Move everything over to a more expensive but less collision-prone way.
However, keep the old fingerprinting under the name "FastFingerprint"
to be used in the storage layer (where we need collision detection
anyway).
This fixes https://github.com/prometheus/client_golang/issues/74 .
IT CHANGES THE FINGERPRINTING AND THEREFORE INVALIDATES EACH AND EVERY
PERSISTED FINGERPRINT (I.E. YOU HAVE TO WIPE THE STORAGE TO USE THIS).
This commit removes the LabelValuesToSignature function as it is used
nowhere (and broken in the way it is implemented right now).
Also, remove one more golint warning.
This is actually the intended behavior, and (as a nice side effect)
makes things cheaper to calculate.
Also, introduce a separator character to avoid hash collisions
(like label values {"ab","c"} vs {"a", "bc"}).
Apply the same principles to signature.go.
Change-Id: I607db544f278ed89684fe5fa11abdbc3e03d3061
This rewrite had may backs and forths. In my git repository, it
consists of 35 commits which I cannot group or merge into reasonable
review buckets. Gerrit breaks fundamental git semantics, so I have to
squash the 35 commits into one for the review.
I'll push this not with refs/for/master, but with refs/for/next so
that we can transition after submission in a controlled fashion.
For the review, I recommend to start with looking at godoc and in
particular the many examples. After that, continue with a line-by-line
detailed review. (The big picture is hopefully as expected after
wrapping up the discussion earlier.)
Change-Id: Ib38cc46493a5139ca29d84020650929d94cac850
The LabelsToSignature function is now used outside of the prometheus
package, too. Leaving it in the prometheuos package is misleading
design and will lead to circulat import chains soon.
Change-Id: If1ca442d4023b33b138cf79fee68e82ff2a355be
beorn7