refactor: port fetchers to Go

* Austria: upgraded to RIS API v2.6 because v2.5 has been turned off

1 files changed, 90 insertions, 0 deletions

diff --git a/lex-fetch/uk/uk.go b/lex-fetch/uk/uk.go
new file mode 100644
index 0000000..f8e1510
--- /dev/null
+++ b/lex-fetch/uk/uk.go
@@ -0,0 +1,90 @@
+package uk
+
+import (
+	"fmt"
+	"log/slog"
+	"net/http"
+	"regexp"
+	"strconv"
+
+	"github.com/antchfx/xmlquery"
+	"push-f.com/lex-surf/internal/lex"
+	"push-f.com/lex-surf/lex-fetch/progress"
+)
+
+type Fetcher struct{}
+
+func (s *Fetcher) Fetch(log *slog.Logger, client *http.Client, progress *progress.Reporter) ([]lex.Law, error) {
+	firstPage, err := fetchPage(client, 1)
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch first page: %w", err)
+	}
+	progress.Total = firstPage.totalItems / firstPage.itemsPerPage
+
+	laws := firstPage.entries
+
+	for page := 2; page <= progress.Total; page++ {
+		feed, err := fetchPage(client, page)
+		if err != nil {
+			return nil, fmt.Errorf("failed to fetch page: %w", err)
+		}
+		laws = append(laws, feed.entries...)
+		progress.ReportProgress(page)
+	}
+	return laws, nil
+}
+
+func fetchPage(client *http.Client, page int) (*feed, error) {
+	resp, err := client.Get(fmt.Sprintf("https://www.legislation.gov.uk/ukpga/data.feed?page=%d", page))
+	if err != nil {
+		return nil, fmt.Errorf("failed to fetch page: %w", err)
+	}
+	if resp.StatusCode != 200 {
+		return nil, fmt.Errorf("unexpected status code %d", resp.StatusCode)
+	}
+
+	doc, err := xmlquery.Parse(resp.Body)
+	if err != nil {
+		return nil, fmt.Errorf("failed to HTML parse: %w", err)
+	}
+	itemsPerPageEl := xmlquery.FindOne(doc, "//openSearch:itemsPerPage")
+	if itemsPerPageEl == nil {
+		return nil, fmt.Errorf("couldn't find openSearch:itemsPerPage")
+	}
+	itemsPerPage, _ := strconv.Atoi(itemsPerPageEl.InnerText())
+
+	facetTypesEl := xmlquery.FindOne(doc, "//leg:facetType")
+	if facetTypesEl == nil {
+		return nil, fmt.Errorf("couldn't find leg:facetType")
+	}
+	totalItems, _ := strconv.Atoi(facetTypesEl.SelectAttr("value"))
+	if totalItems == 0 {
+		return nil, fmt.Errorf("detected 0 total results")
+	}
+
+	var laws []lex.Law
+
+	for _, entry := range xmlquery.Find(doc, "//entry") {
+		title := xmlquery.FindOne(entry, "./title").InnerText()
+		repealed, _ := regexp.MatchString("(?i)\\(repealed( .+)?\\)$", title)
+		if repealed {
+			continue
+		}
+		laws = append(laws, lex.Law{
+			Title: title,
+			URL:   xmlquery.FindOne(entry, "./link[@rel='self']").SelectAttr("href"),
+		})
+	}
+
+	return &feed{
+		totalItems:   totalItems,
+		itemsPerPage: itemsPerPage,
+		entries:      laws,
+	}, nil
+}
+
+type feed struct {
+	itemsPerPage int
+	totalItems   int
+	entries      []lex.Law
+}