add test for env vars

services/horizon/internal/environment.go

@@ -0,0 +1,65 @@
+package horizon
+
+import (
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/stellar/go/support/errors"
+)
+
+type EnvironmentManager struct {
+	oldEnvironment, newEnvironment map[string]string
+}
+
+func NewEnvironmentManager() *EnvironmentManager {
+	env := &EnvironmentManager{}
+	env.oldEnvironment = make(map[string]string)
+	env.newEnvironment = make(map[string]string)
+	return env
+}
+
+func (envManager *EnvironmentManager) InitializeEnvironmentVariables(environmentVars map[string]string) error {
+	var env strings.Builder
+	for key, value := range environmentVars {
+		env.WriteString(fmt.Sprintf("%s=%s ", key, value))
+	}
+
+	// prepare env
+	for key, value := range environmentVars {
+		innerErr := envManager.Add(key, value)
+		if innerErr != nil {
+			return errors.Wrap(innerErr, fmt.Sprintf(
+				"failed to set envvar (%s=%s)", key, value))
+		}
+	}
+	return nil
+}
+
+// Add sets a new environment variable, saving the original value (if any).
+func (envManager *EnvironmentManager) Add(key, value string) error {
+	// If someone pushes an environmental variable more than once, we don't want
+	// to lose the *original* value, so we're being careful here.
+	if _, ok := envManager.newEnvironment[key]; !ok {
+		if oldValue, ok := os.LookupEnv(key); ok {
+			envManager.oldEnvironment[key] = oldValue
+		}
+	}
+
+	envManager.newEnvironment[key] = value
+	return os.Setenv(key, value)
+}
+
+// Restore restores the environment prior to any modifications.
+//
+// You should probably use this alongside `defer` to ensure the global
+// environment isn't modified for longer than you intend.
+func (envManager *EnvironmentManager) Restore() {
+	for key := range envManager.newEnvironment {
+		if oldValue, ok := envManager.oldEnvironment[key]; ok {
+			os.Setenv(key, oldValue)
+		} else {
+			os.Unsetenv(key)
+		}
+	}
+}

services/horizon/internal/flags_test.go

@@ -2,6 +2,8 @@ package horizon
 
 import (
 	"fmt"
+	"github.com/spf13/cobra"
+	"os"
 	"testing"
 
 	"github.com/stretchr/testify/assert"
@@ -131,3 +133,55 @@ func Test_createCaptiveCoreConfig(t *testing.T) {
 		})
 	}
 }
+
+func TestEnvironmentVariables(t *testing.T) {
+	environmentVars := map[string]string{
+		"INGEST":                        "false",
+		"HISTORY_ARCHIVE_URLS":          "http://localhost:1570",
+		"DATABASE_URL":                  "postgres://postgres@localhost/test_332cb65e6b00?sslmode=disable&timezone=UTC",
+		"STELLAR_CORE_URL":              "http://localhost:11626",
+		"NETWORK_PASSPHRASE":            "Standalone Network ; February 2017",
+		"APPLY_MIGRATIONS":              "true",
+		"ENABLE_CAPTIVE_CORE_INGESTION": "false",
+		"CHECKPOINT_FREQUENCY":          "8",
+		"MAX_DB_CONNECTIONS":            "50",
+		"ADMIN_PORT":                    "6060",
+		"PORT":                          "8001",
+		"CAPTIVE_CORE_BINARY_PATH":      os.Getenv("HORIZON_INTEGRATION_TESTS_CAPTIVE_CORE_BIN"),
+		"CAPTIVE_CORE_CONFIG_PATH":      "../docker/captive-core-classic-integration-tests.cfg",
+		"CAPTIVE_CORE_USE_DB":           "true",
+	}
+	envManager := NewEnvironmentManager()
+	if err := envManager.InitializeEnvironmentVariables(environmentVars); err != nil {
+		fmt.Println(err)
+	}
+	config, flags := Flags()
+	horizonCmd := &cobra.Command{
+		Use:           "horizon",
+		Short:         "Client-facing api server for the Stellar network",
+		SilenceErrors: true,
+		SilenceUsage:  true,
+		Long:          "Client-facing API server for the Stellar network.",
+	}
+	if err := flags.Init(horizonCmd); err != nil {
+		fmt.Println(err)
+	}
+	if err := ApplyFlags(config, flags, ApplyOptions{RequireCaptiveCoreConfig: true, AlwaysIngest: false}); err != nil {
+		fmt.Println(err)
+	}
+	assert.Equal(t, config.Ingest, false)
+	assert.Equal(t, config.HistoryArchiveURLs, []string{"http://localhost:1570"})
+	assert.Equal(t, config.DatabaseURL, "postgres://postgres@localhost/test_332cb65e6b00?sslmode=disable&timezone=UTC")
+	assert.Equal(t, config.StellarCoreURL, "http://localhost:11626")
+	assert.Equal(t, config.NetworkPassphrase, "Standalone Network ; February 2017")
+	assert.Equal(t, config.ApplyMigrations, true)
+	assert.Equal(t, config.EnableCaptiveCoreIngestion, false)
+	assert.Equal(t, config.CheckpointFrequency, uint32(8))
+	assert.Equal(t, config.MaxDBConnections, 50)
+	assert.Equal(t, config.AdminPort, uint(6060))
+	assert.Equal(t, config.Port, uint(8001))
+	assert.Equal(t, config.CaptiveCoreBinaryPath, os.Getenv("HORIZON_INTEGRATION_TESTS_CAPTIVE_CORE_BIN"))
+	assert.Equal(t, config.CaptiveCoreConfigPath, "../docker/captive-core-classic-integration-tests.cfg")
+	assert.Equal(t, config.CaptiveCoreConfigUseDB, true)
+	envManager.Restore()
+}

services/horizon/internal/integration/parameters_test.go

@@ -431,12 +431,6 @@ func TestDisableTxSub(t *testing.T) {
 		test.Shutdown()
 	})
 	t.Run("horizon starts successfully when DISABLE_TX_SUB=true and INGEST=true", func(t *testing.T) {
-		//localParams := integration.MergeMaps(networkParamArgs, map[string]string{
-		//	//horizon.NetworkFlagName:           "testnet",
-		//	horizon.IngestFlagName:            "true",
-		//	horizon.DisableTxSubFlagName:      "true",
-		//	horizon.StellarCoreBinaryPathName: "/usr/bin/stellar-core",
-		//})
 		testConfig := integration.GetTestConfig()
 		testConfig.HorizonIngestParameters = map[string]string{
 			"disable-tx-sub": "true",