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 |
type |
State transition type ( |
ownerId |
Identity submitting the document(s) |
transitions |
Document |
signaturePublicKeyId |
The |
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.