dropzone-lib

Class: Item

messages~ Item

new Item(connection, attrs)

An Item listing. Either a create (DZITCRTE) or update (DZITUPDT), depending on the attributes supplied.

receiverAddr: Newly created items will have no receiver, and will be automatically sent to an appropriate burn address that will enable item discovery on the network. Updates to an item should be addressed to the seller's public key, from with the item was originally declared.

NOTE: All attributes that are specified below are also getter properties that can be accessed on this instantiated object.

Parameters:
Name Type Description
connection Driver

blockchain connection
attrs object

Attributes that this Item contains

Properties
Name Type Description
latitude Float

DZITCRTE only/required: Listing Latitude
longitude Float

DZITCRTE only/required: Listing Longitude
radius Integer

DZITCRTE only/required: Listing precision (in meters)
description String

This is the description of the item, and can contain text and/or URL of the seller for use in presenting to the buyer. Hashtags are highly encouraged as a mechanism for identifying the item (i.e., #bible).
priceCurrency String

The denomination of the price. ISO4217 codes are acceptable, as well as "BTC." Nonce-like constructions should also be supported (i.e., DOGE).
priceInUnits Integer

The price of the specified item denominated in cents, or satoshis, etc.
expirationIn Integer

The expiration time of the item. "Times" are to be indicated in the number of blocks that this listing is available for. Omitting this field indicates no expiration. Note that clients will likely override the seller's preference to list an item for a very long time by restricting the block depth of users' searches.
createTxid String

DZITUPDT only/required: This integer specifies the previously created transaction id being updated.

Extends

Methods

<static> distanceBetween(lat1, lon1, lat2, lon2)

Compute the distance between two pairs of lat/lon's. Based on the haversine formula, pulled from : http://www.movable-type.co.uk/scripts/latlong.html

Parameters:
Name Type Description
lat1 Integer
lon1 Integer
lat2 Integer
lon2 Integer

<static> findCreatesSinceBlock(connection, startingAt, blockDepth, cb)

/ Returns all Items created* since (and including) the provided block to the provided depth. Note thath these are items and not listings, so as to query faster. Items are returned in the order of newest to oldest.

Parameters:
Name Type Description
connection Driver

blockchain connection
startingAt Integer

Block Height to begin search from
blockDepth Integer

Block Depth to which the search should descend
cb function

Callback to receive the item creation messages in the form: function(err, items).

<static> findInRadius(connection, startingAt, blockDepth, lat, lon, inMeters, cb)

/ Returns all Items created* since (and including) the provided block. This call basically mirrors the functionality of findCreatesSinceBlock, however, the additional lat/lon/inMeters parameter is used to filter results based on geographic proximity. This returns all items created in the specified timeframe that were declared within the specified inMeters from the lat/lot.

Parameters:
Name Type Description
connection Driver

blockchain connection
startingAt Integer

Block Height to begin search from
blockDepth Integer

Block Depth to which the search should descend
lat Integer

the Latitude corresponding to the buyer's location
lon Integer

the Longitude corresponding to the buyer's location
inMeters Integer

the number of meters to search for listings around the provided lat/lon
cb function

Callback to receive the item creation messages in the form: function(err, items).

isValid(cb)

Determine whether this message has been properly formatted, and is 'in consensus' with the Drop Zone protocol. Further documentation for this validation result, and it's error messages can be found in the async-validate library.

Parameters:
Name Type Description
cb function

Callback to receive the results of the validity test form: function(err, res)
Inherited From:

save(cb)

Save this message into the blockchain, if it hasn't yet been persisted, and was instantiated without a txid.

NOTE: Validation is not performed as part of this method. It's entirely possible to persist a message into the blockchain that will be ommitted from search/scan results by clients. Validation is performed as part of #find() not #save().

Parameters:
Name Type Description
cb function

Callback which receives the mempool-persisted message in the form: function(err, message)

NOTE: Due to transaction-maleability, the persisted txid may change at the time of actual confirmation. This method merely broadcasts the message into the mempool.
Inherited From:

toTransaction()

Return a hash object representing the serialized components of this transaction suitable for passing onto TxEncode.

Inherited From:
Returns:
Type
object