Parse postgres version output

Author: marccampbell

pkg/collect/postgres.go

@@ -4,6 +4,7 @@ import (
 	"database/sql"
 	"encoding/json"
 	"fmt"
+	"regexp"
 
 	_ "github.com/lib/pq"
 	"github.com/pkg/errors"
@@ -24,7 +25,14 @@ func Postgres(ctx *Context, databaseCollector *troubleshootv1beta1.Database) (ma
 			databaseConnection.Error = err.Error()
 		} else {
 			databaseConnection.IsConnected = true
-			databaseConnection.Version = version
+
+			postgresVersion, err := parsePostgresVersion(version)
+			if err != nil {
+				databaseConnection.Version = "Unknown"
+				databaseConnection.Error = err.Error()
+			} else {
+				databaseConnection.Version = postgresVersion
+			}
 		}
 	}
 
@@ -44,3 +52,14 @@ func Postgres(ctx *Context, databaseCollector *troubleshootv1beta1.Database) (ma
 
 	return postgresOutput, nil
 }
+
+func parsePostgresVersion(postgresVersion string) (string, error) {
+	re := regexp.MustCompile("PostgreSQL ([0-9.]*)")
+	matches := re.FindStringSubmatch(postgresVersion)
+	if len(matches) < 2 {
+		return "", errors.Errorf("postgres version did not match regex: %q", postgresVersion)
+	}
+
+	return matches[1], nil
+
+}

pkg/collect/postgres_test.go

@@ -0,0 +1,50 @@
+package collect
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"go.undefinedlabs.com/scopeagent"
+)
+
+func Test_parsePostgresVersion(t *testing.T) {
+	tests := []struct {
+		postgresVersion string
+		expect          string
+	}{
+		{
+			//  docker run -d --name pgnine -e POSTGRES_PASSWORD=password postgres:9
+			postgresVersion: "PostgreSQL 9.6.17 on x86_64-pc-linux-gnu (Debian 9.6.17-2.pgdg90+1), compiled by gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516, 64-bit",
+			expect:          "9.6.17",
+		},
+		{
+			//  docker run -d --name pgten -e POSTGRES_PASSWORD=password postgres:10
+			postgresVersion: "PostgreSQL 10.12 (Debian 10.12-2.pgdg90+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516, 64-bit",
+			expect:          "10.12",
+		},
+		{
+			//  docker run -d --name pgeleven -e POSTGRES_PASSWORD=password postgres:11
+			postgresVersion: "PostgreSQL 11.7 (Debian 11.7-2.pgdg90+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 6.3.0-18+deb9u1) 6.3.0 20170516, 64-bit",
+			expect:          "11.7",
+		},
+		{
+			// docker run -d --name pgtwelve -e POSTGRES_PASSWORD=password postgres:12
+			postgresVersion: "PostgreSQL 12.2 (Debian 12.2-2.pgdg100+1) on x86_64-pc-linux-gnu, compiled by gcc (Debian 8.3.0-6) 8.3.0, 64-bit",
+			expect:          "12.2",
+		},
+	}
+	for _, test := range tests {
+		t.Run(test.postgresVersion, func(t *testing.T) {
+			scopetest := scopeagent.StartTest(t)
+			defer scopetest.End()
+
+			req := require.New(t)
+			actual, err := parsePostgresVersion(test.postgresVersion)
+			req.NoError(err)
+
+			assert.Equal(t, test.expect, actual)
+
+		})
+	}
+}