What exactly is an API?

API stands for Application Programming Interface and allows different applications to connect with each other to share data and functionality. APIs are typically integrated through an integration platform, an application, or custom development.

An API typically consists of a set of endpoints that are accessible over the Internet. Applications can send requests to these endpoints to retrieve specific data or perform functions. The API processes the request and returns a response that is either sent directly to the application or indirectly back through additional API endpoints.

API standards

API standards are collections of rules, protocols, and best practices that define how APIs are developed, structured, and used. They enable clear communication between different applications and systems. Well-known API standards include REST, SOAP, GraphQL, and webhooks. By adhering to these standards, interactions between software components run smoothly and predictably. API standards promote interoperability and scalability, which facilitates the development of innovative solutions.


The Representational State Transfer (REST) architecture is an API design characterized by simple, lightweight, and scalable solutions. REST APIs typically use HTTP methods such as GET, POST, PUT, and DELETE to communicate with resources.


The Simple Object Access Protocol (SOAP) is an XML-based protocol designed for exchanging data over the Internet. It was originally designed for distributed applications and supports communication between different platforms and programming languages.


GraphQL is a flexible query language and runtime for manipulating and querying data via APIs. It allows clients to query exactly the data they need, reducing network traffic.


OData (Open Data Protocol) is a powerful and flexible protocol for exchanging data over the Internet, designed specifically for implementation in APIs. As a web-based protocol, OData is based on established technologies such as HTTP, JSON and AtomPub to enable communication and interaction between different applications and systems.


Webhooks are a powerful technology that allows an application to respond to specific events or activities in another application. They do this by calling a predefined URL called a “webhook endpoint.” Once a specific event occurs, the application where the event takes place sends a notification to the registered webhook URL. This notification usually contains information about the triggering event and allows the receiving application to perform or respond to appropriate actions. Webhooks thus provide an efficient and flexible way to enable real-time communication and interaction between different systems and applications without relying on regular polling or querying.

How can API standards be combined seamlessly during integration?

The Marini Integration Platform provides a solution for efficiently combining different API standards during integration. With its no-coding user interface, the platform enables user-friendly handling and interaction with the various API standards. Regardless of the standards used, such as REST, SOAP, GraphQL or Webhooks, all systems that provide APIs can be integrated easily, robustly and quickly. Using Marini simplifies and accelerates the integration process, while ensuring high reliability and consistency in communication between the systems involved.

Discover REST APIs: a comprehensive video tutorial

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API endpoints

Mode of operation: An API consists of multiple API endpoints that are accessible over the Internet.

Requests and responses: Applications send requests to these endpoints to retrieve or execute data or functions. The API processes the request and provides a response that is returned to the application directly or indirectly through other API endpoints.

API Methods

API methods are actions that can be applied to resources through the API. They enable interaction with resources and affect their state. In REST APIs, standard HTTP methods are often used to perform basic CRUD (Create, Read, Update, Delete) operations.

GET: The GET method is used to retrieve data from a resource without changing its state. It is idempotent, meaning that repeated requests have the same effect as a single request.

POST: The POST method creates a new resource or adds data to an existing resource. It is not idempotent, as repeated requests may produce different results.

PUT: The PUT method updates an existing resource or creates it if it does not already exist. Unlike the POST method, PUT is idempotent, since repeated requests have the same effect as a single request.

PATCH: The PATCH method partially modifies an existing resource by updating only the specified attributes. Unlike PUT, PATCH does not overwrite the entire resource, but makes selective changes. The idempotency of PATCH requests depends on the specific implementation.

DELETE: The DELETE method deletes a resource and is idempotent. After a resource is deleted, repeated DELETE requests have the same effect as a single request, i.e. the resource is no longer present.

In addition to basic HTTP methods, APIs can also provide custom methods or actions that perform specific functions or processes within an application. These methods can be called through specific API endpoints and extend the functionality of the API beyond the standard HTTP methods.

Application examples

Data Exchange: APIs facilitate data exchange between applications and enable the aggregation of information from multiple sources for analysis and reporting purposes.

Automation: APIs enable process automation and workflow optimization by providing access to data and functionality from multiple applications.

CRM integration: APIs enable the integration of customer relationship management (CRM) systems with other applications to provide a comprehensive view of customer activity. They can also help automate sales and marketing processes by enabling data exchange between CRM platforms and email marketing, lead generation or analytics tools.

ERP connectivity: APIs can streamline communication between enterprise resource planning (ERP) systems and other applications in the enterprise. They enable data exchange and automation of processes in finance, procurement, inventory management, manufacturing and distribution.

MDM integration: The integration of Master Data Management (MDM) systems via APIs enables the central management and maintenance of master data. These can also be used to synchronize data between different systems and platforms to ensure data quality and consistency.

Risk Management: In risk management, APIs can be used to identify, assess and manage risks. They can enable the integration of risk management solutions with other systems to provide real-time information about risks such as credit or market risks and meet compliance requirements.

B2B Communication: APIs facilitate communication and collaboration between companies by enabling the exchange of data and information about supply chains, purchase orders, invoices, and product catalogs. This helps to increase efficiency and reduce costs.

Business Intelligence: In B2B, APIs can help improve decision-making by providing access to data from various internal and external sources. This helps companies make better business decisions by accessing real-time information and analytics.

What is the latency of an API?

Definition: Latency refers to the time delay between sending a request to an API and receiving a response. Low latency is critical for a fast and responsive application experience.

Influencing Factors: The latency of an API can be affected by a number of factors, including network connectivity, server performance, application architecture, and request complexity.

Synchronous and asynchronous API integration

Synchronous: In synchronous API requests, the client waits for the response before performing any further actions. This means that the client is blocked until the API returns the response. Synchronous behavior is suitable for applications that need an immediate response to proceed.

Asynchronous: Asynchronous API requests allow the client to perform other actions while waiting for a response. This allows for more efficient resource usage and better scalability. Asynchronous APIs are especially useful when the API response time is long or the client needs to handle multiple requests in parallel.

Unidirectional and bidirectional API integration

Unidirectional: In unidirectional APIs, communication is one-way, either from the client to the server or vice versa. An example of unidirectional communication is a client simply retrieving data from a server without the server receiving or expecting additional information from the client.

Bidirectional: Bidirectional APIs allow communication in both directions between client and server. This allows the exchange of information and collaboration between the two parties. Bidirectional APIs can be used for applications that require real-time updates or continuous interactions, such as chat applications or collaborative editing tools.

API security

Authentication: Authentication methods are used to ensure that only authorized users can access an API. A common approach is to use API keys, tokens, or OAuth to identify and authorize users and applications.

Encryption: Data transfer between client and API server should be protected by encryption to prevent data leakage and man-in-the-middle attacks. HTTPS (Hypertext Transfer Protocol Secure) is a standard protocol that secures communication between client and server using SSL/TLS encryption.

Access Control: Fine-grained access control is important to ensure that users and applications can only access resources relevant to their role and permissions. APIs should provide the ability to define and enforce role- and user-based access restrictions.

Monitoring and logging: To detect and investigate security incidents, API servers should be monitored and all access to the API should be logged. This enables effective analysis and response to security threats.

API scalability

Load Balancing: To ensure the performance of the API as the number of users or requests increases, the load can be distributed across multiple servers. Load balancers are able to distribute incoming API requests across different servers to optimize response times and avoid bottlenecks.

Caching: Caching is a technique where frequently requested data is cached in order to be able to answer future requests faster. This reduces the load on API servers and improves response times. Caching can be implemented at different levels, such as client, proxy, or server level.

Horizontal and vertical scaling: Horizontal scaling refers to adding additional servers to increase the performance of the API. Vertical scaling, on the other hand, means expanding the capacity of a single server by adding resources such as CPU, memory, or network bandwidth. Both scaling methods can be used to ensure the scalability of an API to meet increasing demands.

Serverless Architecture: Serverless technologies such as AWS Lambda or Azure Functions enable automatic scaling of APIs by automating the provisioning and management of the underlying infrastructure. This architecture can provide a cost-effective solution for APIs that need to dynamically adapt to actual demand.

API Limits

API limits are restrictions set by vendors to control the use of their APIs and ensure system stability and performance. When integrating systems, it is important to consider these limits to avoid issues such as excessive requests, blocked access, or terms of service violations.

Request Rate Limiting: Many API providers limit the number of requests that can be made within a given time period (e.g., per minute or per day). If a client exceeds this limit, further requests may be rejected or delayed.

Concurrency Limit: Some APIs limit the number of concurrent requests a client can make. If this limit is exceeded, further requests may be denied until the number of requests in progress falls below the limit.

Data volume limit: Some APIs place a limit on the amount of data transferred. This can refer to the size of requests, responses, or both. If these limits are exceeded, access to the API can be restricted or blocked.

Use Restrictions: API providers can impose further restrictions on the use of their services, such as the number of resources allowed, the maximum number of API keys, or the types of applications allowed.

To avoid problems integrating systems, developers should:

  1. Check the API documentation and terms of use carefully to be aware of the applicable limits and restrictions.
  2. Implement appropriate mechanisms to ensure limits are met, such as rate limiting, queuing, or caching.
  3. Develop error-handling routines to respond appropriately to limit violations, e.g., by resending requests after a waiting period or notifying the responsible parties.
  4. Monitor API usage to detect potential bottlenecks or limit violations early and respond accordingly.

API documentation

High quality API documentation is critical to the successful use and integration of an API. It provides developers and users with all the information they need to use the API effectively and efficiently. Good API documentation should cover the following aspects:

Overview: An introductory section that describes the API, its features, and its intended use. This section should help users decide if the API is suitable for their needs.

Authentication and Authorization: Clear instructions on authentication and authorization, including registering API keys, using tokens or OAuth, and assigning user roles and permissions.

Endpoints and Methods: A comprehensive list of available API endpoints and associated methods, along with their functions, parameters, and expected return values. This section should also include information about possible error codes and their meaning.

Examples and tutorials: Practical examples and tutorials to help developers quickly and effectively integrate the API into their applications. These can be code snippets in different programming languages, step-by-step tutorials or sample projects.

Limits and Restrictions: Information on applicable API limits and restrictions, such as Request Rate Limit, Concurrency Limit, and Data Volume Limit, as well as guidance on how to handle errors when limits are exceeded.

Version Management and Change History: Information about the current API version and previous versions, as well as a change history to help developers learn about updates and potential impacts to their applications.

Support and Community: Information about available support channels, such as forums, mailing lists, issue trackers, or direct contact with the API vendor. This section should also include links to additional resources such as blog posts, videos, or presentations.

API Monitoring

API monitoring is an important aspect of managing and maintaining APIs. It enables continuous monitoring of an API’s performance, availability, and usage to detect potential problems early and respond to them in a timely manner. Effective API monitoring should include the following components:

Availability: The periodic checking of API endpoints for accessibility and proper function to ensure that the API is available and functioning properly at all times. This can be achieved through periodic health checks or synthetic transactions.

Performance: Monitoring response times, latency, and throughput of the API to detect potential performance bottlenecks or issues early. Performance monitoring should be performed on both the server and client side to get a complete picture of API performance.

Use: Analyzing API usage data to gain insight into user behavior, endpoint or feature popularity, and potential misuse or security risks. This can be done by analyzing log files or integrating analytics tools.

Error monitoring: The detection and analysis of errors that occur while using the API to determine their causes and take appropriate corrective action. Error monitoring should include information about error codes, exceptions, and error messages.

Notifications and alarms: Setting up notifications and alarms that are automatically triggered when predefined thresholds or conditions are exceeded. This enables rapid response to issues and helps minimize the impact on users and systems.

API Monitoring helps developers and operators ensure the quality and reliability of their APIs, proactively identify potential issues, and implement continuous improvements based on usage data and performance metrics.

API Logging

Logging is an essential part of API management and is used to record information about API requests, responses, and internal operations. By collecting and analyzing log data, developers and operators can gain valuable insight into how the API is working, potential problems, and opportunities for improvement. An effective logging strategy should consider the following aspects:

Requests and responses: Logging API requests and responses, including the endpoints, methods, parameters, headers and payloads used. This enables tracking of user actions, analysis of data flow, and identification of anomalies or errors.

Performance Metrics: The collection of performance metrics such as response times, latency, and throughput to monitor API performance over time and identify trends or bottlenecks.

Errors and Exceptions: The logging of errors and exceptions that occur when using the API, including error codes, error messages, and stack traces. This helps developers identify the root causes of problems and implement appropriate solutions.

Security events: The recording of security-related events such as authentication attempts, access violations, or suspicious activities to identify potential security risks early and take appropriate countermeasures.

Contextual Information: The collection of contextual information such as user IDs, API keys, or IP addresses to enable tracking of user activity and attribution of events to specific users or systems.

iPaaS ( Integration Platform) and API Integration

Integration Platform as a Service (iPaaS) is a cloud-based solution that enables APIs and other applications to be seamlessly connected to share data and functionality and automate business processes. iPaaS solutions vary in their feature set, ease of use, and use cases, but all provide tools and services for fast and efficient API integration.

Some of the key differences between various iPaaS offerings include.

  • Number of APIs and integrations supported
  • Availability of pre-built connectors or adapters
  • Flexibility in customizing and extending integrations
  • Ease of use and learning curve for developers and non-developers
  • Scalability and performance to meet different requirements
  • Security features such as encryption, authentication, and access control

The Marini Integration Platform is a best-of-breed iPaaS solution that features comprehensive support for a wide range of APIs and endpoints. Designed to provide both security and scalability, it meets the demanding needs of modern enterprises. In addition, users benefit from an intuitive user interface that simplifies getting started and working with the platform and enables efficient implementation of integrations. Through this combination of powerful functionality and ease of use, the Marini Integration Platform offers compelling value to enterprises looking for a reliable and efficient solution for their API integrations.

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