GetBlock
Returns a block object at a specified address in a journal. Also returns a proof of the
specified block for verification if DigestTipAddress
is provided.
For information about the data contents in a block, see Journal contents in the Amazon QLDB Developer Guide.
If the specified ledger doesn't exist or is in DELETING
status, then throws
ResourceNotFoundException
.
If the specified ledger is in CREATING
status, then throws
ResourcePreconditionNotMetException
.
If no block exists with the specified address, then throws
InvalidParameterException
.
Request Syntax
POST /ledgers/name
/block HTTP/1.1
Content-type: application/json
{
"BlockAddress": {
"IonText": "string
"
},
"DigestTipAddress": {
"IonText": "string
"
}
}
URI Request Parameters
The request uses the following URI parameters.
- name
-
The name of the ledger.
Length Constraints: Minimum length of 1. Maximum length of 32.
Pattern:
(?!^.*--)(?!^[0-9]+$)(?!^-)(?!.*-$)^[A-Za-z0-9-]+$
Required: Yes
Request Body
The request accepts the following data in JSON format.
- BlockAddress
-
The location of the block that you want to request. An address is an Amazon Ion structure that has two fields:
strandId
andsequenceNo
.For example:
{strandId:"BlFTjlSXze9BIh1KOszcE3",sequenceNo:14}
.Type: ValueHolder object
Required: Yes
- DigestTipAddress
-
The latest block location covered by the digest for which to request a proof. An address is an Amazon Ion structure that has two fields:
strandId
andsequenceNo
.For example:
{strandId:"BlFTjlSXze9BIh1KOszcE3",sequenceNo:49}
.Type: ValueHolder object
Required: No
Response Syntax
HTTP/1.1 200
Content-type: application/json
{
"Block": {
"IonText": "string"
},
"Proof": {
"IonText": "string"
}
}
Response Elements
If the action is successful, the service sends back an HTTP 200 response.
The following data is returned in JSON format by the service.
- Block
-
The block data object in Amazon Ion format.
Type: ValueHolder object
- Proof
-
The proof object in Amazon Ion format returned by a
GetBlock
request. A proof contains the list of hash values required to recalculate the specified digest using a Merkle tree, starting with the specified block.Type: ValueHolder object
Errors
For information about the errors that are common to all actions, see Common Errors.
- InvalidParameterException
-
One or more parameters in the request aren't valid.
HTTP Status Code: 400
- ResourceNotFoundException
-
The specified resource doesn't exist.
HTTP Status Code: 404
- ResourcePreconditionNotMetException
-
The operation failed because a condition wasn't satisfied in advance.
HTTP Status Code: 412
See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following: