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Python client documentation

This documentation is for developers interested in using the GOV.UK Notify Python client to send emails, text messages or letters. Notify supports Python 3.8 and higher.

Set up the client

Install the client

Run the following code in the command line:

pip install notifications-python-client

Refer to the client changelog for the client version number and the latest updates.

Create a new instance of the client

Add this code to your application:

from notifications_python_client.notifications import NotificationsAPIClient

notifications_client = NotificationsAPIClient(api_key)

Arguments

api_key (required)

To get an API key, sign in to GOV.UK Notify and go to the API integration page. You can find more information in the API keys section of this documentation.

timeout (optional)

The default timeout is 30 seconds. For more information about timeouts see https://docs.python-requests.org/en/latest/user/advanced/#timeouts.

Send a message

You can use GOV.UK Notify to send emails, text messages and letters.

Send a text message

Method

response = notifications_client.send_sms_notification(
    phone_number='+447900900123', # required string
    template_id='f33517ff-2a88-4f6e-b855-c550268ce08a', # required UUID string
)

Arguments

phone_number (required)

The phone number of the recipient of the text message. This can be a UK or international number.

template_id (required)

To find the template ID:

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant template.
  3. Select Copy template ID to clipboard.
personalisation (optional)

If a template has placeholder fields for personalised information such as name or reference number, you must provide their values in a dictionary with key value pairs. For example:

personalisation={
    'first_name': 'Amala',
    'application_date': '2018-01-01',
}

You can leave out this argument if a template does not have any placeholder fields for personalised information.

reference (optional)

A unique identifier you can create if necessary. This reference identifies a single unique message or a batch of messages. It must not contain any personal information such as name or postal address. For example:

reference='STRING', # optional string - identifies notification(s)

You can leave out this argument if you do not have a reference.

sms_sender_id (optional)

A unique identifier of the sender of the text message.

To find the text message sender:

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Text Messages section, select Manage on the Text Message sender row.

You can then either:

  • copy the sender ID that you want to use and paste it into the method
  • select Change to change the default sender that the service will use, and select Save
sms_sender_id='8e222534-7f05-4972-86e3-17c5d9f894e2' # optional UUID string

You can leave out this argument if your service only has one text message sender, or if you want to use the default sender.

Response

If the request to the client is successful, the client returns a dict:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "STRING",
  "content": {
    "body": "MESSAGE TEXT",
    "from_number": "SENDER"
  },
  "uri": "https://api.notifications.service.gov.uk/v2/notifications/740e5834-3a29-46b4-9a6f-16142fde533a",
  "template": {
    "id": 'f33517ff-2a88-4f6e-b855-c550268ce08a',
    "version": INTEGER,
    "uri": "https://api.notifications.service.gov.uk/v2/template/ceb50d92-100d-4b8b-b559-14fa3b091cd"
  }
}

If you are using the test API key, all your messages will come back with a delivered status.

All messages sent using the team and guest list or live keys will appear on your dashboard.

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code.

error.status_code error.message How to fix
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient using a team-only API key"
}] 		Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}] 		Your service cannot send this text message in trial mode
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type TEAM/TEST/LIVE of 3000 requests per 60 seconds"
}] 		Refer to API rate limits for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (LIMIT NUMBER) for today"
}] 		Refer to service limits for the limit number
500 [{
"error": "Exception",
"message": "Internal server error"
}] 		Notify was unable to process the request, resend your text message.

Send an email

Method

response = notifications_client.send_email_notification(
    email_address='sender@something.com', # required string
    template_id='f33517ff-2a88-4f6e-b855-c550268ce08a', # required UUID string
)

Arguments

email_address (required)

The email address of the recipient.

template_id (required)

To find the template ID:

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant template.
  3. Select Copy template ID to clipboard.
personalisation (optional)

If a template has placeholder fields for personalised information such as name or reference number, you need to provide their values in a dictionary with key value pairs. For example:

personalisation={
    "first_name": "Amala",
    "application_date": "2018-01-01",
    # pass in a list and it will appear as bullet points in the message:
    "required_documents": ["passport", "utility bill", "other id"],
}

You can leave out this argument if a template does not have any placeholder fields for personalised information.

reference (optional)

A unique identifier you can create if necessary. This reference identifies a single unique email or a batch of emails. It must not contain any personal information such as name or postal address. For example:

reference='STRING', # optional string - identifies notification(s)

You can leave out this argument if you do not have a reference.

If you send subscription emails you must let recipients opt out of receiving them. Read our Using Notify page for more information about unsubscribe links.

The one-click unsubscribe URL will be added to the headers of your email. Email clients will use it to add an unsubscribe button.

one_click_unsubscribe_url = 'https://example.com/unsubscribe.html?opaque=123456789'

The one-click unsubscribe URL must respond to an empty POST request by unsubscribing the user from your emails. You can include query parameters to help you identify the user.

Your unsubscribe URL and response must comply with the guidance specified in Section 3.1 of IETF RFC 8058.

You can leave out this argument if the email being sent is not a subscription email.

To add an unsubscribe link at the bottom of your email, use square brackets around the link text and round brackets around the URL. Make sure there are no spaces between the brackets or the link will not work.

Use this example if you have a webpage for users to manage their email subscriptions:

[Unsubscribe](https://www.example.gov.uk/unsubscribe)

Your webpage should ask the recipients to confirm that they want to unsubscribe.

If you do not have your own webpage, you can add a ‘mailto’ link to let users send an email to your team instead. For example:

[Unsubscribe](mailto:example@gov.uk?subject=unsubscribe)

The email address should be a shared inbox managed by your team, not your own email address.

email_reply_to_id (optional)

This is an email address specified by you to receive replies from your users. You must add at least one reply-to email address before your service can go live.

To add a reply-to email address:

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Email section, select Manage on the Reply-to email addresses row.
  4. Select Add reply-to address.
  5. Enter the email address you want to use, and select Add.

For example:

email_reply_to_id='8e222534-7f05-4972-86e3-17c5d9f894e2' # optional UUID string

You can leave out this argument if your service only has one reply-to email address, or you want to use the default email address.

Send a file by email

To send a file by email, add a placeholder to the template then upload a file. The placeholder will contain a secure link to download the file.

The links are unique and unguessable. GOV.UK Notify cannot access or decrypt your file.

Your file will be available to download for a default period of 26 weeks (6 months).

To help protect your files you can also:

  • ask recipients to confirm their email address before downloading
  • choose the length of time that a file is available to download

Add contact details to the file download page

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Email section, select Manage on the Send files by email row.
  4. Enter the contact details you want to use, and select Save.

Add a placeholder to the template

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant email template.
  3. Select Edit.
  4. Add a placeholder to the email template using double brackets. For example: “Download your file at: ((link_to_file))”

Your email should also tell recipients how long the file will be available to download.

Upload your file

You can upload the following file types:

  • CSV (.csv)
  • image (.jpeg, .jpg, .png)
  • Microsoft Excel Spreadsheet (.xlsx)
  • Microsoft Word Document (.doc, .docx)
  • PDF (.pdf)
  • text (.json, .odt, .rtf, .txt)

Your file must be smaller than 2MB. Contact the GOV.UK Notify team if you need to send other file types.

Pass the file object as a value into the personalisation argument. For example:

from notifications_python_client import prepare_upload

with open('file.pdf', 'rb') as f:
    ...
    personalisation={
      'first_name': 'Amala',
      'application_date': '2018-01-01',
      'link_to_file': prepare_upload(f),
    }

Set the filename

To do this you will need version 9.0.0 of the Python client library, or a more recent version.

You should provide a filename when you upload your file.

The filename should tell the recipient what the file contains. A memorable filename can help the recipient to find the file again later.

The filename must end with a file extension. For example, .csv for a CSV file. If you include the wrong file extension, recipients may not be able to open your file.

If you do not provide a filename for your file, Notify will:

  • generate a random filename
  • try to add the correct file extension

If Notify cannot add the correct file extension, recipients may not be able to open your file.

from notifications_python_client import prepare_upload

with open('file.csv', 'rb') as f:
    ...
    personalisation={
      'first_name': 'Amala',
      'application_date': '2018-01-01',
      'link_to_file': prepare_upload(f, filename='2023-12-25-daily-report.csv'),
    }

Ask recipients to confirm their email address before they can download the file

When a recipient clicks the link in the email you’ve sent them, they have to enter their email address. Only someone who knows the recipient’s email address can download the file.

This security feature is turned on by default.

If you do not want to use this feature, you can turn it off on a file-by-file basis.

To do this you will need version 6.4.0 of the Python client library, or a more recent version.

You should not turn this feature off if you send files that contain:

  • personally identifiable information
  • commercially sensitive information
  • information classified as ‘OFFICIAL’ or ‘OFFICIAL-SENSITIVE’ under the Government Security Classifications policy

To let the recipient download the file without confirming their email address, set the confirm_email_before_download flag to False.

from notifications_python_client import prepare_upload

with open('file.pdf', 'rb') as f:
    ...
    personalisation={
      'first_name': 'Amala',
      'application_date': '2018-01-01',
      'link_to_file': prepare_upload(f, confirm_email_before_download=False),
    }

Choose the length of time that a file is available to download

Set the number of weeks you want the file to be available using the retention_period key.

To use this feature will need version 6.4.0 of the Python client library, or a more recent version.

You can choose any value between 1 week and 78 weeks. When deciding this, you should consider:

  • the need to protect the recipient’s personal information
  • whether the recipient will need to download the file again later

If you do not choose a value, the file will be available for the default period of 26 weeks (6 months).

Files sent before 12 April 2023 had a longer default period of 78 weeks (18 months).

from notifications_python_client import prepare_upload

with open('file.pdf', 'rb') as f:
    ...
    personalisation={
      'first_name': 'Amala',
      'application_date': '2018-01-01',
      'link_to_file': prepare_upload(f, retention_period='4 weeks'),
    }

Response

If the request to the client is successful, the client returns a dict:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "STRING",
  "content": {
    "subject": "SUBJECT TEXT",
    "body": "MESSAGE TEXT",
    "from_email": "SENDER EMAIL"
  },
  "uri": "https://api.notifications.service.gov.uk/v2/notifications/740e5834-3a29-46b4-9a6f-16142fde533a",
  "template": {
    "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",
    "version": INTEGER,
    "uri": "https://api.notifications.service.gov.uk/v2/template/f33517ff-2a88-4f6e-b855-c550268ce08a"
  }
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code.

error.status_code error.message How to fix
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient using a team-only API key"
}] 		Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Can't send to this recipient when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}] 		Your service cannot send this email in trial mode
400 [{
"error": "BadRequestError",
"message": "Unsupported file type '(FILE TYPE)'. Supported types are: '(ALLOWED TYPES)'"
}] 		Wrong file type. You can only upload .csv, .doc, .docx, .jpeg, .jpg, .odt, .pdf, .png, .rtf, .txt or .xlsx files
400 [{
"error": "BadRequestError",
"message": "`filename` cannot be longer than 100 characters"
}] 		Choose a shorter filename
400 [{
"error": "BadRequestError",
"message": "`filename` must end with a file extension. For example, filename.csv"
}] 		Include the file extension in your filename
400 [{
"error": "BadRequestError",
"message": "Unsupported value for retention_period '(PERIOD)'. Supported periods are from 1 to 78 weeks."
}] 		Choose a period between 1 and 78 weeks
400 [{
"error": "BadRequestError",
"message": "Unsupported value for confirm_email_before_download: '(VALUE)'. Use a boolean true or false value."
}] 		Use either True or False
400 [{
"error": "BadRequestError",
"message": "File did not pass the virus scan"
}] 		The file contains a virus
400 [{
"error": "BadRequestError",
"message": "Send files by email has not been set up - add contact details for your service at https://www.notifications.service.gov.uk/services/(SERVICE ID)/service-settings/send-files-by-email"
}] 		See how to add contact details to the file download page
400 [{
"error": "BadRequestError",
"message": "Can only send a file by email"
}] 		Make sure you are using an email template
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type TEAM/TEST/LIVE of 3000 requests per 60 seconds"
}] 		Refer to API rate limits for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (LIMIT NUMBER) for today"
}] 		Refer to service limits for the limit number
500 [{
"error": "Exception",
"message": "Internal server error"
}] 		Notify was unable to process the request, resend your email.
- ValueError('File is larger than 2MB') The file is too big. Files must be smaller than 2MB.

Send a letter

When you add a new service it will start in trial mode. You can only send letters when your service is live.

To send Notify a request to go live:

  1. Sign in to GOV.UK Notify.
  2. Go to the Settings page.
  3. In the Your service is in trial mode section, select request to go live.

Method

    response = notifications_client.send_letter_notification(
        template_id='f33517ff-2a88-4f6e-b855-c550268ce08a', # required UUID string
        personalisation={
          'address_line_1': 'The Occupier' # required string,
          'address_line_2': '123 High Street' # required string,
          'address_line_3': 'SW14 6BH' # required string,
        },
    )

Arguments

template_id (required)

To find the template ID:

  1. Sign in to GOV.UK Notify.
  2. Go to the Templates page and select the relevant template.
  3. Select Copy template ID to clipboard.
personalisation (required)

The personalisation argument always contains the following parameters for the letter recipient’s address:

  • address_line_1
  • address_line_2
  • address_line_3
  • address_line_4
  • address_line_5
  • address_line_6
  • address_line_7

The address must have at least 3 lines.

The last line needs to be a real UK postcode or the name of a country outside the UK.

Notify checks for international addresses and will automatically charge you the correct postage.

The postcode personalisation argument has been replaced. If your template still uses postcode, Notify will treat it as the last line of the address.

Any other placeholder fields included in the letter template also count as required parameters. You need to provide their values in a dictionary with key value pairs. For example:

personalisation={
  'address_line_1': 'The Occupier',
  'address_line_2': '123 High Street',
  'address_line_3': 'Richmond upon Thames',
  'address_line_4': 'Middlesex',
  'address_line_5': 'SW14 6BF',
  'name': 'John Smith',
  'application_id': '4134325',
  # pass in a list and it will appear as bullet points in the letter:
  "required_documents": ["passport", "utility bill", "other id"],
}
reference (optional)

A unique identifier you can create if necessary. This reference identifies a single unique letter or a batch of letters. It must not contain any personal information such as name or postal address. For example:

reference='STRING' # optional string - identifies notification(s)

Response

If the request to the client is successful, the client returns a dict:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": 'STRING',
  "content": {
    "subject": "SUBJECT TEXT",
    "body": "LETTER TEXT",
  },
  "uri": "https://api.notifications.service.gov.uk/v2/notifications/740e5834-3a29-46b4-9a6f-16142fde533a",
  "template": {
    "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",
    "version": INTEGER,
    "uri": "https://api.notifications.service.gov.uk/v2/template/f33517ff-2a88-4f6e-b855-c550268ce08a"
  }
  "scheduled_for": None
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code.

error.status_code error.message How to fix
403 [{
"error": "BadRequestError",
"message": "Cannot send letters with a team api key"
}] 		Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Cannot send letters when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}] 		Your service cannot send this letter in trial mode.
400 [{
"error": "ValidationError",
"message": "personalisation address_line_1 is a required property"
}] 		Ensure that your template has a field for the first line of the address, check personalisation for more information.
400 [{
"error": "ValidationError",
"message": "Must be a real UK postcode"
}] 		Ensure that the value for the last line of the address is a real UK postcode.
400 [{
"error": "ValidationError",
"message": "Last line of address must be a real UK postcode or another country"
}] 		Ensure that the value for the last line of the address is a real UK postcode or the name of a country outside the UK.
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock.
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information.
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type TEAM/TEST/LIVE of 3000 requests per 60 seconds"
}] 		Refer to API rate limits for more information.
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (LIMIT NUMBER) for today"
}] 		Refer to service limits for the limit number.
500 [{
"error": "Exception",
"message": "Internal server error"
}] 		Notify was unable to process the request, resend your letter.

Send a precompiled letter

Method

response = notifications_client.send_precompiled_letter_notification(
    reference,      # Reference to identify the notification
    pdf_file,       # PDF File object
    postage         # set postage on your precompiled letter
)

Arguments

reference (required)

A unique identifier you create. This reference identifies a single unique precompiled letter or a batch of precompiled letters. It must not contain any personal information such as name or postal address.

pdf_file (required)

The precompiled letter must be a PDF file which meets the GOV.UK Notify letter specification.

with open("path/to/pdf_file", "rb") as pdf_file:
    notification = notifications_client.send_precompiled_letter_notification(
        reference="your reference", pdf_file=pdf_file
    )
postage (optional)

You can choose first or second class postage for your precompiled letter. Set the value to first for first class, or second for second class. If you do not pass in this argument, the postage will default to second class.

Response

If the request to the client is successful, the client returns a dict:

{
  "id": "740e5834-3a29-46b4-9a6f-16142fde533a",
  "reference": "your-letter-reference",
  "postage": "postage-you-have-set-or-None"
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code.

error.status_code error.message How to fix
403 [{
"error": "BadRequestError",
"message": "Cannot send letters with a team api key"
}] 		Use the correct type of API key
400 [{
"error": "BadRequestError",
"message": "Letter content is not a valid PDF"
}] 		PDF file format is required
400 [{
"error": "BadRequestError",
"message": "Cannot send letters when service is in trial mode - see https://www.notifications.service.gov.uk/trial-mode"
}] 		Your service cannot send this precompiled letter in trial mode
400 [{
"error": "ValidationError",
"message": "reference is a required property"
}] 		Add a reference argument to the method call
400 [{
"error": "ValidationError",
"message": "postage invalid. It must be either first or second."
}] 		Change the value of postage argument in the method call to either ‘first’ or ‘second’
429 [{
"error": "RateLimitError",
"message": "Exceeded rate limit for key type live of 10 requests per 20 seconds"
}] 		Use the correct API key. Refer to API keys for more information
429 [{
"error": "TooManyRequestsError",
"message": "Exceeded send limits (50) for today"
}] 		Refer to service limits for the limit number

Get message status

Get the status of one message

You can only get the status of messages sent within the retention period. The default retention period is 7 days.

Method

response = notifications_client.get_notification_by_id(notification_id)

Arguments

notification_id (required)

The ID of the notification. To find the notification ID, you can either:

Response

If the request to the client is successful, the client will return a dict:

{
    "id": "740e5834-3a29-46b4-9a6f-16142fde533a",  # required string - notification ID
    "reference": "STRING",  # optional string - client reference
    "email_address": "sender@something.com",  # required string for emails
    "phone_number": "+447900900123",  # required string for text messages
    "line_1": "ADDRESS LINE 1",  # required string for letter
    "line_2": "ADDRESS LINE 2",  # required string for letter
    "line_3": "ADDRESS LINE 3",  # required string for letter
    "line_4": "ADDRESS LINE 4",  # optional string for letter
    "line_5": "ADDRESS LINE 5",  # optional string for letter
    "line_6": "ADDRESS LINE 6",  # optional string for letter
    "line_7": "ADDRESS LINE 7", # optional string for letter
    "postage": "first / second / europe / rest-of-world", # required string for letter
    "type": "sms / letter / email",  # required string
    "status": "sending / delivered / permanent-failure / temporary-failure / technical-failure",  # required string
    "template": {
        "version": 1, # required integer
        "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",  # required string - template ID
        "uri": "/v2/template/{id}/{version}"  # required string
    },
    "body": "STRING",  # required string - body of notification
    "subject": "STRING",  # required string for email - subject of email
    "created_at": "2024-05-17 15:58:38.342838",  # required string - date and time notification created
    "created_by_name": "STRING",  # optional string - name of the person who sent the notification if sent manually
    "sent_at": "2024-05-17 15:58:30.143000",  # optional string - date and time notification sent to provider
    "completed_at": "2024-05-17 15:59:10.321000",  # optional string - date and time notification delivered or failed
    "scheduled_for": "2024-05-17 9:00:00.000000", # optional string - date and time notification has been scheduled to be sent at
    "one_click_unsubscribe": "STRING", # optional string, email only - URL that you provided so your recipients can unsubscribe
    "is_cost_data_ready": True,  # required boolean, this field is true if cost data is ready, and false if it isn't
    "cost_in_pounds": 0.0027,  # optional number - cost of the notification in pounds. The cost does not take free allowance into account
    "cost_details": {
        # for text messages:
        "billable_sms_fragments": 1,  # optional integer - number of billable sms fragments in your text message
        "international_rate_multiplier": 1,  # optional integer - for international sms rate is multiplied by this value
        "sms_rate": 0.0027,  # optional number - cost of 1 sms fragment
        # for letters:
        "billable_sheets_of_paper": 2,  # optional integer - number of sheets of paper in the letter you sent, that you will be charged for
        "postage": "first / second / europe / rest-of-world"  # optional string
    }
}

For more information, see the:

Error codes

If the request is not successful, the client will return an HTTPError containing the relevant error code:

error.status_code error.message How to fix
400 [{
"error": "ValidationError",
"message": "id is not a valid UUID"
}] 		Check the notification ID
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information
404 [{
"error": "NoResultFound",
"message": "No result found"
}] 		Check when your message was sent. If it was sent before the retention period, it has been deleted. You can no longer get the status of this message. The default retention period is 7 days.

Get the status of multiple messages

This API call returns one page of up to 250 messages and statuses. You can get either the most recent messages, or get older messages by specifying a particular notification ID in the older_than argument.

You can only get the status of messages sent within the retention period. The default retention period is 7 days.

Method

All messages

This will return all your messages with statuses. They will display in pages of up to 250 messages each.

response = notifications_client.get_all_notifications(template_type, status, reference, older_than, include_jobs)

You can filter the returned messages by including the following optional arguments in the method:

One page of up to 250 messages

This will return one page of up to 250 messages and statuses. You can get either the most recent messages, or get older messages by specifying a particular notification ID in the older_than argument.

To get the most recent messages, add the following code to your application:

response = get_all_notifications_iterator(status="sending")

You must set the status argument to sending.

To get older messages:

  1. Get the ID of an older message.
  2. Add the following code to your application, with the older notification ID in the older_than argument.
response = get_all_notifications_iterator(status="sending",older_than="NOTIFICATION ID")

You must set the status argument to sending.

This method will return the next oldest messages from the specified notification ID.

Arguments

template_type (optional)

You can filter by:

  • email
  • sms
  • letter

You can leave out this argument to ignore this filter.

status (optional)

You can filter by each:

If you filter by failed it will return all 3 failure statuses: permanent-failure, temporary-failure and technical-failure.

You can leave out this argument to ignore this filter.

reference (optional)

A unique identifier you can create if necessary. This reference identifies a single unique message or a batch of messages. It must not contain any personal information such as name or postal address. For example:

reference='STRING' # optional string - identifies notification(s)

You can leave out this argument to ignore this filter.

older_than (optional)

Input a notification ID into this argument. If you use this argument, the method returns the next 250 received messages older than the given ID.

older_than='740e5834-3a29-46b4-9a6f-16142fde533a' # optional string - notification ID

If you leave out this argument, the method returns the most recent 250 messages.

The client only returns messages sent within the retention period. The default retention period is 7 days. If the message specified in this argument was sent before the retention period, the client returns an empty response.

include_jobs (optional)

Includes notifications sent as part of a batch upload.

If you leave out this argument, the method only returns notifications sent using the API.

Response

If the request to the client is successful, the client returns a dict.

All messages
{
    "notifications": [
        {
            "id": "740e5834-3a29-46b4-9a6f-16142fde533a",  # required string - notification ID
            "reference": "STRING",  # optional string - client reference
            "email_address": "sender@something.com",  # required string for emails
            "phone_number": "+447900900123",  # required string for text messages
            "line_1": "ADDRESS LINE 1",  # required string for letter
            "line_2": "ADDRESS LINE 2",  # required string for letter
            "line_3": "ADDRESS LINE 3",  # required string for letter
            "line_4": "ADDRESS LINE 4",  # optional string for letter
            "line_5": "ADDRESS LINE 5",  # optional string for letter
            "line_6": "ADDRESS LINE 6",  # optional string for letter
            "line_7": "ADDRESS LINE 7", # optional string for letter
            "postage": "first / second / europe / rest-of-world", # required string for letter
            "type": "sms / letter / email",  # required string
            "status": "sending / delivered / permanent-failure / temporary-failure / technical-failure",  # required string
            "template": {
                "version": 1, # required integer
                "id": "f33517ff-2a88-4f6e-b855-c550268ce08a",  # required string - template ID
                "uri": "/v2/template/{id}/{version}"  # required string
            },
            "body": "STRING",  # required string - body of notification
            "subject": "STRING",  # required string for email - subject of email
            "created_at": "2024-05-17 15:58:38.342838",  # required string - date and time notification created
            "created_by_name": "STRING",  # optional string - name of the person who sent the notification if sent manually
            "sent_at": "2024-05-17 15:58:30.143000",  # optional string - date and time notification sent to provider
            "completed_at": "2024-05-17 15:59:10.321000",  # optional string - date and time notification delivered or failed
            "scheduled_for": "2024-05-17 9:00:00.000000", # optional string - date and time notification has been scheduled to be sent at
            "one_click_unsubscribe": "STRING", # optional string, email only - URL that you provided so your recipients can unsubscribe
            "is_cost_data_ready": True,  # required boolean, this field is true if cost data is ready, and false if it isn't
            "cost_in_pounds": 0.0027,  # optional number - cost of the notification in pounds. The cost does not take free allowance into account
            "cost_details": {
                # for text messages:
                "billable_sms_fragments": 1,  # optional integer - number of billable sms fragments in your text message
                "international_rate_multiplier": 1,  # optional integer - for international sms rate is multiplied by this value
                "sms_rate": 0.0027,  # optional number - cost of 1 sms fragment
                # for letters:
                "billable_sheets_of_paper": 2,  # optional integer - number of sheets of paper in the letter you sent, that you will be charged for
                "postage": "first / second / europe / rest-of-world"  # optional string
            }
        }
    ],
    "links": {
        "current": "/notifications?template_type=sms&status=delivered",
        "next": "/notifications?other_than=last_id_in_list&template_type=sms&status=delivered"
    }
}
One page of up to 250 messages
<generator object NotificationsAPIClient.get_all_notifications_iterator at 0x1026c7410>

For more information, see the:

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code:

error.status_code error.message How to fix
400 [{
"error": "ValidationError",
"message": "status ‘elephant’ is not one of [cancelled, created, sending, sent, delivered, pending, failed, technical-failure, temporary-failure, permanent-failure, pending-virus-check, validation-failed, virus-scan-failed, returned-letter, accepted, received]"
}] 		Change the status argument
400 [{
"error": "ValidationError",
"message": "‘Apple’ is not one of [sms, email, letter]"
}] 		Change the template_type argument

Email status descriptions

Status Description
created GOV.UK Notify has placed the message in a queue, ready to be sent to the provider. It should only remain in this state for a few seconds.
sending GOV.UK Notify has sent the message to the provider. The provider will try to deliver the message to the recipient for up to 72 hours. GOV.UK Notify is waiting for delivery information.
delivered The message was successfully delivered.
permanent-failure The provider could not deliver the message because the email address was wrong. You should remove these email addresses from your database.
temporary-failure The provider could not deliver the message. This can happen when the recipient’s inbox is full or their anti-spam filter rejects your email. Check your content does not look like spam before you try to send the message again.
technical-failure Your message was not sent because there was a problem between Notify and the provider.
You’ll have to try sending your messages again.

Text message status descriptions

Status Description
created GOV.UK Notify has placed the message in a queue, ready to be sent to the provider. It should only remain in this state for a few seconds.
sending GOV.UK Notify has sent the message to the provider. The provider will try to deliver the message to the recipient for up to 72 hours. GOV.UK Notify is waiting for delivery information.
pending GOV.UK Notify is waiting for more delivery information.
GOV.UK Notify received a callback from the provider but the recipient’s device has not yet responded. Another callback from the provider determines the final status of the text message.
sent The message was sent to an international number. The mobile networks in some countries do not provide any more delivery information. The GOV.UK Notify website displays this status as ‘Sent to an international number’.
delivered The message was successfully delivered. If a recipient blocks your sender name or mobile number, your message will still show as delivered.
permanent-failure The provider could not deliver the message. This can happen if the phone number was wrong or if the network operator rejects the message. If you’re sure that these phone numbers are correct, you should contact GOV.UK Notify support. If not, you should remove them from your database. You’ll still be charged for text messages that cannot be delivered.
temporary-failure The provider could not deliver the message. This can happen when the recipient’s phone is off, has no signal, or their text message inbox is full. You can try to send the message again. You’ll still be charged for text messages to phones that are not accepting messages.
technical-failure Your message was not sent because there was a problem between Notify and the provider.
You’ll have to try sending your messages again. You will not be charged for text messages that are affected by a technical failure.

Letter status descriptions

Status Description
accepted GOV.UK Notify has sent the letter to the provider to be printed.
received The provider has printed and dispatched the letter.
cancelled Sending cancelled. The letter will not be printed or dispatched.
technical-failure GOV.UK Notify had an unexpected error while sending the letter to our printing provider.
permanent-failure The provider cannot print the letter. Your letter will not be dispatched.

Precompiled letter status descriptions

Status Description
accepted GOV.UK Notify has sent the letter to the provider to be printed.
received The provider has printed and dispatched the letter.
cancelled Sending cancelled. The letter will not be printed or dispatched.
pending-virus-check GOV.UK Notify has not completed a virus scan of the precompiled letter file.
virus-scan-failed GOV.UK Notify found a potential virus in the precompiled letter file.
validation-failed Content in the precompiled letter file is outside the printable area. See the GOV.UK Notify letter specification for more information.
technical-failure GOV.UK Notify had an unexpected error while sending the letter to our printing provider.
permanent-failure The provider cannot print the letter. Your letter will not be dispatched.

Get a PDF for a letter notification

Method

This returns the PDF contents of a letter.

pdf_file = notifications_client.get_pdf_for_letter(
  'f33517ff-2a88-4f6e-b855-c550268ce08a' # required string - notification ID
)

Arguments

notification_id (required)

The ID of the notification. To find the notification ID, you can either:

Response

If the request to the client is successful, the client will return a io.BytesIO object containing the raw PDF data.

Error codes

If the request is not successful, the client will return an HTTPError containing the relevant error code:

error.status_code error.message How to fix
400 [{
"error": "ValidationError",
"message": "id is not a valid UUID"
}] 		Check the notification ID
400 [{
"error": "PDFNotReadyError",
"message": "PDF not available yet, try again later"
}] 		Wait for the letter to finish processing. This usually takes a few seconds
400 [{
"error": "BadRequestError",
"message": "File did not pass the virus scan"
}] 		You cannot retrieve the contents of a letter that contains a virus
400 [{
"error": "BadRequestError",
"message": "PDF not available for letters in technical-failure"
}] 		You cannot retrieve the contents of a letter in technical-failure
400 [{
"error": "ValidationError",
"message": "Notification is not a letter"
}] 		Check that you are looking up the correct notification
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information
404 [{
"error": "NoResultFound",
"message": "No result found"
}] 		Check the notification ID

Get a template

Get a template by ID

Method

This returns the latest version of the template.

response = notifications_client.get_template(
  'f33517ff-2a88-4f6e-b855-c550268ce08a' # required string - template ID
)

Arguments

template_id (required)

The ID of the template. Sign in to GOV.UK Notify and go to the Templates page to find it.

Response

If the request to the client is successful, the client returns a dict.

{
    "id": 'f33517ff-2a88-4f6e-b855-c550268ce08a', # required string - template ID
    "name": "STRING", # required string - template name
    "type": "sms / email / letter" , # required string
    "created_at": "STRING", # required string - date and time template created
    "updated_at": "STRING", # required string - date and time template last updated
    "version": INTEGER,
    "created_by": "someone@example.com", # required string
    "body": "STRING", # required string - body of notification
    "subject": "STRING" # required string for email - subject of email
    "letter_contact_block": "STRING" # optional string - None if not a letter template or contact block not set
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code:

error.status_code error.message How to fix
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information
404 [{
"error": "NoResultFound",
"message": "No Result Found"
}] 		Check your template ID

Get a template by ID and version

Method

response = notifications_client.get_template_version(
    'f33517ff-2a88-4f6e-b855-c550268ce08a' # required string - template ID
    'version': INTEGER,
)

Arguments

template_id (required)

The ID of the template. Sign in to GOV.UK Notify and go to the Templates page to find it.

version (required)

The version number of the template.

Response

If the request to the client is successful, the client returns a dict.

{
    "id": 'f33517ff-2a88-4f6e-b855-c550268ce08a', # required string - template ID
    "name": "STRING", # required string - template name
    "type": "sms / email / letter" , # required string
    "created_at": "STRING", # required string - date and time template created
    "updated_at": "STRING", # required string - date and time template last updated
    "version": INTEGER,
    "created_by": "someone@example.com", # required string
    "body": "STRING", # required string - body of notification
    "subject": "STRING" # required string for email - subject of email
    "letter_contact_block": "STRING" # optional string - None if not a letter template or contact block not set
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code:

error.status_code error.message How to fix
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information
404 [{
"error": "NoResultFound",
"message": "No Result Found"
}] 		Check your template ID and version

Get all templates

Method

This returns the latest version of all templates.

response = notifications_client.get_all_templates(
    template_type="sms / letter / email" # optional string
)

Arguments

template_type (optional)

If you leave out this argument, the method returns all templates. Otherwise you can filter by:

  • email
  • sms
  • letter

Response

If the request to the client is successful, the client returns a dict.

{
    "templates": [
        {
            "id": 'f33517ff-2a88-4f6e-b855-c550268ce08a', # required string - template ID
            "name": "STRING", # required string - template name
            "type": "sms / email / letter" , # required string
            "created_at": "STRING", # required string - date and time template created
            "updated_at": "STRING", # required string - date and time template last updated
            "version": NUMBER, # required string - template version
            "created_by": "someone@example.com", # required string
            "body": "STRING", # required string - body of notification
            "subject": "STRING" # required string for email - subject of email
            "letter_contact_block": "STRING" # optional string - None if not a letter template or contact block not set
        },
        {
            ...another template
        }
    ]
}

If no templates exist for a template type or there no templates for a service, the client returns a dict with an empty templates list element:

{
    "templates": []
}

Generate a preview template

Method

This generates a preview version of a template.

response = notifications_client.post_template_preview(
    template_id='f33517ff-2a88-4f6e-b855-c550268ce08a', # required UUID string
    personalisation={
        'KEY': 'VALUE',
        'KEY': 'VALUE',
        ...
        }, # required dict - specifies template parameters
)

The parameters in the personalisation argument must match the placeholder fields in the actual template. The API notification client will ignore any extra fields in the method.

Arguments

template_id (required)

The ID of the template. Sign in to GOV.UK Notify and go to the Templates page to find it.

personalisation (required)

If a template has placeholder fields for personalised information such as name or reference number, you need to provide their values in a dictionary with key value pairs. For example:

personalisation={
    'first_name': 'Amala',
    'application_date': '2018-01-01',
}

Response

If the request to the client is successful, you receive a dict response.

{
    "id": "740e5834-3a29-46b4-9a6f-16142fde533a", # required string - notification ID
    "type": "sms / email / letter" , # required string
    "version": INTEGER,
    "body": "STRING", # required string - body of notification
    "subject": "STRING" # required string for email - subject of email
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code:

error.status_code error.message Notes
400 [{
"error": "BadRequestError",
"message": "Missing personalisation: [PERSONALISATION FIELD]"
}] 		Check that the personalisation arguments in the method match the placeholder fields in the template
400 [{
"error": "NoResultFound",
"message": "No result found"
}] 		Check the template ID
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information

Get received text messages

This API call returns one page of up to 250 received text messages. You can get either the most recent messages, or get older messages by specifying a particular notification ID in the older_than argument.

You can only get the status of messages that are 7 days old or newer.

Enable received text messages

To receive text messages:

  1. Go to the Text message settings section of the Settings page.
  2. Select Change on the Receive text messages row.

Get all received text messages

This method returns a <generator object> with all received text messages.

Method

response = get_received_texts_iterator()

Response

If the request to the client is successful, the client will return a <generator object> that will return all received text messages.

<generator object NotificationsAPIClient.get_received_texts_iterator at 0x1026c7410>

Get a page of received text messages

This will return one page of up to 250 text messages.

Method

response = client.get_received_texts(older_than)

You can specify which text messages to receive by inputting the ID of a received text message into the older_than argument.

Arguments

older_than (optional)

Input the ID of a received text message into this argument. If you use this argument, the method returns the next 250 received text messages older than the given ID.

older_than='740e5834-3a29-46b4-9a6f-16142fde533a' # optional string - notification ID

If you leave out this argument, the method returns the most recent 250 text messages.

Response

If the request to the client is successful, the client returns a dict.

{
  "received_text_messages":
  [
    {
      "id": "STRING", # required string - ID of received text message
      "user_number": "STRING", # required string
      "notify_number": "STRING", # required string - receiving number
      "created_at": "STRING", # required string - date and time template created
      "service_id": "STRING", # required string - service ID
      "content": "STRING" # required string - text content
    },
    …
  ],
  "links": {
    "current": "/received-text-messages",
    "next": "/received-text-messages?other_than=last_id_in_list"
  }
}

Error codes

If the request is not successful, the client returns an HTTPError containing the relevant error code.

error.status_code error.message How to fix
403 [{
"error": "AuthError",
"message": "Error: Your system clock must be accurate to within 30 seconds"
}] 		Check your system clock
403 [{
"error": "AuthError",
"message": "Invalid token: API key not found"
}] 		Use the correct API key. Refer to API keys for more information

Error messages

Error messages consist of:

  • a status_code, for example ‘400’
  • an error, for example ’BadRequestError’
  • a message, for example ‘Mobile numbers can only include: 0 1 2 3 4 5 6 7 8 9 ( ) + -‘

Do not use the content of the messages in your code. These can sometimes change, which may affect your API integration.

Use the status_code or the error instead, as these will not change.

Find error codes in:

Testing

All testing takes place in the production environment. There is no test environment for GOV.UK Notify.

Smoke testing

If you need to smoke test your integration with Notify on a regular basis, you must use the following smoke test phone numbers and email addresses.

Phone numbers

  • 07700900000
  • 07700900111
  • 07700900222

Email addresses

  • simulate-delivered@notifications.service.gov.uk
  • simulate-delivered-2@notifications.service.gov.uk
  • simulate-delivered-3@notifications.service.gov.uk

The smoke test phone numbers and email addresses will validate the request and simulate a successful response, but will not send a real message, produce a delivery receipt or persist the notification to the database.

You can use these smoke test numbers and addresses with any type of API key.

You can smoke test all Notify API client functions except:

  • Get the status of one message
  • Get the status of all messages

You cannot use the smoke test phone numbers or email address with these functions because they return a fake notification_ID. If you need to test these functions, use a test API key and any other phone number or email.

Other testing

You must use a test API key to do non-smoke testing such as performance or integration testing. You can use any non-smoke testing phone numbers or email addresses. You do not need a specific Notify testing account.

API keys

There are three different types of API keys:

  • test
  • team and guest list
  • live

When you set up a new service it will start in trial mode. A service in trial mode can create test and team and guest list keys. You must have a live service to create a live key.

To create an API key:

  1. Sign in to GOV.UK Notify.
  2. Go to the API integration page.
  3. Select API keys.
  4. Select Create an API key.

Test

Use a test key to test the performance of your service and its integration with GOV.UK Notify.

Messages sent using a test key:

  • generate realistic responses
  • result in a delivered status
  • are not actually delivered to a recipient
  • do not appear on your dashboard
  • do not count against your text message and email allowances

To test failure responses with a test key, use the following numbers and addresses:

Phone number/Email address Response
07700900003 temporary-failure
07700900002 permanent-failure
temp-fail@simulator.notify temporary-failure
perm-fail@simulator.notify permanent-failure
any other valid number or address delivered

You do not have to revoke test keys.

Team and guest list

A team and guest list key lets you send real messages to your team members and addresses/numbers on your guest list while your service is still in trial mode.

You will get an error if you use these keys to send messages to anyone who is not on your team or your guest list.

Messages sent with a team and guest list key appear on your dashboard and count against your text message and email allowances.

You do not have to revoke team and guest list keys.

Live

You can only create live keys once your service is live. You can use live keys to send messages to anyone.

Messages sent with a live key appear on your dashboard and count against your text message and email allowances.

You should revoke and re-create these keys on a regular basis. To revoke a key:

  1. Sign in to GOV.UK Notify.
  2. Go to the API integration page.
  3. Select API keys.
  4. Select Revoke for the API key you want to revoke.

You can have more than one active key at a time.

You should never send test messages to invalid numbers or addresses using a live key.

Limits

Rate limits

You’re limited to sending 3,000 messages per minute.

This limit is calculated on a rolling basis, per API key type. If you exceed the limit, you will get a 429 error RateLimitError.

Daily limits

There’s a limit to the number of messages you can send each day:

Service status Type of API key Daily limit
Live Team or live
  • 250,000 emails
  • 250,000 text messages
  • 20,000 letters
Trial Team 50 emails or text messages
Live or trial Test Unlimited

These limits reset at midnight UTC.

Phone network limits

If you repeatedly send text messages to the same number the phone networks will block them.

There’s an hourly limit of:

  • 20 messages with the same content
  • 100 messages with any content

Your messages may not be delivered if you exceed these limits.

Callbacks

Callbacks are when GOV.UK Notify sends POST requests to your service. You can get callbacks when:

  • a text message or email you’ve sent is delivered or fails
  • your service receives a text message

Set up callbacks

You must provide:

  • a URL where Notify will post the callback to
  • a bearer token which Notify will put in the authorisation header of the requests

To do this:

  1. Sign in to GOV.UK Notify.
  2. Go to the API integration page.
  3. Select Callbacks.

Retry callbacks

If Notify sends a POST request to your service, but the request fails then we will retry.

We will retry every 5 minutes, up to a maximum of 5 times.

Delivery receipts

When you send an email or text message, Notify will send a receipt to your callback URL with the status of the message. This is an automated method to get the status of messages.

This functionality works with test API keys, but does not work with smoke testing phone numbers or email addresses.

The callback message is formatted in JSON. All of the values are strings, apart from the template version, which is a number. The key, description and format of the callback message arguments will be:

Key Description Format
id Notify’s id for the status receipts UUID
reference The reference sent by the service 12345678 or null
to The email address or phone number of the recipient hello@gov.uk or 07700912345
status The status of the notification delivered, permanent-failure, temporary-failure or technical-failure
created_at The time the service sent the request 2017-05-14T12:15:30.000000Z
completed_at The last time the status was updated 2017-05-14T12:15:30.000000Z or null
sent_at The time the notification was sent 2017-05-14T12:15:30.000000Z or null
notification_type The notification type email or sms
template_id The id of the template that was used UUID
template_version The version number of the template that was used 1

Received text messages

If your service receives text messages in Notify, Notify can forward them to your callback URL as soon as they arrive.

Find out how to let people send text messages to your service.

The callback message is formatted in JSON. All of the values are strings. The key, description and format of the callback message arguments will be:

Key Description Format
id Notify’s id for the received message UUID
source_number The phone number the message was sent from 447700912345
destination_number The number the message was sent to (your number) 07700987654
message The received message Hello Notify!
date_received The UTC datetime that the message was received by Notify 2017-05-14T12:15:30.000000Z

API architecture

Architecture for sending a text message

  1. The service sends a text message notification to Notify.
  2. Notify sends the text message to the provider.
  3. The provider delivers the text message to the recipient.
  4. The recipient receives the text message and sends a delivery receipt to the provider.
  5. The provider sends the delivery receipt to Notify.
  6. Notify receives the delivery receipt and sends an API response to the service.
  7. The service receives the API response.

Architecture for sending an email

  1. The service sends an email notification to Notify.
  2. Notify sends the email to the provider.
  3. The provider delivers the email to the recipient.
  4. The recipient receives the email and sends a delivery receipt to the provider.
  5. The provider sends the delivery receipt to Notify.
  6. Notify receives the delivery receipt and sends an API response to the service.
  7. The service receives the API response.

Architecture for sending a letter

  1. The service sends a letter notification to Notify.
  2. Notify sends the letter to the provider.
  3. The provider prints the letter and posts it.
  4. The postal service delivers the letter.
  5. The recipient receives the letter.

Architecture for getting the status of a message

  1. The service requests a notification status from Notify.
  2. Notify queries the database and retrieves the notification status.
  3. Notify sends the API response with the notification status to the service.
  4. The service receives the API response.

Architecture for getting received text messages

  1. Recipients send text messages.
  2. Notify receives the text messages.
  3. The service requests all or specific received text messages from Notify.
  4. Notify receives the request for received text messages.
  5. Notify sends the received text messages to the service.
  6. The service receives the received text messages.