(PureBasic) S3 Get Bucket Policy

Demonstrates how to send a GET request to fetch the policy of a specified bucket. The following information is quoted from the AWS REST API reference documentation at http://docs.aws.amazon.com/AmazonS3/latest/API/RESTBucketGETpolicy.html

To use this operation, you must have GetPolicy permissions on the specified bucket, and you must be the bucket owner.

If you don't have GetPolicy permissions, Amazon S3 returns a 403 Access Denied error. If you have the correct permissions, but you're not the bucket owner, Amazon S3 returns a 405 Method Not Allowed error. If the bucket does not have a policy, Amazon S3 returns a 404 Policy Not found error. There are restrictions about who can create bucket policies and which objects in a bucket they can apply to. For more information, go to Using Bucket Policies.

Important: This example requires Chilkat v9.5.0.66 or greater.

Chilkat PureBasic Module Download Chilkat PureBasic Module

IncludeFile "CkAuthAws.pb"
IncludeFile "CkJsonObject.pb"
IncludeFile "CkRest.pb"

Procedure ChilkatExample()

    ; This example requires the Chilkat API to have been previously unlocked.
    ; See Global Unlock Sample for sample code.

    ; Important: This example requires Chilkat v9.5.0.66 or greater.

    rest.i = CkRest::ckCreate()
    If rest.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    ; Connect to the Amazon AWS REST server in the desired region.
    bTls.i = 1
    port.i = 443
    bAutoReconnect.i = 1
    success.i = CkRest::ckConnect(rest,"s3-us-west-2.amazonaws.com",port,bTls,bAutoReconnect)

    ; Provide AWS credentials.
    authAws.i = CkAuthAws::ckCreate()
    If authAws.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkAuthAws::setCkAccessKey(authAws, "AWS_ACCESS_KEY")
    CkAuthAws::setCkSecretKey(authAws, "AWS_SECRET_KEY")
    CkAuthAws::setCkServiceName(authAws, "s3")

    ; This particular bucket is in the Oregon region, as opposed to the US Standard,
    ; therefore the Region must be set appropriately.
    ; Also note that we connected to "s3-us-west-2.amazonaws.com".
    CkAuthAws::setCkRegion(authAws, "us-west-2")

    success = CkRest::ckSetAuthAws(rest,authAws)

    ; Note: The above REST connection and setup of the AWS credentials
    ; can be done once.  After connecting, any number of REST calls can be made.
    ; The "auto reconnect" property passed to rest.Connect indicates that if
    ; the connection is lost, a REST method call will automatically reconnect
    ; if needed.
    ; --------------------------------------------------------------------------

    ; Set the bucket name via the HOST header.
    ; In this case, the bucket name is "chilkat.ocean".
    ; Note that the Host header should use "bucketName.s3.amazonaws.com", not "bucketName.s3-us-west-2.amazonaws.com"
    CkRest::setCkHost(rest, "chilkat.ocean.s3.amazonaws.com")

    ; Get the policy.
    responseJsonStr.s = CkRest::ckFullRequestNoBody(rest,"GET","/?policy")
    If CkRest::ckLastMethodSuccess(rest) <> 1
        Debug CkRest::ckLastErrorText(rest)
        CkRest::ckDispose(rest)
        CkAuthAws::ckDispose(authAws)
        ProcedureReturn
    EndIf

    ; When successful, the S3 Storage service will respond with a 200 response code,
    ; with an XML body.  
    If CkRest::ckResponseStatusCode(rest) <> 200
        ; Examine the request/response to see what happened.
        Debug "response status code = " + Str(CkRest::ckResponseStatusCode(rest))
        Debug "response status text = " + CkRest::ckResponseStatusText(rest)
        Debug "response header: " + CkRest::ckResponseHeader(rest)
        Debug "response body: " + responseJsonStr
        Debug "---"
        Debug "LastRequestStartLine: " + CkRest::ckLastRequestStartLine(rest)
        Debug "LastRequestHeader: " + CkRest::ckLastRequestHeader(rest)
    EndIf

    Debug "response body: " + responseJsonStr

    ; Load the JSON and display in a more human-readable manner:
    json.i = CkJsonObject::ckCreate()
    If json.i = 0
        Debug "Failed to create object."
        ProcedureReturn
    EndIf

    CkJsonObject::ckLoad(json,responseJsonStr)
    CkJsonObject::setCkEmitCompact(json, 0)
    Debug CkJsonObject::ckEmit(json)

    ; Sample output:

    ; 	{ 
    ; 	  "Version": "2012-10-17",
    ; 	  "Statement": [
    ; 	    { 
    ; 	      "Effect": "Allow",
    ; 	      "Resource": "arn:aws:s3.asp">chilkat.ocean/",
    ; 	      "Principal": "*"
    ; 	    }
    ; 	  ]
    ; 	}
    ; 


    CkRest::ckDispose(rest)
    CkAuthAws::ckDispose(authAws)
    CkJsonObject::ckDispose(json)


    ProcedureReturn
EndProcedure