openalpr
Version:
Open ALPR JavaScript SDK for Multei
220 lines (174 loc) • 7.18 kB
JavaScript
(function (global, factory) {
typeof exports === 'object' && typeof module !== 'undefined' ? factory(require('debug'), require('axios')) :
typeof define === 'function' && define.amd ? define(['debug', 'axios'], factory) :
(global = global || self, factory(global.debug, global.axios));
}(this, (function (Debug, axios) { 'use strict';
Debug = Debug && Object.prototype.hasOwnProperty.call(Debug, 'default') ? Debug['default'] : Debug;
axios = axios && Object.prototype.hasOwnProperty.call(axios, 'default') ? axios['default'] : axios;
const debug = Debug('openalpr:removeBase64Prefix');
function removeBase64Prefix(data) {
if(typeof data !== "string") {
throw new Error(`Can not recognize base64 data. This is not a valid base64 string. Got ${data}`)
}
if(data === '') {
throw new Error('Can not recognize base64 data from an empty string.')
}
debug('Splitting base64 prefix from image data...');
const dataSplit = data.split(',');
debug('Checking if split data contains prefix...');
if(dataSplit.length > 1) {
debug('Split data contains prefix: %o', dataSplit[0]);
return dataSplit[1];
}
debug('Returning original string (it does not have base64 prefix)');
return dataSplit[0];
}
const debug$1 = Debug('openalpr:handler:error');
function handleErrorResponse(error) {
debug$1('Handling error response...');
if(typeof error.response !== "undefined") {
debug$1('Request made, server responded with error status code');
/*
* The request was made and the server responded with a
* status code that falls out of the range of 2xx
*/
const { data, status, headers } = error.response;
return { data, status, headers }
}
if(typeof error.request !== "undefined") {
debug$1('Request made but no response received');
/*
* The request was made but no response was received, `error.request`
* is an instance of XMLHttpRequest in the browser and an instance
* of http.ClientRequest in Node.js
*/
return error.request
}
if(typeof error.message !== "undefined") {
debug$1('Request not made. Found error %o', error.message);
// Something happened in setting up the request and triggered an Error
return error.message
}
debug$1('Unknown error found: %o', error);
return error;
}
const debug$2 = Debug('openalpr:handler:response');
function handleResponse(response) {
debug$2('Returning response data...');
return response.data
}
const debug$3 = Debug('openalpr:openalpr');
/**
* Create a new instance of OpenALPR
*
* @param instanceConfig
* @constructor
*/
function OpenALPR(instanceConfig) {
debug$3('Constructing OpenALPR instance...');
this.defaults = instanceConfig;
}
/**
* Dispatch a recognition
*
* @param {Object} config The config specific for this request (merged with this.defaults)
* @return {Promise<*>}
*/
OpenALPR.prototype.recognize = async function recognize(data, config = {}) {
if(typeof data === 'undefined') {
throw new Error('Image base64 data is missing. Please check recognize() function call')
}
if(data === '' || data === null) {
throw new Error('Image data is empty or null. Please check recognize() function call')
}
debug$3('Setting config...');
config = {...this.defaults, ...config};
debug$3('Creating axios instance with OpenALPR API data...');
const instance = axios.create({baseURL: 'https://api.openalpr.com/v2'});
debug$3('Building request URL...');
const url = `/recognize_bytes?recognize_vehicle=1&country=br&secret_key=${config["secretKey"]}`;
try {
debug$3('Removing base64 prefix (if needed)...');
data = removeBase64Prefix(data);
if(typeof data === "undefined") {
throw new Error("Cannot make request to API. Image data is undefined after base64 prefix removal")
}
debug$3('Making request to OpenALPR with raw data...');
const response = await instance.post(url, data, { headers: {'content-type': 'raw'} });
debug$3('Calling response handler...');
return handleResponse(response)
}
catch (error) {
debug$3('Calling error handler...');
throw handleErrorResponse(error)
}
};
const defaults = {
secretKey: null
};
const debug$4 = Debug('openalpr:main');
/**
* Create an instance of OpenALPR
*
* @param {Object} defaultConfig The default config for the instance
* @return {OpenALPR} A new instance of OpenALPR
*/
function createInstance(instanceConfig = defaults) {
debug$4('Creating an instance...');
return new OpenALPR(instanceConfig);
}
/**
* Create the default instance to be exported
*/
const openALPR = createInstance(defaults);
/**
* Expose OpenALPR class to allow class inheritance
*
* @type {OpenALPR}
*/
openALPR.OpenALPR = OpenALPR;
/**
* Factory for creating new instances
*
* @param {Object} instanceConfig
* @return {OpenALPR}
*/
openALPR.create = function create(instanceConfig) {
debug$4('Returning the new instance...');
return createInstance({...defaults, ...instanceConfig})
};
const debug$5 = Debug('openalpr:express-middleware');
module.exports = (fileIndex) => async (req, res, next) => {
debug$5('Entered OpenALPR middleware...');
if(typeof process.env.OPENALPR_SECRET_KEY === 'undefined') {
throw new Error('Can not call OpenALPR API. Secret key is missing.')
}
const openALPR$1 = openALPR.create({
secretKey: process.env.OPENALPR_SECRET_KEY
});
const handleRecognition = result => {
debug$5('Recognition result: %o', result);
if(result.status === 400) {
throw new Error('Can not recognize data from image. OpenALPR returned 400')
}
else if(result.results.length == 0) {
throw new Error('There is no car plate on image')
}
debug$5('Success recognizing vehicle!');
req.recognitionData = req.recognitionData || {};
req.recognitionData[fileIndex] = result;
};
try {
const encoded = req.files[fileIndex][0].buffer.toString('base64');
debug$5('Generating encoded base64 file');
debug$5('Starting vehicle recognition');
const result = await openALPR$1.recognize(encoded);
debug$5('Starting to handle recognition...');
handleRecognition(result);
next();
} catch(err) {
debug$5('Vehicle recognition failed');
next(err);
}
};
})));