Replace address resolve with snapshot labels

Previously, the demux-snapshotter had to make an http request to the
http-address-resolver to find the vsock address and metrics
configuration for a remote snapshotter. With this change, the
http-address-resolver is removed and this information is sent to the
demux-snapshotter via snapshot labels directly from the client.

The labels are sent to the demux-snapshotter in the first pepare call
at which point the demux-snapshotter will establish connection with the
remote snapshotter. The connection is then cached via the namespace key
as it was in the previous implementation for subsequent calls.

Since each microVM houses its own remote snapshotter in a clean slate on
boot, any snapshot API call before a prepare will be operating on an empty
snapshotter and therefore will be a noop/not found. Therefore, if we
don't have a connection for an API, we can treat it as the noop/not found
case.

Signed-off-by: Kern Walster <[email protected]>

Author: Kern--

examples/cmd/remote-snapshotter/go.sum

@@ -93,6 +93,7 @@ github.com/PuerkitoBio/purell v1.1.1/go.mod h1:c11w/QuzBsJSee3cPx9rAFu61PvFxuPbt
 github.com/PuerkitoBio/urlesc v0.0.0-20160726150825-5bd2802263f2/go.mod h1:uGdkoq3SwY9Y+13GIhn11/XLaGBb4BfwItxLd5jeuXE=
 github.com/PuerkitoBio/urlesc v0.0.0-20170810143723-de5bf2ad4578/go.mod h1:uGdkoq3SwY9Y+13GIhn11/XLaGBb4BfwItxLd5jeuXE=
 github.com/Shopify/logrus-bugsnag v0.0.0-20171204204709-577dee27f20d/go.mod h1:HI8ITrYtUY+O+ZhtlqUnD8+KwNPOyugEhfP9fdUIaEQ=
+github.com/StackExchange/wmi v0.0.0-20181212234831-e0a55b97c705 h1:UUppSQnhf4Yc6xGxSkoQpPhb7RVzuv5Nb1mwJ5VId9s=
 github.com/StackExchange/wmi v0.0.0-20181212234831-e0a55b97c705/go.mod h1:3eOhrUMpNV+6aFIbp5/iudMxNCF27Vw2OZgy4xEx0Fg=
 github.com/alecthomas/template v0.0.0-20160405071501-a0175ee3bccc/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
 github.com/alecthomas/template v0.0.0-20190718012654-fb15b899a751/go.mod h1:LOuyumcjzFXgccqObfd/Ljyb9UuFJ6TxHnclSeseNhc=
@@ -185,6 +186,7 @@ github.com/containerd/console v0.0.0-20181022165439-0650fd9eeb50/go.mod h1:Tj/on
 github.com/containerd/console v0.0.0-20191206165004-02ecf6a7291e/go.mod h1:8Pf4gM6VEbTNRIT26AyyU7hxdQU3MvAvxVI0sc00XBE=
 github.com/containerd/console v1.0.1/go.mod h1:XUsP6YE/mKtz6bxc+I8UiKKTP04qjQL4qcS3XoQ5xkw=
 github.com/containerd/console v1.0.2/go.mod h1:ytZPjGgY2oeTkAONYafi2kSj0aYggsf8acV1PGKCbzQ=
+github.com/containerd/console v1.0.3 h1:lIr7SlA5PxZyMV30bDW0MGbiOPXwc63yRuCP0ARubLw=
 github.com/containerd/console v1.0.3/go.mod h1:7LqA/THxQ86k76b8c/EMSiaJ3h1eZkMkXar0TQ1gf3U=
 github.com/containerd/containerd v1.2.10/go.mod h1:bC6axHOhabU15QhwfG7w5PipXdVtMXFTttgp+kVtyUA=
 github.com/containerd/containerd v1.3.0-beta.2.0.20190828155532-0293cbd26c69/go.mod h1:bC6axHOhabU15QhwfG7w5PipXdVtMXFTttgp+kVtyUA=
@@ -231,6 +233,7 @@ github.com/containerd/go-runc v0.0.0-20180907222934-5a6d9f37cfa3/go.mod h1:IV7qH
 github.com/containerd/go-runc v0.0.0-20190911050354-e029b79d8cda/go.mod h1:IV7qH3hrUgRmyYrtgEeGWJfWbgcHL9CSRruz2Vqcph0=
 github.com/containerd/go-runc v0.0.0-20200220073739-7016d3ce2328/go.mod h1:PpyHrqVs8FTi9vpyHwPwiNEGaACDxT/N/pLcvMSRA9g=
 github.com/containerd/go-runc v0.0.0-20201020171139-16b287bc67d0/go.mod h1:cNU0ZbCgCQVZK4lgG3P+9tn9/PaJNmoDXPpoJhDR+Ok=
+github.com/containerd/go-runc v1.0.0 h1:oU+lLv1ULm5taqgV/CJivypVODI4SUz1znWjv3nNYS0=
 github.com/containerd/go-runc v1.0.0/go.mod h1:cNU0ZbCgCQVZK4lgG3P+9tn9/PaJNmoDXPpoJhDR+Ok=
 github.com/containerd/imgcrypt v1.0.1/go.mod h1:mdd8cEPW7TPgNG4FpuP3sGBiQ7Yi/zak9TYCG3juvb0=
 github.com/containerd/imgcrypt v1.0.4-0.20210301171431-0ae5c75f59ba/go.mod h1:6TNsg0ctmizkrOgXRNQjAPFWpMYRWuiB6dSF4Pfa5SA=
@@ -352,6 +355,7 @@ github.com/evanphx/json-patch v4.11.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQL
 github.com/evanphx/json-patch v4.12.0+incompatible/go.mod h1:50XU6AFN0ol/bzJsmQLiYLvXMP4fmwYFNcr97nuDLSk=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/felixge/httpsnoop v1.0.1/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
+github.com/firecracker-microvm/firecracker-go-sdk v0.22.1-0.20220427214706-47505a9cf951 h1:j1zRfar/9U22TeptQIwXB07hyuctgb6++HIxP0nXBhI=
 github.com/firecracker-microvm/firecracker-go-sdk v0.22.1-0.20220427214706-47505a9cf951/go.mod h1:60W3x6ftClUbRKpqXl7XvrhM/Uv3tochNRq+RlZsd1M=
 github.com/form3tech-oss/jwt-go v3.2.2+incompatible/go.mod h1:pbq4aXjuKjdthFRnoDwaVPLA+WlJuPGy+QneDUgJi2k=
 github.com/form3tech-oss/jwt-go v3.2.3+incompatible/go.mod h1:pbq4aXjuKjdthFRnoDwaVPLA+WlJuPGy+QneDUgJi2k=
@@ -382,6 +386,7 @@ github.com/go-logr/logr v1.2.1/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbV
 github.com/go-logr/logr v1.2.2/go.mod h1:jdQByPbusPIv2/zmleS9BjJVeZ6kBagPoEUsqbVz/1A=
 github.com/go-logr/stdr v1.2.0/go.mod h1:YkVgnZu1ZjjL7xTxrfm/LLZBfkhTqSR1ydtm6jTKKwI=
 github.com/go-logr/stdr v1.2.2/go.mod h1:mMo/vtBO5dYbehREoey6XUKy/eSumjCCveDpRre4VKE=
+github.com/go-ole/go-ole v1.2.4 h1:nNBDSCOigTSiarFpYE9J/KtEA1IOW4CNeqT9TQDqCxI=
 github.com/go-ole/go-ole v1.2.4/go.mod h1:XCwSNxSkXRo4vlyPy93sltvi/qJq0jqQhjqQNIwKuxM=
 github.com/go-openapi/analysis v0.21.2/go.mod h1:HZwRk4RRisyG8vx2Oe6aqeSQcoxRp47Xkp3+K6q+LdY=
 github.com/go-openapi/errors v0.19.8/go.mod h1:cM//ZKUKyO06HSwqAelJ5NsEMMcpa6VpXe8DOa1Mi1M=
@@ -562,6 +567,7 @@ github.com/hashicorp/consul/api v1.1.0/go.mod h1:VmuI/Lkw1nC05EYQWNKwWGbkg+FbDBt
 github.com/hashicorp/consul/sdk v0.1.1/go.mod h1:VKf9jXwCTEY1QZP2MOLRhb5i/I/ssyNV1vwHyQBF0x8=
 github.com/hashicorp/errwrap v0.0.0-20141028054710-7554cd9344ce/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
 github.com/hashicorp/errwrap v1.0.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
+github.com/hashicorp/errwrap v1.1.0 h1:OxrOeh75EUXMY8TBjag2fzXGZ40LB6IKw45YeGUDY2I=
 github.com/hashicorp/errwrap v1.1.0/go.mod h1:YH+1FKiLXxHSkmPseP+kNlulaMuP3n2brvKWEqk/Jc4=
 github.com/hashicorp/go-cleanhttp v0.5.1/go.mod h1:JpRdi6/HCYpAwUzNwuwqhbovhLtngrth3wmdIIUrZ80=
 github.com/hashicorp/go-hclog v0.9.2/go.mod h1:5CU+agLiy3J7N7QjHK5d05KxGsuXiQLrjA0H7acj2lQ=
@@ -570,6 +576,7 @@ github.com/hashicorp/go-msgpack v0.5.3/go.mod h1:ahLV/dePpqEmjfWmKiqvPkv/twdG7iP
 github.com/hashicorp/go-multierror v0.0.0-20161216184304-ed905158d874/go.mod h1:JMRHfdO9jKNzS/+BTlxCjKNQHg/jZAft8U7LloJvN7I=
 github.com/hashicorp/go-multierror v1.0.0/go.mod h1:dHtQlpGsu+cZNNAkkCN/P3hoUDHhCYQXV3UM06sGGrk=
 github.com/hashicorp/go-multierror v1.1.0/go.mod h1:spPvp8C1qA32ftKqdAHm4hHTbPw+vmowP0z+KUhOZdA=
+github.com/hashicorp/go-multierror v1.1.1 h1:H5DkEtf6CXdFp0N0Em5UCwQpXMWke8IA0+lD48awMYo=
 github.com/hashicorp/go-multierror v1.1.1/go.mod h1:iw975J/qwKPdAO1clOe2L8331t/9/fmwbPZ6JB6eMoM=
 github.com/hashicorp/go-retryablehttp v0.7.0/go.mod h1:vAew36LZh98gCBJNLH42IQ1ER/9wtLZZ8meHqQvEYWY=
 github.com/hashicorp/go-rootcerts v1.0.0/go.mod h1:K6zTfqpRlCUIjkwsN4Z+hiSfzSTQa6eBIzfwKfwNnHU=
@@ -633,10 +640,12 @@ github.com/konsorten/go-windows-terminal-sequences v1.0.3/go.mod h1:T0+1ngSBFLxv
 github.com/kr/logfmt v0.0.0-20140226030751-b84e30acd515/go.mod h1:+0opPa2QZZtGFBFZlji/RkVcI2GknAs/DXo4wKdlNEc=
 github.com/kr/pretty v0.1.0/go.mod h1:dAy3ld7l9f0ibDNOQOHHMYYIIbhfbHSm3C4ZsoJORNo=
 github.com/kr/pretty v0.2.0/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
+github.com/kr/pretty v0.2.1 h1:Fmg33tUaq4/8ym9TJN1x7sLJnHVwhP33CNkpYV/7rwI=
 github.com/kr/pretty v0.2.1/go.mod h1:ipq/a2n7PKx3OHsz4KJII5eveXtPO4qwEXGdVfWzfnI=
 github.com/kr/pty v1.1.1/go.mod h1:pFQYn66WHrOpPYNljwOMqo10TkYh1fy3cYio2l3bCsQ=
 github.com/kr/pty v1.1.5/go.mod h1:9r2w37qlBe7rQ6e1fg1S/9xpWHSnaqNdHD3WcMdbPDA=
 github.com/kr/text v0.1.0/go.mod h1:4Jbv+DJW3UT/LiOwJeYQe1efqtUx/iVham/4vfdArNI=
+github.com/kr/text v0.2.0 h1:5Nx0Ya0ZqY2ygV366QzturHI13Jq95ApcVaJBhpS+AY=
 github.com/kr/text v0.2.0/go.mod h1:eLer722TekiGuMkidMxC/pM04lWEeraHUUmBw8l2grE=
 github.com/kylelemons/godebug v0.0.0-20170820004349-d65d576e9348/go.mod h1:B69LEHPfb2qLo0BaaOLcbitczOKLWTsrBG9LczfCD4k=
 github.com/linuxkit/virtsock v0.0.0-20201010232012-f8cee7dfc7a3/go.mod h1:3r6x7q95whyfWQpmGZTu3gk3v2YkMi05HEzl7Tf7YEo=
@@ -661,9 +670,12 @@ github.com/mattn/go-shellwords v1.0.12/go.mod h1:EZzvwXDESEeg03EKmM+RmDnNOPKG4lL
 github.com/matttproud/golang_protobuf_extensions v1.0.1/go.mod h1:D8He9yQNgCq6Z5Ld7szi9bcBfOoFv/3dc6xSMkL2PC0=
 github.com/matttproud/golang_protobuf_extensions v1.0.2-0.20181231171920-c182affec369/go.mod h1:BSXmuO+STAnVfrANrmjBb36TMTDstsz7MSK+HVaYKv4=
 github.com/maxbrunsfeld/counterfeiter/v6 v6.2.2/go.mod h1:eD9eIE7cdwcMi9rYluz88Jz2VyhSmden33/aXg4oVIY=
+github.com/mdlayher/socket v0.2.0 h1:EY4YQd6hTAg2tcXF84p5DTHazShE50u5HeBzBaNgjkA=
 github.com/mdlayher/socket v0.2.0/go.mod h1:QLlNPkFR88mRUNQIzRBMfXxwKal8H7u1h3bL1CV+f0E=
+github.com/mdlayher/vsock v1.1.1 h1:8lFuiXQnmICBrCIIA9PMgVSke6Fg6V4+r0v7r55k88I=
 github.com/mdlayher/vsock v1.1.1/go.mod h1:Y43jzcy7KM3QB+/FK15pfqGxDMCMzUXWegEfIbSM18U=
 github.com/miekg/dns v1.0.14/go.mod h1:W1PPwlIAgtquWBMBEV9nkV9Cazfe8ScdGz/Lj7v3Nrg=
+github.com/miekg/dns v1.1.25 h1:dFwPR6SfLtrSwgDcIq2bcU/gVutB4sNApq2HBdqcakg=
 github.com/miekg/dns v1.1.25/go.mod h1:bPDLeHnStXmXAq1m/Ch/hvfNHr14JKNPMBo3VZKjuso=
 github.com/miekg/pkcs11 v1.0.3/go.mod h1:XsNlhZGX73bx86s2hdc/FuaLm2CPZJemRLMA+WTFxgs=
 github.com/miekg/pkcs11 v1.1.1/go.mod h1:XsNlhZGX73bx86s2hdc/FuaLm2CPZJemRLMA+WTFxgs=
@@ -848,7 +860,9 @@ github.com/sean-/seed v0.0.0-20170313163322-e2103e2c3529/go.mod h1:DxrIzT+xaE7yg
 github.com/seccomp/libseccomp-golang v0.9.1/go.mod h1:GbW5+tmTXfcxTToHLXlScSlAvWlF4P2Ca7zGrPiEpWo=
 github.com/seccomp/libseccomp-golang v0.9.2-0.20210429002308-3879420cc921/go.mod h1:JA8cRccbGaA1s33RQf7Y1+q9gHmZX1yB/z9WDN1C6fg=
 github.com/seccomp/libseccomp-golang v0.9.2-0.20220502022130-f33da4d89646/go.mod h1:JA8cRccbGaA1s33RQf7Y1+q9gHmZX1yB/z9WDN1C6fg=
+github.com/shirou/gopsutil v2.18.12+incompatible h1:1eaJvGomDnH74/5cF4CTmTbLHAriGFsTZppLXDX93OM=
 github.com/shirou/gopsutil v2.18.12+incompatible/go.mod h1:5b4v6he4MtMOwMlS0TUMTu2PcXUg8+E1lC7eC3UO/RA=
+github.com/shirou/w32 v0.0.0-20160930032740-bb4de0191aa4 h1:udFKJ0aHUL60LboW/A+DfgoHVedieIzIXE8uylPue0U=
 github.com/shirou/w32 v0.0.0-20160930032740-bb4de0191aa4/go.mod h1:qsXQc7+bwAM3Q1u/4XEfrquwF8Lw7D7y5cD8CuHnfIc=
 github.com/shurcooL/sanitized_anchor_name v1.0.0/go.mod h1:1NzhyTcUVG4SuEtjjoZeVRXNmyL/1OwPU0+IJeTBvfc=
 github.com/sirupsen/logrus v1.0.4-0.20170822132746-89742aefa4b2/go.mod h1:pMByvHTf9Beacp5x1UXfOR9xyW/9antXMhjMPG0dEzc=
@@ -990,6 +1004,7 @@ go.uber.org/atomic v1.3.2/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.4.0/go.mod h1:gD2HeocX3+yG+ygLZcrzQJaqmWj9AIm7n08wl/qW/PE=
 go.uber.org/atomic v1.7.0/go.mod h1:fEN4uk6kAWBTFdckzkM89CLk9XfWZrxpCo0nPH17wJc=
 go.uber.org/goleak v1.1.10/go.mod h1:8a7PlsEVH3e/a/GLqe5IIrQx6GzcnRmZEufDUTk4A7A=
+go.uber.org/goleak v1.1.12 h1:gZAh5/EyT/HQwlpkCy6wTpqfH9H8Lz8zbm3dZh+OyzA=
 go.uber.org/goleak v1.1.12/go.mod h1:cwTWslyiVhfpKIDGSZEM2HlOvcqm+tG4zioyIeLoqMQ=
 go.uber.org/multierr v1.1.0/go.mod h1:wR5kodmAFQ0UK8QlbwjlSNy0Z68gJhDJUG5sjR94q/0=
 go.uber.org/multierr v1.6.0/go.mod h1:cdWPpRnG4AhwMwsgIHip0KRBQjJy5kYEpYjJxpXp9iU=
@@ -1014,6 +1029,7 @@ golang.org/x/crypto v0.0.0-20201002170205-7f63de1d35b0/go.mod h1:LzIPMQfyMNhhGPh
 golang.org/x/crypto v0.0.0-20201216223049-8b5274cf687f/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83/go.mod h1:jdWPYTVW3xRLrWPugEBEK3UY2ZEsg3UU495nc5E+M+I=
 golang.org/x/crypto v0.0.0-20210322153248-0c34fe9e7dc2/go.mod h1:T9bdIzuCu7OtxOm1hfPfRQxPLYneinmdGuTeoZ9dtd4=
+golang.org/x/crypto v0.0.0-20210817164053-32db794688a5 h1:HWj/xjIHfjYU5nVXpTM0s39J9CbLn7Cc5a7IC5rwsMQ=
 golang.org/x/crypto v0.0.0-20210817164053-32db794688a5/go.mod h1:GvvjBRRGRdwPK5ydBHafDWAxML/pGHZbMvKqRZ5+Abc=
 golang.org/x/exp v0.0.0-20190121172915-509febef88a4/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
 golang.org/x/exp v0.0.0-20190306152737-a1d7652674e8/go.mod h1:CJ0aWSM057203Lf6IL+f9T1iT9GByDxfZKAQTCR3kQA=
@@ -1480,6 +1496,7 @@ gopkg.in/check.v1 v1.0.0-20141024133853-64131543e789/go.mod h1:Co6ibVJAznAaIkqp8
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20190902080502-41f04d3bba15/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c h1:Hei/4ADfdWqJk1ZMxUNpqntNwaWcugrBjAiHlqqRiVk=
 gopkg.in/check.v1 v1.0.0-20201130134442-10cb98267c6c/go.mod h1:JHkPIbrfpd72SG/EVd6muEfDQjcINNoR0C8j2r3qZ4Q=
 gopkg.in/cheggaaa/pb.v1 v1.0.25/go.mod h1:V/YB90LKu/1FcN3WVnfiiE5oMCibMjukxqG/qStrOgw=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=

examples/cmd/remote-snapshotter/remote_snapshotter.go

@@ -26,6 +26,7 @@ import (
 	fcclient "github.com/firecracker-microvm/firecracker-containerd/firecracker-control/client"
 	"github.com/firecracker-microvm/firecracker-containerd/proto"
 	"github.com/firecracker-microvm/firecracker-containerd/runtime/firecrackeroci"
+	"github.com/firecracker-microvm/firecracker-containerd/snapshotter/demux"
 )
 
 const (
@@ -92,7 +93,7 @@ func main() {
 	defer fcClient.Close()
 
 	fmt.Println("Creating VM")
-	_, err = fcClient.CreateVM(ctx, &proto.CreateVMRequest{
+	vminfo, err := fcClient.CreateVM(ctx, &proto.CreateVMRequest{
 		VMID: vmID,
 		NetworkInterfaces: []*proto.FirecrackerNetworkInterface{{
 			AllowMMDS: true,
@@ -121,10 +122,14 @@ func main() {
 
 	fmt.Println("Pulling the image")
 	image, err := client.Pull(ctx, imageRef,
-		containerd.WithPullSnapshotter(snapshotter),
+		containerd.WithPullSnapshotter(snapshotter,
+			demux.WithVSockPath(vminfo.VSockPath),
+			demux.WithRemoteSnapshotterPort(10000),
+		),
 		containerd.WithPullUnpack,
 		// stargz labels to tell the snapshotter to lazily load the image
-		containerd.WithImageHandlerWrapper(source.AppendDefaultLabelsHandlerWrapper(imageRef, 10*1024*1024)))
+		containerd.WithImageHandlerWrapper(source.AppendDefaultLabelsHandlerWrapper(imageRef, 10*1024*1024)),
+	)
 	if err != nil {
 		fmt.Println(err)
 		return