Control plane clients can now perform SVC resolution

[scrye]

If backwards compatibility is desired, speakers with SVC resolution
support can be configured to fall back to using SVC addresses for data
packets.

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This change is 

[oncilla]

Reviewed 18 of 18 files at r1.
Reviewable status: all files reviewed, 5 unresolved discussions (waiting on @scrye)

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go/lib/infra/messenger/addr.go, line 36 at r1 (raw file):

}

// AddressRewriter is used to compute paths and unicast addresses for SVC

This makes it sound like AddressRewriter only computes paths for SVC destinations instead of all destinations.
How about: "AddressRewriter "

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go/lib/infra/messenger/addr.go, line 59 at r1 (raw file):

}

// Rewrite takes address a and adds a path (if one does not already exist but

I do not like the a here, it is weird to read. Plus renaming the parameter could easily out-date the comment.
How about: "Rewrite takes an address and adds"

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go/lib/infra/messenger/addr.go, line 118 at r1 (raw file):

}

// resolveIfSvc returns an UDP/IP address if the input address is an SVC

This should mention what happens if the destination is not an SVC address.

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go/lib/infra/messenger/addr.go, line 169 at r1 (raw file):

}

func getSVC(a addr.HostAddr) addr.HostSVC {

This only introduces an additional function.
The number of if statements is not changed in resolveIfSVC
Just use ok directly.

Added bonus one less occurrence of addr.SvcNone in the code.

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go/lib/infra/messenger/messenger.go, line 110 at r1 (raw file):

	// TrustStore stores and retrieves certificate chains and TRCs.
	TrustStore infra.TrustStore
	// AddressRewriter is used to compute paths and unicast addresses for SVC

this makes it sound like AddressRewriter is only used for SVC destinations.

[scrye]

Reviewable status: all files reviewed, 5 unresolved discussions (waiting on @oncilla)

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go/lib/infra/messenger/addr.go, line 36 at r1 (raw file):

Previously, Oncilla wrote…

This makes it sound like AddressRewriter only computes paths for SVC destinations instead of all destinations.
How about: "AddressRewriter "

Think that's a bit short 😛

Tried to reword it, lemme know what you think.

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go/lib/infra/messenger/addr.go, line 59 at r1 (raw file):

Previously, Oncilla wrote…

I do not like the a here, it is weird to read. Plus renaming the parameter could easily out-date the comment.
How about: "Rewrite takes an address and adds"

Done.

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go/lib/infra/messenger/addr.go, line 118 at r1 (raw file):

Previously, Oncilla wrote…

This should mention what happens if the destination is not an SVC address.

Done.

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go/lib/infra/messenger/addr.go, line 169 at r1 (raw file):

Previously, Oncilla wrote…

This only introduces an additional function.
The number of if statements is not changed in resolveIfSVC
Just use ok directly.

Added bonus one less occurrence of addr.SvcNone in the code.

Done.

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go/lib/infra/messenger/messenger.go, line 110 at r1 (raw file):

Previously, Oncilla wrote…

this makes it sound like AddressRewriter is only used for SVC destinations.

Done.

[oncilla]

Reviewed 2 of 2 files at r2.
Reviewable status: complete! all files reviewed, all discussions resolved

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go/lib/infra/messenger/addr.go, line 36 at r1 (raw file):

Previously, scrye (Sergiu Costea) wrote…

Think that's a bit short 😛

Tried to reword it, lemme know what you think.

Argh, forgot to type there :0
looks good