(Swift 2) DynamoDB - DeleteItem

Deletes a single item in a table by primary key. You can perform a conditional delete operation that deletes the item if it exists, or if it has an expected attribute value.

For more information, see https://docs.aws.amazon.com/amazondynamodb/latest/APIReference/API_DeleteItem.html

Chilkat Downloads for the Swift Programming Language MAC OS X (Cocoa) Objective-C/Swift Libs iOS Objective-C/Swift Libs

func chilkatTest() {
    let rest = CkoRest()
    var success: Bool

    // Implements the following CURL command:

    // curl -X POST https://dynamodb.us-west-2.amazonaws.com/ \
    //   -H "Accept-Encoding: identity" \
    //   -H "Content-Type: application/x-amz-json-1.0" \
    //   -H "Authorization: AWS4-HMAC-SHA256 Credential=<Credential>, SignedHeaders=<Headers>, Signature=<Signature>" \
    //   -H "X-Amz-Date: <Date>" \
    //   -H "X-Amz-Target: DynamoDB_20120810.DeleteItem" \
    //   -d '{
    //     "TableName": "Thread",
    //     "Key": {
    //         "ForumName": {
    //             "S": "Amazon DynamoDB"
    //         },
    //         "Subject": {
    //             "S": "How do I update multiple items?"
    //         }
    //     },
    //     "ConditionExpression": "attribute_not_exists(Replies)",
    //     "ReturnValues": "ALL_OLD"
    // }'

    // Use the following online tool to generate REST code from a CURL command
    // Convert a cURL Command to REST Source Code

    let authAws = CkoAuthAws()
    authAws.AccessKey = "AWS_ACCESS_KEY"
    authAws.SecretKey = "AWS_SECRET_KEY"
    // Don't forget to change the region to your particular region. (Also make the same change in the call to Connect below.)
    authAws.Region = "us-west-2"
    authAws.ServiceName = "dynamodb"
    // SetAuthAws causes Chilkat to automatically add the following headers: Authorization, X-Amz-Date
    rest.SetAuthAws(authAws)

    // URL: https://dynamodb.us-west-2.amazonaws.com/
    var bTls: Bool = true
    var port: Int = 443
    var bAutoReconnect: Bool = true
    success = rest.Connect("dynamodb.us-west-2.amazonaws.com", port: port, tls: bTls, autoReconnect: bAutoReconnect)
    if success != true {
        print("ConnectFailReason: \(rest.ConnectFailReason.intValue)")
        print("\(rest.LastErrorText)")
        return
    }

    // Note: The above code does not need to be repeatedly called for each REST request.
    // The rest object can be setup once, and then many requests can be sent.  Chilkat will automatically
    // reconnect within a FullRequest* method as needed.  It is only the very first connection that is explicitly
    // made via the Connect method.

    // Use this online tool to generate code from sample JSON:
    // Generate Code to Create JSON

    // The following JSON is sent in the request body.

    // {
    //   "TableName": "Thread",
    //   "Key": {
    //     "ForumName": {
    //       "S": "Amazon DynamoDB"
    //     },
    //     "Subject": {
    //       "S": "How do I update multiple items?"
    //     }
    //   },
    //   "ConditionExpression": "attribute_not_exists(Replies)",
    //   "ReturnValues": "ALL_OLD"
    // }

    let json = CkoJsonObject()
    json.UpdateString("TableName", value: "Thread")
    json.UpdateString("Key.ForumName.S", value: "Amazon DynamoDB")
    json.UpdateString("Key.Subject.S", value: "How do I update multiple items?")
    json.UpdateString("ConditionExpression", value: "attribute_not_exists(Replies)")
    json.UpdateString("ReturnValues", value: "ALL_OLD")

    rest.AddHeader("Content-Type", value: "application/x-amz-json-1.0")
    rest.AddHeader("X-Amz-Target", value: "DynamoDB_20120810.DeleteItem")
    rest.AddHeader("Accept-Encoding", value: "identity")

    let sbRequestBody = CkoStringBuilder()
    json.EmitSb(sbRequestBody)
    let sbResponseBody = CkoStringBuilder()
    success = rest.FullRequestSb("POST", uriPath: "/", requestBody: sbRequestBody, responseBody: sbResponseBody)
    if success != true {
        print("\(rest.LastErrorText)")
        return
    }

    var respStatusCode: Int = rest.ResponseStatusCode.intValue
    print("response status code = \(respStatusCode)")
    if respStatusCode >= 400 {
        print("Response Status Code = \(respStatusCode)")
        print("Response Header:")
        print("\(rest.ResponseHeader)")
        print("Response Body:")
        print("\(sbResponseBody.GetAsString())")
        return
    }

    let jsonResponse = CkoJsonObject()
    jsonResponse.LoadSb(sbResponseBody)

    jsonResponse.EmitCompact = false
    print("\(jsonResponse.Emit())")

    // Sample JSON response:
    // (Sample code for parsing the JSON response is shown below)

    // {
    //   "Attributes": {
    //     "LastPostedBy": {
    //       "S": "fred@example.com"
    //     },
    //     "ForumName": {
    //       "S": "Amazon DynamoDB"
    //     },
    //     "LastPostDateTime": {
    //       "S": "201303201023"
    //     },
    //     "Tags": {
    //       "SS": [
    //         "Update",
    //         "Multiple Items",
    //         "HelpMe"
    //       ]
    //     },
    //     "Subject": {
    //       "S": "How do I update multiple items?"
    //     },
    //     "Message": {
    //       "S": "I want to update multiple items in a single call. What's the best way to do that?"
    //     }
    //   }
    // }

    // Sample code for parsing the JSON response...
    // Use the following online tool to generate parsing code from sample JSON:
    // Generate Parsing Code from JSON

    var strVal: String?

    var AttributesLastPostedByS: String? = jsonResponse.StringOf("Attributes.LastPostedBy.S")
    var AttributesForumNameS: String? = jsonResponse.StringOf("Attributes.ForumName.S")
    var AttributesLastPostDateTimeS: String? = jsonResponse.StringOf("Attributes.LastPostDateTime.S")
    var AttributesSubjectS: String? = jsonResponse.StringOf("Attributes.Subject.S")
    var AttributesMessageS: String? = jsonResponse.StringOf("Attributes.Message.S")
    var i: Int = 0
    var count_i: Int = jsonResponse.SizeOfArray("Attributes.Tags.SS").intValue
    while i < count_i {
        jsonResponse.I = i
        strVal = jsonResponse.StringOf("Attributes.Tags.SS[i]")
        i = i + 1
    }


}