Use correct long description from DSA long RDF

- use date and DSA number as version identifier
- add tests for Check and Get calls

internal/resource/dsa/dsa_test.go

@@ -0,0 +1,51 @@
+package dsa
+
+import (
+	"bytes"
+	"fmt"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+)
+
+func TestResource_Check(t *testing.T) {
+	input := strings.NewReader("{}")
+	output := &bytes.Buffer{}
+
+	resource := NewResource(input, output)
+
+	err := resource.Check()
+
+	assert.NoError(t, err)
+
+	result := output.String()
+
+	assert.NotEmpty(t, result)
+}
+
+func TestResource_Get(t *testing.T) {
+	rdf, err := getRdfData(false)
+
+	item := rdf.Items[0]
+
+	parts := strings.SplitN(item.Title, " ", 2)
+
+	require.NoError(t, err)
+
+	input := strings.NewReader(fmt.Sprintf(
+		`{"source":{},"params":{},"version":{"date":"%s","dsa":"%s"}}`, item.Date, parts[0],
+	))
+	output := &bytes.Buffer{}
+
+	resource := NewResource(input, output)
+
+	err = resource.Get("/tmp")
+
+	assert.NoError(t, err)
+
+	result := output.String()
+
+	assert.NotEmpty(t, result)
+}