First working version

bill.go

@@ -1,44 +1,95 @@
 package qiwiP2P
 
 import (
+	"encoding/json"
 	"fmt"
 	"time"
 )
 
 type Bill struct {
-	Currency string
-	Value float32
-	Comment string
-	ExpirationDateTime time.Time
-	CustomerPhone string
-	CustomerEmail string
-	CustomerAccount string
-	CustomFields map[string]string
+	Amount             Amount            `json:"amount"`
+	Comment            string            `json:"comment"`
+	ExpirationDateTime string            `json:"expirationDateTime"`
+	Customer           Customer          `json:"customer"`
+	CustomFields       map[string]string `json:"customFields"`
+}
+
+type Amount struct {
+	Currency string `json:"currency"`
+	Value    string `json:"value"`
+}
+
+type Status struct {
+	Value           string `json:"value"`
+	ChangedDateTime string `json:"changedDateTime"`
+}
+
+type Customer struct {
+	Phone   string `json:"phone"`
+	Email   string `json:"email"`
+	Account string `json:"account"`
 }
 
 func CreateBill() *Bill {
 	return &Bill{
-		Currency: "RUB",
-		Value: 1,
-		ExpirationDateTime: time.Now().UTC().Add(time.Hour * 3),
+		Amount:             Amount{},
+		Customer:           Customer{},
+		ExpirationDateTime: time.Now().UTC().Add(time.Hour * 3).Format("2006-01-02T15:01:05+00:00"),
+		CustomFields:       make(map[string]string),
 	}
 }
 
+func (b *Bill) SetTheme(theme string) *Bill {
+	b.CustomFields["themeCode"] = theme
+	return b
+}
+
+func (b *Bill) SetPaySourcesFilter(filter string) *Bill {
+	b.CustomFields["paySourcesFilter"] = filter
+	return b
+}
+
 func (b *Bill) SetCurrency(currency string) *Bill {
-	b.Currency = currency
+	b.Amount.Currency = currency
 	return b
 }
 
 func (b *Bill) SetValue(value float32) *Bill {
-	b.Value = value
+	b.Amount.Value = fmt.Sprintf("%.2f", value)
+	return b
+}
+
+func (b *Bill) SetComment(comment string) *Bill {
+	b.Comment = comment
+	return b
+}
+
+func (b *Bill) SetExpirationDateTime(time time.Time) *Bill {
+	b.ExpirationDateTime = time.UTC().Format("2006-01-02T15:01:05+00:00")
+	return b
+}
+
+func (b *Bill) SetCustomerPhone(phone string) *Bill {
+	b.Customer.Phone = phone
+	return b
+}
+
+func (b *Bill) SetCustomerEmail(email string) *Bill {
+	b.Customer.Email = email
+	return b
+}
+
+func (b *Bill) SetCustomerAccount(account string) *Bill {
+	b.Customer.Account = account
+	return b
+}
+
+func (b *Bill) SetCustomField(field string, value string) *Bill {
+	b.CustomFields[field] = value
 	return b
 }
 
 func (b *Bill) toJSON() string {
-	return fmt.Sprintf(
-		"{\"amount\":{\"currency\":\"%s\",\"value\": \"%.2f\"}," +
-			"\"expirationDateTime\": \"%s\"}",
-			b.Currency,
-			b.Value,
-			b.ExpirationDateTime.Format("2006-01-02T15:01:05+00:00"))
+	arr, _ := json.Marshal(b)
+	return string(arr)
 }

billResponse.go

@@ -0,0 +1,23 @@
+package qiwiP2P
+
+type BillResponse struct {
+	SiteId             string            `json:"siteId"`
+	BillId             string            `json:"billId"`
+	Amount             Amount            `json:"amount"`
+	Status             Status            `json:"status"`
+	Customer           Customer          `json:"customer"`
+	CustomFields       map[string]string `json:"customFields"`
+	Comment            string            `json:"comment"`
+	CreationDateTime   string            `json:"creationDateTime"`
+	ExpirationDateTime string            `json:"expirationDateTime"`
+	PayUrl             string            `json:"payUrl"`
+}
+
+type RequestError struct {
+	ServiceName string `json:"serviceName"`
+	ErrorCode   string `json:"errorCode"`
+	Description string `json:"description"`
+	UserMessage string `json:"userMessage"`
+	DateTime    string `json:"dateTime"`
+	TraceId     string `json:"traceId"`
+}

client.go

@@ -2,6 +2,7 @@ package qiwiP2P
 
 import (
 	"crypto/rand"
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
@@ -22,24 +23,69 @@ func (c *Client) SetSecretKey(key string) *Client {
 	return c
 }
 
-func (c *Client) PutBill(b *Bill) (json string, retErr error) {
+func (c *Client) PutBill(b *Bill) (result *BillResponse, error *RequestError) {
 	billId := pseudoUUID()
-	req, err := http.NewRequest(
-		"PUT", "https://api.qiwi.com/partner/bill/v1/bills/"+billId, strings.NewReader(b.toJSON()),
-	)
-	if err != nil {
-		return "", err
+	res, code := c.makeRequest("https://api.qiwi.com/partner/bill/v1/bills/"+billId, "PUT", b.toJSON())
+
+	if code == 401 {
+		return nil, &RequestError{ErrorCode: "bad_token", Description: "Bad token"}
 	}
-	req.Header.Add("Authorization", "Bearer "+c.token)
-	req.Header.Add("User-Agent", "GoQiwiP2P")
-	res, err := c.client.Do(req)
-	if err != nil {
-		return "", err
+
+	return parseResponse(res)
+}
+
+func (c *Client) GetBill(id string) (result *BillResponse, error *RequestError) {
+	res, code := c.makeRequest("https://api.qiwi.com/partner/bill/v1/bills/"+id, "GET", "")
+
+	if code == 401 {
+		return nil, &RequestError{ErrorCode: "bad_token", Description: "Bad token"}
+	}
+	if code == 404 {
+		return nil, &RequestError{ErrorCode: "bad_id", Description: "No such bill found"}
+	}
+
+	return parseResponse(res)
+}
+
+func (c *Client) RejectBill(id string) (result *BillResponse, error *RequestError) {
+	res, code := c.makeRequest("https://api.qiwi.com/partner/bill/v1/bills/"+id+"/reject", "POST", "")
+
+	if code == 401 {
+		return nil, &RequestError{ErrorCode: "bad_token", Description: "Bad token"}
 	}
+	if code == 404 {
+		return nil, &RequestError{ErrorCode: "bad_id", Description: "No such bill found"}
+	}
+
+	return parseResponse(res)
+}
+
+func parseResponse(jsonResponse string) (result *BillResponse, error *RequestError) {
+	var re RequestError
+	json.Unmarshal([]byte(jsonResponse), &error)
+	if re.ErrorCode != "" {
+		return nil, &re
+	}
+
+	var response BillResponse
+	json.Unmarshal([]byte(jsonResponse), &response)
+
+	return &response, nil
+}
+
+func (c *Client) makeRequest(url string, method string, data string) (json string, code int) {
+	req, _ := http.NewRequest(
+		method, url, strings.NewReader(data),
+	)
+
+	req.Header.Add("Authorization", "Bearer "+c.token)
+	req.Header.Add("content-type", "application/json")
+	res, _ := c.client.Do(req)
+
+	defer res.Body.Close()
 	buf := new(strings.Builder)
 	io.Copy(buf, res.Body)
-
-	return buf.String(), nil
+	return buf.String(), res.StatusCode
 }
 
 func pseudoUUID() (uuid string) {