From 760362bec006ea4e26ad8b6ca9cd34a3a8bd0987 Mon Sep 17 00:00:00 2001
From: Nathan <148575555+nathan-artie@users.noreply.github.com>
Date: Sun, 17 Mar 2024 19:20:59 -0700
Subject: [PATCH] [postgres] Emit `float32` values for `real` columns (#298)

---
 integration_tests/postgres/main.go     | 2 +-
 lib/debezium/converters/passthrough.go | 4 ++--
 lib/postgres/parse/parse.go            | 8 ++++++++
 3 files changed, 11 insertions(+), 3 deletions(-)

diff --git a/integration_tests/postgres/main.go b/integration_tests/postgres/main.go
index 91cd3d2c..5d6126ec 100644
--- a/integration_tests/postgres/main.go
+++ b/integration_tests/postgres/main.go
@@ -687,7 +687,7 @@ const expectedPayloadTemplate = `{
 				"x": 12.34,
 				"y": 56.78
 			},
-			"c_real": 45.678001403808594,
+			"c_real": 45.678,
 			"c_serial": 1000000123,
 			"c_smallint": 32767,
 			"c_text": "QWERTYUIOP",
diff --git a/lib/debezium/converters/passthrough.go b/lib/debezium/converters/passthrough.go
index c1c3996c..3c4a4de8 100644
--- a/lib/debezium/converters/passthrough.go
+++ b/lib/debezium/converters/passthrough.go
@@ -78,10 +78,10 @@ func (FloatPassthrough) ToField(name string) debezium.Field {
 
 func (FloatPassthrough) Convert(value any) (any, error) {
 	switch castValue := value.(type) {
-	case float32, float64:
+	case float32:
 		return castValue, nil
 	}
-	return nil, fmt.Errorf("expected float32/float64 got %T with value: %v", value, value)
+	return nil, fmt.Errorf("expected float32 got %T with value: %v", value, value)
 }
 
 // float32, float64 -> float64
diff --git a/lib/postgres/parse/parse.go b/lib/postgres/parse/parse.go
index 3cabf9f9..2e982b0b 100644
--- a/lib/postgres/parse/parse.go
+++ b/lib/postgres/parse/parse.go
@@ -23,6 +23,14 @@ func ParseValue(colKind schema.DataType, value any) (any, error) {
 			return valString, nil
 		}
 		return nil, fmt.Errorf("value: %v not of string type for bit", value)
+	case schema.Real:
+		float64Value, ok := value.(float64)
+		if !ok {
+			return nil, fmt.Errorf("expected float64 got %T with value: %v", value, value)
+		}
+		// pgx returns `real`s as float64 even though they are always 32 bits
+		// https://www.postgresql.org/docs/current/datatype-numeric.html#DATATYPE-NUMERIC
+		return float32(float64Value), nil
 	case schema.UserDefinedText:
 		stringSlice, isOk := value.(string)
 		if !isOk {