This topic describes how to implement an immediate corrective development, also known as Hotfix.
The best way to handle hotfix situations is to have an environment (e.g. Pre-Production) synchronized with Production, with the same application versions, as well as its data replicated. This way you can test and debug the hotfix and then deploy it to Production, with no downtime. Finally the hotfix is propagated backwards to previous environments (Quality Assurance and Development).
In the following example, it is described how a hotfix is applied to fix a severe bug found in the eCommerce application.
A severe defect was discovered in the eCommerce application in Production and has to be immediately fixed. Proceed as follows:
The version number in Pre-Production has changed: it is suffixed with a '+' (for new changes) and is in red because it is a hotfix.
To apply the hotfix to Production, simply deploy the application from Pre-Production to Production. OutSystems Platform automatically suggests you to choose 'Tag & Deploy 1.7.1'. The hotfix is tagged with a third number in Pre-Production and the application is deployed to Production.
Both Pre-Production and Production have now the 1.7.1 version, and the Pre-Production version is still in red: the hotfix needs to be propagated backwards.
To solve an hotfix, all changes made to the application have to be propagated backwards to all of the previous environments; in this case first to Quality Assurance, and then to Development. Proceed as follows:
The hotfix is solved and there are no more application versions marked in red.
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Deploy to an Environment with Applications with Errors