We have developed our first Bitcoin application that went into production early this year and if you are following the Bitcoin ecosystem you might have heard of it: BitPesa is a remittance product based on Bitcoin for Kenyan diaspora.That means people can send money to there relatives in Kenya using Bitcoin.Because of the digital nature of Bitcoin it is perfect for cross-border transactions that are slow and expensive with existing payment solution.Read more about BitPesa for example here on CoinDesk In this post I want to give you a brief introduction on how to write applications that integrate with the Bitcoin network and look into different options.Like for traditional payment methods there are Payment Service Providers (PSP) for Bitcoin.These companies make it super easy for you to accept Bitcoin payments.You basically just add a little snippet to your website and you are good to go.For companies that do not want to hold Bitcoins or want to instantly exchange parts of it to fiat currency these service provides settle your account in your currency.

That means you can request your amount in fiat currency, the customer pays in Bitcoin and the service provider transfers fiat currency to your traditional bank account.There are several companies out there that you can use.Some big players and some smaller ones that often are specialised on local markets: The second type of services provide try to make Bitcoin network more accessible for developers.They focus on providing a secure Bitcoin infrastructure that the developers do not need to care about when integrating Bitcoin features.Restful HTTP APIs are provided to access data like addresses, blocks, transaction, etc. Besides using a hosted service there are also tools like insight.is or toshi.io that provide similar services but self hosted.They sit behind a full bitcoin core installation and expose a similar HTTP interface to built upon.And then you of course can directly integrate with the Bitcoin network.Here you can either call the RPC interface of the bitcoin core daemon or fully integrate Bitcoin into your application for example using the bitcoinj library.

This means you manually handle the Bitcoin keys and transactions in your application and you deal with your wallet.For sure this allows the most exciting application to be built and I highly recommend looking into the bitcoinj library.It makes working with the network pretty easy.The upcoming v0.12 release will also support hirarchicaly deterministic wallets that will allow easier backups and more security.I believe services and tools that are providing an HTTP API to the Blockchain are great tools to integrate blockchain features into applications without worrying about running the infrastructure to connect to the Bitcoin network.However most innovative application will be possible with deeper bitcoin integration.The existing tools make it easy to exactly do that and you should take a closer look to the bitcoin core implementation and the libraries mentioned above.We are currently mainly using the bitcoinj library with great success.I hope this gives you some overview of how you can build apps for the Bitcoin ecosystem.

Let us know you have questions or need help.CodeWeb DevelopmentAdding Bitcoin Payment Processing to Your WebsiteEnvato Market has a range of items for sale to help get you started.Bitcoin Payment Gateway API The BitPay bitcoin payment gateway is the most versatile, easy-to-use bitcoin API available.tasa de cambio bitcoin a dolarThe API is based on JSON and includes command line utilities that provide an easy-to-use client interface.ethereum initial offeringAPI Documentation How it Works Submit a payment request in 150+ currencies Display payment instructions on your website Receive push notifications with status updates Receive next-day settlement to bank accounts in 32 countries Plugins and Libraries Shopping Cart Plugins Sample Code Libraries PHPnodejs Supported Bitcoin Payment Methods Click-to-Pay URI   Compatibility Scan-to-Pay QR code Copy/paste payment methods Embedded Bitcoin Invoice BitPay allows you to embed the invoice on your website, so the shopper never has to leave your site during the checkout process.ethereum python

When you create an invoice with a POST request to BitPay, BitPay returns the "url" field, which is the URL at which this invoice can be viewed.To display the embedded invoice on your page, append the code &view=iframe to the invoice URL and display this URL as the source in an iframe.bitcoin 500ghThe embedded invoice will automatically update when payments have been received.buy litecoin with interacIn addition to the server IPN sent to your notificationURL, the iframe will send a POST message to the parent window that the status has changed.why did bitcoin spike in aprilIf your website has a dark background theme, append the code &theme=dark to the invoice URL.bitcoin mining thailand

Note that the iframe background color is transparent.This documentation applies to Nodemailer version v2.7.x Community version These docs apply to the unmaintained versions of Nodemailer v2 and older. homepage Nodemailer supports: Node.js 0.10+, no ES6 shenanigans used that would break your production app Unicode to use any characters, including full emoji support ?litecoin gpu performanceWindows – you can install it with npm on Windows just like any other module, there are no compiled dependencies.ethereum pool mining 2017Use it from Azure or from your Windows box hassle free.HTML content as well as plain text alternative Attachments (including attachment streaming for sending larger files) Embedded images in HTML Secure e-mail delivery using SSL/STARTTLS Different transport methods in addition to the built-in SMTP support Custom Plugin support for manipulating messages (add DKIM signatures, use markdown content instead of HTML etc.)

Sane XOAUTH2 login with automatic access token generation (and feedback about the updated tokens) Simple built-in templating and external template renderers through node-email-templates (optional) Proxies for SMTP connections (SOCKS, HTTP and custom connections) Support Nodemailer development If you want to support with Bitcoins, then my wallet address is 15Z8ADxhssKUiwP3jbbqJwA21744KMCfTM TL;DR Usage Example This is a complete example to send an e-mail with plaintext and HTML body var nodemailer = require('nodemailer'); // create reusable transporter object using the default SMTP transport :[email protected]'); // setup e-mail data with unicode symbols var mailOptions = { from: '"Fred Foo ?"<[email protected]>', // sender address to: [email protected], [email protected]', // list of receivers subject: 'Hello ✔', // Subject line text: 'Hello world ?', // plaintext body html: 'Hello world ?' // html body }; // send mail with defined transport object transporter.sendMail(mailOptions, function(error, info){ if(error){ return console.log(error); } console.log('Message sent: ' + info.response); }); Using Gmail might not work out of the box.

See instructions for setting up Gmail SMTP here.Setting up Install with npm npm install [email protected] To send e-mails you need a transporter object var transporter = nodemailer.createTransport(transport[, defaults]) Where transporter is going to be an object that is able to send mail transport is the transport configuration object, connection url or a transport plugin instance defaults is an object that defines default values for mail options You have to create the transporter object only once.If you already have a transporter object you can use it to send mail as much as you like.Send using SMTP See the details about setting up a SMTP based transporter here.Send using a transport plugin See the details about setting up a plugin based transporter here.If the transport plugin follows common conventions, then you can also load it dynamically with the transport option.This way you would not have to load the transport plugin in your code (you do need to install the transport plugin before you can use it), you only need to modify the configuration data accordingly.

var nodemailer = require('nodemailer'); var transporter = nodemailer.createTransport({ transport: 'ses', // loads nodemailer-ses-transport accessKeyId: 'AWSACCESSKEY', secretAccessKey: 'AWS/Secret/key' }); Sending mail Once you have a transporter object you can send mail with it: transporter.sendMail(data[, callback]) Where data defines the mail content (see e-mail message fields below) callback is an optional callback function to run once the message is delivered or it failed err is the error object if message failed info includes the result, the exact format depends on the transport mechanism used info.messageId most transports should return the final Message-Id value used with this property info.envelope includes the envelope object for the message info.accepted is an array returned by SMTP transports (includes recipient addresses that were accepted by the server) info.rejected is an array returned by SMTP transports (includes recipient addresses that were rejected by the server) info.pending is an array returned by Direct SMTP transport.

Includes recipient addresses that were temporarily rejected together with the server response response is a string returned by SMTP transports and includes the last SMTP response from the server If the message includes several recipients then the message is considered sent if at least one recipient is accepted If callback argument is not set then the method returns a Promise object.Nodemailer itself does not use Promises internally but it wraps the return into a Promise for convenience.E-mail message fields The following are the possible fields of an e-mail message: Commmon fields from – The e-mail address of the sender.All e-mail addresses can be plain [email protected]' or formatted '"Sender Name" <[email protected]>', see Address formatting for details to – Comma separated list or an array of recipients e-mail addresses that will appear on the To: field cc – Comma separated list or an array of recipients e-mail addresses that will appear on the Cc: field bcc – Comma separated list or an array of recipients e-mail addresses that will appear on the Bcc: field subject – The subject of the e-mail text – The plaintext version of the message as an Unicode string, Buffer, Stream or an attachment-like object ({path: '/var/data/...'})

html – The HTML version of the message as an Unicode string, Buffer, Stream or an attachment-like object ({path: 'http://...'})attachments – An array of attachment objects (see Using attachments for details).Attachments can be used for embedding images as well.A large majority of e-mails sent look a lot like this, using only a few basic fields: var mailData = { from: [email protected]', to: [email protected]', subject: 'Message title', text: 'Plaintext version of the message', html: 'HTML version of the message' }; NB!All text fields (e-mail addresses, plaintext body, html body, attachment filenames) use UTF-8 as the encoding.Attachments are streamed as binary.More advanced fields sender – An e-mail address that will appear on the Sender: field (always prefer from if you’re not sure which one to use) replyTo – An e-mail address that will appear on the Reply-To: field inReplyTo – The message-id this message is replying to references – Message-id list (an array or space separated string) watchHtml – Apple Watch specific HTML version of the message icalEvent – iCalendar event to use as an alternative.

Same usage as with text or html.Additionally you could set method property (defaults to 'PUBLISH').See an example here priority – Sets message importance headers, either 'high', 'normal' (default) or 'low'.headers – An object or array of additional header fields (e.g.{“X-Key-Name”: “key value”} or [{key: “X-Key-Name”, value: “val1”}, {key: “X-Key-Name”, value: “val2”}]).Read more about custom headers here alternatives – An array of alternative text contents (in addition to text and html parts) (see Using alternative content for details) envelope – optional SMTP envelope, if auto generated envelope is not suitable (see SMTP envelope for details) messageId – optional Message-Id value, random value will be generated if not set date – optional Date value, current UTC string will be used if not set encoding – identifies encoding for text/html strings (defaults to ‘utf-8’, other values are ‘hex’ and ‘base64’) raw – existing MIME message to use instead of generating a new one.

If this value is set then you should also set the envelope object (if required) as the provided raw message is not parsed.The value could be a string, a buffer, a stream or an attachment-like object.textEncoding – force content-transfer-encoding for text values (either quoted-printable or base64).By default the best option is detected (for lots of ascii use quoted-printable, otherwise base64) list – helper for setting List-* headers (see more here) disableFileAccess if true, then does not allow to use files as content.Use it when you want to use JSON data from untrusted source as the email.If an attachment or message node tries to fetch something from a file the sending returns an error.If this field is also set in the transport options, then the value in mail data is ignored disableUrlAccess if true, then does not allow to use Urls as content.If this field is also set in the transport options, then the value in mail data is ignored var mailData = { ..., headers: { 'My-Custom-Header': 'header value' }, date: new Date('2000-01-01 00:00:00') }; NB!

When using readable streams as any kind of content and sending fails then Nodemailer does not abort the already opened but not yet finished stream automatically, you need to do this yourself var htmlstream = fs.createReadStream('content.html'); transport.sendMail({html: htmlstream}, function(err){ if(err){ // check if htmlstream is still open and close it to clean up } }); Available Plugins In addition to built-in e-mail fields you can extend these by using plugins.nodemailer-markdown to use markdown for the content nodemailer-dkim to sign messages with DKIM nodemailer-html-to-text to auto generate plaintext content from html nodemailer-express-handlebars to auto generate html emails from handlebars/mustache templates nodemailer-plugin-inline-base64 to convert base64 images to attachments nodemailer-hashcash to generate hashcash headers add yours (see plugin api documentation here) Implementing plugins and transports See plugin implementation documentation here.