initial commit

internal/netbox/api.go

@@ -0,0 +1,111 @@
+package netbox
+
+import (
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/url"
+)
+
+type APIRequestClient struct {
+	Client    *http.Client
+	NetboxURL *url.URL
+	Token     string
+	UserAgent string
+}
+
+type APIResultModel interface {
+	Record | Zone
+}
+
+type APIManyResponse[T APIResultModel] struct {
+	Count    int    `json:"count"`
+	Next     string `json:"next"`
+	Previous string `json:"previous"`
+	Results  []T    `json:"results"`
+}
+
+func doGet(
+	requestClient *APIRequestClient,
+	url string,
+) (*http.Response, error) {
+	request, err := http.NewRequest("GET", url, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	request.Header.Set(
+		"Authorization",
+		fmt.Sprintf("Token %s", requestClient.Token),
+	)
+
+	request.Header.Set("User-Agent", requestClient.UserAgent)
+
+	return requestClient.Client.Do(request)
+}
+
+func responseError(response *http.Response) error {
+	if response.StatusCode != http.StatusOK {
+		return fmt.Errorf(
+			"request error [%d] %q",
+			response.StatusCode,
+			response.Status,
+		)
+	}
+	return nil
+}
+
+func get[T APIResultModel](
+	requestClient *APIRequestClient,
+	url string,
+) (T, error) {
+	var out T
+	response, err := doGet(requestClient, url)
+	if err != nil {
+		return out, err
+	}
+	defer response.Body.Close()
+	if err := responseError(response); err != nil {
+		return out, err
+	}
+	decoder := json.NewDecoder(response.Body)
+	if err := decoder.Decode(&out); err != nil {
+		return out, fmt.Errorf("could not unmarshal response: %w", err)
+	}
+	return out, nil
+}
+
+func getMany[T APIResultModel](
+	requestClient *APIRequestClient,
+	url string,
+) ([]T, error) {
+	nextUrl := url
+	var out []T
+
+	for nextUrl != "" {
+		response, err := doGet(requestClient, nextUrl)
+		if err != nil {
+			return out, err
+		}
+		defer response.Body.Close()
+
+		if err := responseError(response); err != nil {
+			return out, err
+		}
+
+		var apiResponse APIManyResponse[T]
+		decoder := json.NewDecoder(response.Body)
+		if err := decoder.Decode(&apiResponse); err != nil {
+			return out, fmt.Errorf("could not unmarshal response: %w", err)
+		}
+
+		if out == nil {
+			out = make([]T, 0, apiResponse.Count)
+		}
+		out = append(out, apiResponse.Results...)
+
+		nextUrl = apiResponse.Next
+	}
+
+	return out, nil
+}