test: add a ttools helper for easier local testing

Previously a local test required to setup the local development
environment and passing a bunch of environment variables prior to
running `go test ./...`. Now we allow for environment variables to be
passed, but also default back to variables we used across tests and
pipelines as default, making testing a little more comfy.

test: add additional tests

fix: use os.LookupEnv instead

docs: add comment

internal/ttools/getenv.go

@@ -0,0 +1,16 @@
+package ttools
+
+import (
+	"os"
+)
+
+// GetEnvDefault looks up an environment variable, and return a default value
+// when it is not present
+func GetEnvDefault(key, dvalue string) string {
+	v, ok := os.LookupEnv(key)
+	if !ok {
+		return dvalue
+	}
+
+	return v
+}

internal/ttools/getenv_test.go

@@ -0,0 +1,70 @@
+package ttools
+
+import (
+	"os"
+	"testing"
+)
+
+const (
+	ENV_TEST_VARIABLE       = "test"
+	ENV_TEST_EMPTY_VARIABLE = ""
+)
+
+func setEnv() {
+	os.Setenv("ENV_TEST_VARIABLE", ENV_TEST_VARIABLE)
+	os.Setenv("ENV_TEST_EMPTY_VARIABLE", ENV_TEST_EMPTY_VARIABLE)
+}
+
+func unsetEnv() {
+	os.Unsetenv("ENV_TEST_VARIABLE")
+	os.Unsetenv("ENV_TEST_EMPTY_VARIABLE")
+}
+
+func TestGetEnvDefault(t *testing.T) {
+	type tcase struct {
+		key      string
+		dvalue   string
+		expected string
+	}
+
+	setEnv()
+	defer unsetEnv()
+
+	fn := func(tc tcase) func(*testing.T) {
+		return func(t *testing.T) {
+
+			v := GetEnvDefault(tc.key, tc.dvalue)
+
+			if v != tc.expected {
+				t.Errorf("\n\nexpected: %s \ngot: %s \n\n", tc.expected, v)
+			}
+		}
+	}
+
+	tests := map[string]tcase{
+		"should use default value": {
+			key:      "ENV_THAT_DOESNT_EXIST",
+			dvalue:   "DEFAULT_VALUE",
+			expected: "DEFAULT_VALUE",
+		},
+		"should get variable from environment": {
+			key:      "ENV_TEST_VARIABLE",
+			dvalue:   "DEFAULT_VALUE",
+			expected: ENV_TEST_VARIABLE,
+		},
+		"should use default when key is empty string": {
+			key:      "",
+			dvalue:   "DEFAULT_VALUE",
+			expected: "DEFAULT_VALUE",
+		},
+		"should get variable from empty string environment": {
+			key:      "ENV_TEST_EMPTY_VARIABLE",
+			dvalue:   "DEFAULT_VALUE",
+			expected: ENV_TEST_EMPTY_VARIABLE,
+		},
+	}
+
+	for name, tc := range tests {
+		t.Run(name, fn(tc))
+	}
+}

provider/postgis/postgis_internal_test.go

@@ -3,7 +3,6 @@ package postgis
 import (
 	"context"
 	"fmt"
-	"os"
 	"reflect"
 	"strconv"
 	"strings"
@@ -20,28 +19,23 @@ const TESTENV = "RUN_POSTGIS_TESTS"
 
 var defaultEnvConfig map[string]interface{}
 
-func GetTestPort() int {
-	port, err := strconv.ParseInt(os.Getenv("PGPORT"), 10, 32)
+func getConfigFromEnv() map[string]interface{} {
+	port, err := strconv.Atoi(ttools.GetEnvDefault("PGPORT", "5432"))
 	if err != nil {
-		// Since this is happening at init time, have a sane default
-		fmt.Fprintf(os.Stderr, "err parsing PGPORT: '%v' using default port: 5433", err)
-		return 5433
+		// if port is anything but int, fallback to default
+		port = 5432
 	}
-	return int(port)
-}
 
-func getConfigFromEnv() map[string]interface{} {
-	port := GetTestPort()
 	return map[string]interface{}{
-		ConfigKeyHost:        os.Getenv("PGHOST"),
+		ConfigKeyHost:        ttools.GetEnvDefault("PGHOST", "localhost"),
 		ConfigKeyPort:        port,
-		ConfigKeyDB:          os.Getenv("PGDATABASE"),
-		ConfigKeyUser:        os.Getenv("PGUSER"),
-		ConfigKeyPassword:    os.Getenv("PGPASSWORD"),
-		ConfigKeySSLMode:     os.Getenv("PGSSLMODE"),
-		ConfigKeySSLKey:      os.Getenv("PGSSLKEY"),
-		ConfigKeySSLCert:     os.Getenv("PGSSLCERT"),
-		ConfigKeySSLRootCert: os.Getenv("PGSSLROOTCERT"),
+		ConfigKeyDB:          ttools.GetEnvDefault("PGDATABASE", "tegola"),
+		ConfigKeyUser:        ttools.GetEnvDefault("PGUSER", "postgres"),
+		ConfigKeyPassword:    ttools.GetEnvDefault("PGPASSWORD", "postgres"),
+		ConfigKeySSLMode:     ttools.GetEnvDefault("PGSSLMODE", "disable"),
+		ConfigKeySSLKey:      ttools.GetEnvDefault("PGSSLKEY", ""),
+		ConfigKeySSLCert:     ttools.GetEnvDefault("PGSSLCERT", ""),
+		ConfigKeySSLRootCert: ttools.GetEnvDefault("PGSSLROOTCERT", ""),
 	}
 }
 
@@ -125,7 +119,7 @@ func TestMVTProviders(t *testing.T) {
 		}
 	}
 	tests := map[string]tcase{
-		"1": tcase{
+		"1": {
 			TCConfig: TCConfig{
 				LayerConfig: []map[string]interface{}{
 					{
@@ -254,7 +248,7 @@ func TestLayerGeomType(t *testing.T) {
 		"role no access to table": {
 			TCConfig: TCConfig{
 				ConfigOverride: map[string]interface{}{
-					ConfigKeyUser: os.Getenv("PGUSER_NO_ACCESS"),
+					ConfigKeyUser: ttools.GetEnvDefault("PGUSER_NO_ACCESS", "tegola_no_access"),
 				},
 				LayerConfig: []map[string]interface{}{
 					{
@@ -271,11 +265,11 @@ func TestLayerGeomType(t *testing.T) {
 			TCConfig: TCConfig{
 				ConfigOverride: map[string]interface{}{
 					ConfigKeyURI: fmt.Sprintf("postgres://%v:%v@%v:%v/%v",
-						os.Getenv("PGUSER"),
-						os.Getenv("PGPASSWORD"),
-						os.Getenv("PGHOST"),
-						GetTestPort(),
-						os.Getenv("PGDATABASE"),
+						defaultEnvConfig["user"],
+						defaultEnvConfig["password"],
+						defaultEnvConfig["host"],
+						defaultEnvConfig["port"],
+						defaultEnvConfig["database"],
 					),
 					ConfigKeyHost: "",
 					ConfigKeyPort: "",

provider/postgis/util_internal_test.go

@@ -3,7 +3,7 @@ package postgis
 import (
 	"context"
 	"fmt"
-	"os"
+	"strconv"
 	"testing"
 
 	"github.com/jackc/pgx/v4/pgxpool"
@@ -124,11 +124,15 @@ func TestDecipherFields(t *testing.T) {
 		expectedTags     map[string]interface{}
 	}
 
-	host := os.Getenv("PGHOST")
-	port := os.Getenv("PGPORT")
-	db := os.Getenv("PGDATABASE")
-	user := os.Getenv("PGUSER")
-	password := os.Getenv("PGPASSWORD")
+	host := ttools.GetEnvDefault("PGHOST", "localhost")
+	port, err := strconv.Atoi(ttools.GetEnvDefault("PGPORT", "5432"))
+	// if port is anything but int, fallback to default
+	if err != nil {
+		port = 5432
+	}
+	db := ttools.GetEnvDefault("PGDATABASE", "tegola")
+	user := ttools.GetEnvDefault("PGUSER", "postgres")
+	password := ttools.GetEnvDefault("PGPASSWORD", "postgres")
 
 	cs := fmt.Sprintf("postgres://%v:%v@%v:%v/%v", user, password, host, port, db)
 	dbconfig, err := BuildDBConfig(cs)