book

Twisted Network Programming Essentials, 2nd Edition

by Abe Fettig, Jessica McKellar

March 2013

Beginner

191 pages

4h 9m

English

O'Reilly Media, Inc.

Read now

Unlock full access

Why Use Twisted?What This Book CoversConventions Used in This BookWhat You’ll NeedChanges Since the Previous EditionUsing Code ExamplesSafari® Books OnlineHow to Contact UsAcknowledgments
Installing TwistedInstallation on LinuxMore package options and optional dependenciesInstallation on WindowsOptional dependenciesAdding Twisted utilities to your PATHInstallation on OS XOptional dependenciesInstalling from SourceRequired DependenciesInstalling a C compilerInstalling zope.interfaceInstalling Twisted from a Release TarballInstalling Twisted from a Source CheckoutInstalling Optional Dependencies from SourceTesting Your InstallationUsing the Twisted DocumentationAPI DocumentationSubproject DocumentationFinding Answers to Your QuestionsMailing ListsIRC ChannelsStack OverflowTwisted Blogs
A TCP Echo Server and ClientEvent-Driven ProgrammingThe ReactorTransportsProtocolsProtocol FactoriesDecoupling Transports and ProtocolsA TCP Quote Server and ClientProtocol State MachinesMore Practice and Next Steps
What Deferreds Do and Don’t DoThe Structure of a Deferred ObjectCallback Chains and Using Deferreds in the ReactorPractice: What Do These Deferred Chains Do?Exercise 1Exercise 2Exercise 3Exercise 4Exercise 5Exercise 6The Truth About addCallbacksExercise 7Exercise 8Key Facts About DeferredsSummary of the Deferred APIMore Practice and Next Steps
Responding to HTTP Requests: A Low-Level ReviewThe Structure of an HTTP RequestParsing HTTP RequestsHandling GET RequestsServing Static ContentStatic URL dispatchServing Dynamic ContentDynamic DispatchCreating resources that are both renderable and have childrenRedirectsHandling POST RequestsA Minimal POST ExampleAsynchronous ResponsesMore Practice and Next Steps
Basic HTTP Resource RetrievalPrinting a Web ResourceDownloading a Web ResourceAgentRequesting Resources with AgentRetrieving Response MetadataPOSTing Data with AgentMore Practice and Next Steps
The Twisted Application InfrastructureServicesApplicationsTAC FilestwistdPluginsMore twistd ExamplesMore Practice and Next StepsSuggested Exercises

Basic In-Application Loggingtwistd LoggingCustom LoggersKey Facts and Caveats About Logging
Nonblocking Database QueriesMore Practice and Next Steps
The Components of Twisted CredTwisted Cred: An ExampleCredentials CheckersAuthentication in Twisted ApplicationsMore Practice and Next Steps
ThreadsSubprocessesRunning a Subprocess and Getting the ResultCustom Process ProtocolsMore Practice and Next Steps
Writing and Running Twisted Unit Tests with TrialTesting ProtocolsTests and the ReactorTesting DeferredsTesting the Passage of TimeMore Practice and Next Steps
IRC ClientsIRC ServersMore Practice and Next Steps
SMTP Clients and ServersThe SMTP ProtocolSending Emails Using SMTPSMTP ServersStoring MailIMAP Clients and ServersIMAP ServersIMAP ClientsPOP3 Clients and ServersPOP3 ServersMore Practice and Next Steps
SSH ServersA Basic SSH ServerUsing Public Keys for AuthenticationProviding an Administrative Python ShellRunning Commands on a Remote ServerSSH ClientsMore Practice and Next Steps
Contributing to Twisted

Content preview from Twisted Network Programming Essentials, 2nd Edition

Chapter 13. Twisted Mail

Twisted comes with support for building clients and servers for the three big email protocols in common use today: SMTP, IMAP, and POP3.

Each of these protocols has a lot of components and is meticulously documented in multiple RFCs; covering the ins and outs of mail servers and clients could be a book in and of itself. The goal for this chapter is instead to give you broad-strokes familiarity with the protocols and the APIs Twisted provides for them, through some simple but runnable and tinker-friendly examples. By the end, you should have a good idea of what you’d need to do to build arbitrary email applications in Twisted.

To describe in brief the main uses for each of these protocols:

SMTP: SMTP, the Simple Mail Transfer Protocol, is for sending mail; when you send an e-mail from the Gmail web interface, your Thunderbird desktop app, or the mail app on your smartphone, that message is probably getting sent over SMTP.
IMAP: IMAP, the Internet Message Access Protocol, is used for remote access, storage, and management of email messages. Remote management makes it easy to read and send mail from more than one place. The fact that you see the same messages on your phone, web interface, and desktop app is probably because your email provider is using IMAP for remote management.
POP3: POP3, the Post Office Protocol version 3, is an older and simpler protocol than IMAP, but still prevalent. POP3 does one thing, and does it well: it allows a user to log into a mail server ...