Open Library search API

If nothing is found on the server, returns results from open library
API. Clicking on a book imports it.

internal/openlibrary/openlibrarybook.go

@@ -0,0 +1,93 @@
+package openlibrary
+
+import (
+	"encoding/json"
+	"fmt"
+	"strings"
+)
+
+type OpenLibraryBookResult struct {
+	Title       string `json:"title"`
+	Description string `json:"description"`
+	AuthorID    string `json:"author_id"`
+}
+
+type openLibraryParsedBook struct {
+	Title       string                        `json:"title"`
+	Description string                        `json:"description"`
+	AuthorInfo  []openLibraryBookAuthorResult `json:"authors"`
+}
+
+type openLibraryBookAuthorResult struct {
+	AuthorOLID string
+	Type       string
+	Key        string
+}
+
+type keyContainer struct {
+	Key string `json:"key"`
+}
+
+func (r *openLibraryBookAuthorResult) UnmarshalJSON(data []byte) error {
+
+	var parentAuthor struct {
+		AuthorKey keyContainer `json:"author"`
+		TypeKey   keyContainer `json:"type"`
+		Key       string       `json:"key"`
+	}
+
+	if err := json.Unmarshal(data, &parentAuthor); err != nil {
+		return err
+	}
+	r.AuthorOLID = parseUrlPathToField(parentAuthor.AuthorKey.Key)
+	r.Type = parseUrlPathToField(parentAuthor.TypeKey.Key)
+	r.Key = parseUrlPathToField(parentAuthor.Key)
+	return nil
+}
+
+// some fields follow this format "/authors/OL274606A"
+// this method extracts the last part "OL274606A"
+func parseUrlPathToField(urlpath string) string {
+	splittedPath := strings.Split(urlpath, "/")
+	if len(splittedPath) > 2 {
+		return splittedPath[2]
+	} else {
+		return urlpath
+	}
+}
+
+func CallOpenLibraryBook(openLibraryId string) (OpenLibraryBookResult, error) {
+	var response OpenLibraryBookResult
+	u, err := computeOpenLibraryUrl("works", fmt.Sprintf("%s.json", openLibraryId))
+	if err != nil {
+		return response, err
+	}
+	var queryResult openLibraryParsedBook
+	err = fetchAndParseResult(u, &queryResult)
+	if err != nil {
+		return response, err
+	}
+	author := computeAuthorFromParsedBook(&queryResult)
+	response = OpenLibraryBookResult{
+		Title:       queryResult.Title,
+		Description: queryResult.Description,
+		AuthorID:    author,
+	}
+	return response, err
+}
+
+func computeAuthorFromParsedBook(parsedBook *openLibraryParsedBook) string {
+	authors := parsedBook.AuthorInfo
+	for _, author := range authors {
+		if author.Key != "" {
+			return author.Key
+		}
+		if author.Type == "author_role" {
+			return author.AuthorOLID
+		}
+	}
+	if len(authors) > 0 {
+		return authors[0].AuthorOLID
+	}
+	return ""
+}