add columns support to materialized view creation using Schema dump (#…

…379)

* update create view statement using schema dump in cql

* update CHANGELOG, adopt better golang strings usage

CHANGELOG.md

@@ -2,6 +2,8 @@
 
 ## v3.4.3 (unreleased)
  - Add optional 'columns' tag to Index definitions
+ - update dosa-idl into v3.2.1
+ - add columns support to materialized view creation using Schema dump
 
 ## v3.4.2 (2019-03-26)
  - Update version.VERSION

schema/cql/cql.go

@@ -22,6 +22,7 @@ package cql
 
 import (
 	"bytes"
+	"strings"
 	"text/template"
 
 	"github.com/uber-go/dosa"
@@ -55,15 +56,23 @@ func typeMap(t dosa.Type) string {
 	return "unknown"
 }
 
+func selectFieldsInCreatingView(columns []string) string {
+	if len(columns) == 0 {
+		return "*"
+	}
+	return `"` + strings.Join(columns, `", "`) + `"`
+}
+
 // precompile the template for create table
 var cqlCreateTableTemplate = template.Must(template.
 	New("cqlCreateTable").
 	Funcs(map[string]interface{}{"typeMap": typeMap}).
 	Funcs(map[string]interface{}{"uniqueKey": uniqueKey}).
+	Funcs(map[string]interface{}{"selectFieldsInCreatingView": selectFieldsInCreatingView}).
 	Parse(`create table "{{.Name}}" ({{range .Columns}}"{{- .Name -}}" {{ typeMap .Type -}}, {{end}}primary key {{ .Key }});
 {{- range $name, $indexdef := .Indexes }}
 create materialized view "{{- $name -}}" as
-  select * from "{{- $.Name -}}"
+  select {{selectFieldsInCreatingView $indexdef.Columns}} from "{{- $.Name -}}"
   where{{range $keynum, $key := $indexdef.Key.PartitionKeys }}{{if $keynum}} AND {{end}} "{{ $key }}" is not null {{- end}}
   primary key {{ uniqueKey $ $indexdef.Key }};
 {{- end -}}`))

schema/cql/cql_test.go

@@ -82,6 +82,30 @@ create materialized view "i2" as
 	}
 }
 
+func TestSelectFieldsInCreatingView(t *testing.T) {
+	data := []struct {
+		Columns   []string
+		Statement string
+	}{
+		{
+			Columns:   []string{"foo", "bar", "hello"},
+			Statement: `"foo", "bar", "hello"`,
+		},
+		{
+			Columns:   []string{"foo"},
+			Statement: `"foo"`,
+		},
+		{
+			Columns:   []string{},
+			Statement: "*",
+		},
+	}
+	for _, d := range data {
+		statement := selectFieldsInCreatingView(d.Columns)
+		assert.Equal(t, d.Statement, statement)
+	}
+}
+
 func BenchmarkCQL(b *testing.B) {
 	table, _ := dosa.TableFromInstance(&AllTypes{})
 	for i := 0; i < b.N; i++ {