client.go

// Copyright (c) 2018, Randy Westlund. All rights reserved.
// This code is under the BSD-2-Clause license.

/*
Package quickbooks provides access to Intuit's QuickBooks Online API.

NOTE: This library is very incomplete. I just implemented the minimum for my
use case. Pull requests welcome :)

 // Do this after you go through the normal OAuth process.
 var client = oauth2.NewClient(ctx, tokenSource)

 // Initialize the client handle.
 var qb = quickbooks.Client{
	 Client: client,
	 Endpoint: quickbooks.SandboxEndpoint,
	 RealmID: "some company account ID"'
 }

 // Make a request!
 var companyInfo, err = qb.FetchCompanyInfo()
*/
package quickbooks

import (
	"encoding/json"
	"net/http"
	"net/url"
)

// Client is your handle to the QuickBooks API.
type Client struct {
	// Get this from oauth2.NewClient().
	Client *http.Client
	// Set to ProductionEndpoint or SandboxEndpoint.
	Endpoint EndpointURL
	// The set of quickbooks APIs
	discoveryAPI *DiscoveryAPI
	// The client ID
	clientId string
	// The client Secret
	clientSecret string
	// The account ID you're connecting to.
	RealmID string
}

func NewQuickbooksClient(clientId string, clientSecret string, realmID string, isProduction bool, token *BearerToken) (c *Client, err error) {
	var client Client
	client.clientId = clientId
	client.clientSecret = clientSecret
	client.RealmID = realmID
	if isProduction {
		client.Endpoint = ProductionEndpoint
		client.discoveryAPI = CallDiscoveryAPI(DiscoveryProductionEndpoint)
	} else {
		client.Endpoint = SandboxEndpoint
		client.discoveryAPI = CallDiscoveryAPI(DiscoverySandboxEndpoint)
	}
	if token != nil {
		client.Client = getHttpClient(token)
	}
	return &client, nil
}

// FetchCompanyInfo returns the QuickBooks CompanyInfo object. This is a good
// test to check whether you're connected.
func (c *Client) FetchCompanyInfo() (*CompanyInfo, error) {
	var u, err = url.Parse(string(c.Endpoint))
	if err != nil {
		return nil, err
	}
	u.Path = "/v3/company/" + c.RealmID + "/companyinfo/" + c.RealmID
	var v = url.Values{}
	v.Add("minorversion", minorVersion)
	u.RawQuery = v.Encode()
	var req *http.Request
	req, err = http.NewRequest("GET", u.String(), nil)
	if err != nil {
		return nil, err
	}
	req.Header.Add("Accept", "application/json")
	var res *http.Response
	res, err = c.Client.Do(req)
	if err != nil {
		return nil, err
	}
	defer res.Body.Close()

	if res.StatusCode != http.StatusOK {
		return nil, parseFailure(res)
	}

	var r struct {
		CompanyInfo CompanyInfo
		Time        Date
	}
	err = json.NewDecoder(res.Body).Decode(&r)
	return &r.CompanyInfo, err
}

// query makes the specified QBO `query` and unmarshals the result into `out`
func (c *Client) query(query string, out interface{}) error {
	var u, err = url.Parse(string(c.Endpoint))
	if err != nil {
		return err
	}
	u.Path = "/v3/company/" + c.RealmID + "/query"

	var v = url.Values{}
	v.Add("minorversion", minorVersion)
	v.Add("query", query)
	u.RawQuery = v.Encode()
	var req *http.Request
	req, err = http.NewRequest("GET", u.String(), nil)
	if err != nil {
		return err
	}
	req.Header.Add("Accept", "application/json")
	var res *http.Response
	res, err = c.Client.Do(req)
	if err != nil {
		return err
	}
	defer res.Body.Close()

	if res.StatusCode != http.StatusOK {
		return parseFailure(res)
	}

	return json.NewDecoder(res.Body).Decode(out)
}