golang port

Author: atomotic

Dockerfile

@@ -0,0 +1,14 @@
+
+FROM golang:alpine AS builder
+WORKDIR /go/src/app
+COPY . .
+RUN apk add --no-cache git
+RUN go get -d -v ./...
+RUN go install -v ./...
+
+FROM alpine:latest
+RUN apk --no-cache add ca-certificates
+COPY --from=builder /go/bin/app /app
+ENTRYPOINT ./app
+LABEL Name=isbn-authors Version=1.0.0
+EXPOSE 8093

Procfile

@@ -3,23 +3,7 @@ simple http wrapper around [OCLC Classify](http://classify.oclc.org/classify2/ap
 
 run:
 
-	~ git clone https://github.com/atomotic/isbn-authors
-	~ cd isbn-authors
-	~ pip install -r requirements.txt
+	docker run -d -p 8093:8093 atomotic/isbn-authors 
 
-	# install redis, used to cache results.
-	# apt-get install redis-server (linux)
-	# brew install redis (macos)
-	~ redis-server 
-	
-	~ FLASK_APP=app.py FLASK_DEBUG=1 flask run
-
-	~ http :5000/api/v1/authors/{ISBN}
-
----
 
-examples at:
-[https://isbn-authors.herokuapp.com](https://isbn-authors.herokuapp.com/)
 
-* https://isbn-authors.herokuapp.com/api/v1/authors/9788806189877
-* https://isbn-authors.herokuapp.com/api/v1/authors/9788845930874

README.md

@@ -0,0 +1,137 @@
+package main
+
+import (
+	"encoding/json"
+	"encoding/xml"
+	"errors"
+	"fmt"
+	"io/ioutil"
+	"log"
+	"net/http"
+	"strings"
+
+	"github.com/gorilla/mux"
+	"github.com/knakk/sparql"
+	bolt "go.etcd.io/bbolt"
+)
+
+var db *bolt.DB
+
+const oclcAPI = "http://classify.oclc.org/classify2/Classify?isbn="
+
+type Book struct {
+	Work     Work     `xml:"work" json:"book"`
+	Response Response `xml:"response" json:"-"`
+	Authors  []Author `xml:"authors>author" json:"authors"`
+}
+type Work struct {
+	Title string `xml:"title,attr" json:"title"`
+}
+type Response struct {
+	Code int `xml:"code,attr" json:"-"`
+}
+type Author struct {
+	Viaf     string `xml:"viaf,attr" json:"viaf"`
+	Wikidata string `json:"wikidata"`
+	Text     string `xml:",chardata" json:"name"`
+}
+
+func getBookAuthors(isbn string) (Book, error) {
+	var book Book
+
+	resp, err := http.Get(fmt.Sprintf("%s%s", oclcAPI, isbn))
+	if err != nil {
+		return book, err
+	}
+	defer resp.Body.Close()
+	body, err := ioutil.ReadAll(resp.Body)
+
+	err = xml.Unmarshal([]byte(body), &book)
+	if err != nil {
+		return book, err
+	}
+
+	if book.Response.Code == 0 || book.Response.Code == 2 || book.Response.Code == 4 {
+		for i, author := range book.Authors {
+			wd, err := sparql.NewRepo("https://query.wikidata.org/sparql")
+			if err != nil {
+				return book, err
+			}
+			query := fmt.Sprintf("SELECT ?q WHERE { ?q wdt:P214 '%s'.}", author.Viaf)
+			res, err := wd.Query(query)
+			if err != nil {
+				return book, err
+			}
+			if len(res.Results.Bindings) > 0 {
+				Q := strings.Split(res.Results.Bindings[0]["q"].Value, "/")[4]
+				book.Authors[i].Wikidata = Q
+			}
+		}
+		return book, nil
+	} else {
+		return book, errors.New("0 results.")
+	}
+
+}
+
+func IsbnAPI(w http.ResponseWriter, r *http.Request) {
+	vars := mux.Vars(r)
+	isbn := vars["isbn"]
+
+	err := db.Update(func(tx *bolt.Tx) error {
+
+		b := tx.Bucket([]byte("books"))
+
+		cached := b.Get([]byte(isbn))
+
+		if cached != nil {
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			fmt.Fprintf(w, "%s", cached)
+		} else {
+			book, err := getBookAuthors(isbn)
+			if err != nil {
+				w.WriteHeader(http.StatusNotFound)
+				fmt.Fprintf(w, "<book not found>")
+				return nil
+			}
+
+			bookJSON, _ := json.Marshal(book)
+			err = b.Put([]byte(isbn), []byte(bookJSON))
+			if err != nil {
+				return err
+			}
+			w.Header().Set("Content-Type", "application/json")
+			w.WriteHeader(http.StatusOK)
+			fmt.Fprintf(w, "%s", bookJSON)
+		}
+		return nil
+	})
+	if err != nil {
+		http.Error(w, err.Error(), http.StatusInternalServerError)
+	}
+}
+
+func main() {
+	var err error
+	db, err = bolt.Open("isbn-authors.cache", 0600, nil)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer db.Close()
+
+	db.Update(func(tx *bolt.Tx) error {
+		_, err := tx.CreateBucket([]byte("books"))
+		if err != nil {
+			return fmt.Errorf("create bucket: %s", err)
+		}
+		return nil
+	})
+
+	r := mux.NewRouter()
+	r.HandleFunc("/isbn/{isbn}", IsbnAPI)
+	fmt.Println("server running on http://localhost:8093/isbn/{$ISBN}")
+
+	http.ListenAndServe(":8093", r)
+
+}