From 8622b0e3370e0010a86f6114ece2d9285df01a26 Mon Sep 17 00:00:00 2001
From: Sven Rebhan <36194019+srebhan@users.noreply.github.com>
Date: Mon, 16 Oct 2023 23:54:54 +0200
Subject: [PATCH] feat(migrations): Add migration for outputs.riemann_legacy
 (#14121)

---
 migrations/all/outputs_riemann_legacy.go      |   5 +
 migrations/common/output_options.go           |  19 ++++
 migrations/outputs_riemann_legacy/README.md   |   0
 .../outputs_riemann_legacy/migration.go       | 106 ++++++++++++++++++
 .../outputs_riemann_legacy/migration_test.go  |  61 ++++++++++
 .../testcases/general_options/expected.conf   |   5 +
 .../testcases/general_options/telegraf.conf   |   9 ++
 .../testcases/simple/expected.conf            |   3 +
 .../testcases/simple/telegraf.conf            |   8 ++
 9 files changed, 216 insertions(+)
 create mode 100644 migrations/all/outputs_riemann_legacy.go
 create mode 100644 migrations/common/output_options.go
 create mode 100644 migrations/outputs_riemann_legacy/README.md
 create mode 100644 migrations/outputs_riemann_legacy/migration.go
 create mode 100644 migrations/outputs_riemann_legacy/migration_test.go
 create mode 100644 migrations/outputs_riemann_legacy/testcases/general_options/expected.conf
 create mode 100644 migrations/outputs_riemann_legacy/testcases/general_options/telegraf.conf
 create mode 100644 migrations/outputs_riemann_legacy/testcases/simple/expected.conf
 create mode 100644 migrations/outputs_riemann_legacy/testcases/simple/telegraf.conf

diff --git a/migrations/all/outputs_riemann_legacy.go b/migrations/all/outputs_riemann_legacy.go
new file mode 100644
index 000000000..bac00ae8e
--- /dev/null
+++ b/migrations/all/outputs_riemann_legacy.go
@@ -0,0 +1,5 @@
+//go:build !custom || (migrations && (outputs || outputs.riemann_legacy))
+
+package all
+
+import _ "github.com/influxdata/telegraf/migrations/outputs_riemann_legacy" // register migration
diff --git a/migrations/common/output_options.go b/migrations/common/output_options.go
new file mode 100644
index 000000000..fda61ff76
--- /dev/null
+++ b/migrations/common/output_options.go
@@ -0,0 +1,19 @@
+package common
+
+type OutputOptions struct {
+	// General options
+	Alias string `toml:"alias,omitempty"`
+
+	// Filter options
+	NamePass       []string            `toml:"namepass,omitempty"`
+	NameDrop       []string            `toml:"namedrop,omitempty"`
+	FieldPassOld   []string            `toml:"pass,omitempty"`
+	FieldPass      []string            `toml:"fieldpass,omitempty"`
+	FieldDropOld   []string            `toml:"drop,omitempty"`
+	FieldDrop      []string            `toml:"fielddrop,omitempty"`
+	TagPassFilters map[string][]string `toml:"tagpass,omitempty"`
+	TagDropFilters map[string][]string `toml:"tagdrop,omitempty"`
+	TagExclude     []string            `toml:"tagexclude,omitempty"`
+	TagInclude     []string            `toml:"taginclude,omitempty"`
+	MetricPass     string              `toml:"metricpass,omitempty"`
+}
diff --git a/migrations/outputs_riemann_legacy/README.md b/migrations/outputs_riemann_legacy/README.md
new file mode 100644
index 000000000..e69de29bb
diff --git a/migrations/outputs_riemann_legacy/migration.go b/migrations/outputs_riemann_legacy/migration.go
new file mode 100644
index 000000000..4b16af4ca
--- /dev/null
+++ b/migrations/outputs_riemann_legacy/migration.go
@@ -0,0 +1,106 @@
+package outputs_riemann_legacy
+
+import (
+	"github.com/influxdata/toml"
+	"github.com/influxdata/toml/ast"
+
+	"github.com/influxdata/telegraf/migrations"
+	"github.com/influxdata/telegraf/migrations/common"
+)
+
+// Define "old" data structure
+type riemannLegacy struct {
+	URL       string `toml:"url"`
+	Transport string `toml:"transport"`
+	Separator string `toml:"separator"`
+	common.OutputOptions
+}
+
+// Define "new" data structure(s)
+type riemann struct {
+	URL       string `toml:"url"`
+	Separator string `toml:"separator"`
+
+	// Common options for outputs
+	Alias          string              `toml:"alias,omitempty"`
+	NamePass       []string            `toml:"namepass,omitempty"`
+	NameDrop       []string            `toml:"namedrop,omitempty"`
+	FieldPass      []string            `toml:"fieldpass,omitempty"`
+	FieldDrop      []string            `toml:"fielddrop,omitempty"`
+	TagPassFilters map[string][]string `toml:"tagpass,omitempty"`
+	TagDropFilters map[string][]string `toml:"tagdrop,omitempty"`
+	TagExclude     []string            `toml:"tagexclude,omitempty"`
+	TagInclude     []string            `toml:"taginclude,omitempty"`
+	MetricPass     string              `toml:"metricpass,omitempty"`
+}
+
+// Migration function
+func migrate(tbl *ast.Table) ([]byte, string, error) {
+	// Decode the old data structure
+	var old riemannLegacy
+	if err := toml.UnmarshalTable(tbl, &old); err != nil {
+		return nil, "", err
+	}
+
+	// Create new plugin configurations
+	cfg := migrations.CreateTOMLStruct("outputs", "riemann")
+	plugin := riemann{
+		URL:       old.Transport + "://" + old.URL,
+		Separator: old.Separator,
+	}
+	plugin.fillCommon(old.OutputOptions)
+	cfg.Add("outputs", "riemann", plugin)
+
+	// Marshal the new configuration
+	buf, err := toml.Marshal(cfg)
+	if err != nil {
+		return nil, "", err
+	}
+	buf = append(buf, []byte("\n")...)
+
+	// Create the new content to output
+	return buf, "", nil
+}
+
+func (j *riemann) fillCommon(o common.OutputOptions) {
+	j.Alias = o.Alias
+
+	if len(o.NamePass) > 0 {
+		j.NamePass = append(j.NamePass, o.NamePass...)
+	}
+	if len(o.NameDrop) > 0 {
+		j.NameDrop = append(j.NameDrop, o.NameDrop...)
+	}
+	if len(o.FieldPass) > 0 || len(o.FieldDropOld) > 0 {
+		j.FieldPass = append(j.FieldPass, o.FieldPass...)
+		j.FieldPass = append(j.FieldPass, o.FieldPassOld...)
+	}
+	if len(o.FieldDrop) > 0 || len(o.FieldDropOld) > 0 {
+		j.FieldDrop = append(j.FieldDrop, o.FieldDrop...)
+		j.FieldDrop = append(j.FieldDrop, o.FieldDropOld...)
+	}
+	if len(o.TagPassFilters) > 0 {
+		j.TagPassFilters = make(map[string][]string, len(o.TagPassFilters))
+		for k, v := range o.TagPassFilters {
+			j.TagPassFilters[k] = v
+		}
+	}
+	if len(o.TagDropFilters) > 0 {
+		j.TagDropFilters = make(map[string][]string, len(o.TagDropFilters))
+		for k, v := range o.TagDropFilters {
+			j.TagDropFilters[k] = v
+		}
+	}
+	if len(o.TagExclude) > 0 {
+		j.TagExclude = append(j.TagExclude, o.TagExclude...)
+	}
+	if len(o.TagInclude) > 0 {
+		j.TagInclude = append(j.TagInclude, o.TagInclude...)
+	}
+	j.MetricPass = o.MetricPass
+}
+
+// Register the migration function for the plugin type
+func init() {
+	migrations.AddPluginMigration("outputs.riemann_legacy", migrate)
+}
diff --git a/migrations/outputs_riemann_legacy/migration_test.go b/migrations/outputs_riemann_legacy/migration_test.go
new file mode 100644
index 000000000..cf570e483
--- /dev/null
+++ b/migrations/outputs_riemann_legacy/migration_test.go
@@ -0,0 +1,61 @@
+package outputs_riemann_legacy_test
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+
+	"github.com/influxdata/telegraf/config"
+	_ "github.com/influxdata/telegraf/migrations/outputs_riemann_legacy" // register migration
+	_ "github.com/influxdata/telegraf/plugins/outputs/riemann"           // register plugin
+)
+
+func TestCases(t *testing.T) {
+	// Get all directories in testdata
+	folders, err := os.ReadDir("testcases")
+	require.NoError(t, err)
+
+	for _, f := range folders {
+		// Only handle folders
+		if !f.IsDir() {
+			continue
+		}
+
+		t.Run(f.Name(), func(t *testing.T) {
+			testcasePath := filepath.Join("testcases", f.Name())
+			inputFile := filepath.Join(testcasePath, "telegraf.conf")
+			expectedFile := filepath.Join(testcasePath, "expected.conf")
+
+			// Read the expected output
+			expected := config.NewConfig()
+			require.NoError(t, expected.LoadConfig(expectedFile))
+			require.NotEmpty(t, expected.Outputs)
+
+			// Read the input data
+			input, remote, err := config.LoadConfigFile(inputFile)
+			require.NoError(t, err)
+			require.False(t, remote)
+			require.NotEmpty(t, input)
+
+			// Migrate
+			output, n, err := config.ApplyMigrations(input)
+			require.NoError(t, err)
+			require.NotEmpty(t, output)
+			require.GreaterOrEqual(t, n, uint64(1))
+			actual := config.NewConfig()
+			require.NoError(t, actual.LoadConfigData(output))
+
+			// Test the output
+			require.Len(t, actual.Outputs, len(expected.Outputs))
+			actualIDs := make([]string, 0, len(expected.Outputs))
+			expectedIDs := make([]string, 0, len(expected.Outputs))
+			for i := range actual.Outputs {
+				actualIDs = append(actualIDs, actual.Outputs[i].ID())
+				expectedIDs = append(expectedIDs, expected.Outputs[i].ID())
+			}
+			require.ElementsMatch(t, expectedIDs, actualIDs)
+		})
+	}
+}
diff --git a/migrations/outputs_riemann_legacy/testcases/general_options/expected.conf b/migrations/outputs_riemann_legacy/testcases/general_options/expected.conf
new file mode 100644
index 000000000..1c8aa82ec
--- /dev/null
+++ b/migrations/outputs_riemann_legacy/testcases/general_options/expected.conf
@@ -0,0 +1,5 @@
+[[outputs.riemann]]
+url = "udp://localhost:5555"
+separator = "."
+namepass = ["foo"]
+fieldpass = ["motor_*"]
diff --git a/migrations/outputs_riemann_legacy/testcases/general_options/telegraf.conf b/migrations/outputs_riemann_legacy/testcases/general_options/telegraf.conf
new file mode 100644
index 000000000..d35d5841e
--- /dev/null
+++ b/migrations/outputs_riemann_legacy/testcases/general_options/telegraf.conf
@@ -0,0 +1,9 @@
+# Configuration for the Riemann server to send metrics to
+[[outputs.riemann_legacy]]
+  url = "localhost:5555"
+  transport = "udp"
+  separator = "."
+
+  ## Metric filtering
+  namepass = ["foo"]
+  fieldpass = ["motor_*"]
diff --git a/migrations/outputs_riemann_legacy/testcases/simple/expected.conf b/migrations/outputs_riemann_legacy/testcases/simple/expected.conf
new file mode 100644
index 000000000..c91b500db
--- /dev/null
+++ b/migrations/outputs_riemann_legacy/testcases/simple/expected.conf
@@ -0,0 +1,3 @@
+[[outputs.riemann]]
+url = "tcp://localhost:5555"
+separator = " "
diff --git a/migrations/outputs_riemann_legacy/testcases/simple/telegraf.conf b/migrations/outputs_riemann_legacy/testcases/simple/telegraf.conf
new file mode 100644
index 000000000..9ba4e0954
--- /dev/null
+++ b/migrations/outputs_riemann_legacy/testcases/simple/telegraf.conf
@@ -0,0 +1,8 @@
+# Configuration for the Riemann server to send metrics to
+[[outputs.riemann_legacy]]
+  ## URL of server
+  url = "localhost:5555"
+  ## transport protocol to use either tcp or udp
+  transport = "tcp"
+  ## separator to use between input name and field name in Riemann service name
+  separator = " "
\ No newline at end of file