reading plugin settings from environment variable

backend/common.go

@@ -7,7 +7,6 @@ import (
 
 	"github.com/grafana/grafana-plugin-sdk-go/backend/httpclient"
 	"github.com/grafana/grafana-plugin-sdk-go/backend/proxy"
-	"github.com/grafana/grafana-plugin-sdk-go/backend/useragent"
 	"github.com/grafana/grafana-plugin-sdk-go/internal/tenant"
 )
 
@@ -161,52 +160,6 @@ func (s *DataSourceInstanceSettings) GVK() GroupVersionKind {
 	}
 }
 
-// PluginContext holds contextual information about a plugin request, such as
-// Grafana organization, user and plugin instance settings.
-type PluginContext struct {
-	// OrgID is The Grafana organization identifier the request originating from.
-	OrgID int64
-
-	// PluginID is the unique identifier of the plugin that the request is for.
-	PluginID string
-
-	// PluginVersion is the version of the plugin that the request is for.
-	PluginVersion string
-
-	// User is the Grafana user making the request.
-	//
-	// Will not be provided if Grafana backend initiated the request,
-	// for example when request is coming from Grafana Alerting.
-	User *User
-
-	// AppInstanceSettings is the configured app instance settings.
-	//
-	// In Grafana an app instance is an app plugin of certain
-	// type that have been configured and enabled in a Grafana organization.
-	//
-	// Will only be set if request targeting an app instance.
-	AppInstanceSettings *AppInstanceSettings
-
-	// DataSourceConfig is the configured data source instance
-	// settings.
-	//
-	// In Grafana a data source instance is a data source plugin of certain
-	// type that have been configured and created in a Grafana organization.
-	//
-	// Will only be set if request targeting a data source instance.
-	DataSourceInstanceSettings *DataSourceInstanceSettings
-
-	// GrafanaConfig is the configuration settings provided by Grafana.
-	GrafanaConfig *GrafanaCfg
-
-	// UserAgent is the user agent of the Grafana server that initiated the gRPC request.
-	// Will only be set if request is made from Grafana v10.2.0 or later.
-	UserAgent *useragent.UserAgent
-
-	// The requested API version
-	APIVersion string
-}
-
 func setCustomOptionsFromHTTPSettings(opts *httpclient.Options, httpSettings *HTTPSettings) {
 	opts.CustomOptions = map[string]interface{}{}
 

backend/plugin_context.go

@@ -0,0 +1,112 @@
+package backend
+
+import (
+	"errors"
+	"fmt"
+	"os"
+	"strconv"
+	"strings"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend/useragent"
+)
+
+// PluginContext holds contextual information about a plugin request, such as
+// Grafana organization, user and plugin instance settings.
+type PluginContext struct {
+	// OrgID is The Grafana organization identifier the request originating from.
+	OrgID int64
+
+	// PluginID is the unique identifier of the plugin that the request is for.
+	PluginID string
+
+	// PluginVersion is the version of the plugin that the request is for.
+	PluginVersion string
+
+	// User is the Grafana user making the request.
+	//
+	// Will not be provided if Grafana backend initiated the request,
+	// for example when request is coming from Grafana Alerting.
+	User *User
+
+	// AppInstanceSettings is the configured app instance settings.
+	//
+	// In Grafana an app instance is an app plugin of certain
+	// type that have been configured and enabled in a Grafana organization.
+	//
+	// Will only be set if request targeting an app instance.
+	AppInstanceSettings *AppInstanceSettings
+
+	// DataSourceConfig is the configured data source instance
+	// settings.
+	//
+	// In Grafana a data source instance is a data source plugin of certain
+	// type that have been configured and created in a Grafana organization.
+	//
+	// Will only be set if request targeting a data source instance.
+	DataSourceInstanceSettings *DataSourceInstanceSettings
+
+	// GrafanaConfig is the configuration settings provided by Grafana.
+	GrafanaConfig *GrafanaCfg
+
+	// UserAgent is the user agent of the Grafana server that initiated the gRPC request.
+	// Will only be set if request is made from Grafana v10.2.0 or later.
+	UserAgent *useragent.UserAgent
+
+	// The requested API version
+	APIVersion string
+}
+
+// GetSettingFromEnv retrieves the environment variable value based on the provided key.
+// It first checks for a general plugin setting, then a plugin-specific setting, and finally
+// a data source-specific setting.
+// The search is case-insensitive for the key but case-sensitive for the data source UID.
+// NOTE: This method can't be used in multi-tenant environment such as grafana cloud
+func (pCtx *PluginContext) GetSettingFromEnv(key string) (output string) {
+	key = strings.TrimSpace(strings.ToUpper(key))
+
+	if v := strings.TrimSpace(os.Getenv(fmt.Sprintf("GF_PLUGIN_%s", key))); v != "" {
+		output = v
+	}
+
+	if pCtx == nil {
+		return output
+	}
+
+	pluginID := strings.TrimSpace(strings.ToUpper(pCtx.PluginID))
+	if v := strings.TrimSpace(os.Getenv(fmt.Sprintf("GF_PLUGIN_%s_%s", pluginID, key))); v != "" && pluginID != "" {
+		output = v
+	}
+
+	if pCtx.DataSourceInstanceSettings == nil {
+		return output
+	}
+
+	dsUID := strings.TrimSpace(strings.ToUpper(pCtx.DataSourceInstanceSettings.UID))
+	if v := strings.TrimSpace(os.Getenv(fmt.Sprintf("GF_DS_%s_%s", dsUID, key))); v != "" && dsUID != "" {
+		output = v
+	}
+
+	caseSensitiveDsUID := strings.TrimSpace(pCtx.DataSourceInstanceSettings.UID)
+	if v := strings.TrimSpace(os.Getenv(fmt.Sprintf("GF_DS_%s_%s", caseSensitiveDsUID, key))); v != "" && caseSensitiveDsUID != "" {
+		output = v
+	}
+
+	return output
+}
+
+// GetSettingAsBoolFromEnv retrieves the environment variable value as boolean based on the provided key.
+// NOTE: This method can't be used in multi-tenant environment such as grafana cloud
+func (pCtx *PluginContext) GetSettingAsBoolFromEnv(key string, defaultValue bool) (output bool, err error) {
+	if pCtx == nil {
+		return defaultValue, errors.New("invalid plugin context")
+	}
+	strValue := pCtx.GetSettingFromEnv(key)
+	if strValue == "" {
+		return defaultValue, nil
+	}
+	value, err := strconv.ParseBool(strValue)
+	if err != nil {
+		return defaultValue, fmt.Errorf("environment variable '%s' is invalid bool value '%s'", key, strValue)
+	}
+	return value, nil
+}

backend/plugin_context_test.go

@@ -0,0 +1,74 @@
+package backend_test
+
+import (
+	"testing"
+
+	"github.com/grafana/grafana-plugin-sdk-go/backend"
+	"github.com/stretchr/testify/require"
+)
+
+func TestPluginContext_GetSettingsFromEnv(t *testing.T) {
+	t.Run("should return blank value if no env variables present", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		output := pCtx.GetSettingFromEnv("MY_KEY")
+		require.Empty(t, output)
+	})
+	t.Run("should respect GF_PLUGIN_KEY value", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		t.Setenv("GF_PLUGIN_MY_KEY", "foo")
+		output := pCtx.GetSettingFromEnv("MY_KEY")
+		require.Equal(t, "foo", output)
+	})
+	t.Run("should respect GF_PLUGIN_PLUGIN_ID_KEY value", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		t.Setenv("GF_PLUGIN_MY_KEY", "foo")
+		t.Setenv("GF_PLUGIN_MY-PLUGIN-ID_MY_KEY", "bar")
+		output := pCtx.GetSettingFromEnv("MY_KEY")
+		require.Equal(t, "bar", output)
+	})
+	t.Run("should respect GF_DS_DS_ID_KEY value", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		t.Setenv("GF_PLUGIN_MY_KEY", "foo")
+		t.Setenv("GF_PLUGIN_MY-PLUGIN-ID_MY_KEY", "bar")
+		t.Setenv("GF_DS_MYDSUID_MY_KEY", "baz")
+		output := pCtx.GetSettingFromEnv("MY_KEY")
+		require.Equal(t, "baz", output)
+	})
+	t.Run("should respect case sensitive ds uid", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		t.Setenv("GF_PLUGIN_MY_KEY", "foo")
+		t.Setenv("GF_PLUGIN_MY-PLUGIN-ID_MY_KEY", "bar")
+		t.Setenv("GF_DS_myDsUid_MY_KEY", "BaZ")
+		t.Setenv("GF_DS_MYDSUID_MY_KEY", "baz")
+		output := pCtx.GetSettingFromEnv("MY_KEY")
+		require.Equal(t, "BaZ", output)
+	})
+}
+
+func TestPluginContext_GetSettingsAsBoolFromEnv(t *testing.T) {
+	t.Run("should return default value when no env variables present", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		output, err := pCtx.GetSettingAsBoolFromEnv("MY_KEY", false)
+		require.Nil(t, err)
+		require.Equal(t, false, output)
+	})
+	t.Run("should return default value when no env variables present but default value", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		output, err := pCtx.GetSettingAsBoolFromEnv("MY_KEY", true)
+		require.Nil(t, err)
+		require.Equal(t, true, output)
+	})
+	t.Run("should fail with incorrect bool value", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		t.Setenv("GF_PLUGIN_MY_KEY", "foo")
+		_, err := pCtx.GetSettingAsBoolFromEnv("MY_KEY", false)
+		require.NotNil(t, err)
+	})
+	t.Run("should parse with correct bool value from environment", func(t *testing.T) {
+		pCtx := backend.PluginContext{PluginID: "my-plugin-id", DataSourceInstanceSettings: &backend.DataSourceInstanceSettings{UID: "myDsUid"}}
+		t.Setenv("GF_PLUGIN_MY_KEY", "True")
+		output, err := pCtx.GetSettingAsBoolFromEnv("MY_KEY", false)
+		require.Nil(t, err)
+		require.Equal(t, true, output)
+	})
+}