API reference

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The Elastic APM Python agent has several public APIs. Most of the public API functionality is not needed when using one of our supported frameworks, but they allow customized usage.

Client API

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The public Client API consists of several methods on the Client class. This API can be used to track exceptions and log messages, as well as to mark the beginning and end of transactions.

Instantiation

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Added in v1.0.0.

To create a Client instance, import it and call its constructor:

from elasticapm import Client

client = Client({'SERVICE_NAME': 'example'}, **defaults)
  • config: A dictionary, with key/value configuration. For the possible configuration keys, see Configuration.
  • **defaults: default values for configuration. These can be omitted in most cases, and take the least precedence.

framework integrations like Django and Flask instantiate the client automatically.

elasticapm.get_client()
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[small]#Added in v6.1.0.

Retrieves the Client singleton. This is useful for many framework integrations, where the client is instantiated automatically.

client = elasticapm.get_client()
client.capture_message('foo')

Errors

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Client.capture_exception()
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Added in v1.0.0. handled added in v2.0.0.

Captures an exception object:

try:
    x = int("five")
except ValueError:
    client.capture_exception()
  • exc_info: A (type, value, traceback) tuple as returned by sys.exc_info(). If not provided, it will be captured automatically.
  • date: A datetime.datetime object representing the occurrence time of the error. If left empty, it defaults to datetime.datetime.utcnow().
  • context: A dictionary with contextual information. This dictionary must follow the Context schema definition.
  • custom: A dictionary of custom data you want to attach to the event.
  • handled: A boolean to indicate if this exception was handled or not.

Returns the id of the error as a string.

Client.capture_message()
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Added in v1.0.0.

Captures a message with optional added contextual data. Example:

client.capture_message('Billing process succeeded.')
  • message: The message as a string.
  • param_message: Alternatively, a parameterized message as a dictionary. The dictionary contains two values: message, and params. This allows the APM Server to group messages together that share the same parameterized message. Example:

    client.capture_message(param_message={
        'message': 'Billing process for %s succeeded. Amount: %s',
        'params': (customer.id, order.total_amount),
    })
  • stack: If set to True (the default), a stacktrace from the call site will be captured.
  • exc_info: A (type, value, traceback) tuple as returned by sys.exc_info(). If not provided, it will be captured automatically, if capture_message() was called in an except block.
  • date: A datetime.datetime object representing the occurrence time of the error. If left empty, it defaults to datetime.datetime.utcnow().
  • context: A dictionary with contextual information. This dictionary must follow the Context schema definition.
  • custom: A dictionary of custom data you want to attach to the event.

Returns the id of the message as a string.

Either the message or the param_message argument is required.

Transactions

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Client.begin_transaction()
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Added in v1.0.0. trace_parent support added in v5.6.0.

Begin tracking a transaction. Should be called e.g. at the beginning of a request or when starting a background task. Example:

client.begin_transaction('processors')
  • transaction_type: (required) A string describing the type of the transaction, e.g. 'request' or 'celery'.
  • trace_parent: (optional) A TraceParent object. See TraceParent generation.
  • links: (optional) A list of TraceParent objects to which this transaction is causally linked.
Client.end_transaction()
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Added in v1.0.0.

End tracking the transaction. Should be called e.g. at the end of a request or when ending a background task. Example:

client.end_transaction('myapp.billing_process', processor.status)
  • name: (optional) A string describing the name of the transaction, e.g. process_order. This is typically the name of the view/controller that handles the request, or the route name.
  • result: (optional) A string describing the result of the transaction. This is typically the HTTP status code, or e.g. 'success' for a background task.

if name and result are not set in the end_transaction() call, they have to be set beforehand by calling elasticapm.set_transaction_name() and elasticapm.set_transaction_result() during the transaction.

TraceParent

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Transactions can be started with a TraceParent object. This creates a transaction that is a child of the TraceParent, which is essential for distributed tracing.

elasticapm.trace_parent_from_string()
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Added in v5.6.0.

Create a TraceParent object from the string representation generated by TraceParent.to_string():

parent = elasticapm.trace_parent_from_string('00-03d67dcdd62b7c0f7a675424347eee3a-5f0e87be26015733-01')
client.begin_transaction('processors', trace_parent=parent)
  • traceparent_string: (required) A string representation of a TraceParent object.
elasticapm.trace_parent_from_headers()
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Added in v5.6.0.

Create a TraceParent object from HTTP headers (usually generated by another Elastic APM agent):

parent = elasticapm.trace_parent_from_headers(headers_dict)
client.begin_transaction('processors', trace_parent=parent)
  • headers: (required) HTTP headers formed as a dictionary.
elasticapm.get_trace_parent_header()
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Added in v5.10.0.

Return the string representation of the current transaction TraceParent object:

elasticapm.get_trace_parent_header()

Other APIs

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elasticapm.instrument()

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Added in v1.0.0.

Instruments libraries automatically. This includes a wide range of standard library and 3rd party modules. A list of instrumented modules can be found in elasticapm.instrumentation.register. This function should be called as early as possibly in the startup of your application. For supported frameworks, this is called automatically. Example:

import elasticapm

elasticapm.instrument()

elasticapm.set_transaction_name()

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Added in v1.0.0.

Set the name of the current transaction. For supported frameworks, the transaction name is determined automatically, and can be overridden using this function. Example:

import elasticapm

elasticapm.set_transaction_name('myapp.billing_process')
  • name: (required) A string describing name of the transaction
  • override: if True (the default), overrides any previously set transaction name. If False, only sets the name if the transaction name hasn’t already been set.

elasticapm.set_transaction_result()

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Added in v2.2.0.

Set the result of the current transaction. For supported frameworks, the transaction result is determined automatically, and can be overridden using this function. Example:

import elasticapm

elasticapm.set_transaction_result('SUCCESS')
  • result: (required) A string describing the result of the transaction, e.g. HTTP 2xx or SUCCESS
  • override: if True (the default), overrides any previously set result. If False, only sets the result if the result hasn’t already been set.

elasticapm.set_transaction_outcome()

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Added in v5.9.0.

Sets the outcome of the transaction. The value can either be "success", "failure" or "unknown". This should only be called at the end of a transaction after the outcome is determined.

The outcome is used for error rate calculations. success denotes that a transaction has concluded successful, while failure indicates that the transaction failed to finish successfully. If the outcome is set to unknown, the transaction will not be included in error rate calculations.

For supported web frameworks, the transaction outcome is set automatically if it has not been set yet, based on the HTTP status code. A status code below 500 is considered a success, while any value of 500 or higher is counted as a failure.

If your transaction results in an HTTP response, you can alternatively provide the HTTP status code.

While the outcome and result field look very similar, they serve different purposes. Other than the result field, which canhold an arbitrary string value, outcome is limited to three different values, "success", "failure" and "unknown". This allows the APM app to perform error rate calculations on these values.

Example:

import elasticapm

elasticapm.set_transaction_outcome("success")

# Using an HTTP status code
elasticapm.set_transaction_outcome(http_status_code=200)

# Using predefined constants:

from elasticapm.conf.constants import OUTCOME

elasticapm.set_transaction_outcome(OUTCOME.SUCCESS)
elasticapm.set_transaction_outcome(OUTCOME.FAILURE)
elasticapm.set_transaction_outcome(OUTCOME.UNKNOWN)
  • outcome: One of "success", "failure" or "unknown". Can be omitted if http_status_code is provided.
  • http_status_code: if the transaction represents an HTTP response, its status code can be provided to determine the outcome automatically.
  • override: if True (the default), any previously set outcome will be overriden. If False, the outcome will only be set if it was not set before.

elasticapm.get_transaction_id()

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Added in v5.2.0.

Get the id of the current transaction. Example:

import elasticapm

transaction_id = elasticapm.get_transaction_id()

elasticapm.get_trace_id()

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Added in v5.2.0.

Get the trace_id of the current transaction’s trace. Example:

import elasticapm

trace_id = elasticapm.get_trace_id()

elasticapm.get_span_id()

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Added in v5.2.0.

Get the id of the current span. Example:

import elasticapm

span_id = elasticapm.get_span_id()

elasticapm.set_custom_context()

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Added in v2.0.0.

Attach custom contextual data to the current transaction and errors. Supported frameworks will automatically attach information about the HTTP request and the logged in user. You can attach further data using this function.

Before using custom context, ensure you understand the different types of metadata that are available.

Example:

import elasticapm

elasticapm.set_custom_context({'billing_amount': product.price * item_count})
  • data: (required) A dictionary with the data to be attached. This should be a flat key/value dict object.

., *, and " are invalid characters for key names and will be replaced with _.

Errors that happen after this call will also have the custom context attached to them. You can call this function multiple times, new context data will be merged with existing data, following the update() semantics of Python dictionaries.

elasticapm.set_user_context()

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Added in v2.0.0.

Attach information about the currently logged in user to the current transaction and errors. Example:

import elasticapm

elasticapm.set_user_context(username=user.username, email=user.email, user_id=user.id)
  • username: The username of the logged in user
  • email: The email of the logged in user
  • user_id: The unique identifier of the logged in user, e.g. the primary key value

Errors that happen after this call will also have the user context attached to them. You can call this function multiple times, new user data will be merged with existing data, following the update() semantics of Python dictionaries.

elasticapm.capture_span

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Added in v4.1.0.

Capture a custom span. This can be used either as a function decorator or as a context manager (in a with statement). When used as a decorator, the name of the span will be set to the name of the function. When used as a context manager, a name has to be provided.

import elasticapm

@elasticapm.capture_span()
def coffee_maker(strength):
    fetch_water()

    with elasticapm.capture_span('near-to-machine', labels={"type": "arabica"}):
        insert_filter()
        for i in range(strength):
            pour_coffee()

        start_drip()

    fresh_pots()
  • name: The name of the span. Defaults to the function name if used as a decorator.
  • span_type: (optional) The type of the span, usually in a dot-separated hierarchy of type, subtype, and action, e.g. db.mysql.query. Alternatively, type, subtype and action can be provided as three separate arguments, see span_subtype and span_action.
  • skip_frames: (optional) The number of stack frames to skip when collecting stack traces. Defaults to 0.
  • leaf: (optional) if True, all spans nested bellow this span will be ignored. Defaults to False.
  • labels: (optional) a dictionary of labels. Keys must be strings, values can be strings, booleans, or numerical (int, float, decimal.Decimal). Defaults to None.
  • span_subtype: (optional) subtype of the span, e.g. name of the database. Defaults to None.
  • span_action: (optional) action of the span, e.g. query. Defaults to None.
  • links: (optional) A list of TraceParent objects to which this span is causally linked.

elasticapm.async_capture_span

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Added in v5.4.0.

Capture a custom async-aware span. This can be used either as a function decorator or as a context manager (in an async with statement). When used as a decorator, the name of the span will be set to the name of the function. When used as a context manager, a name has to be provided.

import elasticapm

@elasticapm.async_capture_span()
async def coffee_maker(strength):
    await fetch_water()

    async with elasticapm.async_capture_span('near-to-machine', labels={"type": "arabica"}):
        await insert_filter()
        async for i in range(strength):
            await pour_coffee()

        start_drip()

    fresh_pots()
  • name: The name of the span. Defaults to the function name if used as a decorator.
  • span_type: (optional) The type of the span, usually in a dot-separated hierarchy of type, subtype, and action, e.g. db.mysql.query. Alternatively, type, subtype and action can be provided as three separate arguments, see span_subtype and span_action.
  • skip_frames: (optional) The number of stack frames to skip when collecting stack traces. Defaults to 0.
  • leaf: (optional) if True, all spans nested bellow this span will be ignored. Defaults to False.
  • labels: (optional) a dictionary of labels. Keys must be strings, values can be strings, booleans, or numerical (int, float, decimal.Decimal). Defaults to None.
  • span_subtype: (optional) subtype of the span, e.g. name of the database. Defaults to None.
  • span_action: (optional) action of the span, e.g. query. Defaults to None.
  • links: (optional) A list of TraceParent objects to which this span is causally linked.

asyncio is only supported for Python 3.7+.

elasticapm.label()

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Added in v5.0.0.

Attach labels to the the current transaction and errors.

Before using custom labels, ensure you understand the different types of metadata that are available.

Example:

import elasticapm

elasticapm.label(ecommerce=True, dollar_value=47.12)

Errors that happen after this call will also have the labels attached to them. You can call this function multiple times, new labels will be merged with existing labels, following the update() semantics of Python dictionaries.

Keys must be strings, values can be strings, booleans, or numerical (int, float, decimal.Decimal) ., *, and " are invalid characters for label names and will be replaced with _.

Avoid defining too many user-specified labels. Defining too many unique fields in an index is a condition that can lead to a mapping explosion.