获取地球上哪个地方的天气

昨天我发布了一篇关于使用 Invoke-WebRequest 获取天气状况的热门文章。该功能使用雅虎网站，但实际上只适用于美国城市。因此，我还清理并修改了另一组高级 PowerShell 函数（需要 PowerShell 3），这些函数可以检索地球上可能任何位置的天气信息。您需要的第一条信息是您的 WOEID，即“地球上的位置 ID”。这是一个可以做到这一点的函数。

Function Get-Woeid {

<#
.Synopsis
   Retrieve WOEID information
.Description
    Search Yahoo's Geo Places for a WOEID (Where On Earth ID). You can search based on a postal code, or place name. Optionally, you can save the XML results to the pipeline.
.Parameter Search
    A search parameter such as a postal or zip code. You can also use a place name.
.Parameter AsXML
    Write the XML document to the pipeline.
.Example
PS C:\> get-woeid 89101

Country : US
Region  : Nevada
Postal  : 89101
Locale  : Las Vegas
WOEID   : 12795439

.Example
PS C:\> get-woeid -search "H1A0A1"

Region  : Quebec
Postal  : H1A 0A1
WOEID   : 55963829
Locale  : Montreal
Country : CA

.Example
PS C:\> get-woeid "Helsinki, Finland"

Country : FI
Region  : Uudenmaan maakunta
Postal  :
Locale  : Helsinki
WOEID   : 565346
.Example
PS C:\> get-woeid "Helsinki, Finland" | get-weather -unit C


Date              : Mon, 16 Feb 2015 4:49 pm EET
Location          : Helsinki, Finland
Temperature       : -2 C
Condition         : Fair
ForecastCondition : Clear
ForecastLow       : -6 C
ForecastHigh      : -2 C
.Example
PS C:\> [xml]$doc = get-woeid "omaha, ne" -AsXML
PS C:\> $doc.Save("c:\work\omahaid.xml")

The first command gets the raw XML document and the second command writes it to disk. Or you can explore the document interactively.

PS C:\> $doc.query.results.place.timezone

type                          woeid                         #text                       
----                          -----                         -----                       
Time Zone                     56043661                      America/Chicago  
.Inputs
    strings
.Outputs
    custom object
.Link
Invoke-RestMethod
    
.Notes
 NAME:      Get-Woeid
 VERSION:   3.0
 AUTHOR:    Jeffery Hicks
 LASTEDIT:  February 16, 2015
 
 Learn more about PowerShell:
 Essential PowerShell Learning Resources
 
#>

Param(
[parameter(Position=0,Mandatory,ValueFromPipeline,
HelpMessage="Enter a place name or postal (zip) code.")]
[string[]]$Search,
[switch]$AsXML
)

Begin {
    Write-Verbose "Starting $($myinvocation.mycommand)"
}

Process {
    foreach ($item in $search) {
        Write-Verbose "Querying for $search"
        $uri = "https://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20geo.places%20where%20text%3D'$ITEM'%20limit%201"
        
        Write-Verbose $uri
        [xml]$xml= Invoke-RestMethod -Uri $uri

        if ($AsXML) {
            Write-Verbose "Writing XML document"
            $xml
            Write-Verbose "Ending function"
            #bail out since we're done
            Return
        }

        if ($xml.query.results.place.woeid) {
            Write-Verbose "Parsing XML into an ordered hashtable"
            $hash = [ordered]@{
                WOEID   = $xml.query.results.place.woeid
                Locale  = $xml.query.results.place.locality1.'#text'
                Region  = $xml.query.results.place.admin1.'#text'
                Postal  = $xml.query.results.place.postal.'#text'
                Country = $xml.query.results.place.country.code            
            }
            Write-Verbose "Writing custom object"
            New-Object -TypeName PSObject -Property $hash

        } #if $xml
        else {
            Write-Warning "Failed to find anything for $item"
        }
    } #foreach
} #process

End {
    Write-Verbose "Ending $($myinvocation.mycommand)"
 }
} #end function

要使用该功能，您需要指定某种搜索条件，例如邮政编码或城市名称。

我将 WOEID 作为变量保存在 PowerShell 配置文件中。该函数也使用Invoke-RestMethod。我添加了一个参数来将 XML 文档写入管道，以防您想要修改函数并需要一些帮助来发现数据。第二个函数 Get-Weather 使用 WOIED 获取当前天气状况。它也使用 Invoke-RestMethod 来检索数据。然后使用 Select-XML 解析生成的 XML 文档以构建输出对象。

Function Get-Weather {

<#
.Synopsis
Retrieve weather information from Yahoo.com.
.Description
Using the Yahoo weather APIs, this function will retrieve weather information for the specified WOEID or "Where on Earth ID". If you don't know your WOED, open a web browser and go to http://weather.yahoo.com/. Enter in your zip or postal code. Your WOEID will be the number at the end of the url. 
Or you can use the Get-Woeid function.
    
A custom object is written to the pipeline and you can control how much information is displayed by specifying Basic, Extended or All for the Detail parameter.
    
Basic properties:
    Date,Location,Temperature,Condition,ForecastCondition,ForecastLow, and ForecastHigh. This is the default.
Extended properties:
	Basic properties plus WindChill,WindSpeed,Humidity,Barometer,Visibility,and Tomorrow.
All properties:
	Extended properties plus Sunrise,Sunset,City,Region,Zip,Latitude,Longitude,URL
 
.Parameter Woeid
Your WOEID, or "Where on Earth ID".
.Parameter Unit
Show temperature in Farenheit or Celsius
.Parameter Online
Open the web page in your default browser.
.Parameter AsXML
Write an XML document to the pipeline.
.Example
PS C:> get-weather 12795711

Date              : Mon, 16 Feb 2015 3:51 am PST
Location          : Beverly Hills, CA
Temperature       : 56 F
Condition         : Fair
ForecastCondition : Sunny
ForecastLow       : 55 F
ForecastHigh      : 72 F
.Example
PS C:\> get-weather 12795446 extended

Date              : Mon, 16 Feb 2015 6:56 am PST
Location          : Las Vegas, NV
Temperature       : 52 F
Condition         : Mostly Cloudy
ForecastCondition : Sunny
ForecastLow       : 49 F
ForecastHigh      : 77 F
WindChill         : 52 F
WindSpeed         : 9 mph
Humidity          : 35%
Barometer         : 29.95 in and steady
Visibility        : 10  mi
Tomorrow          : Tue 17 Feb 2015 Sunny Low 49F: High: 70F
.Example
PS C:\> 12795711,12795446,12762736 | Get-Weather -detail all | Format-Table City,Temperature,Condition,Sunrise,Sunset
City          Temperature Condition     Sunrise Sunset 
----          ----------- ---------     ------- ------ 
Beverly Hills 56 F        Fair          6:37 am 5:38 pm
Las Vegas     52 F        Mostly Cloudy 6:26 am 5:21 pm
Syracuse      -3 F        Partly Cloudy 7:01 am 5:34 pm
.Example
PS C:\> get-woeid "Bangor,ME" | get-weather 


Date              : Mon, 16 Feb 2015 9:51 am EST
Location          : Bangor, ME
Temperature       : 5 F
Condition         : Partly Cloudy
ForecastCondition : Partly Cloudy/Wind
ForecastLow       : -6 F
ForecastHigh      : 12 F
.Example
PS C:\> get-woeid "Juneau, AK","Miami,FL" | get-weather | Select Date,Location,Temperature


Date                                 Location                             Temperature
----                                 --------                             -----------
Mon, 16 Feb 2015 8:54 am AKST        Juneau, AK                           35 F
Mon, 16 Feb 2015 12:53 pm EST        Miami, FL                            75 F
.Inputs
Strings
.Outputs
Custom object
.Link
Invoke-RestMethod

.Link
Get-Woeid
Select-XML
    
.Notes
 NAME:      Get-Weather
 VERSION:   3.0
 AUTHOR:    Jeffery Hicks
 LASTEDIT:  February 16, 2015

 Learn more about PowerShell:
 Essential PowerShell Learning Resources

   ****************************************************************
   * DO NOT USE IN A PRODUCTION ENVIRONMENT UNTIL YOU HAVE TESTED *
   * THOROUGHLY IN A LAB ENVIRONMENT. USE AT YOUR OWN RISK.  IF   *
   * YOU DO NOT UNDERSTAND WHAT THIS SCRIPT DOES OR HOW IT WORKS, *
   * DO NOT USE IT OUTSIDE OF A SECURE, TEST SETTING.             *
   ****************************************************************
 
#>

[cmdletbinding(DefaultParameterSetName="detail")]

Param(
[Parameter(Position=0,Mandatory,HelpMessage="Enter a WOEID value",
ValueFromPipeline,
ValueFromPipelineByPropertyName
)]
[ValidateNotNullorEmpty()]
[string[]]$woeid,
    
[Parameter(Position=1,ParameterSetName="detail")]
[ValidateSet("Basic","Extended","All")]
[String]$Detail="Basic",

[ValidateSet("f","c")]
[String]$Unit="f",
    
[Parameter(ParameterSetName="online")]
[Switch]$Online,

[Parameter(ParameterSetName="xml")]
[Switch]$AsXML
    
)

Begin {    
	Write-Verbose "Starting $($myinvocation.mycommand)"
	
	#define property sets
	$BasicProp=@("Date","Location","Temperature","Condition","ForecastCondition",
	"ForecastLow","ForecastHigh")
	$ExtendedProp=$BasicProp
	$ExtendedProp+=@("WindChill","WindSpeed","Humidity","Barometer",
	"Visibility","Tomorrow")
	$AllProp=$ExtendedProp
	$AllProp+=@("Sunrise","Sunset","City","Region","Latitude",
	"Longitude","ID","URL")
	
	#unit must be lower case
	$Unit=$Unit.ToLower()
	Write-Verbose "Using unit $($unit.toLower())"
    
    #define base url string
    [string]$uribase = "http://weather.yahooapis.com/forecastrss"
    Write-Verbose "Base = $uribase"
 } #begin
 
Process {
    Write-Verbose "Processing"
    
	foreach ($id in $woeid) {
		Write-Verbose "Getting weather info for woeid: $id"
	    
	    #define a uri for the given WOEID
        [string]$uri = "{0}?w={1}&u={2}" -f $uribase,$id,$unit
	     if ($online) {
	    	Write-Verbose "Opening $uri in web browser"
	    	Start-Process -FilePath $uri
            #bail out since there's nothing else to do.
            Return
	    }
        Write-Verbose "Downloading $uri"
	    [xml]$xml= Invoke-WebRequest -uri $uri

        if ($AsXML) {
            Write-Verbose "Writing XML document"
            $xml
            Write-Verbose "Ending function"
            #bail out since we're done
            Return
        }

	    if ($xml.rss.channel.item.Title -eq "City not found") {
	        Write-Warning "Could not find a location for $id"}
	    else {
	    	Write-Verbose "Processing xml"
	    	
	        #initialize a new hash table
	        $properties=@{}
	    	<#
            get the yweather nodes	
        	yweather information comes from a different namespace so we'll
            use Select-XML to extract the data. Parsing out all data regardless
            of requested detail since it doesn't take much effort. Later,
            only the requested detail will be written to the pipeline.
            #>

        	#define the namespace hash
        	$namespace=@{yweather=$xml.rss.yweather}
        	$units=(Select-Xml -xml $xml -XPath "//yweather:units" -Namespace $namespace ).node
	    	
	        $properties.Add("Condition",$xml.rss.channel.item.condition.text)
	        $properties.Add("Temperature","$($xml.rss.channel.item.condition.temp) $($units.temperature)")
            #convert Date to a [datetime] object
            $dt = $xml.rss.channel.item.condition.date.Substring(0,$xml.rss.channel.item.condition.Date.LastIndexOf("m")+1) -as [datetime]
	        $properties.Add("Date",$dt)
	    
	        #get forecast
            $properties.add("ForecastDate",$xml.rss.channel.item.forecast[0].date)
	        $properties.add("ForecastCondition",$xml.rss.channel.item.forecast[0].text )
	        $properties.Add("ForecastLow","$($xml.rss.channel.item.forecast[0].low) $($units.temperature)" )
	        $properties.Add("ForecastHigh","$($xml.rss.channel.item.forecast[0].high) $($units.temperature)" )
	        
	        #build tomorrow's foreacst
	        $t=$xml.rss.channel.item.forecast[1]
	        $tomorrow="{0} {1} {2} Low {3}{4}: High: {5}{6}" -f $t.day,$t.Date,$t.Text,$t.low, $($units.temperature),$t.high, $($units.temperature)
	        $properties.add("Tomorrow",$tomorrow)
	        
	        #get optional information
          	$properties.Add("Latitude",$xml.rss.channel.item.lat)
        	$properties.Add("Longitude",$xml.rss.channel.item.long)
        	$city=$xml.rss.channel.location.city
        	$properties.Add("City",$city)
        	$region=$xml.rss.channel.location.region
            $country=$xml.rss.channel.location.country
        	
        	if (-not ($region)) {
               #if no region found then use country
               Write-Verbose "No region found. Using Country"
                $region=$country
            }
            $properties.Add("Region",$region)
            $location="{0}, {1}" -f $city,$region
	        $properties.Add("Location",$location)	    	 
	        $properties.Add("ID",$id)
        	
            #get additional yweather information        	
        	$wind=(Select-Xml -xml $xml -XPath "//yweather:wind" -Namespace $namespace ).node
        	$astronomy=(Select-Xml -xml $xml -XPath "//yweather:astronomy" -Namespace $namespace ).node
        	$atmosphere=(Select-Xml -xml $xml -XPath "//yweather:atmosphere" -Namespace $namespace ).node
        	
        	$properties.Add("WindChill","$($wind.chill) $($units.temperature)")
        	$properties.Add("WindSpeed","$($wind.speed) $($units.speed)")
        	$properties.Add("Humidity","$($atmosphere.humidity)%")
        	$properties.Add("Visibility","$($atmosphere.visibility)  $($units.distance)")
        	
            #decode rising
        	switch ($atmosphere.rising) {
        		0 {$state="steady"}
        		1 {$state="rising"}
        		2 {$state="falling"}
        	}
         	$properties.Add("Barometer","$($atmosphere.pressure) $($units.pressure) and $state")
        	$properties.Add("Sunrise",$astronomy.sunrise)
        	$properties.Add("Sunset",$astronomy.sunset)
        	$properties.Add("url",$uri)
           
		   #create new object to hold values
		   $obj= New-Object -TypeName PSObject -Property $properties
		   
		   #write object and properties. Default is Basic
		   Switch ($detail) {
           "All"  {
		   	     Write-Verbose "Using All properties"
		   	     $obj | Select-Object -Property $AllProp
		    } #all
		   "Extended"  {
		   	    Write-Verbose "Using Extended properties"
		   	    $obj | Select-Object -Property $ExtendedProp
		   } #extended
		   Default {
		   	     Write-Verbose "Using Basic properties"
		   	     $obj | Select-Object -Property $BasicProp
		     } #default
	       } #Switch
	   } #processing XML
   } #foreach $id

 } #process
 
 End {
 	Write-Verbose "Ending $($myinvocation.mycommand)"
 }  #end 
    
} #end function

您还可以更改温度单位。

我将它们编写为两个单独的函数，我想我可以将 Get-Woeid 嵌套在 Get-Weather 中，尽管更好的选择可能是构建一个模块。我把它留给你。这些函数旨在利用管道绑定，以便您可以通过管道将 Get-Woeid 传递给 Get-Weather。

您甚至可以获得多个地点的天气。

该天气源包含大量信息，因此我创建了一个参数来控制要显示的详细信息量。您在上面看到的是基本信息。但还有‘延长’。

或者，您可以通过“全部”详细设置来查看所有内容。

注意到最后的那个网址了吗？最重要的是，您可以使用“在线”参数在浏览器中打开天气预报。

get-woeid 13244 | get-weather -Online

你有它。无论您身在何处，都可以查看天气。或者看看窗外。

享受。