我正在研究使用 golang 作为后端的 Web 开发。我有一个 API，我需要从中获取数据。
我所做的是创建一个常量来保存 URL，如下所示：
const (
locationsURL = "https://groupietrackers.herokuapp.com/api/locations"
)
然后我创建了结构：
type LocationData struct {
Locations []string `json:"locations"`
}
然后我创建了一个函数来从 URl 获取数据
func fetchDataFromURL(url string, target interface{}) error {
response, err := http.Get(url)
if err != nil {
return err
}
defer response.Body.Close()
if response.StatusCode != http.StatusOK {
return fmt.Errorf("failed to fetch data, status code: %d", response.StatusCode)
}
// Read the response body
responseBody, err := ioutil.ReadAll(response.Body)
if err != nil {
return fmt.Errorf("failed to read response body: %v", err)
}
// Print the response body for inspection
//fmt.Println("Response Body:", string(responseBody))
// Decode the response body into the target interface
err = json.Unmarshal(responseBody, target)
if err != nil {
return fmt.Errorf("failed to decode response body: %v", err)
}
return nil
}
之后是获取位置结构数据的函数：
func getLocationData() ([]LocationData, error) {
var locations []LocationData
err := fetchDataFromURL(locationsURL, &locations)
if err != nil {
return nil, err
}
fmt.Println("Location data:", locations)
return locations, nil
}
我创建了 home Handler 函数：
func homeHandler(w http.ResponseWriter, r *http.Request) {
artists, err := getArtistData()
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
fmt.Println("Error fetching artist data from URL")
return
}
locations, err := getLocationData()
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
fmt.Println("Error fetching location data from URL", err)
return
}
tmpl, err := template.ParseFiles("index.html")
if err != nil {
http.Error(w, "Internal server error", http.StatusInternalServerError)
fmt.Println("Error parsing template: ", err)
return
}
data := struct {
Artists []Artist
Locations []LocationData
}{
Artists: artists,
Locations: locations,
}
err = tmpl.Execute(w, data)
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
fmt.Println("Error executing template: ", err)
return
}
if r.URL.Path != "/" {
http.Error(w, "404: Page not found", http.StatusNotFound)
}
}
当我运行它时，我收到此错误
failed to decode response body: json: cannot unmarshal object into Go value of type []main.LocationData
我检查了 json 文件数据的位置，它是相同的，这是 json 文件的示例
"locations":["north_carolina-usa","georgia-usa","los_angeles-usa","saitama-japan","osaka-japan","nagoya-japan","penrose-new_zealand","dunedin-new_zealand"]
任何人都可以帮助我吗:)
示例程序被解组为
[]LocationDataLocationDataLocations []string这是一个工作示例，从您提供的 URL 中解析最小值：
package main
import (
"encoding/json"
"fmt"
)
type Root struct {
Index []Index `json:"index"`
}
type Index struct {
Locations []string `json:"locations"`
}
func main() {
var root Root
if err := json.Unmarshal([]byte(output), &root); err != nil {
panic(err)
}
fmt.Printf("entries: %d\n", len(root.Index))
}
const output = `{"index":[{"id":1,"locations":["north_carolina-usa","georgia-usa","los_angeles-usa","saitama-japan","osaka-japan","nagoya-japan","penrose-new_zealand","dunedin-new_zealand"],"dates":"https://groupietrackers.herokuapp.com/api/dates/1"},{"id":2,"locations":["playa_del_carmen-mexico","papeete-french_polynesia","noumea-new_caledonia"],"dates":"https://groupietrackers.herokuapp.com/api/dates/2"},{"id":3,"locations":["london-uk","lausanne-switzerland","lyon-france"],"dates":"https://groupietrackers.herokuapp.com/api/dates/3"},{"id":4,"locations":["victoria-australia","new_south_wales-australia","queensland-australia","auckland-new_zealand","yogyakarta-indonesia","bratislava-slovakia","budapest-hungary","minsk-belarus"],"dates":"https://groupietrackers.herokuapp.com/api/dates/4"},{"id":5,"locations":["california-usa","nevada-usa","georgia-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/5"},{"id":6,"locations":["california-usa","sao_paulo-brazil","san_isidro-argentina"],"dates":"https://groupietrackers.herokuapp.com/api/dates/6"},{"id":7,"locations":["california-usa","arizona-usa","texas-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/7"},{"id":8,"locations":["stockholm-sweden","werchter-belgium","lisbon-portugal","bilbao-spain","georgia-usa","bogota-colombia","sao_paulo-brazil"],"dates":"https://groupietrackers.herokuapp.com/api/dates/8"},{"id":9,"locations":["new_york-usa","dusseldorf-germany","aarhus-denmark","manchester-uk"],"dates":"https://groupietrackers.herokuapp.com/api/dates/9"},{"id":10,"locations":["frankfurt-germany","berlin-germany","stockholm-sweden","copenhagen-denmark","werchter-belgium"],"dates":"https://groupietrackers.herokuapp.com/api/dates/10"},{"id":11,"locations":["doha-qatar","minnesota-usa","illinois-usa","california-usa","mumbai-india"],"dates":"https://groupietrackers.herokuapp.com/api/dates/11"},{"id":12,"locations":["abu_dhabi-united_arab_emirates","new_york-usa","pennsylvania-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/12"},{"id":13,"locations":["westcliff_on_sea-uk","merkers-germany","illinois-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/13"},{"id":14,"locations":["nevada-usa","arizona-usa","california-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/14"},{"id":15,"locations":["london-uk","new_york-usa","maine-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/15"},{"id":16,"locations":["berlin-germany","copenhagen-denmark","aarhus-denmark","gothenburg-sweden"],"dates":"https://groupietrackers.herokuapp.com/api/dates/16"},{"id":17,"locations":["florida-usa","south_carolina-usa","north_carolina-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/17"},{"id":18,"locations":["pagney_derriere_barine-france","hamburg-germany","boulogne_billancourt-france","nimes-france","sion-switzerland","ostrava-czechia","klagenfurt-austria","freyming_merlebach-france"],"dates":"https://groupietrackers.herokuapp.com/api/dates/18"},{"id":19,"locations":["nevada-usa","london-uk","manchester-uk"],"dates":"https://groupietrackers.herokuapp.com/api/dates/19"},{"id":20,"locations":["zaragoza-spain","madrid-spain","barcelona-spain"],"dates":"https://groupietrackers.herokuapp.com/api/dates/20"},{"id":21,"locations":["rio_de_janeiro-brazil","recife-brazil"],"dates":"https://groupietrackers.herokuapp.com/api/dates/21"},{"id":22,"locations":["california-usa","leipzig-germany","salem-germany","monchengladbach-germany","cuxhaven-germany","skanderborg-denmark","amsterdam-netherlands","burriana-spain","oulu-finland","budapest-hungary","napoca-romania"],"dates":"https://groupietrackers.herokuapp.com/api/dates/22"},{"id":23,"locations":["riyadh-saudi_arabia","rio_de_janeiro-brazil","canton-usa","quebec-canada","new_york-usa","california-usa","las_vegas-usa","mexico_city-mexico","monterrey-mexico","del_mar-usa","berlin-germany","lisbon-portugal"],"dates":"https://groupietrackers.herokuapp.com/api/dates/23"},{"id":24,"locations":["washington-usa","west_melbourne-australia","amsterdam-netherlands","paris-france","manchester-uk","missouri-usa","chicago-usa","birmingham-uk","copenhagen-denmark"],"dates":"https://groupietrackers.herokuapp.com/api/dates/24"},{"id":25,"locations":["west_melbourne-australia","sydney-australia","madison-usa","toronto-canada","cleveland-usa","new_york-usa","boston-usa","texas-usa","utah-usa","california-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/25"},{"id":26,"locations":["manchester-uk","glasgow-uk","dublin-ireland","cardiff-uk","london-uk","aberdeen-uk","stockholm-sweden","madrid-spain","paris-france","warsaw-poland","berlin-germany","milan-italy"],"dates":"https://groupietrackers.herokuapp.com/api/dates/26"},{"id":27,"locations":["michigan-usa","new_hampshire-usa","new_york-usa","warsaw-poland","sochaux-france","lyon-france","eindhoven-netherlands","oslo-norway","amsterdam-netherlands","colorado-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/27"},{"id":28,"locations":["jakarta-indonesia","huizhou-china","texas-usa","michigan-usa","changzhou-china","hong_kong-china","colorado-usa","sanya-china","aalborg-denmark","washington-usa","new_york-usa","toronto-canada","seattle-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/28"},{"id":29,"locations":["omaha-usa","kansas_city-usa","st_louis-usa","indianapolis-usa","rosemont-usa","grand_rapids-usa","toronto-usa","montreal-usa","newark-usa","uniondale-usa","philadelphia-usa","hershey-usa","pittsburgh-usa","washington-usa","columbia-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/29"},{"id":30,"locations":["santiago-chile","sao_paulo-brazil","los_angeles-usa","houston-usa","atlanta-usa","new_orleans-usa","philadelphia-usa","london-uk","frauenfeld-switzerland","turku-finland"],"dates":"https://groupietrackers.herokuapp.com/api/dates/30"},{"id":31,"locations":["las_vegas-usa","brooklyn-usa","boston-usa","washington-usa","philadelphia-usa","montreal-canada","toronto-usa","new_york-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/31"},{"id":32,"locations":["frankfurt-germany","berlin-germany","stockholm-sweden","copenhagen-denmark","imola-italy","vienna-austria","london-uk","krakow-poland","budapest-hungary","zurich-switzerland"],"dates":"https://groupietrackers.herokuapp.com/api/dates/32"},{"id":33,"locations":["philadelphia-usa","paris-france","amityville-usa","chicago-usa","minneapolis-usa","detroit-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/33"},{"id":34,"locations":["oakland-usa","charlotte-usa","los_angeles-usa","berlin-germany","houston-usa","chicago-usa","inglewood-usa","madrid-spain"],"dates":"https://groupietrackers.herokuapp.com/api/dates/34"},{"id":35,"locations":["windsor-canada","brooklyn-usa","birmingham-uk","cincinnati-usa","anaheim-usa","chicago-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/35"},{"id":36,"locations":["manila-philippines","mumbai-india","auckland-new_zealand","brisbane-australia","melbourne-australia","sydney-australia"],"dates":"https://groupietrackers.herokuapp.com/api/dates/36"},{"id":37,"locations":["bogota-colombia","rio_de_janeiro-brazil","sao_paulo-brazil","santiago-chile","san_isidro-argentina","lima-peru"],"dates":"https://groupietrackers.herokuapp.com/api/dates/37"},{"id":38,"locations":["paris-france","groningen-netherlands","antwerp-belgium","vienna-austria","glasgow-uk","london-uk"],"dates":"https://groupietrackers.herokuapp.com/api/dates/38"},{"id":39,"locations":["mexico_city-mexico","pico_rivera-usa","chicago-usa","boston-usa","philadelphia-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/39"},{"id":40,"locations":["london-uk","berwyn-usa","georgia-usa","new_york-usa","dallas-usa","houston-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/40"},{"id":41,"locations":["california-usa","birmingham-uk","brixton-uk","london-uk","rotselaar-belgium"],"dates":"https://groupietrackers.herokuapp.com/api/dates/41"},{"id":42,"locations":["california-usa","rio_de_janeiro-brazil","los_angeles-usa","alabama-usa","massachusetts-usa","athens-greece","florence-italy","landgraaf-netherlands"],"dates":"https://groupietrackers.herokuapp.com/api/dates/42"},{"id":43,"locations":["sydney-australia","melbourne-australia","burswood-australia","wellington-new_zealand","abu_dhabi-united_arab_emirates"],"dates":"https://groupietrackers.herokuapp.com/api/dates/43"},{"id":44,"locations":["madrid-spain","seville-spain","los_angeles-usa","bangkok-thailand","manila-philippines","taipei-taiwan","hong_kong-china","seoul-south_korea"],"dates":"https://groupietrackers.herokuapp.com/api/dates/44"},{"id":45,"locations":["munich-germany","mannheim-germany","san_francisco-usa","santiago-chile","buenos_aires-argentina","porto_alegre-brazil","sao_paulo-brazil","belo_horizonte-brazil"],"dates":"https://groupietrackers.herokuapp.com/api/dates/45"},{"id":46,"locations":["california-usa","sao_paulo-brazil","porto_alegre-brazil","la_plata-argentina","london-uk"],"dates":"https://groupietrackers.herokuapp.com/api/dates/46"},{"id":47,"locations":["dubai-united_arab_emirates","willemstad-netherlands_antilles","florida-usa","florida-usa","mexico_city-mexico","santiago-chile","sao_paulo-brazil","brasilia-brazil"],"dates":"https://groupietrackers.herokuapp.com/api/dates/47"},{"id":48,"locations":["texas-usa","oklahoma-usa","california-usa","illinois-usa","scheessel-germany","st_gallen-switzerland","gdynia-poland","arras-france"],"dates":"https://groupietrackers.herokuapp.com/api/dates/48"},{"id":49,"locations":["washington-usa","california-usa","california-usa","arizona-usa","florida-usa"],"dates":"https://groupietrackers.herokuapp.com/api/dates/49"},{"id":50,"locations":["mexico_city-mexico","sao_paulo-brazil","buenos_aires-argentina","santiago-chile","lima-peru"],"dates":"https://groupietrackers.herokuapp.com/api/dates/50"},{"id":51,"locations":["bogota-colombia","san_jose-costa_rica","nevada-usa","massachusetts-usa","massachusetts-usa","nickelsdorf-austria","milan-italy","lisbon-portugal"],"dates":"https://groupietrackers.herokuapp.com/api/dates/51"},{"id":52,"locations":["oregon-usa","vancouver-canada","nevada-usa","colorado-usa","munich-germany","prague-czechia","milan-italy"],"dates":"https://groupietrackers.herokuapp.com/api/dates/52"}]}`
// output: entries: 52