feat(fastestvpn): update servers data using API instead of zip file

- Add city filter - More dynamic to servers updates on fastestvpn's end - Update servers data
2024-07-30 14:50:32 +00:00
parent 8c730a6e4a
commit ab08a5e666
9 changed files with 640 additions and 364 deletions
--- a/internal/provider/fastestvpn/updater/api.go
+++ b/internal/provider/fastestvpn/updater/api.go
@@ -0,0 +1,129 @@
+package updater
+
+import (
+	"bytes"
+	"context"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strings"
+
+	"github.com/qdm12/gluetun/internal/provider/common"
+)
+
+type apiServer struct {
+	country  string
+	city     string
+	hostname string
+}
+
+var (
+	ErrDataMalformed = errors.New("data is malformed")
+)
+
+const apiURL = "https://support.fastestvpn.com/wp-admin/admin-ajax.php"
+
+// The API URL and requests are shamelessly taken from network operations
+// done on the page https://support.fastestvpn.com/vpn-servers/
+func fetchAPIServers(ctx context.Context, client *http.Client, protocol string) (
+	servers []apiServer, err error) {
+	form := url.Values{
+		"action":   []string{"vpn_servers"},
+		"protocol": []string{protocol},
+	}
+	body := strings.NewReader(form.Encode())
+
+	request, err := http.NewRequestWithContext(ctx, http.MethodPost, apiURL, body)
+	if err != nil {
+		return nil, fmt.Errorf("creating request: %w", err)
+	}
+	request.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	// request.Header.Set("User-Agent", "curl/8.9.0")
+	// request.Header.Set("Accept", "*/*")
+
+	response, err := client.Do(request)
+	if err != nil {
+		return nil, fmt.Errorf("sending request: %w", err)
+	}
+
+	if response.StatusCode != http.StatusOK {
+		_ = response.Body.Close()
+		return nil, fmt.Errorf("%w: %d", common.ErrHTTPStatusCodeNotOK, response.StatusCode)
+	}
+
+	data, err := io.ReadAll(response.Body)
+	if err != nil {
+		_ = response.Body.Close()
+		return nil, fmt.Errorf("reading response body: %w", err)
+	}
+
+	err = response.Body.Close()
+	if err != nil {
+		return nil, fmt.Errorf("closing response body: %w", err)
+	}
+
+	const usualMaxNumber = 100
+	servers = make([]apiServer, 0, usualMaxNumber)
+
+	for {
+		trBlock := getNextTRBlock(data)
+		if trBlock == nil {
+			break
+		}
+		data = data[len(trBlock):]
+
+		var server apiServer
+
+		const numberOfTDBlocks = 3
+		for i := 0; i < numberOfTDBlocks; i++ {
+			tdBlock := getNextTDBlock(trBlock)
+			if tdBlock == nil {
+				return nil, fmt.Errorf("%w: expected 3 <td> blocks in <tr> block %q",
+					ErrDataMalformed, string(trBlock))
+			}
+			trBlock = trBlock[len(tdBlock):]
+
+			const startToken, endToken = "<td>", "</td>"
+			tdBlockData := string(tdBlock[len(startToken) : len(tdBlock)-len(endToken)])
+			const countryIndex, cityIndex, hostnameIndex = 0, 1, 2
+			switch i {
+			case countryIndex:
+				server.country = tdBlockData
+			case cityIndex:
+				server.city = tdBlockData
+			case hostnameIndex:
+				server.hostname = tdBlockData
+			}
+		}
+		servers = append(servers, server)
+	}
+
+	return servers, nil
+}
+
+func getNextTRBlock(data []byte) (trBlock []byte) {
+	const startToken, endToken = "<tr>", "</tr>"
+	return getNextBlock(data, startToken, endToken)
+}
+
+func getNextTDBlock(data []byte) (tdBlock []byte) {
+	const startToken, endToken = "<td>", "</td>"
+	return getNextBlock(data, startToken, endToken)
+}
+
+func getNextBlock(data []byte, startToken, endToken string) (nextBlock []byte) {
+	i := bytes.Index(data, []byte(startToken))
+	if i == -1 {
+		return nil
+	}
+
+	nextBlock = data[i:]
+	i = bytes.Index(nextBlock[len(startToken):], []byte(endToken))
+	if i == -1 {
+		return nil
+	}
+	nextBlock = nextBlock[:i+len(startToken)+len(endToken)]
+	return nextBlock
+}