Document#

Overview#

Dash Platform is based on document-oriented database concepts and uses related terminology. In short, JSON documents are stored into document collections which can then be fetched back using a query language similar to common document-oriented databases like MongoDB, CouchDB, or Firebase.

Documents are defined in an application’s Data Contract and represent the structure of application-specific data. Each document consists of one or more fields and the indices necessary to support querying.

Details#

Base Fields#

Dash Platform Protocol (DPP) defines a set of base fields that must be present in all documents. For the reference implementation, the base fields shown below are defined in the document base schema.

Field Name

Description

$id

The document ID (32 bytes)

$type

Document type defined in the referenced contract

$revision

Document revision (=>1)

$dataContract

Data contract the document is associated with

$ownerId

Identity of the user submitting the document (32 bytes)

$createdAt

Time (in milliseconds) the document was created

$updatedAt

Time (in milliseconds) the document was last updated

🚧 Timestamp fields

Note: The $createdAt and $updatedAt fields will only be present in documents that add them to the list of required properties.

Data Contract Fields#

Each application defines its own fields via document definitions in its data contract. Details of the DPNS data contract documents are described below as an example. This contract defines two document types (preorder and domain) and provides the functionality described in the Name Service explanation.

Document Type

Field Name

Data Type

preorder

saltedDomainHash

string

domain

label

string

domain

normalizedLabel

string

domain

parentDomainName

string

domain

normalizedParentDomainName

string

domain

preorderSalt

array (bytes)

domain

records

object

domain

records.dashUniqueIdentityId

array (bytes)

domain

records.dashAliasIdentityId

array (bytes)

domain

subdomainRules

object

domain

subdomainRules.allowSubdomains

boolean

Example Document#

The following example shows the structure of a DPNS domain document as output from JSON.stringify(). Note the $ prefix indicating the base fields.

 {
  "$id": "3AhZ5h63ZrFJXfE3YP3iEFVxyndYWPMxR9fSEaMo67QJ",
  "$ownerId": "6TGHW8WBcNzFrWwAueGtqtAah7w98EELFZ7xdTHegnvH",
  "label": "DQ-Jasen-82083",
  "normalizedLabel": "dq-jasen-82083",
  "normalizedParentDomainName": "dash",
  "parentDomainName": "dash",
  "preorderSalt": "bcCSdtGqqZdXBQB4DDBIU2RPAwFDFt9tMr0LX6m5qCQ=",
  "records": {
    "dashUniqueIdentityId": "UQTRY+wqPyL27V7YjJadJdyXVBETj6CfzvqUg5aY5E4="
  },
  "subdomainRules": {
    "allowSubdomains": false
  },
  "$revision": 1,
  "$createdAt": null,
  "$updatedAt": null,
  "$dataContract": {
    // Truncated ...
   },
  "$type": "domain"
}

Document Submission#

Once a document has been created, it must be encapsulated in a State Transition to be sent to the platform. The structure of a document state transition is shown below. For additional details, see the State Transition explanation.

Field Name

Description

protocolVersion

Dash Platform Protocol version (currently 1)

type

State transition type (1 for documents)

ownerId

Identity submitting the document(s)

transitions

Document create, replace, or delete transitions (up to 10 objects)

signaturePublicKeyId

The id of the identity public key that signed the state transition

signature

Signature of state transition data

Document Create#

The document create transition is used to create a new document on Dash Platform. The document create transition extends the base schema to include the following additional fields:

Field

Type

Description

$entropy

array (32 bytes)

Entropy used in creating the document ID

$createdAt

integer

(Optional) Time (in milliseconds) the document was created

$updatedAt

integer

(Optional) Time (in milliseconds) the document was last updated

Document Replace#

The document replace transition is used to update the data in an existing Dash Platform document. The document replace transition extends the base schema to include the following additional fields:

Field

Type

Description

$revision

integer

Document revision (=> 1)

$updatedAt

integer

(Optional) Time (in milliseconds) the document was last updated

Document Delete#

The document delete transition is used to delete an existing Dash Platform document. It only requires the fields found in the base document transition.

📘

For more detailed information, see the Platform Protocol Reference - Document page.