From ba076ed5cc8d158028b4ea3b3ec1e029b92e9126 Mon Sep 17 00:00:00 2001
From: Jo Asplin <jo.asplin@met.no>
Date: Mon, 18 Dec 2023 13:22:42 +0100
Subject: [PATCH] Used reflection to avoid explicit field references

---
 .../postgresql/getobservations.go             |  3 ++
 .../storagebackend/postgresql/postgresql.go   | 37 ++++---------------
 .../postgresql/putobservations.go             |  2 +-
 3 files changed, 12 insertions(+), 30 deletions(-)

diff --git a/datastore/storagebackend/postgresql/getobservations.go b/datastore/storagebackend/postgresql/getobservations.go
index 1fcde71..2357379 100644
--- a/datastore/storagebackend/postgresql/getobservations.go
+++ b/datastore/storagebackend/postgresql/getobservations.go
@@ -17,6 +17,7 @@ import (
 
 var (
 	tsStringMdataGoNames []string // Go names for time series metadata of type string
+	tsStringMdataPBNames []string // protobuf names for time series metadata of type string
 
 	obspb2go map[string]string // association between observation specific protobuf name and
 	// (generated by protoc) Go name.
@@ -33,10 +34,12 @@ var (
 
 func init() {
 	tsStringMdataGoNames = []string{}
+	tsStringMdataPBNames = []string{}
 	for _, field := range reflect.VisibleFields(reflect.TypeOf(datastore.TSMetadata{})) {
 		if field.IsExported() && (field.Type.Kind() == reflect.String) {
 			goName := field.Name
 			tsStringMdataGoNames = append(tsStringMdataGoNames, goName)
+			tsStringMdataPBNames = append(tsStringMdataPBNames, common.ToSnakeCase(goName))
 		}
 	}
 
diff --git a/datastore/storagebackend/postgresql/postgresql.go b/datastore/storagebackend/postgresql/postgresql.go
index 78f1049..271abc5 100644
--- a/datastore/storagebackend/postgresql/postgresql.go
+++ b/datastore/storagebackend/postgresql/postgresql.go
@@ -92,41 +92,20 @@ func NewPostgreSQL() (*PostgreSQL, error) {
 
 // getTSMdataCols returns time series metadata column names.
 func getTSMdataCols() []string {
-	// ### TODO: modify to use reflection instead of explicit field referrals
-	return []string{
-		// --- BEGIN non-string metadata ---------------------------
+
+	// initialize cols with non-string metadata
+	cols := []string{
 		"link_href",
 		"link_rel",
 		"link_type",
 		"link_hreflang",
 		"link_title",
-		// --- END non-string metadata ---------------------------
-
-		// --- BEGIN string metadata ---------------------------
-		"version",
-		"type",
-		"title",
-		"summary",
-		"keywords",
-		"keywords_vocabulary",
-		"license",
-		"conventions",
-		"naming_authority",
-		"creator_type",
-		"creator_name",
-		"creator_email",
-		"creator_url",
-		"institution",
-		"project",
-		"source",
-		"platform",
-		"platform_vocabulary",
-		"standard_name",
-		"unit",
-		"instrument",
-		"instrument_vocabulary",
-		// --- END string metadata ---------------------------
 	}
+
+	// complete cols with string metadata
+	cols = append(cols, tsStringMdataPBNames...)
+
+	return cols
 }
 
 // createPlaceholders returns the list of n placeholder strings for
diff --git a/datastore/storagebackend/postgresql/putobservations.go b/datastore/storagebackend/postgresql/putobservations.go
index 8225a11..2ff5d31 100644
--- a/datastore/storagebackend/postgresql/putobservations.go
+++ b/datastore/storagebackend/postgresql/putobservations.go
@@ -81,7 +81,7 @@ func getTSColVals(tsMdata *datastore.TSMetadata) ([]interface{}, error) {
 
 	// --- BEGIN string metadata ---------------------------
 
-	// ### TODO: modify to use reflection instead of explicit field referrals
+	// ### TODO: modify to use reflection instead of explicit field referencing
 
 	colVals = append(colVals, []interface{}{
 		tsMdata.GetVersion(),