Refactor filtering implementation (#7)

Refactor filtering implementation to resolve #6.

We couldn't continue using `map`, as it does not allow filtering on
multiple values of the same field (i.e., use `OR`) as per
[documentation](https://backstage.io/docs/features/software-catalog/software-catalog-api/#filtering).

Author: tdabasinskas

README.md

@@ -15,21 +15,21 @@ the low-level details of making HTTP requests and parsing responses, allowing de
 With Go installed, run the following to add the package to your project, along with its dependencies:
 
 ```bash
-go get github.com/tdabasinskas/go-backstage@v1
+go get github.com/tdabasinskas/go-backstage/v2
 ```
 
 Alternatively, you can add import the package as following and run `go get` to install it:
 
 ```go
-import "github.com/tdabasinskas/go-backstage"
+import "github.com/tdabasinskas/go-backstage/v2"
 ```
 
 ## Usage
 
 Add the package to your project as following:
 
 ```go
-import "github.com/tdabasinskas/go-backstage"
+import "github.com/tdabasinskas/go-backstage/v2"
 ```
 
 Once imported, create a new Backstage API client to access different parts of Backstage API:
@@ -49,7 +49,7 @@ The client than can be used to access different parts of the API, e.g. get the l
 
 ```go
 entities, response, err := c.Catalog.Entities.s.List(context.Background(), &ListEntityOptions{
-        Filters: ListEntityFilter{},
+        Filters: []string{},
         Fields:  []string{},
         Order:   []ListEntityOrder{{ Direction: OrderDescending, Field: "metadata.name" },
     },

backstage/entity.go

@@ -1,13 +1,11 @@
 package backstage
 
 import (
-	"bytes"
 	"context"
 	"errors"
 	"fmt"
 	"net/http"
 	"net/url"
-	"sort"
 	"strings"
 )
 
@@ -110,9 +108,6 @@ type EntityRelationTarget struct {
 	Namespace string `json:"namespace"`
 }
 
-// ListEntityFilter defines a condition that can be used to filter entities.
-type ListEntityFilter map[string]string
-
 // ListEntityOrder defines a condition that can be used to order entities.
 type ListEntityOrder struct {
 	// Direction is the direction to order by.
@@ -125,7 +120,7 @@ type ListEntityOrder struct {
 // ListEntityOptions specifies the optional parameters to the catalogService.List method.
 type ListEntityOptions struct {
 	// Filters is a set of conditions that can be used to filter entities.
-	Filters ListEntityFilter
+	Filters []string
 
 	// Fields is a set of fields that can be used to limit the response.
 	Fields []string
@@ -174,8 +169,8 @@ func (s *entityService) List(ctx context.Context, options *ListEntityOptions) ([
 
 	values := u.Query()
 	if options != nil {
-		if options.Filters != nil && len(options.Filters) > 0 {
-			values.Add("filter", options.Filters.string())
+		for _, f := range options.Filters {
+			values.Add("filter", f)
 		}
 
 		if options.Fields != nil && len(options.Fields) > 0 {
@@ -240,26 +235,6 @@ func (s *typedEntityService[T]) get(ctx context.Context, t string, n string, ns
 	return entity, resp, err
 }
 
-// string returns a string representation of the ListEntityFilter.
-func (f *ListEntityFilter) string() string {
-	sortedKeys := make([]string, 0, len(*f))
-	for key := range *f {
-		sortedKeys = append(sortedKeys, key)
-	}
-	sort.Strings(sortedKeys)
-
-	var b bytes.Buffer
-	for _, k := range sortedKeys {
-		if (*f)[k] != "" {
-			b.WriteString(fmt.Sprintf("%s=%s,", k, (*f)[k]))
-		} else {
-			b.WriteString(fmt.Sprintf("%s,", k))
-		}
-	}
-
-	return strings.TrimSuffix(b.String(), ",")
-}
-
 // string returns a string representation of the ListEntityOrder.
 func (o *ListEntityOrder) string() (string, error) {
 	if o.Direction != OrderAscending && o.Direction != OrderDescending {

backstage/entity_test.go

@@ -96,9 +96,7 @@ func TestEntityServiceList_Filter(t *testing.T) {
 	s := newEntityService(newCatalogService(c))
 
 	actual, resp, err := s.List(context.Background(), &ListEntityOptions{
-		Filters: ListEntityFilter{
-			"kind": "User",
-		},
+		Filters: []string{"kind=User"},
 	})
 	assert.NoError(t, err, "Get should not return an error")
 	assert.NotEmpty(t, resp, "Response should not be empty")
@@ -129,7 +127,6 @@ func TestEntityServiceList_Fields(t *testing.T) {
 	s := newEntityService(newCatalogService(c))
 
 	actual, resp, err := s.List(context.Background(), &ListEntityOptions{
-		Filters: ListEntityFilter{},
 		Fields: []string{
 			"metadata.name",
 		},
@@ -163,7 +160,6 @@ func TestEntityServiceList_Order(t *testing.T) {
 	s := newEntityService(newCatalogService(c))
 
 	actual, resp, err := s.List(context.Background(), &ListEntityOptions{
-		Filters: ListEntityFilter{},
 		Order: []ListEntityOrder{
 			{
 				Direction: OrderDescending,
@@ -182,7 +178,6 @@ func TestEntityServiceList_InvalidOrder(t *testing.T) {
 	s := newEntityService(newCatalogService(c))
 
 	_, _, err := s.List(context.Background(), &ListEntityOptions{
-		Filters: ListEntityFilter{},
 		Order: []ListEntityOrder{
 			{
 				Direction: "InvalidOrder",
@@ -213,51 +208,6 @@ func TestEntityServiceDelete(t *testing.T) {
 	assert.EqualValues(t, http.StatusNoContent, resp.StatusCode, "Response status code should match the one from the server")
 }
 
-// TestListEntityFilterString tests if list entity filter string is correctly generated.
-func TestListEntityFilterString(t *testing.T) {
-	tests := []struct {
-		name     string
-		filter   ListEntityFilter
-		expected string
-	}{
-		{
-			name:     "empty filter",
-			filter:   ListEntityFilter{},
-			expected: "",
-		},
-		{
-			name: "filter with one key-value pair",
-			filter: ListEntityFilter{
-				"key1": "value1",
-			},
-			expected: "key1=value1",
-		},
-		{
-			name: "filter with one key and no value",
-			filter: ListEntityFilter{
-				"key1": "",
-			},
-			expected: "key1",
-		},
-		{
-			name: "filter with multiple key-value pairs",
-			filter: ListEntityFilter{
-				"key1": "value1",
-				"key2": "value2",
-				"key3": "",
-			},
-			expected: "key1=value1,key2=value2,key3",
-		},
-	}
-
-	for _, test := range tests {
-		t.Run(test.name, func(t *testing.T) {
-			actual := test.filter.string()
-			assert.Equal(t, test.expected, actual, "List entity filter string should match expected value")
-		})
-	}
-}
-
 // TestListEntityOrderString tests if list entity order string is correctly generated.
 func TestListEntityOrderString(t *testing.T) {
 	tests := []struct {

examples/entities/go.mod

@@ -2,6 +2,6 @@ module exampleentities
 
 go 1.20
 
-replace github.com/tdabasinskas/go-backstage => ../..
+replace github.com/tdabasinskas/go-backstage/v2 => ../..
 
-require github.com/tdabasinskas/go-backstage v0.0.0-20230117064629-2a4ac9398d92
+require github.com/tdabasinskas/go-backstage/v2 v2.0.0-preview.2

examples/entities/go.sum

@@ -2,10 +2,9 @@ package main
 
 import (
 	"context"
+	"github.com/tdabasinskas/go-backstage/v2/backstage"
 	"log"
 	"os"
-
-	"github.com/tdabasinskas/go-backstage/backstage"
 )
 
 func main() {
@@ -26,15 +25,26 @@ func main() {
 
 	log.Println("Getting component entities...")
 	if entities, _, err := c.Catalog.Entities.List(context.Background(), &backstage.ListEntityOptions{
-		Filters: backstage.ListEntityFilter{
-			"kind": "component",
-		},
+		Filters: []string{"kind=component"},
 	}); err != nil {
 		log.Fatal(err)
 	} else {
 		log.Printf("Component entities: %v", entities)
 	}
 
+	log.Println("Getting location, API and component entities...")
+	if entities, _, err := c.Catalog.Entities.List(context.Background(), &backstage.ListEntityOptions{
+		Filters: []string{
+			"kind=component",
+			"kind=location",
+			"kind=api",
+		},
+	}); err != nil {
+		log.Fatal(err)
+	} else {
+		log.Printf("Component, location and API entities: %v", entities)
+	}
+
 	log.Println("Getting specific component entity by UID...")
 	if entity, _, err := c.Catalog.Entities.Get(context.Background(), "06f15cc8-b6b4-4e44-a9bd-1579029f8fb7"); err != nil {
 		log.Fatal(err)

examples/entities/main.go

@@ -2,6 +2,6 @@ module examplelocations
 
 go 1.20
 
-replace github.com/tdabasinskas/go-backstage => ../..
+replace github.com/tdabasinskas/go-backstage/v2 => ../..
 
-require github.com/tdabasinskas/go-backstage v0.0.0-20230117064629-2a4ac9398d92
+require github.com/tdabasinskas/go-backstage/v2 v2.0.0-preview.2

examples/locations/go.mod

@@ -6,7 +6,7 @@ import (
 	"net/http"
 	"os"
 
-	"github.com/tdabasinskas/go-backstage/backstage"
+	"github.com/tdabasinskas/go-backstage/v2/backstage"
 )
 
 func main() {

examples/locations/main.go

@@ -1,4 +1,4 @@
-module github.com/tdabasinskas/go-backstage
+module github.com/tdabasinskas/go-backstage/v2
 
 go 1.20