Difference between SOAP, REST, ODATA and HTTP protocols

Advantages, Disadvantages and Differences between Widely-Used Web Service Communication Message Protocols

HTTP, SOAP, REST-ODATA.

All these are important Web Services term but how they work and what applications/businesses use these for communication creates the fine line between its advantages, disadvantages and usage.

Understand the overview and the differences between SOAP, REST, ODATA and HTTP protocols.

Simple Object Access Protocol (SOAP)

SOAP – works on XML only

• Used mainly to perform operation like Change Service Notification, Create New Hire, POST back updates etc.
• Slightly difficult to read and parse due to complex XML format, slightly slower than REST - Easier to build
• WS-security can be used extensively
• It has an extensive support for ACID based transaction management for short-lived transactions and compensation based transaction management for long-running transactions.
• JAX-WS is the java API for SOAP. SOAP APIs are convenient with JavaScript but don't support for greater implementation.
• SOAP use service interface to expose the business logic.
  
  
  

SOAP XML message Request -

Representational State Transfer (REST)

REST – works on plain text, HTML, XML, JSON, YAML, and others.

• Used mainly to interact with a data source, for example retrieving data for all the products > 10Easier to parse so comparably faster than SOAP
• Complex to build compared to SOAP
• WS policy cannot be used as extensively as SOAP, limited to HTTP header security - Useful to consumer APIs
• It is more dynamic, no need to create and update Universal Description, Discovery & Integration (UDDI).
• REST is as standardized as the parts you are using. Security & authentication in HTTP are standardized, so that's what you use when doing REST over HTTP.
• REST is an architectural style and designed for web and network-based software architectures.
• JAX-RS is the java API for REST. REST APIs are convenient with JavaScript & can be implemented easily as well.
• REST use URI to expose business logic.
  
  

JSON POST Message Request -

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Open Data protocol (ODATA)

ODATA is derivative of REST or built on top of it.

• Based on Atom format
• Useful to expose services/APIs
• Based on two main components
• Industry standards: HTTP, XML, Atom and JSON
• REST-based architecture: HTTP protocol
• Support versioning scheme
• It provides facility for extension to achieve custom needs of REST APIs
• It is approved from International Organization for Standardization (ISO) & International Electrotechnical Commission (IEC) for release.
  

ODATA GET message Response -

Conclusion:

SOAP, REST, ODATA and HTTP protocols are the most important current Web service APIs..

HTTP - HTTP is the native transport layer protocol that can carry plain, soap, json or ODATA messages. For simplicity, we can assume it to be the Father of transport protocols with Children like SOAP, REST and ODATA

SOAP API - It is built upon the XML specification & works with the HTTP protocol. That is why it is perfect for usage across the web applications. However, lately companies have started looking at REST/Odata services due to its light wait, extensibility, navigational properties at resource level. SOAP has been there for a while and can be assumed as the eldest son of HTTP family.

SOAP is more suitable for Enterprise Apps requiring high Security, distributed environments like Payments and financial applications.

REST API - While REST APIs were designed to take advantage of existing protocols & used over any protocol, when used for web APIs it typically takes advantage of HTTP. This means that developers have no need to install additional software when creating a REST API. REST is an architectural pattern that ODATA uses as well. Similarly, REST is a step between SOAP and ODATA and can be assumed as the middle child of the HTTP family.

REST is more suitable for Apps requiring moderate security but high scalability for example Social sites like Twitter, Facebook, Instagram etc.

OData - It has been adopted by a lot of companies including SAP, IBM, Salesforce, Tableau, Databoom, Progress, Red Hat and Dell. This is the newest member of the family for data exchange built on architectural pattern of REST. ODATA can be assumed as the youngest child of the HTTP family with newest and greatest capabilities but lacks in wide adoption. Recently, a lot of new APIs are being developed as ODATA only APIs to prepare for the future challenges of scalability and performance.
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