1 files changed, 146 insertions, 0 deletions
diff --git a/backend/internal/ibd/client.go b/backend/internal/ibd/client.go
new file mode 100644
index 0000000..eb3d27e
--- /dev/null
+++ b/backend/internal/ibd/client.go
@@ -0,0 +1,146 @@
+package ibd
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"net/url"
+	"strconv"
+
+	"ibd-trader/internal/database"
+)
+
+var ErrNoAvailableCookies = errors.New("no available cookies")
+
+type Client struct {
+	// HTTP client used to make requests
+	client *http.Client
+	// Scrapfly API key
+	apiKey string
+	// Client-wide Scrape options
+	options ScrapeOptions
+	// Cookie source
+	cookies database.CookieSource
+	// Proxy URL for non-scrapfly requests
+	proxyUrl *url.URL
+}
+
+func NewClient(
+	client *http.Client,
+	apiKey string,
+	cookies database.CookieSource,
+	proxyUrl string,
+	opts ...ScrapeOption,
+) (*Client, error) {
+	options := defaultScrapeOptions
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	pProxyUrl, err := url.Parse(proxyUrl)
+	if err != nil {
+		return nil, err
+	}
+
+	return &Client{
+		client:   client,
+		options:  options,
+		apiKey:   apiKey,
+		cookies:  cookies,
+		proxyUrl: pProxyUrl,
+	}, nil
+}
+
+func (c *Client) getCookie(ctx context.Context, subject *string) (uint, *http.Cookie, error) {
+	if subject == nil {
+		// No subject requirement, get any cookie
+		cookie, err := c.cookies.GetAnyCookie(ctx)
+		if err != nil {
+			return 0, nil, err
+		}
+		if cookie == nil {
+			return 0, nil, ErrNoAvailableCookies
+		}
+
+		return cookie.ID, cookie.ToHTTPCookie(), nil
+	}
+
+	// Get cookie by subject
+	cookies, err := c.cookies.GetCookies(ctx, *subject, false)
+	if err != nil {
+		return 0, nil, err
+	}
+
+	if len(cookies) == 0 {
+		return 0, nil, ErrNoAvailableCookies
+	}
+
+	cookie := cookies[0]
+
+	return cookie.ID, cookie.ToHTTPCookie(), nil
+}
+
+func (c *Client) Do(req *http.Request, opts ...ScrapeOption) (*ScraperResponse, error) {
+	options := c.options
+	for _, opt := range opts {
+		opt(&options)
+	}
+
+	// Construct scrape request URL
+	scrapeUrl, err := url.Parse(options.baseURL)
+	if err != nil {
+		panic(err)
+	}
+	scrapeUrl.RawQuery = c.constructRawQuery(options, req.URL, req.Header)
+
+	// Construct scrape request
+	scrapeReq, err := http.NewRequestWithContext(req.Context(), req.Method, scrapeUrl.String(), req.Body)
+	if err != nil {
+		return nil, err
+	}
+
+	// Send scrape request
+	resp, err := c.client.Do(scrapeReq)
+	if err != nil {
+		return nil, err
+	}
+	defer func(Body io.ReadCloser) {
+		_ = Body.Close()
+	}(resp.Body)
+
+	// Parse scrape response
+	scraperResponse := new(ScraperResponse)
+	err = json.NewDecoder(resp.Body).Decode(scraperResponse)
+	if err != nil {
+		return nil, err
+	}
+
+	return scraperResponse, nil
+}
+
+func (c *Client) constructRawQuery(options ScrapeOptions, u *url.URL, headers http.Header) string {
+	params := url.Values{}
+	params.Set("key", c.apiKey)
+	params.Set("url", u.String())
+	if options.country != nil {
+		params.Set("country", *options.country)
+	}
+	params.Set("asp", strconv.FormatBool(options.asp))
+	params.Set("proxy_pool", options.proxyPool.String())
+	params.Set("render_js", strconv.FormatBool(options.renderJS))
+	params.Set("cache", strconv.FormatBool(options.cache))
+
+	for k, v := range headers {
+		for i, vv := range v {
+			params.Add(
+				fmt.Sprintf("headers[%s][%d]", k, i),
+				vv,
+			)
+		}
+	}
+
+	return params.Encode()
+}