_ok_handler.go

@@ -0,0 +1,21 @@
+package diagnostics
+
+import (
+	"context"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+)
+
+type okHandler struct {
+}
+
+func (h *okHandler) CheckHealth(ctx context.Context, req *backend.CheckHealthRequest) (*backend.CheckHealthResult, error) {
+	return &backend.CheckHealthResult{
+		Status: backend.HealthStatusOk,
+	}, nil
+}
+
+// OKCheckHealthHandler check health handler that returns backend.HealthStatusOk status.
+func OKCheckHealthHandler() backend.CheckHealthHandler {
+	return &okHandler{}
+}

backend/grpcplugin/serve.go

@@ -18,7 +18,7 @@ type ServeOpts struct {
 }
 
 // Serve starts serving the plugin over gRPC.
-func Serve(opts ServeOpts) error {
+func Serve(opts ServeOpts) {
 	versionedPlugins := make(map[int]plugin.PluginSet)
 	pSet := make(plugin.PluginSet)
 
@@ -57,6 +57,4 @@ func Serve(opts ServeOpts) error {
 		VersionedPlugins: versionedPlugins,
 		GRPCServer:       opts.GRPCServer,
 	})
-
-	return nil
 }

backend/resource/doc.go

@@ -0,0 +1,2 @@
+// Package resource provides support for handling resource calls.
+package resource

backend/resource/not_found_handler.go

@@ -0,0 +1,22 @@
+package resource
+
+import (
+	"context"
+	"net/http"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+)
+
+type notFoundHandler struct {
+}
+
+func (h *notFoundHandler) CallResource(ctx context.Context, req *backend.CallResourceRequest, sender backend.CallResourceResponseSender) error {
+	return sender.Send(&backend.CallResourceResponse{
+		Status: http.StatusNotFound,
+	})
+}
+
+// NotFoundHandler call resource handler that returns HTTP 404 status code.
+func NotFoundHandler() backend.CallResourceHandler {
+	return &notFoundHandler{}
+}

backend/serve.go

@@ -2,6 +2,7 @@ package backend
 
 import (
 	"github.com/grafana/grafana-plugin-sdk-go/backend/grpcplugin"
+	"github.com/grafana/grafana-plugin-sdk-go/backend/log"
 	"github.com/prometheus/client_golang/prometheus"
 )
 
@@ -13,8 +14,20 @@ type ServeOpts struct {
 	TransformDataHandler TransformDataHandler
 }
 
+type ConfigurePlugin struct {
+	Metrics prometheus.Registerer
+}
+
+type ServePluginFunc func(logger log.Logger, c ConfigurePlugin) ServeOpts
+
 // Serve starts serving the plugin over gRPC.
-func Serve(opts ServeOpts) error {
+func Serve(fn ServePluginFunc) {
+	logger := log.New()
+	c := ConfigurePlugin{
+		Metrics: prometheus.DefaultRegisterer,
+	}
+	opts := fn(logger, c)
+
 	pluginOpts := grpcplugin.ServeOpts{
 		DiagnosticsServer: newDiagnosticsSDKAdapter(prometheus.DefaultGatherer, opts.CheckHealthHandler),
 	}
@@ -31,5 +44,99 @@ func Serve(opts ServeOpts) error {
 		pluginOpts.TransformServer = newTransformSDKAdapter(opts.TransformDataHandler)
 	}
 
-	return grpcplugin.Serve(pluginOpts)
+	grpcplugin.Serve(pluginOpts)
+}
+
+type Plugin interface {
+	CheckHealthHandler
+	CallResourceHandler
+}
+
+type DataSourcePlugin interface {
+	Plugin
+	QueryDataHandler
+}
+
+type TransformPlugin interface {
+	TransformDataHandler
+}
+
+type PluginFactoryFunc func(logger log.Logger, c ConfigurePlugin) Plugin
+type DataSourcePluginFactoryFunc func(logger log.Logger, c ConfigurePlugin) DataSourcePlugin
+type TransformPluginFactoryFunc func(logger log.Logger, c ConfigurePlugin) TransformPlugin
+
+//ServePluginOpts options for serving plugins.
+type ServePluginOpts struct {
+	PluginProvider           PluginFactoryFunc
+	DataSourcePluginProvider DataSourcePluginFactoryFunc
+	TransformPluginProvider  TransformPluginFactoryFunc
+}
+
+func ServePluginExample(opts ServePluginOpts) {
+	logger := log.New()
+	c := ConfigurePlugin{
+		Metrics: prometheus.DefaultRegisterer,
+	}
+
+	if opts.PluginProvider != nil {
+		p := opts.PluginProvider(logger, c)
+		grpcplugin.Serve(grpcplugin.ServeOpts{
+			DiagnosticsServer: newDiagnosticsSDKAdapter(prometheus.DefaultGatherer, p),
+			ResourceServer:    newResourceSDKAdapter(p),
+		})
+		return
+	}
+
+	if opts.DataSourcePluginProvider != nil {
+		p := opts.DataSourcePluginProvider(logger, c)
+		grpcplugin.Serve(grpcplugin.ServeOpts{
+			DiagnosticsServer: newDiagnosticsSDKAdapter(prometheus.DefaultGatherer, p),
+			ResourceServer:    newResourceSDKAdapter(p),
+			DataServer:        newDataSDKAdapter(p),
+		})
+		return
+	}
+
+	if opts.TransformPluginProvider != nil {
+		p := opts.TransformPluginProvider(logger, c)
+		grpcplugin.Serve(grpcplugin.ServeOpts{
+			TransformServer: newTransformSDKAdapter(p),
+		})
+		return
+	}
+
+	panic("invalid arguments for serve plugin")
+}
+
+// ServePlugin starts serving the plugin over gRPC.
+func ServePlugin(factory PluginFactoryFunc) {
+	if factory == nil {
+		panic("factory func cannot be nil")
+	}
+
+	ServePluginExample(ServePluginOpts{
+		PluginProvider: factory,
+	})
+}
+
+// ServeDataSourcePlugin starts serving the data source plugin over gRPC.
+func ServeDataSourcePlugin(factory DataSourcePluginFactoryFunc) {
+	if factory == nil {
+		panic("factory func cannot be nil")
+	}
+
+	ServePluginExample(ServePluginOpts{
+		DataSourcePluginProvider: factory,
+	})
+}
+
+// ServeTransformPlugin starts serving the plugin over gRPC.
+func ServeTransformPlugin(factory TransformPluginFactoryFunc) {
+	if factory == nil {
+		panic("factory func cannot be nil")
+	}
+
+	ServePluginExample(ServePluginOpts{
+		TransformPluginProvider: factory,
+	})
 }

go.sum

@@ -84,13 +84,16 @@ github.com/prometheus/client_golang v0.9.1/go.mod h1:7SWBe2y4D6OKWSNQJUaRYU/AaXP
 github.com/prometheus/client_golang v1.0.0/go.mod h1:db9x61etRT2tGnBNRi70OPL5FsnadC4Ky3P0J6CfImo=
 github.com/prometheus/client_golang v1.3.0 h1:miYCvYqFXtl/J9FIy8eNpBfYthAEFg+Ys0XyUVEcDsc=
 github.com/prometheus/client_golang v1.3.0/go.mod h1:hJaj2vgQTGQmVCsAACORcieXFeDPbaTKGT+JTgUa3og=
+github.com/prometheus/client_golang v1.5.0 h1:Ctq0iGpCmr3jeP77kbF2UxgvRwzWWz+4Bh9/vJTyg1A=
+github.com/prometheus/client_golang v1.5.1 h1:bdHYieyGlH+6OLEk2YQha8THib30KP0/yD0YH9m6xcA=
 github.com/prometheus/client_model v0.0.0-20180712105110-5c3871d89910/go.mod h1:MbSGuTsp3dbXC40dX6PRTWyKYBIrTGTE9sqQNg2J8bo=
 github.com/prometheus/client_model v0.0.0-20190129233127-fd36f4220a90/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/client_model v0.1.0 h1:ElTg5tNp4DqfV7UQjDqv2+RJlNzsDtvNAWccbItceIE=
 github.com/prometheus/client_model v0.1.0/go.mod h1:xMI15A0UPsDsEKsMN9yxemIoYk6Tm2C1GtYGdfGttqA=
 github.com/prometheus/common v0.4.1/go.mod h1:TNfzLD0ON7rHzMJeJkieUDPYmFC7Snx/y86RQel1bk4=
 github.com/prometheus/common v0.7.0 h1:L+1lyG48J1zAQXA3RBX/nG/B3gjlHq0zTt2tlbJLyCY=
 github.com/prometheus/common v0.7.0/go.mod h1:DjGbpBbp5NYNiECxcL/VnbXCCaQpKd3tt26CguLLsqA=
+github.com/prometheus/common v0.9.1 h1:KOMtN28tlbam3/7ZKEYKHhKoJZYYj3gMH4uc62x7X7U=
 github.com/prometheus/procfs v0.0.0-20181005140218-185b4288413d/go.mod h1:c3At6R/oaqEKCNdg8wHV1ftS6bRYblBhIjjI8uT2IGk=
 github.com/prometheus/procfs v0.0.2/go.mod h1:TjEm7ze935MbeOT/UhFTIMYKhuLP4wbCsTZCD3I8kEA=
 github.com/prometheus/procfs v0.0.8 h1:+fpWZdT24pJBiqJdAwYBjPSk+5YmQzYNPYzQsdzLkt8=