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homechevron_rightDocschevron_rightAPI Referencechevron_rightNotecard APIchevron_rightnote Requests - API Reference

note Requests

The note requests enable the quick creation and management of Notes in Notefiles.

The requests in this section are available on the Notecard API. Consult the Notehub Device API to manage inbound and DB Notefiles from Notehub.

Notecard Firmware Version:
Latest (9.x)
Latest (9.x)8.x LTS7.x6.x LTS5.x4.x LTS3.x2.x LTS

note.add CellCell+WiFiLoRaWiFi

Adds a Note to a Notefile, creating the Notefile if it doesn't yet exist.

If a Notefile name is specified, the file must either be a DB Notefile or outbound queue file (see file argument below).

Arguments

file

string (Default: data.qo)

The name of the Notefile.

On Notecard LoRa this argument is required. On all other Notecards this field is optional and defaults to data.qo if not provided.

When using this request on the Notecard the Notefile name must end in one of:

.qo for a queue outgoing (Notecard to Notehub) with plaintext transport

.qos for a queue outgoing with encrypted transport

.db for a bidirectionally synchronized database with plaintext transport

.dbs for a bidirectionally synchronized database with encrypted transport

.dbx for a local-only database

note

string (optional)

If the Notefile has a .db/.dbs/.dbx extension, specifies a unique Note ID.

If note string is "?", then a random unique Note ID is generated and returned as {"note":"xxx"}.

If this argument is provided for a .qo Notefile, an error is returned.

body

JSON object (optional)

A JSON object to be enqueued. A note must have either a body or a payload, and can have both.

payload

base64 string (optional)

A base64-encoded binary payload. A note must have either a body or a payload, and can have both. If a Note template is not in use, payloads are limited to 250 bytes.

sync

boolean (optional)

Set to true to sync immediately. Only applies to outgoing Notecard requests, and only guarantees syncing the specified Notefile. Auto-syncing incoming Notes from Notehub is set on the Notecard with {"req": "hub.set", "mode":"continuous", "sync": true}.

key

string (optional)

The name of an environment variable in your Notehub.io project that contains the contents of a public key. Used when encrypting the Note body for transport.

verify

boolean (optional)

If set to true and using a templated Notefile, the Notefile will be written to flash immediately, rather than being cached in RAM and written to flash later.

binary

boolean (optional)

If true, the Notecard will send all the data in the binary buffer to Notehub.

Learn more in this guide on Sending and Receiving Large Binary Objects.

live

boolean (optional)

If true, bypasses saving the Note to flash on the Notecard. Required to be set to true if also using "binary":true.

full

boolean (optional)

If set to true, and the Note is using a Notefile Template, the Note will bypass usage of omitempty and retain null, 0, false, and empty string "" values.

limit

boolean (optional)

If set to true, the Note will not be created if Notecard is in a penalty box.

{
  "req": "note.add",
  "file": "sensors.qo",
  "body": { "temp": 72.22 },
  "sync": true
}
J *req = NoteNewRequest("note.add");
JAddStringToObject(req, "file", "sensors.qo");
JAddBoolToObject(req, "sync", true);

J *body = JCreateObject();
JAddNumberToObject(body, "temp", 72.22);
JAddItemToObject(req, "body", body);

NoteRequest(req);
req = {"req": "note.add"}
req["file"] = "sensors.qo"
req["body"] = {"temp": 72.22 }
req["sync"] = True
rsp = card.Transaction(req)
Response Members

total

The total number of Notes in the Notefile.

template

true when a template is active on the Notefile.

Example Response
{ "total": 12 }
More information:
  • Encrypting and Decrypting Data with the Notecard

note.changes CellCell+WiFiWiFi

Used to incrementally retrieve changes within a specific Notefile.

Arguments

file

string

The Notefile ID.

tracker

string (optional)

The change tracker ID. This value is developer-defined and can be used across both the note.changes and file.changes requests.

max

integer (optional)

The maximum number of Notes to return in the request.

start

boolean (optional)

true to reset the tracker to the beginning.

stop

boolean (optional)

true to delete the tracker.

deleted

boolean (optional)

true to return deleted Notes with this request. Deleted notes are only persisted in a database notefile (.db/.dbs) between the time of note deletion on the Notecard and the time that a sync with notehub takes place. As such, this boolean will have no effect after a sync or on queue notefiles (.q*).

delete

boolean (optional)

true to delete the Notes returned by the request.

reset

boolean (optional)

true to reset a change tracker.

{
  "req": "note.changes",
  "file": "my-settings.db",
  "tracker": "inbound-tracker",
  "start": true
}
J *req = NoteNewRequest("note.changes");
JAddStringToObject(req, "file", "my-settings.db");
JAddStringToObject(req, "tracker", "inbound-tracker");
JAddBoolToObject(req, "start", true);

NoteRequest(req);
req = {"req": "note.changes"}
req["file"] = "my-settings.db"
req["tracker"] = "inbound-tracker"
req["start"] = True
rsp = card.Transaction(req)
{
  "req": "note.changes",
  "file": "my-settings.db",
  "tracker": "inbound-tracker",
  "start": true,
  "delete": true,
  "max": 2
}
J *req = NoteNewRequest("note.changes");
JAddStringToObject(req, "file", "my-settings.db");
JAddStringToObject(req, "tracker", "inbound-tracker");
JAddBoolToObject(req, "start", true);
JAddBoolToObject(req, "delete", true);
JAddNumberToObject(req, "max", 2);

NoteRequest(req);
req = {"req": "note.changes"}
req["file"] = "my-settings.db"
req["tracker"] = "inbound-tracker"
req["start"] = True
req["delete"] = True
req["max"] = 2
rsp = card.Transaction(req)
Response Members

total

integer

The total number of Notes in the Notefile.

changes

integer

The number of pending changes in the Notefile.

notes

JSON object

An object with a key for each Note (the Note ID in a DB Notefile or an internally-generated ID for .qo and .qi Notes) and value object with the body of each Note and the time the Note was added.

Example Response
{
  "changes": 4,
  "total": 4,
  "notes": {
    "setting-one": { "body": { "foo": "bar" }, "time": 1598918235 },
    "setting-two": { "body": { "foo": "bat" }, "time": 1598918245 },
    "setting-three": { "body": { "foo": "baz" }, "time": 1598918225 },
    "setting-four": { "body": { "foo": "foo" }, "time": 1598910532 }
  }
}
More information:
  • Using Change Trackers With Inbound Data

note.delete CellCell+WiFiLoRaWiFi

Deletes a Note from a DB Notefile by its Note ID. To delete Notes from a .qi Notefile, use note.get or note.changes with delete:true.

Arguments

file

string

The Notefile from which to delete a Note. Must be a Notefile with a .db or .dbx extension.

note

string

The Note ID of the Note to delete.

verify

boolean (optional)

If set to true and using a templated Notefile, the Notefile will be written to flash immediately, rather than being cached in RAM and written to flash later.

{
  "req": "note.delete",
  "file": "my-settings.db",
  "note": "measurements"
}
J *req = NoteNewRequest("note.delete");
JAddStringToObject(req, "file", "my-settings.db");
JAddStringToObject(req, "note", "measurements");

NoteRequest(req);
req = {"req": "note.delete"}
req["file"] = "my-settings.db"
req["note"] = "measurements"
card.Transaction(req)
Response Members
None: an empty object {} means success.

note.get CellCell+WiFiLoRaWiFi

Retrieves a Note from a Notefile. The file must either be a DB Notefile or inbound queue file (see file argument below).

.qo/.qos Notes must be read from the Notehub event table using the Notehub Event API.

Arguments

file

string (Default: data.qi)

The Notefile name must end in .qi (for plaintext transport), .qis (for encrypted transport), .db or .dbx (for local-only DB Notefiles).

note

string (optional)

If the Notefile has a .db or .dbx extension, specifies a unique Note ID. Not applicable to .qi Notefiles.

delete

boolean (optional)

true to delete the Note after retrieving it.

deleted

boolean (optional)

true to allow retrieval of a deleted Note.

decrypt

boolean (optional)

true to decrypt encrypted inbound Notefiles.

{
  "req": "note.get",
  "file": "requests.qi",
  "delete": true
}
J *req = NoteNewRequest("note.get");
JAddStringToObject(req, "file", "requests.qi");
JAddBoolToObject(req, "delete", true);

NoteRequest(req);
req = {"req": "note.get"}
req["file"] = "requests.qi"
req["delete"] = True
rsp = card.Transaction(req)
{
  "req": "note.get",
  "file": "my-settings.db",
  "note": "measurements"
}
J *req = NoteNewRequest("note.get");
JAddStringToObject(req, "file", "my-settings.db");
JAddStringToObject(req, "note", "measurements");

NoteRequest(req);
req = {"req": "note.get"}
req["file"] = "my-settings.db"
req["note"] = "measurements"
rsp = card.Transaction(req)
Response Members

body

JSON object

The JSON body, if contained in the Note.

payload

base64 string

The payload, if contained in the Note.

time

UNIX Epoch time

The time the Note was added to the Notecard or Notehub.

Example Response
{
  "body": {
    "api-key1": "api-val1"
  },
  "time": 1598909219
}

note.update CellCell+WiFiLoRaWiFi

Updates a Note in a DB Notefile by its ID, replacing the existing body and/or payload.

Arguments

file

string

The name of the DB Notefile that contains the Note to update.

note

string

The unique Note ID.

body

JSON object

A JSON object to add to the Note. A Note must have either a body or payload, and can have both.

payload

base64 string

A base64-encoded binary payload. A Note must have either a body or payload, and can have both.

verify

boolean (optional)

If set to true and using a templated Notefile, the Notefile will be written to flash immediately, rather than being cached in RAM and written to flash later.

{
  "req": "note.update",
  "file": "my-settings.db",
  "note": "measurements",
  "body": { "interval": 60 }
}
J *req = NoteNewRequest("note.update");
JAddStringToObject(req, "file", "my-settings.db");
JAddStringToObject(req, "note", "measurements");

J *body = JCreateObject();
JAddNumberToObject(body, "interval", 60);
JAddItemToObject(req, "body", body);

NoteRequest(req);
req = {"req": "note.update"}
req["file"] = "my-settings.db"
req["note"] = "measurements"
req["body"] = {"interval": 60 }
card.Transaction(req)
Response Members
None: an empty object {} means success.

note.template CellCell+WiFiLoRaWiFi

By using the note.template request with any .qo/.qos Notefile, developers can provide the Notecard with a schema of sorts to apply to future Notes added to the Notefile. This template acts as a hint to the Notecard that allows it to internally store data as fixed-length binary records rather than as flexible JSON objects which require much more memory. Using templated Notes in place of regular Notes increases the storage and sync capability of the Notecard by an order of magnitude.

Read about Working with Note Templates for additional information.

See examples of note.template usage in these accelerator projects.

Arguments

file

string

The name of the Notefile to which the template will be applied.

body

JSON object (optional)

A sample JSON body that specifies field names and values as "hints" for the data type. Possible data types are: boolean, integer, float, and string. See Understanding Template Data Types for an explanation of type hints and explanations.

length

integer (optional)

The maximum length of a payload (in bytes) that can be sent in Notes for the template Notefile. As of v3.2.1 length is not required, and payloads can be added to any template-based Note without specifying the payload length.

verify

boolean (optional)

If true, returns the current template set on a given Notefile.

format

string (optional)

By default all Note templates automatically include metadata, including a timestamp for when the Note was created, various fields about a device's location, as well as a timestamp for when the device's location was determined.

By providing a format of "compact" you tell the Notecard to omit this additional metadata to save on storage and bandwidth. The use of format: "compact" is required for Notecard LoRa and a Notecard paired with Starnote.

When using "compact" templates, you may include the following keywords in your template to add in fields that would otherwise be omitted: _lat, _lon, _ltime, _time. See Creating Compact Templates to learn more.

port

integer

This argument is required on Notecard LoRa and a Notecard paired with Starnote, but ignored on all other Notecards.

A port is a unique integer in the range 1–100, where each unique number represents one Notefile. This argument allows the Notecard to send a numerical reference to the Notefile over the air, rather than the full Notefile name.

The port you provide is also used in the “frame port” field on LoRaWAN gateways.

delete

boolean

Set to true to delete all pending Notes using the template if one of the following scenarios is also true:

Connecting via non-NTN (e.g. cellular or Wi-Fi) communications, but attempting to sync NTN-compatible Notefiles.

or

Connecting via NTN (e.g. satellite) communications, but attempting to sync non-NTN-compatible Notefiles.

Read more about this feature in Starnote Best Practices.

{
  "req": "note.template",
  "file": "readings.qo",
  "body": {
    "new_vals": true,
    "temperature": 14.1,
    "humidity": 11,
    "pump_state": "4"
  }
}
J *req = NoteNewRequest("note.template");
JAddStringToObject(req, "file", "readings.qo");

J *body = JCreateObject();
JAddBoolToObject(body, "new_vals", true);
JAddNumberToObject(body, "temperature", 14.1);
JAddNumberToObject(body, "humidity", 11);
JAddStringToObject(body, "pump_state", "4");
JAddItemToObject(req, "body", body);

NoteRequest(req);
req = {"req": "note.template"}
req["file"] = "readings.qo"
req["body"] = {
    "new_vals": True,
    "temperature": 14.1,
    "humidity": 11,
    "pump_state": "4"
  }
rsp = card.Transaction(req)
{
  "req": "note.template",
  "file": "readings.qo",
  "body": {
    "new_vals": true,
    "temperature": 14.1,
    "humidity": 11,
    "pump_state": "4"
  },
  "format": "compact",
  "port": 50
}
J *req = NoteNewRequest("note.template");
JAddStringToObject(req, "file", "readings.qo");

J *body = JCreateObject();
JAddBoolToObject(body, "new_vals", true);
JAddNumberToObject(body, "temperature", 14.1);
JAddNumberToObject(body, "humidity", 11);
JAddStringToObject(body, "pump_state", "4");
JAddItemToObject(req, "body", body);

JAddStringToObject(req, "format", "compact");
JAddNumberToObject(req, "port", 50);

NoteRequest(req);
req = {"req": "note.template"}
req["file"] = "readings.qo"

req["body"] = {
  "new_vals": True,
  "temperature": 14.1,
  "humidity": 11,
  "pump_state": "4"
}

req["format"] = "compact"
req["port"] = 50

rsp = card.Transaction(req)
{
  "req": "note.template",
  "file": "readings.qo",
  "body": {
    "temperature": 14.1,
    "_lat": 14.1,
    "_lon": 14.1,
    "_ltime": 14,
    "_time": 14
  },
  "format": "compact",
  "port": 50
}
J *req = NoteNewRequest("note.template");
JAddStringToObject(req, "file", "readings.qo");

J *body = JCreateObject();
JAddNumberToObject(body, "temperature", 14.1);
JAddNumberToObject(body, "_lat", 14.1);
JAddNumberToObject(body, "_lon", 14.1);
JAddNumberToObject(body, "_ltime", 14);
JAddNumberToObject(body, "_time", 14);
JAddItemToObject(req, "body", body);

JAddStringToObject(req, "format", "compact");
JAddNumberToObject(req, "port", 50);

NoteRequest(req);
req = {"req": "note.template"}
req["file"] = "readings.qo"
req["format"] = "compact"
req["port"] = 50
req["body"] = {
  "new_vals": True,
  "temperature": 14.1,
  "_lat": 14.1,
  "_lon": 14.1,
  "_ltime": 14,
  "_time": 14
}
rsp = card.Transaction(req)
{
  "req":    "note.template",
  "file":   "readings.qo",
  "verify": true
}
J *req = NoteNewRequest("note.template");
JAddStringToObject(req, "file", "readings.qo");
JAddBoolToObject(req, "verify", true);

NoteRequest(req);
req = {"req": "note.template"}
req["file"] = "readings.qo"
req["verify"] = True
rsp = card.Transaction(req)
Response Members

bytes

integer

The number of bytes that will be transmitted to Notehub, per Note, before compression.

template

boolean

true if an active template exists on the Notefile.

body

If the verify argument is provided and the Notefile has an active template, the template body

length

If the verify argument is provided and the Notefile has an active template with a payload, the payload length.

format

If the format argument is provided, this represents the format applied to the template.

Example Response
{
  "bytes": 40
}
More information:
  • Working With Note Templates
  • Understanding Template Data Types
  • Accelerator Apps that use note.template
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