# Add a Ledger Entry

This endpoint adds one or multiple Entries to a Ledger. You can add Entries:

  • To your personal Ledger.
  • Based on the account UUID if the Twin rule allows you to perform operations on the given Twin.
Method Path Operation*
POST /twins/{twin}/ledgers/personal add_twin_ledger_entry
POST /twins/{twin}/ledgers/{ledger} add_twin_ledger_entry

*

In order for a user to perform the "add_twin_ledger_entry" operation, the "add_twin_ledger_entry" permission must be included in the list of allowed actions in the statement of the user's role.

# Request

Parameter Type In Description
twin
required
string path Twin UUID.
ledger
required*
string path Ledger UUID.
entries
required
dictionary body Key-value pairs:
- Key: alphanumeric string unique within the Ledger. It must match the regular expression (opens new window). ^[a-z_][0-9a-z_]{0,127}$.
- Value: Valid JSON data type.

*

The "ledger" parameter is required in the path of the request for requests based on the account UUID if the Twin rule allows you to perform operations on the given Twin.

# Value type Entry parameters

Parameter Type In Description
value
required*
valid JSON data type body User-defined value of the Entry. This field cannot be changed by the user for reference type Entries and include type Entries.
visibility
optional**
string, DEFAULT=null body Visibility of the Entry. If the "visibility" of an Entry is null, the Entry is private. Private Entries are only visible to users of the account that owns the Ledger. If all Entries of the Ledger are private, the Ledger is private. If the "visibility" of an Entry is not null, the Entry is public. Public Entries are visible to users of the account that owns the Ledger and also visible to users of other accounts if the visibility rule evaluates to True. If any of the Entries of the Ledger is public, the Ledger is public.
history
optional***
string body Time for which the history of changes of the Entry's value is to be stored. Please note that the limit of stored History records is 1000 per Entry. If there are more than 1000 Entry value changes within the specified time period, only 1000 most recent History records will be stored. The "history" value must match the regular expression (opens new window).^([1-9][0-9]{0,2}[DWMY])|(INF)$.
If there is no "history" attribute, the History service is not enabled
If "history" is set to null, the History service is not enabled
If "history" is set to "INF", the most recent 1000 historical Entry values are stored for the Entry.
If "history" is set to a time period (e.g., days, weeks, months), the historical Entry values are stored for the given time period subject to the maximum number of history records limit (1000 per Entry).
timeseries
optional****
dictionary body
Timeseries attribute. It holds the name of the Timeseries table, the "measurement" attribute, and (optionally) the "dimensions" attribute.
Attribute Type In Description
measurement string body Name of the measurement column in the given Timeseries table under which the Entry value is to be stored.
dimensions dictionary body Key-value pair:
- Key: name of the dimension under which the Entry value is to be stored.
- Value: Template for the value of the dimension.
publish
optional*****
dictionary body
Holds the details about the Notifications set up for the given Entry.
Attribute Type Description
rule string Notification rule that defines the conditions to be met for a notification to be sent.
topic list List of notification topic templates.

*

The "value" parameter is required for value type Entries. For other Entry types, please see reference type Entry parameters and include type Entry parameters.

**

The "visibility" parameter is optional and does not need to be included in the request body when adding Entries. If it is not included in the request body, its default value (DEFAUL=null) is used.

***

The "history" parameter is optional. If there is no "history" parameter included in the request, the History service is not enabled and historical Entry values are not stored. In case the "history" parameter is included in the request.
If there is no "history" attribute, the History service is not enabled
If "history" is set to null, the History service is not enabled
If "history" is set to "INF", the most recent 1000 historical Entry values are stored for the Entry.
If "history" is set to a time period (e.g., days, weeks, months), the historical Entry values are stored for the given time period subject to the maximum number of history records limit (1000 per Entry).

****

The "timeseries" parameter is optional. If there is no "timeseries" parameter included in the request, Entry value is not stored in the Timeseries database. In order to use the Timeseries service, it needs to be enabled for your account.

*****

The "publish" parameter is optional. If there is no "publish" parameter included in the request, no Notifications are set for a given Entry.

# Reference type Entry parameters

Parameter Type In Description
ref
required*
dictionary body
Reference. It allows to create an Entry based on the "value" field of an Entry in a different Ledger, especially a Ledger of a different account. The value that the reference is pointing to must be visible to the account creating the reference.
Parameter Type In Description
source
required*
string, composed of {twin} (Twin UUID), {ledger} (Ledger UUID)/ Name of the Entry in the Ledger* body Source path to the value that we want the Entry to reference.
*This parameter is required when using the "ref" parameter.
visibility
optional**
string, DEFAULT=null body Visibility of the Entry. If the "visibility" of an Entry is null, the Entry is private. Private Entries are only visible to users of the account that owns the Ledger. If all Entries of the Ledger are private, the Ledger is private. If the "visibility" of an Entry is not null, the Entry is public. Public Entries are visible to users of the account that owns the Ledger and also visible to users of other accounts if the visibility rule evaluates to True. If any of the Entries of the Ledger is public, the Ledger is public.
history
optional***
string body Time for which the history of changes of the Entry's value is to be stored. Please note that the limit of stored History records is 1000 per Entry. If there are more than 1000 Entry value changes within the specified time period, only 1000 most recent History records will be stored. The "history" value must match the regular expression (opens new window).^([1-9][0-9]{0,2}[DWMY])|(INF)$.
If there is no "history" attribute, the History service is not enabled
If "history" is set to null, the History service is not enabled
If "history" is set to "INF", the most recent 1000 historical Entry values are stored for the Entry.
If "history" is set to a time period (e.g., days, weeks, months), the historical Entry values are stored for the given time period subject to the maximum number of history records limit (1000 per Entry).
timeseries
optional****
dictionary body
Timeseries attribute. It holds the name of the Timeseries table, the "measurement" attribute, and (optionally) the "dimensions" attribute.
Attribute Type In Description
measurement string body Name of the measurement column in the given Timeseries table under which the Entry value is to be stored.
dimensions dictionary body Key-value pair:
- Key: name of the dimension under which the Entry value is to be stored.
- Value: Template for the value of the dimension.
publish
optional*****
dictionary body
Holds the details about the Notifications set up for the given Entry.
Attribute Type Description
rule string Notification rule that defines the conditions to be met for a notification to be sent
topic list List of notification topic templates

*

The "ref" parameter is required for reference type Entries. For other Entry types, please see value type Entry parameters and include type Entry parameters.

**

The "visibility" parameter is optional and does not need to be included in the request body when adding Entries. If it is not included in the request body, its default value (DEFAUL=null) is used.

***

The "history" parameter is optional. If there is no "history" parameter included in the request, the History service is not enabled and historical Entry values are not stored. In case the "history" parameter is included in the request.
If "history" is set to "INF", the most recent 1000 historical Entry values are stored for the Entry.
If "history" is set to a time period (e.g., days, weeks, months), the historical Entry values are stored for the given time period subject to the maximum number of history records limit (1000 per Entry) .

****

The "timeseries" parameter is optional. If there is no "timeseries" parameter included in the request, Entry value is not stored in the Timeseries database. In order to use the Timeseries service, it needs to be enabled for your account.

*****

The "publish" parameter is optional. If there is no "publish" parameter included in the request, no Notifications are set for a given Entry.

# Include type Entry parameters

Parameter Type In Description
include
optional*
string body Entry is an external const-like value fetched upon request.

*

The "include" parameter is required for include type Entries. For other Entry types, please see value type Entry parameters and reference type Entry parameters.

# Response

Attribute Type Description
entry_created_ts timestamp Last time when an Entry in the Ledger was created. Measured in seconds (to three decimal places) that have elapsed since the Unix epoch (opens new window).
entry_updated_ts timestamp Last time when an Entry in the Ledger was updated. Measured in seconds (to three decimal places) that have elapsed since the Unix epoch (opens new window).
value_changed_ts timestamp Last time when a value of an Entry in the Ledger was changed. Measured in seconds (to three decimal places) that have elapsed since the Unix epoch (opens new window).
entries dictionary Key-value pairs:
- Key: alphanumeric string unique within the Ledger. It must match the regular expression (opens new window). ^[a-z_][0-9a-z_]{0,127}$.
- Value: JSON compliant object.
indexes* list of strings List of names of Indexes tables. An Indexes table is listed if the Ledger meets the conditions of the Indexes table and is in the Indexes table. Indexes are not removed automatically from Entries when an Indexes table is truncated. After an Indexes table has been truncated, indexes will only be removed through automated system update such as updating a Ledger Entry.

*

The Indexes service needs to be enabled for your account. Please contact hello@trustedtwin.com for more details.

# Entry attributes

Attribute Type Description
entry_created_ts timestamp Time at which the Entry was created. Measured in seconds (to three decimal places) that have elapsed since the Unix epoch (opens new window).
entry_updated_ts timestamp Time at which the Entry was last updated. Measured in seconds (to three decimal places) that have elapsed since the Unix epoch (opens new window).
value_changed_ts timestamp Time at which the value of an Entry was last changed. Measured in seconds (to three decimal places) that have elapsed since the Unix epoch (opens new window).
value string User-defined value of the Entry. This field cannot be changed by the user if the "ref" (reference) field exists.
visibility string Visibility of the Entry. If the "visibility" of an Entry is null, the Entry is private. Private Entries are only visible to users of the account that owns the Ledger. If all Entries of the Ledger are private, the Ledger is private. If the "visibility" of an Entry is not null, the Entry is public. Public Entries are visible to users of the account that owns the Ledger and also visible to users of other accounts if the visibility rule evaluates to True. If any of the Entries of the Ledger is public, the Ledger is public.
ref* dictionary
Reference. It allows to create an Entry based on the "value" field of an Entry in a different Ledger, especially a Ledger of a different account. The value that the reference is pointing to must be visible to the account creating the reference.
Attribute Type Description
source string, composed of {twin} (Twin UUID), {ledger} (Ledger UUID)/ Name of the Entry in the Ledger* Source path to the value that we want the Entry to reference.
status enum, value is "not_found" or "ok" Status of the reference. It can have one of the following values:
- "not_found": The value could not be found. "not_found" is the default value until the value in the Entry that the reference is pointing to is first updated. It can also mean that the value is set to null as the Entry that the reference is pointing to does not exist or is not accessible to the account, because there is a circular reference or because there are too many transfers between references (the maximum number of hops allowed is 32).
- "ok": The Entry value is consistent with the value that the reference is pointing to.
include** string Entry is an external const-like value fetched upon request.
history string Time for which the history of changes of the Entry's value is to be stored. Please note that the limit of stored History records is 1000 per Entry. If there are more than 1000 Entry value changes within the specified time period, only 1000 most recent History records will be stored. The "history" value must match the regular expression (opens new window).^([1-9][0-9]{0,2}[DWMY])|(INF)$.
If there is no "history" attribute, the History service is not enabled
If "history" is set to null, the History service is not enabled
If "history" is set to "INF", the most recent 1000 historical Entry values are stored for the Entry.
If "history" is set to a time period (e.g., days, weeks, months), the historical Entry values are stored for the given time period subject to the maximum number of history records limit (1000 per Entry).
timeseries*** dictionary
Timeseries attribute. It holds the name of the Timeseries table, the "measurement" attribute, and (optionally) the "dimensions" attribute.
Attribute Type Description
measurement string Name of the measurement column in the given Timeseries table under which the Entry value is to be stored.
dimensions dictionary Key-value pair:
- Key: name of the dimension under which the Entry value is to be stored.
- Value: Template for the value of the dimension.
publish dictionary
Holds the details about the Notifications set up for the given Entry.
Attribute Type Description
rule string Notification rule that defines the conditions to be met for a notification to be sent
topic list List of notification topic templates

*

The "ref" attribute is only returned for reference type Entries.

**

The "include" attribute is only returned for include type Entries.

***

The Timeseries service needs to be enabled for your account. Please contact hello@trustedtwin.com for more details.

IMPORTANT NOTE

Please note that once you create an Entry where the "value" is picked up through a "reference" from another Entry, you cannot update the Entry so that it does not contain a "reference". In such case, you would need to delete the Entry and create a new Entry without the "reference" field.

# Response ('Entry already exists')

NOTE

If you try to add an Entry that already exists, you will receive the message "error": "Entry already exists." for this Entry in the response. However, the response itself will return the 201 Created status code. Please see the below example for more details.

In the example below, we create two Entries - the Entry "krakow" which does not exist in the Ledger yet and the Entry "wroclaw" which already exists in the Ledger.

NOTE

The templates follow the Python string format() convention (see Format String Syntax (opens new window)). Therefore, you can use variables in the templates (see Timeseries introduction section for a list of available variables). In our example we use the entry_name variable. As a result, the Entry values will be tagged with a dimension which is equal to the name of the Entry (in our example it is"wroclaw").

The response returns the details of the created Entry "krakow" and the message "error": "Entry already exists" for the Entry "wroclaw" which already exists in the Ledger. The status code of the response is 201 Created.

# Status codes

Requests to this endpoint result in generic status codes. For a comprehensive list of status codes, please consult the Status Codes section.

Status code Message Comment
201 Created If an Entry that you are trying to create already exists, you will receive the error: "error": "Entry already exists." for this Entry in the response.