Design versioning strategy for MSI pre-release & fix the MSI generator script

[liliankasem]

MSI versioning is limited to x.x.x (major.minor.build) and as such does not support pre-release versions, or semver standards.

Today, the MSI script is broken as it assumes MSI versioning allows 4 numbers (x.x.x.x):

azure-functions-core-tools/eng/scripts/generate-msi-files.ps1

Lines 66 to 67 in 78afd8b

	# If the version has -ci.x.y, convert it to .x to ensure we have a valid MSI version format
	$cliVersion = $cliVersion -replace '-(?:ci|beta|rc|dev)\.([0-9]+)\.0$', '.$1'

(It also doensn't support the -preview suffix but that's besides the point)

This hasn't been an issue so far as we have never released a preview MSI package before, however if we ever intend to in future, this issue needs to be addressed before hand.

Tasks

• Design a versioning approach that supports pre-release versioning

An potential solution could be using the ado build number for all MSI versions (as suggested by the MSI version docs e.g. 4.3.235164), never including patch. Or designing a schema such as this one.

• Update the generate-msi-files.ps1 to adhear to the new versioning standard

If we decide that we do not want to ever support MSI pre-releases (that's also fine as we have many other release channels), we should at the very least fix the current msi generator script to ensure a valid MSI version when any suffix is included.

[liliankasem]

I was looking at a recent internal build of the MSI packages and it looks like x.x.x.x is supported?

# CLI semver version: 4.2.2-ci.25429.0

CLI version not provided, attempting to extract from artifacts path...
CLI Version: 4.2.2.25429

Processing platform: x64 in directory: D:\a\_work\1\staging\func-cli\Azure.Functions.Cli.win-x64.4.2.2-ci.25429.0

Successfully created: D:\a\_work\1/staging/func-cli\func-cli-4.2.2.25429-x64.msi
MSI generation completed for platforms: x64

If that is the case, we can use the last number for revision and every version released will just increment this by +1

4.2.2-preview1 -> 4.2.2.1
4.2.2-preview2 -> 4.2.2.2
4.2.2 -> 4.2.2.3

or we can use the buildid