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(JavaScript) 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
var success = false;
var rest = new CkRest();
// 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
var authAws = new CkAuthAws();
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 = true;
var port = 443;
var bAutoReconnect = true;
success = rest.Connect("dynamodb.us-west-2.amazonaws.com",port,bTls,bAutoReconnect);
if (success !== true) {
console.log("ConnectFailReason: " + rest.ConnectFailReason);
console.log(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"
// }
var json = new CkJsonObject();
json.UpdateString("TableName","Thread");
json.UpdateString("Key.ForumName.S","Amazon DynamoDB");
json.UpdateString("Key.Subject.S","How do I update multiple items?");
json.UpdateString("ConditionExpression","attribute_not_exists(Replies)");
json.UpdateString("ReturnValues","ALL_OLD");
rest.AddHeader("Content-Type","application/x-amz-json-1.0");
rest.AddHeader("X-Amz-Target","DynamoDB_20120810.DeleteItem");
rest.AddHeader("Accept-Encoding","identity");
var sbRequestBody = new CkStringBuilder();
json.EmitSb(sbRequestBody);
var sbResponseBody = new CkStringBuilder();
success = rest.FullRequestSb("POST","/",sbRequestBody,sbResponseBody);
if (success !== true) {
console.log(rest.LastErrorText);
return;
}
var respStatusCode = rest.ResponseStatusCode;
console.log("response status code = " + respStatusCode);
if (respStatusCode >= 400) {
console.log("Response Status Code = " + respStatusCode);
console.log("Response Header:");
console.log(rest.ResponseHeader);
console.log("Response Body:");
console.log(sbResponseBody.GetAsString());
return;
}
var jsonResponse = new CkJsonObject();
jsonResponse.LoadSb(sbResponseBody);
jsonResponse.EmitCompact = false;
console.log(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;
var AttributesLastPostedByS = jsonResponse.StringOf("Attributes.LastPostedBy.S");
var AttributesForumNameS = jsonResponse.StringOf("Attributes.ForumName.S");
var AttributesLastPostDateTimeS = jsonResponse.StringOf("Attributes.LastPostDateTime.S");
var AttributesSubjectS = jsonResponse.StringOf("Attributes.Subject.S");
var AttributesMessageS = jsonResponse.StringOf("Attributes.Message.S");
var i = 0;
var count_i = jsonResponse.SizeOfArray("Attributes.Tags.SS");
while (i < count_i) {
jsonResponse.I = i;
strVal = jsonResponse.StringOf("Attributes.Tags.SS[i]");
i = i+1;
}
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