Hey, Scripting Guy! How Can I Use a Web Service to Find Weather for a Specific City?
Hey, Scripting Guy! I thought your script yesterday was pretty cool, but there is a problem with it. Retrieving the weather from a script is awesome; however, I need to know which cities are available. If I want to know the weather in Sydney, Australia (your example), I am all set. I’m sure you can see this coming: I do not live in Sydney and therefore the script is useless. How about displaying a list of available cities so that I can figure out how to use the script?
— NR
Hello NR,
I am listening to the Travelling Wilburys on my new Zune HD. It is an absolutely gorgeous day outside—deep blue cloudless skies and a temperature of 69 degrees Fahrenheit (20.5 degrees Celsius). I have opened all the windows in my scripting house, and I am reclining in my large leather scripting chair checking the scripting e-mail sent to scripter@microsoft.com on my Windows 7 scripting laptop. I have a fresh pot of scripting English Breakfast tea, lemon grass, and cinnamon stick. It is a perfect way to enjoy the mellow Charlotte, North Carolina, weather after the weeklong deluge gifted to the area by tropical storm Ida. NR, you are right about the practicality of knowing the weather in Sydney, Australia. Whereas I might dream of heading back to Australia, with the realities of the current budget crunch, I probably will not make it back to Australia before 2011. Therefore, I better see if I can check out the weather report for Charlotte, North Carolina.
NR, the Get-InternationalCities.ps1 script uses the globalweather Web service and the GetCitiesByCountry method to return a list of available cities. The complete Get-InternationalCities.ps1 script follows.
Get-InternationalCities.ps1
$country = “united states”
$URI = “http://www.webservicex.net/globalweather.asmx?wsdl”
$Proxy = New-WebServiceProxy -uri $URI -namespace WebServiceProxy
$countries = [xml]$proxy.GetCitiesByCountry($country)
$countries.NewDataSet.Table | Sort-Object -Property city |
Select-Object -Property city
The first thing the Get-InternationalCities.ps1 script does is assign a value for the $country variable. The value of the $country variable is used to retrieve the list of cities. This is shown here:
$country = “united states”
After the country has been set for the script, you need to assign the path to the globalweather Web Service Definition Language (WSDL) to the $URI variable. The WSDL is an XML document that describes the service offering. Because the WSDL string is a Uniform Resource Locator (URL), you can open it directly in Internet Explorer and look for methods and properties described by the WSDL. The following image illustrates this:
After you assign the path to the $URI variable, you can use the New-WebServiceProxy cmdlet to create a Web service proxy that allows you to connect and to retrieve information from the globalweather Web service. The returned object is a special webserviceproxy object that is created from the Web service that is specified in the $URI variable. The members of the WebServiceProxy.GlobalWeather object are shown here:
TypeName: WebServiceProxy.GlobalWeather
Name MemberType Definition
—- ———- ———-
Disposed Event System.EventHandler Disposed(System.Object, System.Ev…
GetCitiesByCountryCompleted Event WebServiceProxy.GetCitiesByCountryCompletedEventHandl…
GetWeatherCompleted Event WebServiceProxy.GetWeatherCompletedEventHandler GetWe…
Abort Method System.Void Abort()
BeginGetCitiesByCountry Method System.IAsyncResult BeginGetCitiesByCountry(string Co…
BeginGetWeather Method System.IAsyncResult BeginGetWeather(string CityName, …
CancelAsync Method System.Void CancelAsync(System.Object userState)
CreateObjRef Method System.Runtime.Remoting.ObjRef CreateObjRef(type requ…
Discover Method System.Void Discover()
Dispose Method System.Void Dispose()
EndGetCitiesByCountry Method string EndGetCitiesByCountry(System.IAsyncResult asyn…
EndGetWeather Method string EndGetWeather(System.IAsyncResult asyncResult)
Equals Method bool Equals(System.Object obj)
GetCitiesByCountry Method string GetCitiesByCountry(string CountryName)
GetCitiesByCountryAsync Method System.Void GetCitiesByCountryAsync(string CountryNam…
GetHashCode Method int GetHashCode()
GetLifetimeService Method System.Object GetLifetimeService()
GetType Method type GetType()
GetWeather Method string GetWeather(string CityName, string CountryName)
GetWeatherAsync Method System.Void GetWeatherAsync(string CityName, string C…
InitializeLifetimeService Method System.Object InitializeLifetimeService()
ToString Method string ToString()
AllowAutoRedirect Property System.Boolean AllowAutoRedirect {get;set;}
ClientCertificates Property System.Security.Cryptography.X509Certificates.X509Cer…
ConnectionGroupName Property System.String ConnectionGroupName {get;set;}
Container Property System.ComponentModel.IContainer Container {get;}
CookieContainer Property System.Net.CookieContainer CookieContainer {get;set;}
Credentials Property System.Net.ICredentials Credentials {get;set;}
EnableDecompression Property System.Boolean EnableDecompression {get;set;}
PreAuthenticate Property System.Boolean PreAuthenticate {get;set;}
Proxy Property System.Net.IWebProxy Proxy {get;set;}
RequestEncoding Property System.Text.Encoding RequestEncoding {get;set;}
Site Property System.ComponentModel.ISite Site {get;set;}
SoapVersion Property System.Web.Services.Protocols.SoapProtocolVersion Soa…
Timeout Property System.Int32 Timeout {get;set;}
UnsafeAuthenticatedConnectionSharing Property System.Boolean UnsafeAuthenticatedConnectionSharing {…
Url Property System.String Url {get;set;}
UseDefaultCredentials Property System.Boolean UseDefaultCredentials {get;set;}
UserAgent Property System.String UserAgent {get;set;}
The name webserviceproxy comes from the value we specified for the namespace parameter with the New-WebServiceProxy cmdlet. This is seen here:
$URI = “http://www.webservicex.net/globalweather.asmx?wsdl”
$Proxy = New-WebServiceProxy -uri $URI -namespace WebServiceProxy
The properties of the new Web service proxy are displayed by printing the value stored in the $Proxy variable as shown here:
PS C:Usersed.NWTRADERS> $proxy
SoapVersion : Default
AllowAutoRedirect : False
CookieContainer :
ClientCertificates : {}
EnableDecompression : False
UserAgent : Mozilla/4.0 (compatible; MSIE 6.0; MS Web Services Client Protoco
l 2.0.50727.4927)
Proxy :
UnsafeAuthenticatedConnectionSharing : False
Credentials :
UseDefaultCredentials : False
ConnectionGroupName :
PreAuthenticate : False
Url : http://www.webservicex.net/globalweather.asmx
RequestEncoding :
Timeout : 100000
Site :
Container :
Once the WebServiceProxy.GlobalWeather object is created, the GetCitiesByCountry method is called. The Get-Member cmdlet can be used to provide a clue to the input required by the GetCitiesByCountry method (although it would seem rather obvious that the method wants a string that represents the country to query). This is shown here:
PS C:Usersed.NWTRADERS> $Proxy | Get-Member -Name GetCitiesByCountry
TypeName: WebServiceProxy.GlobalWeather
Name MemberType Definition
—- ———- ———-
GetCitiesByCountry Method string GetCitiesByCountry(string CountryName)
The data that is returned by the GetCitiesByCountry method is in the form of a data set with tables that represent each city/country combination. This is seen here:
PS C:Usersed.NWTRADERS> $Proxy.GetCitiesByCountry(“mexico”)
<NewDataSet>
<Table>
<Country>Mexico</Country>
<City>Acapulco / G. Alvarez</City>
</Table>
<Table>
<Country>Mexico</Country>
<City>Aerop. Internacional Monterrey, N. L.</City>
</Table>
<Table>
<Country>Mexico</Country>
<City>Aguascalientes, Ags.</City>
</Table>
<Table>
<Country>Mexico</Country>
<City>Bahias De Huatulco</City>
</Table>
<Table>
<Country>Mexico</Country>
<City>Cuernavaca, Mor.</City>
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