feat: show pagination

internal/output/output.go

@@ -54,10 +54,16 @@ type PlaintextOutputFn func(resource) string
 // We're trading off type safety for easy of use instead of defining a type for each expected resource.
 type resource map[string]interface{}
 
+type link map[string]string
+
+type links map[string]link
+
 // resources is the subset of data we need to display a command's plain text response for a list
 // of resources.
 type resources struct {
-	Items []resource `json:"items"`
+	Items      []resource `json:"items"`
+	Links      links      `json:"_links"`
+	TotalCount int        `json:"totalCount"`
 }
 
 // CmdOutputSingular builds a command response based on the flag the user provided and the shape of

internal/output/resource_output.go

@@ -3,6 +3,9 @@ package output
 import (
 	"encoding/json"
 	"fmt"
+	"math"
+	"net/url"
+	"strconv"
 	"strings"
 
 	"github.com/pkg/errors"
@@ -45,35 +48,60 @@ func CmdOutput(action string, outputKind string, input []byte) (string, error) {
 		// no success message
 	}
 
-	if isMultipleResponse {
-		if len(maybeResources.Items) == 0 {
-			return "No items found", nil
-		}
+	if !isMultipleResponse {
+		return plaintextOutput(SingularPlaintextOutputFn(maybeResource), successMessage+" "), nil
+	}
 
-		// the response could have various properties we want to show
-		keyExists := func(key string) bool { _, ok := maybeResources.Items[0][key]; return ok }
-		outputFn := MultiplePlaintextOutputFn
-		switch {
-		case keyExists("email"):
-			outputFn = MultipleEmailPlaintextOutputFn
-		case keyExists("_id"):
-			outputFn = MultipleIDPlaintextOutputFn
-		}
+	if len(maybeResources.Items) == 0 {
+		return "No items found", nil
+	}
 
-		items := make([]string, 0, len(maybeResources.Items))
-		for _, i := range maybeResources.Items {
-			items = append(items, outputFn(i))
-		}
+	// the response could have various properties we want to show
+	keyExists := func(key string) bool { _, ok := maybeResources.Items[0][key]; return ok }
+	outputFn := MultiplePlaintextOutputFn
+	switch {
+	case keyExists("email"):
+		outputFn = MultipleEmailPlaintextOutputFn
+	case keyExists("_id"):
+		outputFn = MultipleIDPlaintextOutputFn
+	}
 
-		return plaintextOutput("\n"+strings.Join(items, "\n"), successMessage), nil
+	items := make([]string, 0, len(maybeResources.Items))
+	for _, i := range maybeResources.Items {
+		items = append(items, outputFn(i))
 	}
 
-	return plaintextOutput(SingularPlaintextOutputFn(maybeResource), successMessage), nil
+	var (
+		pagination string
+		limit      int
+		offset     int
+	)
+	self, ok := maybeResources.Links["self"]
+	if ok && maybeResources.TotalCount > 0 {
+		selfURL, _ := url.Parse(self["href"])
+		limit, _ = strconv.Atoi(selfURL.Query().Get("limit"))
+		offset, _ = strconv.Atoi(selfURL.Query().Get("offset"))
+		maxResults := int(math.Min(float64(offset+limit), float64(maybeResources.TotalCount)))
+		pagination = fmt.Sprintf(
+			"\nShowing results %d - %d of %d.",
+			offset+1,
+			maxResults,
+			maybeResources.TotalCount,
+		)
+		if offset+limit < maybeResources.TotalCount {
+			pagination += fmt.Sprintf(" Use --offset %d for additional results.", offset+limit)
+		}
+	}
+
+	if successMessage != "" {
+		successMessage += "\n"
+	}
+	return plaintextOutput(strings.Join(items, "\n"), successMessage) + pagination, nil
 }
 
 func plaintextOutput(out string, successMessage string) string {
 	if successMessage != "" {
-		return fmt.Sprintf("%s %s", successMessage, out)
+		return fmt.Sprintf("%s%s", successMessage, out)
 	}
 
 	return out

internal/output/resource_output_test.go

@@ -12,6 +12,91 @@ import (
 )
 
 func TestCmdOutput(t *testing.T) {
+	// with no additional pagination - does not show offset help
+	t.Run("with paginated multiple resources", func(t *testing.T) {
+		input := `{
+			"_links": {
+				"self": {
+					"href": "/my-resources?limit=5",
+					"type": "application/json"
+				}
+			},
+			"items": [
+				{
+					"key": "test-key",
+					"name": "test-name"
+				}
+			],
+			"totalCount": 100
+		}`
+
+		t.Run("shows pagination", func(t *testing.T) {
+			expected := "* test-name (test-key)"
+			expected += "\nShowing results 1 - 5 of 100. Use --offset 5 for additional results."
+
+			result, err := output.CmdOutput("list", "plaintext", []byte(input))
+
+			require.NoError(t, err)
+			assert.Equal(t, expected, result)
+		})
+	})
+
+	t.Run("with a paginated offset shows pagination", func(t *testing.T) {
+		input := `{
+			"_links": {
+				"self": {
+					"href": "/my-resources?limit=5&offset=5",
+					"type": "application/json"
+				}
+			},
+			"items": [
+				{
+					"key": "test-key",
+					"name": "test-name"
+				}
+			],
+			"totalCount": 100
+		}`
+
+		t.Run("shows pagination", func(t *testing.T) {
+			expected := "* test-name (test-key)"
+			expected += "\nShowing results 6 - 10 of 100. Use --offset 10 for additional results."
+
+			result, err := output.CmdOutput("list", "plaintext", []byte(input))
+
+			require.NoError(t, err)
+			assert.Equal(t, expected, result)
+		})
+	})
+
+	t.Run("with no additional pagination does not show offset help", func(t *testing.T) {
+		input := `{
+			"_links": {
+				"self": {
+					"href": "/my-resources?limit=5&offset=95",
+					"type": "application/json"
+				}
+			},
+			"items": [
+				{
+					"key": "test-key",
+					"name": "test-name"
+				}
+			],
+			"totalCount": 100
+		}`
+
+		t.Run("shows pagination", func(t *testing.T) {
+			expected := "* test-name (test-key)"
+			expected += "\nShowing results 96 - 100 of 100."
+
+			result, err := output.CmdOutput("list", "plaintext", []byte(input))
+
+			require.NoError(t, err)
+			assert.Equal(t, expected, result)
+		})
+	})
+
 	t.Run("with multiple resources with an ID and name", func(t *testing.T) {
 		input := `{
 			"items": [
@@ -23,8 +108,8 @@ func TestCmdOutput(t *testing.T) {
 		}`
 
 		t.Run("with plaintext output", func(t *testing.T) {
-			t.Run("returns a success message", func(t *testing.T) {
-				expected := "\n* test-name (test-id)"
+			t.Run("returns a list of resources", func(t *testing.T) {
+				expected := "* test-name (test-id)"
 
 				result, err := output.CmdOutput("list", "plaintext", []byte(input))
 
@@ -84,7 +169,7 @@ func TestCmdOutput(t *testing.T) {
 
 		t.Run("with plaintext output", func(t *testing.T) {
 			t.Run("returns a success message", func(t *testing.T) {
-				expected := "Successfully created \n* test-name (test-key)"
+				expected := "Successfully created\n* test-name (test-key)"
 
 				result, err := output.CmdOutput("create", "plaintext", []byte(input))
 
@@ -116,7 +201,7 @@ func TestCmdOutput(t *testing.T) {
 
 		t.Run("with plaintext output", func(t *testing.T) {
 			t.Run("returns a success message", func(t *testing.T) {
-				expected := "Successfully created \n* test-email (test-id)"
+				expected := "Successfully created\n* test-email (test-id)"
 
 				result, err := output.CmdOutput("create", "plaintext", []byte(input))