agecem-org/api/api.go

package api

import (
	"bytes"
	"encoding/json"
	"errors"
	"fmt"
	"io"
	"io/ioutil"
	"mime/multipart"
	"net/http"
	"net/url"

	"git.agecem.com/agecem/agecem-org/config"
	"github.com/spf13/viper"
)

type API struct {
	Protocol string
	Host     string
	Port     int
	Opts     APIOptions
}

type APIOptions struct {
	KeyAuth   bool
	Key       string
	BasicAuth bool
	Username  string
	Password  string
}

type UploadDocumentResponse struct {
	Info    UploadDocumentResponseInfo `json:"info"`
	Message string                     `json:"message"`
}

type UploadDocumentResponseInfo struct {
	Bucket string  `json:"bucket"`
	Object string  `json:"key"`
	Size   float64 `json:"size"`
}

// NewApiClientFromViper returns a pointer to a new API object,
// provided the configuration options are managed by
// https://git.agecem.com/agecem/agecem-org/config
func NewApiClientFromViper() (*API, error) {
	var config config.Config

	if err := viper.Unmarshal(&config); err != nil {
		return nil, err
	}

	api, err := New(config.Server.Api.Protocol, config.Server.Api.Host, config.Server.Api.Port, APIOptions{
		KeyAuth: config.Server.Api.Auth,
		Key:     config.Server.Api.Key,
	})
	if err != nil {
		return api, err
	}

	return api, nil
}

func New(protocol, host string, port int, opts APIOptions) (*API, error) {
	api := API{
		Protocol: protocol,
		Host:     host,
		Port:     port,
		Opts:     opts,
	}

	return &api, nil
}

// Call returns a []byte representing a response body.
// Can be used for GET or DELETE methods
func (a *API) Call(method, route string) ([]byte, error) {
	endpoint := fmt.Sprintf("%s://%s:%d",
		a.Protocol,
		a.Host,
		a.Port,
	)
	prerequest := fmt.Sprintf("%s%s", endpoint, route)
	request, err := url.QueryUnescape(prerequest)
	if err != nil {
		return nil, err
	}

	switch method {
	case http.MethodGet:
		// Create client
		client := &http.Client{}

		// Create request
		request, err := http.NewRequest(http.MethodGet, request, nil)
		if err != nil {
			return nil, err
		}

		if a.Opts.KeyAuth {
			request.Header.Add("Authorization", fmt.Sprintf("Bearer %s", a.Opts.Key))
		}

		// Fetch Request
		response, err := client.Do(request)
		if err != nil {
			return nil, err
		}

		defer response.Body.Close()

		body, err := ioutil.ReadAll(response.Body)
		if err != nil {
			return nil, err
		}

		return body, nil
	case http.MethodDelete:
		// Create client
		client := &http.Client{}

		// Create request
		req, err := http.NewRequest(http.MethodDelete, request, nil)
		if err != nil {
			return nil, err
		}

		if a.Opts.KeyAuth {
			req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", a.Opts.Key))
		}

		// Fetch Request
		resp, err := client.Do(req)
		if err != nil {
			return nil, err
		}
		defer resp.Body.Close()

		// Read Response Body
		respBody, err := ioutil.ReadAll(resp.Body)
		if err != nil {
			return nil, err
		}
		return respBody, nil
	}

	//return nil, errors.New(fmt.Sprintf("method must be 'GET' or 'DELETE', got '%s'", method))
	return nil, errors.New(fmt.Sprintf("method must be 'GET' or 'DELETE', got '%s'", method))
}

func (a *API) UploadDocument(bucket string, file_header *multipart.FileHeader) (UploadDocumentResponse, error) {
	var response UploadDocumentResponse
	endpoint := fmt.Sprintf("%s://%s:%d",
		a.Protocol,
		a.Host,
		a.Port,
	)

	current_url := fmt.Sprintf("%s/v1/bucket/%s", endpoint, bucket)

	// Create a new multipart writer
	body := &bytes.Buffer{}
	writer := multipart.NewWriter(body)

	// Add the file to the request
	file, err := file_header.Open()
	if err != nil {
		return response, fmt.Errorf("UploadDocument#file_header.Open: %s", err)
	}
	defer file.Close()

	filename_processed, err := url.QueryUnescape(file_header.Filename)
	if err != nil {
		return response, fmt.Errorf("UploadDocument#url.QueryUnescape: %s", err)
	}

	part, err := writer.CreateFormFile("document", filename_processed)
	if err != nil {
		return response, fmt.Errorf("UploadDocument#writer.CreateFormFile: %s", err)
	}

	_, err = io.Copy(part, file)
	if err != nil {
		return response, fmt.Errorf("UploadDocument#io.Copy: %s", err)
	}

	err = writer.Close()
	if err != nil {
		return response, fmt.Errorf("UploadDocument#writer.Close: %s", err)
	}

	// Create a new HTTP request with the multipart body
	req, err := http.NewRequest(http.MethodPost, current_url, body)
	if err != nil {
		return response, fmt.Errorf("UploadDocument#http.NewRequest: %s", err)
	}

	req.Header.Set("Content-Type", writer.FormDataContentType())

	if a.Opts.KeyAuth {
		req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", a.Opts.Key))
	}

	// Send the HTTP request
	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		return response, fmt.Errorf("UploadDocument#client.Do: %s", err)
	}
	defer resp.Body.Close()

	err = json.NewDecoder(resp.Body).Decode(&response)
	return response, err
}

// CallWithData takes data and returns a string representing a response body.
// Can be used for POST or PUT methods
func (a *API) CallWithData(method, route string, data []byte) (string, error) {
	endpoint := fmt.Sprintf("%s://%s:%d",
		a.Protocol,
		a.Host,
		a.Port,
	)
	request := fmt.Sprintf("%s%s", endpoint, route)

	switch method {
	case http.MethodPost:
		// initialize http client
		client := &http.Client{}

		// set the HTTP method, url, and request body
		req, err := http.NewRequest(http.MethodPost, request, bytes.NewBuffer(data))
		if err != nil {
			return "", err
		}

		if a.Opts.KeyAuth {
			req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", a.Opts.Key))
		}

		// set the request header Content-Type for json
		req.Header.Set("Content-Type", "application/json; charset=utf-8")
		resp, err := client.Do(req)
		if err != nil {
			return "", err
		}

		var res map[string]interface{}

		json.NewDecoder(resp.Body).Decode(&res)
		return fmt.Sprintf("%s\n", res["message"]), nil
		/*
			case http.MethodPut:
				// initialize http client
				client := &http.Client{}

				// set the HTTP method, url, and request body
				req, err := http.NewRequest(http.MethodPut, request, bytes.NewBuffer(data))
				if err != nil {
					return "", err
				}

				if a.Opts.KeyAuth {
					req.Header.Add("Authorization", fmt.Sprintf("Bearer %s", a.Opts.Key))
				}

				// set the request header Content-Type for json
				//req.Header.Set("Content-Type", "application/json; charset=utf-8")
				resp, err := client.Do(req)
				if err != nil {
					return "", err
				}

				var res map[string]interface{}

				json.NewDecoder(resp.Body).Decode(&res)
				return fmt.Sprintf("%s\n", res["message"]), nil
		*/
	}

	//return "", errors.New(fmt.Sprintf("method must be 'POST' or 'PUT', got '%s'", method))
	return "", errors.New(fmt.Sprintf("method must be 'POST', got '%s'", method))
}