ynab-portfolio-monitor/ynab/client.go

144 lines
4.0 KiB
Go

package ynab
import (
"bytes"
"encoding/json"
"fmt"
"io"
"net/http"
"net/url"
"time"
)
// Reference: https://api.ynab.com/
const apiBaseURL = "https://api.ynab.com/v1/budgets/"
// A client is the structure that will be used to consume the API
// endpoints. It holds the login credentials, http client/transport,
// rate limit information, and the login session timer.
type Client struct {
BearerToken string
BudgetID string
httpClient *http.Client
transport *http.Transport
}
// Send an HTTP GET request, and return the processed response
func (c *Client) get(endpoint string, out interface{}, query url.Values) error {
req, err := http.NewRequest("GET", apiBaseURL+c.BudgetID+endpoint+"?"+query.Encode(), nil)
if err != nil {
return fmt.Errorf("failed to create new GET request: %v", err)
}
req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", c.BearerToken))
res, err := c.httpClient.Do(req)
if err != nil {
return fmt.Errorf("http GET request failed: %v", err)
}
err = c.processResponse(res, out)
if err != nil {
return fmt.Errorf("failed to process response: %v", err)
}
return nil
}
// Format the message body, send an HTTP POST request, and return the processed response
func (c *Client) post(endpoint string, out interface{}, body interface{}) error {
// Attempt to marshall the body as JSON
json, err := json.Marshal(body)
if err != nil {
return fmt.Errorf("failed to marshal body to json: %v", err)
}
req, err := http.NewRequest("POST", apiBaseURL+c.BudgetID+endpoint, bytes.NewBuffer(json))
if err != nil {
return fmt.Errorf("failed to create new POST request: %v", err)
}
req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", c.BearerToken))
req.Header.Add("Content-Type", "application/json")
res, err := c.httpClient.Do(req)
if err != nil {
return fmt.Errorf("http POST request failed: %v", err)
}
err = c.processResponse(res, out)
if err != nil {
return fmt.Errorf("failed to process response: %v", err)
}
return nil
}
// Format the message body, send an HTTP POST request, and return the processed response
func (c *Client) put(endpoint string, out interface{}, body interface{}) error {
// Attempt to marshall the body as JSON
json, err := json.Marshal(body)
if err != nil {
return fmt.Errorf("failed to marshal body to json: %v", err)
}
req, err := http.NewRequest("PUT", apiBaseURL+c.BudgetID+endpoint, bytes.NewBuffer(json))
if err != nil {
return fmt.Errorf("failed to create new POST request: %v", err)
}
req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", c.BearerToken))
req.Header.Add("Content-Type", "application/json")
res, err := c.httpClient.Do(req)
if err != nil {
return fmt.Errorf("http POST request failed: %v", err)
}
err = c.processResponse(res, out)
if err != nil {
return fmt.Errorf("failed to process response: %v", err)
}
return nil
}
// processResponse takes the body of an HTTP response, and either returns
// the error code, or unmarshalls the JSON response, extracts
// rate limit info, and places it into the object
// output parameter. This function closes the response body after reading it.
func (c *Client) processResponse(res *http.Response, out interface{}) error {
body, err := io.ReadAll(res.Body)
res.Body.Close()
if err != nil {
return fmt.Errorf("failed to read response body: %v", err)
}
if res.StatusCode != 200 && res.StatusCode != 201 {
return fmt.Errorf("unexpected http status code '%d': %v", res.StatusCode, err)
}
err = json.Unmarshal(body, out)
if err != nil {
return fmt.Errorf("failed to unmarshal response body: %v", err)
}
return nil
}
// NewClient is the factory function for clients - takes a bearer token
func NewClient(budgetID, bearerToken string) (*Client, error) {
transport := &http.Transport{
ResponseHeaderTimeout: 5 * time.Second,
}
client := &http.Client{
Transport: transport,
}
// Create a new client
c := &Client{
BudgetID: budgetID,
BearerToken: bearerToken,
httpClient: client,
transport: transport,
}
return c, nil
}