Developing Mobile Apps with Exchange Web Services - PowerPoint Presentation

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Developing Mobile Apps with Exchange Web Services

Paul Robichauxpaul@robichaux.net

OUC-B304Slide3

Mobile devices are important

They are ubiquitous.

They represent both a huge opportunity and a huge risk in the enterprise.

BYOD: Bring Your Own Disaster

Building custom apps for mobile use…

provides a high-value path for integrating mobile access into your core business operations.

Supplements desktop and web access to your line of business applicationsSlide4

Mobile platforms

There

are many popular platforms but 3 of them

are the clear leaders

.

Google Android: Java-based with sandboxed

Dalvik

VM

Windows Phone: XAML/CSS or native .NET Framework code

Apple

iOS

: Objective-C

Each platform has its boosters and detractors

Each platform can host HTML5 “apps”

But native apps still offer

far more flexibility and capability: access to sensors, persistent rich storage, offline/disconnected operation…Slide5

Exchange as a development platform

Exchange ActiveSync has won the device sync war

Robust, mature, incredibly broad device support

Even major competitors license it from Microsoft

Exchange Web Services provides rich access to data items in Exchange store + services

Data: calendar

and mail items, metadata (free/busy, OOF), user photos, and more

Provisioning: manage rules, search data, offer impersonation, and moreSlide6

What this session is

Coverage of using Exchange technologies to build apps for Apple

iOS

devices

Using Exchange ActiveSync services

Using Exchange Web Services features

Using Apple’s native development tools

Practical look at using

iOS

with these services

Unlike Windows Phone, no OS-level support for most of what we want to doSlide7

What this session is NOT

Discussion of using Exchange technologies to build apps for other mobile operating systems

Android: no thank you

Windows Phone: see the excellent developer-track sessions here at

TechEd

BlackBerry

Other nascent or moribund platforms

A complete guide to

iOS

developmentSlide8

What about the Managed EWS API?

Extremely robust, powerful set of APIs for accessing EWS from managed code

Managed code support on

iOS

requires third-party tools

Trying to integrate .NET managed code and

Obj

-C can be tricky

Limited support resources in the community

Great for desktop Windows & Windows Phone

But not a topic of discussion for us todaySlide9

The basic pattern

Pre-create XML blobs that contain the data we want to send

Most efficiently done by

building static strings and subbing in parameters

at runtime

Contents defined by EWS schema as published on TechNet

Experimentally verified by using Fiddler to monitor a WP8 device while it syncs

Send them to the server as HTTP POST

AsiHTTPConnection

helper class… not the latest but still works well

Parse the resulting XML

GDataXMLNode

provides

best balance of speed and simplicity of implementationSlide10

Using the basic pattern

Autodiscover: find the server we want to talk to

This will get us the URLs of all the EWS service endpoints

Services: do whatever it is our app does

Consume services exposed as URLs from the Autodiscover manifest

This might include UM, calendar/contact/mail access, modifying inbox rules…Slide11

Using AutodiscoverSlide12

Using Exchange ActiveSync

Protocol

specification offered by Microsoft for how to talk to Exchange from mobile devices

Fully documented online

Mostly of interest when you’re developing an entire client

Except for

Autodiscover, which everyone needsSlide13

Autodiscover

Goal: ask user for e-mail address and password, then find everything else we need without user action

Works differently for domain-joined and non-domain-joined clients

We will ignore domain-joined Autodiscover

So no SCPs, Kerberos, or Active Directory interaction

from our

iOS

appsSlide14

Autodiscover work flow

Collect user credentials

This is easy

Query well-known Autodiscover service points, in order

This is also easy if you read the Autodiscover

spec

At each step

we will either get a valid response, an error, or an HTTP redirect

Errors may include authentication requestsSlide15

Autodiscover in depth

Try HTTPS POST to

domain.com

/

autodiscover

/

autodiscover.xml

autodiscover.

domain.com

/

autodiscover

/

autodiscover

If those requests fail, then try

Unauthenticated HTTP GET to

autodiscover.

domain.com

/

autodiscover

/

autodiscover

DNS SRV query for _

autodiscover

._

tcp.

domain

Slide16

Autodiscover responses

Server may respond

with

302 redirect

AutoD

manifest

AutoD

error

response

403 error

404 error

HTTP

error if you wrote bad request

code

Exchange 2007/2010 may also emit 451 redirect

Most devices don’t handle it properly, which is why Exchange 2013 doesn’tSlide17

Autodiscover resources

The Exchange 2007 Exchange

Web Services book is pretty good

http://

blogs.msdn.com

/b/

exchangedev

/archive/2011/07/08/

autodiscover

-for-exchange-

activesync

-

developers.aspxSlide18

Autodiscover sample

if ([autoD

connectToServer

]) { self.serverURL

= [

autoD

serverURL

];

[

self.oof

getCurrentOOFState

];

}

…it takes hard work to look this good!Slide19

Example: OOF management with EWSSlide20

Demo

ExOOF: managing OOF properties with EWSSlide21

Exploring the AutoD

class

The only way to see everything we want to see is in

Xcode

…Slide22

How’d we get the OOF state?

ASIHTTPRequest

*

oofRequest = [

ASIHTTPRequest

requestWithURL

:

appDelegate.serverURL

]

;

ExUser

*who =

appDelegate.theUser

;

[

oofRequest

setUsername:who.userName

];

[

oofRequest

setPassword

:

who.userPassword

];

[

oofRequest

addRequestHeader

:@"Content-Type"

value

:[

NSString

stringWithFormat

:@"text/xml

;

charset

=utf-8"]];

[

oofRequest

appendPostData

:[[self request

]

dataUsingEncoding:NSUTF8StringEncoding]];

[

oofRequest

startSynchronous

]

;Slide23

What the server returns

OOF data is an XML document based on a defined EWS schema

So all we need to do is parse itSlide24

The rest of getCurrentOOFState

Let’s take a look and see what happens here…

Retrieve data from URL result

Ask

GDataXMLDocument

to parse it

Use

nodesForXPath

: to pick out the parts we care about

Tie the results into the UISlide25

Setting the OOF state

…basically a giant printf

()

We have values associated with controls/fields in the GUI

Retrieve those values, format them per the EWS OOF schema, and POST the data backSlide26

Example: Calendar managementSlide27

Calendaring

Mobile devices include calendar apps…

…but suppose you have a LOB app that you want to use the Exchange

calendar

Scheduling appointments

Reserving

resourcesSlide28

Demo

ExCal: viewing and managing calendar itemsSlide29

Getting calendar items

FindItem will retrieve items subject to the parameters you set

Base

folder: calendar, Inbox, sub folders,

etc

Start

/ end times

Item type

In this case we’re searching for calendar items

for the week of

TechEd

,

max 500Slide30

FindItem results

FindItem

gives us an XML structure containing the items of interest, if

any

May also return errors

We just iterate over them and add them to our list

viewSlide31

Our FindItem

request

<

FindItem

Traversal=\"Shallow\" xmlns

=\"

http://schemas.microsoft.com/exchange/services/2006/messages\">

<

ItemShape

><

t:BaseShape

>

IdOnly

</

t:BaseShape

>

<

t:AdditionalProperties

>

<

t:FieldURI

FieldURI

=\"

calendar:Start

\"/>

<

t:FieldURI

FieldURI

=\"

calendar:End

\"/>

<

t:FieldURI

FieldURI

=\"

item:Subject

\"/>

</

t:AdditionalProperties

>

</

ItemShape

>

<

CalendarView

MaxEntriesReturned

=\"500\"

StartDate

=\"2013-06-03T00:00:00-08:00\"

EndDate

=\"2013-06-07T00:00:00-08:00\"/>

<

ParentFolderIds

><

t:DistinguishedFolderId

Id=\"calendar\"/></

ParentFolderIds

>

</

FindItem

>Slide32

Displaying returned items

Let’s

examine

this

in

Xcode

…Slide33

Adding calendar items

EWS CreateItem

to the rescue!

CreateItem

expects a

shape

, or template

We create a basic shape and add specific properties to itSlide34

Building an item shape

Let’s

examine

this

in

Xcode

…Slide35

Nifty Exchange 2013 Things You Can DoSlide36

Use the Unified Contact Store

Unified Exchange & Lync contacts

Stored as “Lync Contacts” folder as subfolder of user’s Calendar folder

Add, remove, read items there using new UCS-specific operations

e.g.

AddNewImContactToGroup

,

GetImItemsSlide37

Work with high-resolution photos

Retrieve photos at multiple resolutions and sizes

648x648 is my favorite

Stored as FAI once user uploads & approves photo

Accessible via URL:

https

:/

/

server

/

ews/Exchange.asmx/s/GetUserPhoto?email

=

alias

&

size=

HR648x648

Accessible via EWS through new

GetUserPhoto

item (see MSDN)Slide38

Work with e-discovery & retention

Archive items

in the user’s Personal Archive

Modify, create, update discovery searches

Get / set / review retention tags and policiesSlide39

Track resources

My blog:

http://

paulrobichaux.wordpress.com

Exchange

Team Blog:

http

://blogs.technet.com/b/exchange

/

MSDN New Features in EWS

in Exchange 2013:

http://

msdn.microsoft.com

/en-us/library/exchange/jj190903(v=exchg.150).

aspx

Twitter

:

Follow

@

MSFTExchange

Follow @

PaulRobichaux

Join the conversation: use #

IAmMEC

Check

out:

Microsoft Exchange

Conference 2014:

www.iammec.com

Office 365

FastTrack

: http://fasttrack.office.com/

/

Technical Training with Ignite

: http://ignite.office.com

/Slide40

msdn

Resources for Developers

http://microsoft.com/msdn

Learning

Microsoft Certification & Training Resources

www.microsoft.com/learning

TechNet

Resources

Sessions on Demand

http://channel9.msdn.com/Events/TechEd

Resources for IT Professionals

http://microsoft.com/technet Slide41

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© 2013 Microsoft Corporation. All rights reserved. Microsoft, Windows and other product names are or may be registered trademarks and/or trademarks in the U.S. and/or other countries.

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