bangs/evaluator/evaluator.go

85 lines
2 KiB
Go

package main
import (
"io/ioutil"
"log"
"net/http"
"net/url"
"regexp"
"strings"
"gopkg.in/yaml.v2"
)
var bangs = loadBangs()
func main() {
http.HandleFunc("/eval", func(w http.ResponseWriter, r *http.Request) {
searchQuery := r.URL.Query().Get("query")
searchEngine := r.URL.Query().Get("engine")
if searchQuery == "" || searchEngine == "" {
http.Error(w, "400 Bad Request", http.StatusBadRequest)
return
}
searchQuery, searchEngine = evaluateBang(searchQuery, searchEngine)
searchURL := buildSearchURL(searchEngine, searchQuery)
http.Redirect(w, r, searchURL, http.StatusSeeOther)
})
log.Fatalf("Failed to start http server: %v", http.ListenAndServe(":8081", nil))
}
func loadBangs() (bangs map[string]string) {
data, err := ioutil.ReadFile("bangs.yml")
if err != nil {
log.Fatalf("Failed to read bangs: %v", err)
}
err = yaml.Unmarshal(data, &bangs)
if err != nil {
log.Fatalf("Failed to decode bangs: %v", err)
}
return
}
func buildSearchURL(template string, query string) (searchUrl string) {
searchUrl = strings.Replace(template, "%s", url.QueryEscape(query), 1)
searchUrl = strings.Replace(searchUrl, "%S", query, 1)
return searchUrl
}
func parseBang(searchQuery string) (bang string, query string) {
regexStartBang, _ := regexp.Compile("\\!(.*) (.*)")
regexEndBang, _ := regexp.Compile("(.*) \\!(.*)")
startBang := regexStartBang.FindSubmatch([]byte(searchQuery))
endBang := regexEndBang.FindSubmatch([]byte(searchQuery))
if len(endBang) == 3 {
bang = strings.ToLower(string(endBang[2]))
query = string(endBang[1])
return
} else if len(startBang) == 3 {
bang = strings.ToLower(string(startBang[1]))
query = string(startBang[2])
return
} else {
return "", searchQuery
}
}
func evaluateBang(searchQuery string, searchEngine string) (query string, engine string) {
bang, query := parseBang(searchQuery)
engine = bangs[bang]
if bang == "" || engine == "" {
return searchQuery, searchEngine
} else {
return query, engine
}
}