MultiHTTP check

MultiHTTP checks can test multiple URLs in a single check while measuring uptime and response latency like other check types. You can also use the results of one request in a later one and make several assertions for each request.

Options

The list of common options to all check types:

Option	Description
Enabled	Whether the check is enabled or not.
Job name	Refer to the check name. Check metrics include a `job` label with the value of this option.
Target	Target of the check request. Check metrics include an `instance` label with the value of this option.
Probe locations	The locations where the check should run from. Check metrics include a `probe` label with the value of the probe location running the check.
Frequency	The frequency the check should run in seconds. The value can range from 60 to 3600 seconds. Only the `sm_check_info` metric includes the `frequency` label.
Timeout	Maximum execution time for the check. The value can range from 1 to 60 seconds.
Custom labels	(Optional) Custom labels applied to check metrics. Refer to Custom labels for querying instructions.

Additionally, MultiHTTP checks have the following options:

Option	Description
Request target	The URL to send a request to.
Request method	The HTTP method to use when sending the request.
Headers	Name and value of HTTP headers to add to the request.
Query parameters	Name and value of URL query parameters.
Assertions	See below.
Variables	See below.

These last options don’t produce any additional labels in the resulting check metrics.

Assertions

There are four types of assertions.

Text assertions

Text assertions match a simple string against various subjects:

Body: The entire response body is used.
Headers: Each individual header is matched against the specified value. The header name is lower-cased, followed by a colon and a space (: ), followed by the header’s value (as is). The match succeeds if at least one of the headers matches.
Status code: The status code is used.

The match can be performed against the specified subject in one of several ways:

Contains: The specified value must be present somewhere in the subject.
Does not contain: The specified value must not be present anywhere in the subject.
Equals: The subject must be exactly equal to the specified value.
Starts with: The subject must start with the specified value.
Ends with: The subject must end with the specified value.

JSON path value assertions

This type of assertion expects the response body to be a JSON document, and it accepts a JSONPath expression to be matched against the specified value. The possible matches are:

Contains: The specified value must be present somewhere in the result of evaluating the JSONPath expression.
Does not contain: The specified value must not be present anywhere in the result of evaluating the JSONPath expression.
Equals: The result of evaluating the JSONPath expression must be exactly equal to the specified value.
Starts with: The result of evaluating the JSONPath expression must start with the specified value.
Ends with: The result of evaluating the JSONPath expression must end with the specified value.

JSON path assertions

This type of assertion expects the response body to be a JSON document, and it accepts a JSONPath expression that must evaluate to a non-empty result for the assertion to succeed.

Regex assertions

Regular expression assertions evaluate the provided regular expresion against one of various subjects:

Body: The entire response body is used.
Headers: Each individual header is evaluated against the specified regular expression. The header name is lower-cased, followed by a colon and a space (: ), followed by the header’s value (as is). The match succeeds if at least one of the headers matches.
Status code: The status code is used.

Variables

Variables can capture values from the responses to individual HTTP requests. Each variable must be named, and the name must be unique across all requests. The name can be used in subsequent requests by using the ${name} variable. It’s possible to use this anywhere where a string is expected, for example, as the value of a header or the value of an assertion.

Variable values can be obtained from the following.

A JSONPath: The value of the variable is the result of evaluating the JSONPath expression.
A regular expression: The value of the variable is the string matching the regular expression.
A CSS selector: The value of the variable is the value of evaluating the CSS selector against the response body. Optionally, an attribute name can be specified, in which case the value of the variable is the value of the specified attribute.

Metrics

Checks store their results as Prometheus metrics, including the list of common metrics:

Metric	Description
`probe_all_duration_seconds`	Returns how long the probe took to complete in seconds (histogram).
`probe_duration_seconds`	Returns how long the probe took to complete in seconds.
`probe_all_success`	Displays whether or not the probe was a success (summary).
`probe_success`	Displays whether or not the probe was a success.
`sm_check_info`	Provides information about a single check configuration.

Additionally, MultiHTTP checks produce the following metrics:

Metric	Description
`probe_data_received_bytes`	The total number of bytes received.
`probe_data_sent_bytes`	The total number of bytes sent.
`probe_http_duration_seconds`	For each method and URL group, its duration in seconds, split by phase (resolve, connect, TLS, processing, transfer).
`probe_http_info`	Information about the response.
`probe_http_requests_failed_total`	The number of failed requests by method and URL.
`probe_http_requests_total`	The total number of requests by method and URL.
`probe_http_ssl`	For each method and URL group, whether or not the request used SSL.
`probe_http_status_code`	For each method and URL group, the response code for the request.
`probe_http_version`	For each method and URL group, the version of the HTTP protocol used to complete the request.
`probe_iteration_duration_seconds`	The total number of seconds for the whole check, excluding setup time for the check itself.