Add support for Link header pagination

fastly/acl_entry.go

@@ -2,8 +2,12 @@ package fastly
 
 import (
 	"fmt"
+	"net/url"
 	"sort"
+	"strconv"
 	"time"
+
+	"github.com/peterhellberg/link"
 )
 
 type ACLEntry struct {
@@ -34,6 +38,10 @@ func (s entriesById) Less(i, j int) bool {
 type ListACLEntriesInput struct {
 	ServiceID string
 	ACLID     string
+	Direction string
+	PerPage   int
+	Page      int
+	Sort      string
 }
 
 // ListACLEntries return a list of entries for an ACL
@@ -63,6 +71,113 @@ func (c *Client) ListACLEntries(i *ListACLEntriesInput) ([]*ACLEntry, error) {
 	return es, nil
 }
 
+type ListAclEntriesPaginator struct {
+	consumed    bool
+	CurrentPage int
+	NextPage    int
+	LastPage    int
+	client      *Client
+	options     *ListACLEntriesInput
+}
+
+// HasNext returns a boolean indicating whether more pages are available
+func (p *ListAclEntriesPaginator) HasNext() bool {
+	return !p.consumed || p.Remaining() != 0
+}
+
+// Remaining returns the remaining page count
+func (p *ListAclEntriesPaginator) Remaining() int {
+	if p.LastPage == 0 {
+		return 0
+	}
+	return p.LastPage - p.CurrentPage
+}
+
+// GetNext retrieves data in the next page
+func (p *ListAclEntriesPaginator) GetNext() ([]*ACLEntry, error) {
+	return p.client.listACLEntriesWithPage(p.options, p)
+}
+
+// NewListACLEntriesPaginator returns a new ListAclEntriesPaginator
+func (c *Client) NewListACLEntriesPaginator(i *ListACLEntriesInput) *ListAclEntriesPaginator {
+	return &ListAclEntriesPaginator{
+		client:  c,
+		options: i,
+	}
+}
+
+// listACLEntriesWithPage return a list of entries for an ACL of a given page
+func (c *Client) listACLEntriesWithPage(i *ListACLEntriesInput, p *ListAclEntriesPaginator) ([]*ACLEntry, error) {
+
+	if i.ServiceID == "" {
+		return nil, ErrMissingServiceID
+	}
+
+	if i.ACLID == "" {
+		return nil, ErrMissingACLID
+	}
+
+	var perPage int
+	const maxPerPage = 100
+	if i.PerPage <= 0 {
+		perPage = maxPerPage
+	} else {
+		perPage = i.PerPage
+	}
+
+	if i.Page <= 0 && p.CurrentPage == 0 {
+		p.CurrentPage = 1
+	} else {
+		p.CurrentPage = p.CurrentPage + 1
+	}
+
+	path := fmt.Sprintf("/service/%s/acl/%s/entries", i.ServiceID, i.ACLID)
+	requestOptions := &RequestOptions{
+		Params: map[string]string{
+			"per_page": strconv.Itoa(perPage),
+			"page":     strconv.Itoa(p.CurrentPage),
+		},
+	}
+
+	if i.Direction != "" {
+		requestOptions.Params["direction"] = i.Direction
+	}
+	if i.Sort != "" {
+		requestOptions.Params["sort"] = i.Sort
+	}
+
+	resp, err := c.Get(path, requestOptions)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, l := range link.ParseResponse(resp) {
+		// indicates the Link response header contained the next page instruction
+		if l.Rel == "next" {
+			u, _ := url.Parse(l.URI)
+			query := u.Query()
+			p.NextPage, _ = strconv.Atoi(query["page"][0])
+		}
+		// indicates the Link response header contained the last page instruction
+		if l.Rel == "last" {
+			u, _ := url.Parse(l.URI)
+			query := u.Query()
+			p.LastPage, _ = strconv.Atoi(query["page"][0])
+		}
+	}
+
+	p.consumed = true
+
+	var es []*ACLEntry
+	if err := decodeBodyMap(resp.Body, &es); err != nil {
+		return nil, err
+	}
+
+	sort.Stable(entriesById(es))
+
+	return es, nil
+}
+
 // GetACLEntryInput is the input parameter to GetACLEntry function.
 type GetACLEntryInput struct {
 	ServiceID string

fastly/acl_entry_test.go

@@ -66,6 +66,28 @@ func TestClient_ACLEntries(t *testing.T) {
 		t.Errorf("Bad entries: %v", es)
 	}
 
+	// List with paginator
+	var es2 []*ACLEntry
+	var paginator *ListAclEntriesPaginator
+	record(t, fixtureBase+"list2", func(c *Client) {
+		paginator = c.NewListACLEntriesPaginator(&ListACLEntriesInput{
+			ServiceID: testService.ID,
+			ACLID:     testACL.ID,
+		})
+		es2, err = paginator.GetNext()
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(es2) != 1 {
+		t.Errorf("Bad entries: %v", es)
+	}
+
+	if paginator.HasNext() {
+		t.Errorf("Bad paginator (remaining: %v)", paginator.Remaining())
+	}
+
 	// Get
 	var ne *ACLEntry
 	record(t, fixtureBase+"get", func(c *Client) {

fastly/dictionary_item.go

@@ -4,7 +4,10 @@ import (
 	"fmt"
 	"net/url"
 	"sort"
+	"strconv"
 	"time"
+
+	"github.com/peterhellberg/link"
 )
 
 // DictionaryItem represents a dictionary item response from the Fastly API.
@@ -36,10 +39,13 @@ type ListDictionaryItemsInput struct {
 
 	// DictionaryID is the ID of the dictionary to retrieve items for (required).
 	DictionaryID string
+	Direction    string
+	PerPage      int
+	Page         int
+	Sort         string
 }
 
-// ListDictionaryItems returns the list of dictionary items for the
-// configuration version.
+// ListDictionaryItems returns a list of items for a dictionary
 func (c *Client) ListDictionaryItems(i *ListDictionaryItemsInput) ([]*DictionaryItem, error) {
 	if i.ServiceID == "" {
 		return nil, ErrMissingServiceID
@@ -63,6 +69,111 @@ func (c *Client) ListDictionaryItems(i *ListDictionaryItemsInput) ([]*Dictionary
 	return bs, nil
 }
 
+type ListDictionaryItemsPaginator struct {
+	consumed    bool
+	CurrentPage int
+	NextPage    int
+	LastPage    int
+	client      *Client
+	options     *ListDictionaryItemsInput
+}
+
+// HasNext returns a boolean indicating whether more pages are available
+func (p *ListDictionaryItemsPaginator) HasNext() bool {
+	return !p.consumed || p.Remaining() != 0
+}
+
+// Remaining returns the remaining page count
+func (p *ListDictionaryItemsPaginator) Remaining() int {
+	if p.LastPage == 0 {
+		return 0
+	}
+	return p.LastPage - p.CurrentPage
+}
+
+// GetNext retrieves data in the next page
+func (p *ListDictionaryItemsPaginator) GetNext() ([]*DictionaryItem, error) {
+	return p.client.listDictionaryItemsWithPage(p.options, p)
+}
+
+// NewListDictionaryItemsPaginator returns a new ListDictionaryItemsPaginator
+func (c *Client) NewListDictionaryItemsPaginator(i *ListDictionaryItemsInput) *ListDictionaryItemsPaginator {
+	return &ListDictionaryItemsPaginator{
+		client:  c,
+		options: i,
+	}
+}
+
+// listDictionaryItemsWithPage returns a list of items for a dictionary of a given page
+func (c *Client) listDictionaryItemsWithPage(i *ListDictionaryItemsInput, p *ListDictionaryItemsPaginator) ([]*DictionaryItem, error) {
+	if i.ServiceID == "" {
+		return nil, ErrMissingServiceID
+	}
+
+	if i.DictionaryID == "" {
+		return nil, ErrMissingDictionaryID
+	}
+
+	var perPage int
+	const maxPerPage = 100
+	if i.PerPage <= 0 {
+		perPage = maxPerPage
+	} else {
+		perPage = i.PerPage
+	}
+
+	if i.Page <= 0 && p.CurrentPage == 0 {
+		p.CurrentPage = 1
+	} else {
+		p.CurrentPage = p.CurrentPage + 1
+	}
+
+	path := fmt.Sprintf("/service/%s/dictionary/%s/items", i.ServiceID, i.DictionaryID)
+	requestOptions := &RequestOptions{
+		Params: map[string]string{
+			"per_page": strconv.Itoa(perPage),
+			"page":     strconv.Itoa(p.CurrentPage),
+		},
+	}
+
+	if i.Direction != "" {
+		requestOptions.Params["direction"] = i.Direction
+	}
+	if i.Sort != "" {
+		requestOptions.Params["sort"] = i.Sort
+	}
+
+	resp, err := c.Get(path, requestOptions)
+	if err != nil {
+		return nil, err
+	}
+
+	for _, l := range link.ParseResponse(resp) {
+		// indicates the Link response header contained the next page instruction
+		if l.Rel == "next" {
+			u, _ := url.Parse(l.URI)
+			query := u.Query()
+			p.NextPage, _ = strconv.Atoi(query["page"][0])
+		}
+		// indicates the Link response header contained the last page instruction
+		if l.Rel == "last" {
+			u, _ := url.Parse(l.URI)
+			query := u.Query()
+			p.LastPage, _ = strconv.Atoi(query["page"][0])
+		}
+	}
+
+	p.consumed = true
+
+	var bs []*DictionaryItem
+	if err := decodeBodyMap(resp.Body, &bs); err != nil {
+		return nil, err
+	}
+	sort.Stable(dictionaryItemsByKey(bs))
+
+	return bs, nil
+}
+
 // CreateDictionaryItemInput is used as input to the CreateDictionaryItem function.
 type CreateDictionaryItemInput struct {
 	// ServiceID is the ID of the service (required).

fastly/dictionary_item_test.go

@@ -65,6 +65,28 @@ func TestClient_DictionaryItems(t *testing.T) {
 		t.Errorf("bad dictionary items: %v", dictionaryItems)
 	}
 
+	// List with paginator
+	var dictionaryItems2 []*DictionaryItem
+	var paginator *ListDictionaryItemsPaginator
+	record(t, fixtureBase+"list2", func(c *Client) {
+		paginator = c.NewListDictionaryItemsPaginator(&ListDictionaryItemsInput{
+			ServiceID:    testService.ID,
+			DictionaryID: testDictionary.ID,
+		})
+		dictionaryItems2, err = paginator.GetNext()
+	})
+	if err != nil {
+		t.Fatal(err)
+	}
+
+	if len(dictionaryItems2) != 1 {
+		t.Errorf("Bad items: %v", dictionaryItems2)
+	}
+
+	if paginator.HasNext() {
+		t.Errorf("Bad paginator (remaining: %v)", paginator.Remaining())
+	}
+
 	// Get
 	var retrievedDictionaryItem *DictionaryItem
 	record(t, fixtureBase+"get", func(c *Client) {

fastly/example_acl_entry_test.go

@@ -0,0 +1,34 @@
+package fastly_test
+
+import (
+	"fmt"
+	"log"
+
+	"github.com/fastly/go-fastly/v5/fastly"
+)
+
+func ExampleClient_NewListACLEntriesPaginator() {
+	client, err := fastly.NewClient("your_api_token")
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	paginator := client.NewListACLEntriesPaginator(
+		&fastly.ListACLEntriesInput{
+			ServiceID: "your_service_id",
+			ACLID:     "your_acl_id",
+			PerPage:   50,
+		},
+	)
+
+	var es []*fastly.ACLEntry
+	for paginator.HasNext() {
+		data, err := paginator.GetNext()
+		if err != nil {
+			break
+		}
+		es = append(es, data...)
+	}
+
+	fmt.Printf("retrieved %d ACL entries\n", len(es))
+}