Timestamp API will help you to timestamp individual data, track document versions, and validate already existing timestamps.

This is achieved through two functionalities:

• Timestamps: Designed for single-point-in-time data anchoring, offering an immutable record of your data's existence on the blockchain.
• Records: Introduce an enhanced layer of traceability by timestamping various versions of a document under a single record identifier, providing a holistic view of its history.

Creating Timestamps: A Step-by-Step Guide

Step 1. Load the Legal Entity

Load the keys of the legal entity

Command

==> using user ES256K did1 <LE_PRIVATE_KEY_ES256K> <LE_DID>
==> using user ES256 did1 <LE_PRIVATE_KEY_ES256> <LE_DID>

Now connect the wallet with the pilot environment:

Command

==> env pilot

Step 2. Request an access token

Request an access token to the authorisation API with the scope timestamp_write:

Command

==> resAuthTimestamp: authorisation auth timestamp_write_presentation ES256

Now load the access token:

Command

==> using token resAuthTimestamp.access_token

Step 3. Create a Timestamp

Interact with Timestamp API to timestamp some data:

Command

==> timestamp timestampHashes {"test": "some data"}

Output

{
  "data": {
    "test": "some data"
  },
  "id": "uEiAQjTSfJoekQZpuNe43jEm11_VFCSNagLOqsk81Tnf-aQ"
}

now you can check the timestamped data:

Command

==> timestamp get /timestamps/uEiAQjTSfJoekQZpuNe43jEm11_VFCSNagLOqsk81Tnf-aQ

Output

{
  "hash": "mEiCFEY+9nffGmiCIEU1angy1JvIkLayCumzH2TfYLqCLDw",
  "timestampedBy": "0xA4B6C8710f6bF233b8b480498916DEC224A5a891",
  "blockNumber": 4024912,
  "timestamp": "2023-12-15T16:49:09.000Z",
  "data": "0x7b2274657374223a22736f6d652064617461227d",
  "transactionHash": "0x19197878626e114811a4011d0d3ff432eaacbdd5eb37466f1b94f73ff03066de"
}

Congratulations!

You have timestamped data in Timestamp API

Records

With Timestamp API you can also create records containing a history of changes of a specific data. Let's see an example.

First let's create a new record with some data:

Command

==> timestamp timestampRecordHashes {"data": "my data"}

Output

Timestamp record hashes. Record Id:

{
  "blockNumber": "0x3d6a55",
  "recordId": "0x07b041928382a488c150840cd1c7a24f6b658a82d969961be831c820fd998842",
  "multibase64urlRecordId": "uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI",
  "hashValue": "0x37926887dc319ac87cda01caf411bccb9ab8933d97cf3c2d57d3e13aa8bad580"
}

Now let's timestamp new data using this record ID:

Command

==> timestamp timestampRecordVersionHashes 0x07b041928382a488c150840cd1c7a24f6b658a82d969961be831c820fd998842 {"data": "my data updated"}

Now get the versions stored in the record:

Command

==> timestamp get /records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI

Output

{
  "ownerIds": ["0xa4b6c8710f6bf233b8b480498916dec224a5a891"],
  "revokedOwnerIds": [],
  "firstVersionTimestamps": [
    "0x37926887dc319ac87cda01caf411bccb9ab8933d97cf3c2d57d3e13aa8bad580"
  ],
  "lastVersionTimestamps": [
    "0x66f27c170fb85e96b253673d035214528929f952424d0e5ab4125f4172d6c696"
  ],
  "totalVersions": 2
}

Command

==> timestamp get /records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions

Output

{
  "self": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions?page[after]=1&page[size]=10",
  "items": [
    {
      "versionId": 0,
      "href": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions/0"
    },
    {
      "versionId": 1,
      "href": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions/1"
    }
  ],
  "total": 2,
  "pageSize": 10,
  "links": {
    "first": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions?page[after]=1&page[size]=10",
    "prev": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions?page[after]=1&page[size]=10",
    "next": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions?page[after]=1&page[size]=10",
    "last": "https://api-pilot.ebsi.eu/timestamp/v4/records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions?page[after]=1&page[size]=10"
  }
}

Command

==> timestamp get /records/uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI/versions/0

Output

{
  "hashes": [
    "0x37926887dc319ac87cda01caf411bccb9ab8933d97cf3c2d57d3e13aa8bad580"
  ],
  "info": [
    {
      "info": "57b1b531f1535d5214c42551"
    }
  ]
}

Compute the multibase64url of the sha256 of this hash:

Command

==> tId: compute timestampId 0x37926887dc319ac87cda01caf411bccb9ab8933d97cf3c2d57d3e13aa8bad580
uEiDvUzJcns92jVdmFX9Ftj-VdmRcXdzrURU2w7bll1a56Q

Let's get this timestamp:

Command

==> timestamp get /timestamps/ tId

Output

{
  "hash": "mEiA3kmiH3DGayHzaAcr0EbzLmriTPZfPPC1X0+E6qLrVgA",
  "timestampedBy": "0xA4B6C8710f6bF233b8b480498916DEC224A5a891",
  "blockNumber": 4024917,
  "timestamp": "2023-12-15T16:49:49.000Z",
  "data": "0x7b2264617461223a226d792064617461227d",
  "transactionHash": "0xc0e703f2791487d9ef5982926c7a9c064d3cb053fba8640610b7959c13893896"
}

Command

==> compute decodeHex 0x7b2264617461223a226d792064617461227d

Output

{ "data": "my data" }

At the same time you can compute the record Id from address, blockNumber, and hash (this hash must be the first version of the record):

Command

==> compute recordId 0xA4B6C8710f6bF233b8b480498916DEC224A5a891 4024917 0x37926887dc319ac87cda01caf411bccb9ab8933d97cf3c2d57d3e13aa8bad580
uB7BBkoOCpIjBUIQM0ceiT2tlioLZaZYb6DHIIP2ZiEI