Add access to regexp capturing group Inside URL rewriter #1973
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- add additional level for $tyc_context trigger keys
- $tyk_context.trigger-{n}-{name}-{i}-{groupNum} holds group value
Fixes TykTechnologies#1833
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@buger |
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Nice one! @dencoded can you pls review? |
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Thank you a lot for all changes! @dencoded does it looks good to you? |
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Hi, at this very moment i'm removing repeating/unused code in cached regexp implementation. |
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Better new PR, to separate feature thing from refactoring itself. Thank you! |
mw_url_rewrite.go
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| return strings.Join(parts, triggerKeySep) | ||
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| func addGroupsToContextData(cd *map[string]interface{}, keyPrefix string, groups []string) { |
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you don't need to pass map as pointer as maps (and slices) are passed by reference
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Hmm, for me this one looks suspicious.
Intent of addGroupsToContextData is to modify (add items to) passed map.
As far as i know, in golang everything is value and passed by value (copied). Slices can look like passed by reference, because internally they holds pointer to baking array, first item index, length and capacity.
It can feels like they passed by reference (in case of modifying existing values), but in case of adding items they not. What's why append() returns updated slice.
https://play.golang.org/p/arTxwX1w9mf
I've checked same approach with map and it works, probably because in essence map is just a pointer to underlying structure - i don't know.
Will remove pointers to map as requested
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this is tricky one - slices are different because they have len and cap in addition to pointer to underlaying array with elements, so when we pass it to function it receives new "descriptor" of slice but original pointer to elements.
if we do append inside function we have to return slice and re-assign result on calling side, otherwise calling part will hold slice-descriptor with appended elements but old len and cap (thats why Println outputs only one element). you can find more info about that situation here https://golang.org/doc/effective_go.html#slices
Changing elements would work if your slice is pre-allocated, i.e.:
https://play.golang.org/p/ZoK7WLz_Xtw
That's actually how all functions like func Read(slice []interface{}) (int, error) reading data into passed slice without any explicit pointers.
But my comment was about maps, they work differently.
- extract regexp match handling into function
- add additional level for $tyc_context trigger keys
- $tyk_context.trigger-{n}-{name}-{i}-{groupNum} holds group value
Fixes #1833
- add additional level for $tyc_context trigger keys
- $tyk_context.trigger-{n}-{name}-{i}-{groupNum} holds group value
Fixes #1833
…gies#1973) - add additional level for $tyc_context trigger keys - $tyk_context.trigger-{n}-{name}-{i}-{groupNum} holds group value Fixes TykTechnologies#1833
Fixes #1833