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API Monitoring

An API (Application Programming Interface) is software that enables the communication between applications. Maybe you are using your own APIs and/or you rely on third-party APIs. Either way, the correct functioning of the APIs is crucial to the operation of your website and services, therefore you should monitor them.

API monitoring checks whether the APIs that you rely on are available, function correctly and perform well. More information can be found in the article What is API monitoring?.

Uptrends API monitoring offers different types of monitors to set up API monitoring. The choice of type depends on whether you have to deal with a single step or with a chain of requests consisting of multiple steps. The single-step monitor is defined using the Webservice HTTP or Webservice HTTPS monitor type. The monitor for a sequence of steps is defined using the Multi-step API monitor (MSA monitor) type.

The Uptrends app has a Multi-step API monitor hub where knowledge about these monitors and the current status can be found in one place.

Setting up API monitors

The setup of the different types of monitors is documented in these articles:

Defining Multi-step API monitor steps

When setting up a Multi-step API monitor you have to define the steps containing the HTTP requests that are part of the scenario you want to monitor. For each step you have to set the details for the request and the response part of the step. There are also some definitions for user-defined functions, variables and metrics. These are set globally (available to all steps). Check out the articles in the sections below to learn more about setting up the HTTP steps.


The HTTP step request is set up by providing a method and a URL and the request body, then specifying further details like the authentication. See the articles below for more information.


Within the response of the step you should define assertions. Assertions are checks that go one step beyond the question if there is a response to the request. An assertion will also check if the response is valid or arrives in time. For each step you can define a number of assertions. Find more information about assertions in these articles:

Global definitions

There are a number of things that you can define for all steps and both the request and response part of them. This comes in handy if you want to use a certain value or function across different steps. Read on in the following articles to find out more:

Script view

You can also edit Multi-step API monitor step definitions directly in the script view. See our article on the MSA script editor for more information.

All articles in this category

  • Hashing and/or encoding values
    For certain use-cases of API monitoring, it may be necessary to hash or encode variables or values. For example, authorization setups might require Base64 encoding or HMAC-SHA256 hashing in order to work correctly, or you might need to include encoded JSON in your request body. To this end, Uptrends offers several encoding and hashing options, which will be described in this article. Encoding and decoding Encoding is a process to ensure data can be sent in a reliable way, in a particular form.
  • Monitoring Web Services
    You may be familiar with Uptrends’ website monitoring and server monitor types, but Uptrends also supports monitoring the uptime of web services. Read on below to learn more… Which Web Services are supported? Uptrends supports REST, and SOAP, as well as any web services reachable through HTTP, HTTPS. How do these Web Services work with Uptrends? We monitor that the web service response is HTTP 200 OK, and measure resolve time/connection time, download time, and total time, just like HTTP(S) monitors Web service monitoring also supports Basic Authentication, content checks, etc.
  • Multi-step API monitor hub
    Your starting place when exploring Multi-step API monitoring
  • Multi-step API script editor
    An overview of the Multi-step API monitor script editor
  • Multi-step monitoring
    Learn how to work with redirects within your Multi-step API Monitors.
  • Multi-step monitoring Assertions
    Understanding assertions in Multi-step API Monitoring.
  • Multi-step monitoring Authentication
    Learn about the available options for authentication when using Multi-step API Monitoring.
  • Multi-step monitoring Client certificate authentication
    Many APIs require that the caller specifies authentication information to verify their identity, and possibly the access rights of that caller. Authentication information can be passed along using HTTP headers (Basic/NTLM/Digest authentication), by exchanging access tokens (OAuth), by requiring the client to include a client certificate in the request, or a combination. This article discusses the options for client certificates. To set up traditional authentication methods, please read the article on authentication types.
  • Multi-step monitoring comparison operators
    Learn about the comparison operators available to you when setting up Multi-Step API Monitoring.
  • Multi-step monitoring sources
    How to extract values for assertions or variable assignment when setting up Multi-step API Monitoring.
  • Multi-step monitoring Variables
    How to use variables for storage of values extracted from your API responses for use in later steps.
  • Multi-step monitoring XPath examples
    This article features several examples for extracting content from XML responses using XPath. These XPath queries allow you inspect an XML response coming back from your API or web service as part of a Multi-step API monitor. An XPath query defines which part of the XML response you are interested in - typically a value contained in one of the XML nodes. You can then take that extracted value and check whether it satisfies certain conditions (using assertions), or store it in a variable for later use.
  • Setting up Custom API metric monitoring
    This article describes how you can use the Custom Metrics feature to capture data from APIs. This could be the API of a technical partner you are using for your business, or your own API that you’ve built to support your own customers or processes. It could even be a custom API you’ve built to collect or calculate your internal business metrics or platform metrics. Test tools and monitoring solutions help you to ensure your APIs work correctly, and this should be a vital part of your platform operations.
  • Setting up Multi-step API Monitoring
    Step-by-step instructions for setting up Multi-step API Monitoring.
  • SOAP Setup
    If you’re looking to add a SOAP monitor to your Uptrends account, you’ll find the instructions in this article. Setting up a SOAP Web Service monitor To test a SOAP service, you typically want to call a method of that web service, by posting input data to it in the form of a SOAP envelope and then verifying that the response is correct. Get to the Add Monitor configuration screen.
  • Uptrends' client certificate public key information
    By using the Uptrends public key with your Multi-step API monitor, you ensure that API monitor requests originate from Uptrends.
  • User-defined functions
    An overview of available user-defined functions and how to use them
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