(SQL Server) Initialize an HTTP Request from a URL

Demonstrates how to initialize an HTTP request object from a URL.

Chilkat ActiveX Downloads ActiveX for 32-bit and 64-bit Windows

-- Important: See this note about string length limitations for strings returned by sp_OAMethod calls.
--
CREATE PROCEDURE ChilkatSample
AS
BEGIN
    DECLARE @hr int
    -- Important: Do not use nvarchar(max).  See the warning about using nvarchar(max).
    DECLARE @sTmp0 nvarchar(4000)
    DECLARE @sTmp1 nvarchar(4000)
    DECLARE @req int
    -- Use "Chilkat_9_5_0.HttpRequest" for versions of Chilkat < 10.0.0
    EXEC @hr = sp_OACreate 'Chilkat.HttpRequest', @req OUT
    IF @hr <> 0
    BEGIN
        PRINT 'Failed to create ActiveX component'
        RETURN
    END

    -- Loads the HTTP request object from a URL
    EXEC sp_OAMethod @req, 'SetFromUrl', NULL, 'https://www.youtube.com/watch?v=fAZdTchQePc&t=45s'

    -- The verb will be "GET"

    EXEC sp_OAGetProperty @req, 'HttpVerb', @sTmp0 OUT
    PRINT 'verb = ' + @sTmp0
    -- The path will be "/watch"

    EXEC sp_OAGetProperty @req, 'Path', @sTmp0 OUT
    PRINT 'path = ' + @sTmp0

    -- The output of this loop will be
    -- 0) v: fAZdTchQePc
    -- 1) t: 45s
    DECLARE @i int

    DECLARE @numParams int
    EXEC sp_OAGetProperty @req, 'NumParams', @numParams OUT
    SELECT @i = 0
    WHILE @i <= @numParams - 1
      BEGIN

        EXEC sp_OAMethod @req, 'GetParamName', @sTmp0 OUT, @i

        EXEC sp_OAMethod @req, 'GetParamValue', @sTmp1 OUT, @i
        PRINT @i + ') ' + @sTmp0 + ': ' + @sTmp1
        SELECT @i = @i + 1
      END

    -- View the request that would be sent if SynchronousRequest is called.
    -- The HTTP request will be a GET that looks like this:
    -- 
    --     GET /watch?v=fAZdTchQePc&t=45s HTTP/1.1
    --     Host: domain
    -- 
    -- Note: The HOST header will automatically get filled in with the actual domain when SynchronousRequest is called.

    EXEC sp_OAMethod @req, 'GenerateRequestText', @sTmp0 OUT
    PRINT @sTmp0

    -- We can add additional params
    EXEC sp_OAMethod @req, 'AddParam', NULL, 'artist', 'Richard Bona'
    EXEC sp_OAMethod @req, 'AddParam', NULL, 'musicType', 'Jazz'
    EXEC sp_OAMethod @req, 'AddParam', NULL, 'festival', 'Estival Jazz Lugano'
    EXEC sp_OAMethod @req, 'AddParam', NULL, 'year', '2008'

    -- Now examine the request that would be sent
    -- 
    --     GET /watch?v=fAZdTchQePc&t=45s&artist=Richard%20Bona&musicType=Jazz&festival=Estival%20Jazz%20Lugano&year=2008 HTTP/1.1
    --     Host: domain
    -- 
    EXEC sp_OAMethod @req, 'GenerateRequestText', @sTmp0 OUT
    PRINT @sTmp0

    -- We can remove a parameter:
    EXEC sp_OAMethod @req, 'RemoveParam', NULL, 't'
    EXEC sp_OAMethod @req, 'GenerateRequestText', @sTmp0 OUT
    PRINT @sTmp0

    -- What happens if we change the request from a GET to a POST?
    EXEC sp_OASetProperty @req, 'HttpVerb', 'POST'
    -- The request will now look like this:
    -- 
    --    POST /watch HTTP/1.1
    --    Host: domain
    --    Content-Length: 93
    --    
    --    v=fAZdTchQePc&artist=Richard%20Bona&musicType=Jazz&festival=Estival%20Jazz%20Lugano&year=2008
    -- 
    EXEC sp_OAMethod @req, 'GenerateRequestText', @sTmp0 OUT
    PRINT @sTmp0

    -- What happens if we make it a multipart/form-data?
    EXEC sp_OASetProperty @req, 'ContentType', 'multipart/form-data'
    -- Now the POST looks like this:
    --    
    --    POST /watch HTTP/1.1
    --    Content-Type: multipart/form-data; boundary=------------020906020106050705030807
    --    Host: domain
    --    Content-Length: 545
    --    
    --    --------------020906020106050705030807
    --    Content-Disposition: form-data; name="v"
    --    
    --    fAZdTchQePc
    --    --------------020906020106050705030807
    --    Content-Disposition: form-data; name="artist"
    --    
    --    Richard Bona
    --    --------------020906020106050705030807
    --    Content-Disposition: form-data; name="musicType"
    --    
    --    Jazz
    --    --------------020906020106050705030807
    --    Content-Disposition: form-data; name="festival"
    --    
    --    Estival Jazz Lugano
    --    --------------020906020106050705030807
    --    Content-Disposition: form-data; name="year"
    --    
    --    2008
    --    --------------020906020106050705030807--

    EXEC sp_OAMethod @req, 'GenerateRequestText', @sTmp0 OUT
    PRINT @sTmp0

    EXEC @hr = sp_OADestroy @req


END
GO