EDDN/schemas/commodity-README.md

EDDN Commodity Schema

Introduction

Here we document how to take data from an ED Market Journal Event and properly structure it for sending to EDDN.

Please consult EDDN Schemas README for general documentation for a schema such as this.

Senders

The primary data source for this schema is the ED Journal event Market, and the additional file, Market.json, that it signals the writing of.

So, look for the Market event, and when it occurs open and read the Market.json file which contains the actual data. Treat that data as the event.

It is also possible to construct this data from a CAPI /market query.
See Using CAPI data below.

Statusflags

statusFlags is an optional augmentation that can be used to identify Producer, Consumer, and Rare goods from the output of Market.json.
So, as per the schema, do include it if available.

Key Renames

Many of the key names have a different case defined in this schema, make sure you are renaming them as appropriate.

StarSystem to systemName

Rename the StarSystem key name to systemName.

Elisions

Remove _Localised key/values

All keys whose name ends with _Localised, i.e. the Name_Localised key/values in Items.

Other Elisions

You MUST remove the following key/value pairs from the data:

• StationType key/value.
• Producer key/value pair in Items.
• Rare key/value pair in Items.
• id key/value pair in Items.

In the list of commodites:

• Skip commodities with "categoryname": "NonMarketable" (i.e. Limpets - not purchasable in station market) or a non-empty"legality": string (not normally traded at this station market).

Item Category

Remove not only the Category_Localised key/value, as above, but also the Category key/value pair from each Item.

Augmentations

horizons flag

You SHOULD add this key/value pair, using the value from the LoadGame event.

odyssey flag

You SHOULD add this key/value pair, using the value from the LoadGame event.

Using CAPI data

It is not recommended to use CAPI data as the source as it's fraught with additional issues. EDMarketConnector does so in order to facilitate obtaining data without the player needing to open the commodities screen.

Please read the guidance on checking for CAPI lag before utilising CAPI data for EDDN messages.

Note that CAPI /market data will sometimes have the StatusFlasg per item, which are defined as optional in this schema (because they're not in the Market.json data). You SHOULD include this data in your message if using CAPI as the source.

Now you will need to construct the necessary additional fields:

CAPI horizons flag

If your application can be certain that the game client is still running, and logged into the game (not just run to the main menu), then you can simply use the value from the LoadGame journal event.

Otherwise, you MUST check if any of the economies from the /market data have a name of Colony, if so, set this flag true.

Additionally, you should retrieve the CAPI /shipyard endpoint and check if any of the listed ships or modules have a sku value of ELITE_HORIZONS_V_PLANETARY_LANDINGS. If so, set this flag true.

CAPI odyssey flag

Unfortunately there is no method to be certain of this from CAPI data, so you will have to trust in the system/station name check and use the value from the Journal LoadGame event.