Merge pull request #212 from zzxwill/log

Implement `vela logs`

cmd/vela/main.go

@@ -122,6 +122,8 @@ func newCommand() *cobra.Command {
 		cmd.NewWorkloadsCommand(ioStream),
 
 		cmd.NewDashboardCommand(commandArgs, ioStream),
+
+		cmd.NewLogsCommand(commandArgs, ioStream),
 	)
 
 	// Traits

go.mod

@@ -4,6 +4,7 @@ go 1.13
 
 require (
 	cuelang.org/go v0.2.2
+	github.com/Azure/go-autorest v12.2.0+incompatible // Don't remove. https://github.com/kubernetes/client-go/issues/628
 	github.com/coreos/prometheus-operator v0.41.1
 	github.com/crossplane/crossplane-runtime v0.9.0
 	github.com/crossplane/oam-kubernetes-runtime v0.0.9
@@ -14,7 +15,6 @@ require (
 	github.com/google/go-cmp v0.5.2
 	github.com/google/go-github/v32 v32.1.0
 	github.com/gosuri/uitable v0.0.4
-	github.com/oam-dev/catalog/traits/metricstrait v0.0.0-20200826071236-d96c1d64e221
 	github.com/onsi/ginkgo v1.11.0
 	github.com/onsi/gomega v1.8.1
 	github.com/pkg/errors v0.9.1
@@ -22,6 +22,7 @@ require (
 	github.com/spf13/cobra v1.0.0
 	github.com/spf13/pflag v1.0.5
 	github.com/stretchr/testify v1.6.1
+	github.com/wercker/stern v0.0.0-20190705090245-4fa46dd6987f
 	go.uber.org/zap v1.13.0
 	golang.org/x/oauth2 v0.0.0-20200107190931-bf48bf16ab8d
 	gopkg.in/natefinch/lumberjack.v2 v2.0.0
@@ -33,11 +34,15 @@ require (
 	k8s.io/cli-runtime v0.18.6
 	k8s.io/client-go v12.0.0+incompatible
 	k8s.io/klog v1.0.0
+	k8s.io/kube-openapi v0.0.0-20200410145947-bcb3869e6f29 // indirect
 	k8s.io/kubectl v0.18.6 // indirect
 	k8s.io/utils v0.0.0-20200414100711-2df71ebbae66
 	rsc.io/letsencrypt v0.0.3 // indirect
 	sigs.k8s.io/controller-runtime v0.6.0
 )
 
-// clint-go had a buggy release, https://github.com/kubernetes/client-go/issues/749
-replace k8s.io/client-go => k8s.io/client-go v0.18.6
+replace (
+	github.com/wercker/stern => github.com/oam-dev/stern v1.13.0-alpha
+	// clint-go had a buggy release, https://github.com/kubernetes/client-go/issues/749
+	k8s.io/client-go => k8s.io/client-go v0.18.6
+)

go.sum

@@ -14,6 +14,7 @@ cloud.google.com/go v0.50.0/go.mod h1:r9sluTvynVuxRIOHXQEHMFffphuXHOMZMycpNR5e6T
 cloud.google.com/go v0.51.0/go.mod h1:hWtGJ6gnXH+KgDv+V0zFGDvpi07n3z8ZNj3T1RW0Gcw=
 cloud.google.com/go v0.52.0/go.mod h1:pXajvRH/6o3+F9jDHZWQ5PbGhn+o8w9qiu/CffaVdO4=
 cloud.google.com/go v0.53.0/go.mod h1:fp/UouUEsRkN6ryDKNW/Upv/JBKnv6WDthjR6+vze6M=
+cloud.google.com/go v0.56.0 h1:WRz29PgAsVEyPSDHyk+0fpEkwEFyfhHn+JbksT6gIL4=
 cloud.google.com/go v0.56.0/go.mod h1:jr7tqZxxKOVYizybht9+26Z/gUq7tiRzu+ACVAMbKVk=
 cloud.google.com/go/bigquery v1.0.1/go.mod h1:i/xbL2UlR5RvWAURpBYZTtm/cXjCha9lbfbpx4poX+o=
 cloud.google.com/go/bigquery v1.3.0/go.mod h1:PjpwJnslEMmckchkHFfq+HTD2DmtT67aNFKH1/VBDHE=
@@ -43,28 +44,39 @@ github.com/Azure/azure-sdk-for-go v43.0.0+incompatible/go.mod h1:9XXNKU+eRnpl9mo
 github.com/Azure/azure-storage-blob-go v0.8.0/go.mod h1:lPI3aLPpuLTeUwh1sViKXFxwl2B6teiRqI0deQUvsw0=
 github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78 h1:w+iIsaOQNcT7OZ575w+acHgRric5iCyQh+xv+KJ4HB8=
 github.com/Azure/go-ansiterm v0.0.0-20170929234023-d6e3b3328b78/go.mod h1:LmzpDX56iTiv29bbRTIsUNlaFfuhWRQBWjQdVyAevI8=
+github.com/Azure/go-autorest v10.8.1+incompatible h1:u0jVQf+a6k6x8A+sT60l6EY9XZu+kHdnZVPAYqpVRo0=
 github.com/Azure/go-autorest v10.8.1+incompatible/go.mod h1:r+4oMnoxhatjLLJ6zxSWATqVooLgysK6ZNox3g/xq24=
 github.com/Azure/go-autorest v11.2.8+incompatible/go.mod h1:r+4oMnoxhatjLLJ6zxSWATqVooLgysK6ZNox3g/xq24=
+github.com/Azure/go-autorest v12.2.0+incompatible h1:2Fxszbg492oAJrcvJlgyVaTqnQYRkxmEK6VPCLLVpBI=
+github.com/Azure/go-autorest v12.2.0+incompatible/go.mod h1:r+4oMnoxhatjLLJ6zxSWATqVooLgysK6ZNox3g/xq24=
 github.com/Azure/go-autorest/autorest v0.9.0/go.mod h1:xyHB1BMZT0cuDHU7I0+g046+BFDTQ8rEZB0s4Yfa6bI=
+github.com/Azure/go-autorest/autorest v0.9.2 h1:6AWuh3uWrsZJcNoCHrCF/+g4aKPCU39kaMO6/qrnK/4=
 github.com/Azure/go-autorest/autorest v0.9.2/go.mod h1:xyHB1BMZT0cuDHU7I0+g046+BFDTQ8rEZB0s4Yfa6bI=
 github.com/Azure/go-autorest/autorest v0.9.3-0.20191028180845-3492b2aff503/go.mod h1:xyHB1BMZT0cuDHU7I0+g046+BFDTQ8rEZB0s4Yfa6bI=
 github.com/Azure/go-autorest/autorest v0.10.0/go.mod h1:/FALq9T/kS7b5J5qsQ+RSTUdAmGFqi0vUdVNNx8q630=
+github.com/Azure/go-autorest/autorest v0.10.2 h1:NuSF3gXetiHyUbVdneJMEVyPUYAe5wh+aN08JYAf1tI=
 github.com/Azure/go-autorest/autorest v0.10.2/go.mod h1:/FALq9T/kS7b5J5qsQ+RSTUdAmGFqi0vUdVNNx8q630=
 github.com/Azure/go-autorest/autorest/adal v0.5.0/go.mod h1:8Z9fGy2MpX0PvDjB1pEgQTmVqjGhiHBW7RJJEciWzS0=
+github.com/Azure/go-autorest/autorest/adal v0.8.0 h1:CxTzQrySOxDnKpLjFJeZAS5Qrv/qFPkgLjx5bOAi//I=
 github.com/Azure/go-autorest/autorest/adal v0.8.0/go.mod h1:Z6vX6WXXuyieHAXwMj0S6HY6e6wcHn37qQMBQlvY3lc=
 github.com/Azure/go-autorest/autorest/adal v0.8.1-0.20191028180845-3492b2aff503/go.mod h1:Z6vX6WXXuyieHAXwMj0S6HY6e6wcHn37qQMBQlvY3lc=
 github.com/Azure/go-autorest/autorest/adal v0.8.2/go.mod h1:ZjhuQClTqx435SRJ2iMlOxPYt3d2C/T/7TiQCVZSn3Q=
+github.com/Azure/go-autorest/autorest/adal v0.8.3 h1:O1AGG9Xig71FxdX9HO5pGNyZ7TbSyHaVg+5eJO/jSGw=
 github.com/Azure/go-autorest/autorest/adal v0.8.3/go.mod h1:ZjhuQClTqx435SRJ2iMlOxPYt3d2C/T/7TiQCVZSn3Q=
 github.com/Azure/go-autorest/autorest/date v0.1.0/go.mod h1:plvfp3oPSKwf2DNjlBjWF/7vwR+cUD/ELuzDCXwHUVA=
+github.com/Azure/go-autorest/autorest/date v0.2.0 h1:yW+Zlqf26583pE43KhfnhFcdmSWlm5Ew6bxipnr/tbM=
 github.com/Azure/go-autorest/autorest/date v0.2.0/go.mod h1:vcORJHLJEh643/Ioh9+vPmf1Ij9AEBM5FuBIXLmIy0g=
 github.com/Azure/go-autorest/autorest/mocks v0.1.0/go.mod h1:OTyCOPRA2IgIlWxVYxBee2F5Gr4kF2zd2J5cFRaIDN0=
 github.com/Azure/go-autorest/autorest/mocks v0.2.0/go.mod h1:OTyCOPRA2IgIlWxVYxBee2F5Gr4kF2zd2J5cFRaIDN0=
+github.com/Azure/go-autorest/autorest/mocks v0.3.0 h1:qJumjCaCudz+OcqE9/XtEPfvtOjOmKaui4EOpFI6zZc=
 github.com/Azure/go-autorest/autorest/mocks v0.3.0/go.mod h1:a8FDP3DYzQ4RYfVAxAN3SVSiiO77gL2j2ronKKP0syM=
 github.com/Azure/go-autorest/autorest/to v0.3.0/go.mod h1:MgwOyqaIuKdG4TL/2ywSsIWKAfJfgHDo8ObuUk3t5sA=
 github.com/Azure/go-autorest/autorest/to v0.3.1-0.20191028180845-3492b2aff503/go.mod h1:MgwOyqaIuKdG4TL/2ywSsIWKAfJfgHDo8ObuUk3t5sA=
 github.com/Azure/go-autorest/autorest/validation v0.2.0/go.mod h1:3EEqHnBxQGHXRYq3HT1WyXAvT7LLY3tl70hw6tQIbjI=
 github.com/Azure/go-autorest/autorest/validation v0.2.1-0.20191028180845-3492b2aff503/go.mod h1:3EEqHnBxQGHXRYq3HT1WyXAvT7LLY3tl70hw6tQIbjI=
+github.com/Azure/go-autorest/logger v0.1.0 h1:ruG4BSDXONFRrZZJ2GUXDiUyVpayPmb1GnWeHDdaNKY=
 github.com/Azure/go-autorest/logger v0.1.0/go.mod h1:oExouG+K6PryycPJfVSxi/koC6LSNgds39diKLz7Vrc=
+github.com/Azure/go-autorest/tracing v0.5.0 h1:TRn4WjSnkcSy5AEG3pnbtFSwNtwzjr4VYyQflFE619k=
 github.com/Azure/go-autorest/tracing v0.5.0/go.mod h1:r/s2XiOKccPW3HrqB+W0TQzfbtp2fGCgRFtBroKn4Dk=
 github.com/BurntSushi/toml v0.3.1 h1:WXkYYl6Yr3qBf1K79EBnL4mak0OimBfB0XUf9Vl28OQ=
 github.com/BurntSushi/toml v0.3.1/go.mod h1:xHWCNGjB5oqiDr8zfno3MHue2Ht5sIBksp03qcyfWMU=
@@ -225,7 +237,6 @@ github.com/coreos/pkg v0.0.0-20160727233714-3ac0863d7acf/go.mod h1:E3G3o1h8I7cfc
 github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f h1:lBNOc5arjvs8E5mO2tbpBpLoyyu8B6e44T7hJy6potg=
 github.com/coreos/pkg v0.0.0-20180928190104-399ea9e2e55f/go.mod h1:E3G3o1h8I7cfcXa63jLwjI0eiQQMgzzUDFVpN/nH/eA=
-github.com/coreos/prometheus-operator v0.40.0/go.mod h1:QOoL5cVI3b1OHgpw8s+pH+Ok4AFRp2HOUvBpqs7UWcg=
 github.com/coreos/prometheus-operator v0.41.1 h1:MEhY9syliPlQg+VlFRUfNodUEVXRXJ2n1pFG0aBp+mI=
 github.com/coreos/prometheus-operator v0.41.1/go.mod h1:LhLfEBydppl7nvfEA1jIqlF3xJ9myHCnzrU+HHDxRd4=
 github.com/cpuguy83/go-md2man v1.0.10 h1:BSKMNlYxDvnunlTymqtgONjNnaRV1sTpcovwwjF22jk=
@@ -239,7 +250,6 @@ github.com/crossplane/crossplane-runtime v0.8.0/go.mod h1:gNY/21MLBaz5KNP7hmfXbB
 github.com/crossplane/crossplane-runtime v0.9.0 h1:K6/tLhXKzhsEUUddTvEWWnQLLrawWyw1ptNK7NBDpDU=
 github.com/crossplane/crossplane-runtime v0.9.0/go.mod h1:gNY/21MLBaz5KNP7hmfXbBXp8reYRbwY5B/97Kp4tgM=
 github.com/crossplane/crossplane-tools v0.0.0-20200219001116-bb8b2ce46330/go.mod h1:C735A9X0x0lR8iGVOOxb49Mt70Ua4EM2b7PGaRPBLd4=
-github.com/crossplane/oam-kubernetes-runtime v0.0.7/go.mod h1:f5xqmo0B2WtaOTZh8jhP+0f0XuzqhJG2xRtxfMZR3jA=
 github.com/crossplane/oam-kubernetes-runtime v0.0.9 h1:cZMT7p1jZ6MsJqAuzVIZwvOxVdD+PGEQgCYHHuwR7Pc=
 github.com/crossplane/oam-kubernetes-runtime v0.0.9/go.mod h1:f5xqmo0B2WtaOTZh8jhP+0f0XuzqhJG2xRtxfMZR3jA=
 github.com/cyphar/filepath-securejoin v0.2.2 h1:jCwT2GTP+PY5nBz3c/YL5PAIbusElVrPujOBSCj8xRg=
@@ -256,6 +266,7 @@ github.com/deislabs/oras v0.8.1/go.mod h1:Mx0rMSbBNaNfY9hjpccEnxkOqJL6KGjtxNHPLC
 github.com/denisenkom/go-mssqldb v0.0.0-20191001013358-cfbb681360f0/go.mod h1:xbL0rPBG9cCiLr28tMa8zpbdarY27NDyej4t/EjAShU=
 github.com/denverdino/aliyungo v0.0.0-20190125010748-a747050bb1ba/go.mod h1:dV8lFg6daOBZbT6/BDGIz6Y3WFGn8juu6G+CQ6LHtl0=
 github.com/dgrijalva/jwt-go v0.0.0-20170104182250-a601269ab70c/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
+github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-bitstream v0.0.0-20180413035011-3522498ce2c8/go.mod h1:VMaSuZ+SZcx/wljOQKvp5srsbCiKDEb6K2wC4+PiBmQ=
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
@@ -315,6 +326,7 @@ github.com/exponent-io/jsonpath v0.0.0-20151013193312-d6023ce2651d h1:105gxyaGwC
 github.com/exponent-io/jsonpath v0.0.0-20151013193312-d6023ce2651d/go.mod h1:ZZMPRZwes7CROmyNKgQzC3XPs6L/G2EJLHddWejkmf4=
 github.com/facette/natsort v0.0.0-20181210072756-2cd4dd1e2dcb/go.mod h1:bH6Xx7IW64qjjJq8M2u4dxNaBiDfKK+z/3eGDpXEQhc=
 github.com/fatih/camelcase v1.0.0/go.mod h1:yN2Sb0lFhZJUdVvtELVWefmrXpuZESvPmqwoZc+/fpc=
+github.com/fatih/color v0.0.0-20180516100307-2d684516a886/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fatih/color v1.7.0 h1:DkWD4oS2D8LGGgTQ6IvwJJXSL5Vp2ffcQg58nFV38Ys=
 github.com/fatih/color v1.7.0/go.mod h1:Zm6kSWBoL9eyXnKyktHP6abPY2pDugNf5KwzbycvMj4=
 github.com/fatih/color v1.9.0 h1:8xPHl4/q1VyqGIPif1F+1V3Y3lSmrq01EabUW3CoW5s=
@@ -776,6 +788,8 @@ github.com/mattn/go-colorable v0.1.2/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVc
 github.com/mattn/go-colorable v0.1.4/go.mod h1:U0ppj6V5qS13XJ6of8GYAs25YV2eR4EVcfRqFIhoBtE=
 github.com/mattn/go-colorable v0.1.6 h1:6Su7aK7lXmJ/U79bYtBjLNaha4Fs1Rg9plHpcH+vvnE=
 github.com/mattn/go-colorable v0.1.6/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
+github.com/mattn/go-colorable v0.1.7 h1:bQGKb3vps/j0E9GfJQ03JyhRuxsvdAanXlT9BTw3mdw=
+github.com/mattn/go-colorable v0.1.7/go.mod h1:u6P/XSegPjTcexA+o6vUJrdnUu04hMope9wVRipJSqc=
 github.com/mattn/go-ieproxy v0.0.0-20190610004146-91bb50d98149/go.mod h1:31jz6HNzdxOmlERGGEc4v/dMssOfmp2p5bT/okiKFFc=
 github.com/mattn/go-ieproxy v0.0.0-20190702010315-6dee0af9227d/go.mod h1:31jz6HNzdxOmlERGGEc4v/dMssOfmp2p5bT/okiKFFc=
 github.com/mattn/go-ieproxy v0.0.0-20191113090002-7c0f6868bffe/go.mod h1:pYabZ6IHcRpFh7vIaLfK7rdcWgFEb3SFJ6/gNWuh88E=
@@ -811,7 +825,9 @@ github.com/minio/sha256-simd v0.1.1/go.mod h1:B5e1o+1/KgNmWrSQK08Y6Z1Vb5pwIktudl
 github.com/mitchellh/cli v1.0.0/go.mod h1:hNIlj7HEI86fIcpObd7a0FcrxTWetlwJDGcceTlRvqc=
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+github.com/mitchellh/go-homedir v0.0.0-20161203194507-b8bc1bf76747/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/go-homedir v1.0.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
+github.com/mitchellh/go-homedir v1.1.0 h1:lukF9ziXFxDFPkA1vsr5zpc1XuPDn/wFntq5mG+4E0Y=
 github.com/mitchellh/go-homedir v1.1.0/go.mod h1:SfyaCUpYCn1Vlf4IUYiD9fPX4A5wJrkLzIz1N1q0pr0=
 github.com/mitchellh/go-testing-interface v1.0.0/go.mod h1:kRemZodwjscx+RGhAo8eIhFbs2+BFgRtFPeD/KE+zxI=
 github.com/mitchellh/go-wordwrap v1.0.0 h1:6GlHJ/LTGMrIJbwgdqdl2eEH8o+Exx/0m8ir9Gns0u4=
@@ -854,8 +870,8 @@ github.com/nats-io/nkeys v0.1.0/go.mod h1:xpnFELMwJABBLVhffcfd1MZx6VsNRFpEugbxzi
 github.com/nats-io/nkeys v0.1.3/go.mod h1:xpnFELMwJABBLVhffcfd1MZx6VsNRFpEugbxziKVo7w=
 github.com/nats-io/nuid v1.0.1/go.mod h1:19wcPz3Ph3q0Jbyiqsd0kePYG7A95tJPxeL+1OSON2c=
 github.com/ncw/swift v1.0.47/go.mod h1:23YIA4yWVnGwv2dQlN4bB7egfYX6YLn0Yo/S6zZO/ZM=
-github.com/oam-dev/catalog/traits/metricstrait v0.0.0-20200826071236-d96c1d64e221 h1:wrk8i7z7D7/b6D1oukv+sV9DOhmqZIbiwFTqIe6aQ4w=
-github.com/oam-dev/catalog/traits/metricstrait v0.0.0-20200826071236-d96c1d64e221/go.mod h1:mpYuuccw79F/yddIODjdDCzUyvXNnuksPWVx/z5vZBw=
+github.com/oam-dev/stern v1.13.0-alpha h1:EVjM8Qvh6LssB6t4RZrjf9DtCq1cz+/cy6OF7fpy9wk=
+github.com/oam-dev/stern v1.13.0-alpha/go.mod h1:AOkvfFUv0Arz7GBi0jz7S0Jsu4K/kdvSjNsnRt1+BIg=
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 github.com/oklog/run v1.1.0/go.mod h1:sVPdnTZT1zYwAJeCMu2Th4T21pA3FPOQRfWjQlk7DVU=
@@ -920,6 +936,7 @@ github.com/phayes/freeport v0.0.0-20180830031419-95f893ade6f2/go.mod h1:iIss55rK
 github.com/philhofer/fwd v1.0.0/go.mod h1:gk3iGcWd9+svBvR0sR+KPcfE+RNWozjowpeBVG3ZVNU=
 github.com/pierrec/lz4 v1.0.2-0.20190131084431-473cd7ce01a1/go.mod h1:3/3N9NVKO0jef7pBehbT1qWhCMrIgbYNnFAZCqQ5LRc=
 github.com/pierrec/lz4 v2.0.5+incompatible/go.mod h1:pdkljMzZIN41W+lC3N2tnIh5sFi+IEE17M5jbnwPHcY=
+github.com/pkg/errors v0.0.0-20180311214515-816c9085562c/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1-0.20171018195549-f15c970de5b7/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
@@ -1058,6 +1075,7 @@ github.com/spf13/afero v1.2.2/go.mod h1:9ZxEEn6pIJ8Rxe320qSDBk6AsU0r9pR7Q4OcevTd
 github.com/spf13/cast v1.3.0/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
 github.com/spf13/cast v1.3.1 h1:nFm6S0SMdyzrzcmThSipiEubIDy8WEXKNZ0UOgiRpng=
 github.com/spf13/cast v1.3.1/go.mod h1:Qx5cxh0v+4UWYiBimWS+eyWzqEqokIECu5etghLkUJE=
+github.com/spf13/cobra v0.0.0-20180629152535-a114f312e075/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.2-0.20171109065643-2da4a54c5cee/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.3/go.mod h1:1l0Ry5zgKvJasoi3XT1TypsSe7PqH0Sj9dhYf7v3XqQ=
 github.com/spf13/cobra v0.0.5 h1:f0B+LkLX6DtmRH1isoNA9VTtNUK9K8xYd28JNNfOv/s=
@@ -1364,6 +1382,8 @@ golang.org/x/sys v0.0.0-20200122134326-e047566fdf82/go.mod h1:h1NjWce9XRLGQEsW7w
 golang.org/x/sys v0.0.0-20200124204421-9fbb57f87de9/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200202164722-d101bd2416d5/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200212091648-12a6c2dcc1e4/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
+golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae h1:/WDfKMnPU+m5M4xB+6x4kaepxRw6jWvR5iDRdvjHgy8=
+golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200223170610-d5e6a3e2c0ae/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200323222414-85ca7c5b95cd/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=
 golang.org/x/sys v0.0.0-20200331124033-c3d80250170d/go.mod h1:h1NjWce9XRLGQEsW7wpKNCjG9DtNlClVuFLEZdDNbEs=

pkg/cmd/logs.go

@@ -0,0 +1,112 @@
+package cmd
+
+import (
+	"context"
+
+	"github.com/wercker/stern/kubernetes"
+
+	"github.com/cloud-native-application/rudrx/api/types"
+	cmdutil "github.com/cloud-native-application/rudrx/pkg/cmd/util"
+	"github.com/spf13/cobra"
+	sternCmd "github.com/wercker/stern/cmd"
+	"github.com/wercker/stern/stern"
+)
+
+func NewLogsCommand(c types.Args, ioStreams cmdutil.IOStreams) *cobra.Command {
+	cmd := &cobra.Command{}
+	cmd.Use = "logs <appname>"
+	cmd.Short = "Tail pods logs of an application"
+	cmd.Long = "Tail pods logs of an application"
+	cmd.PreRunE = func(cmd *cobra.Command, args []string) error {
+		if len(args) < 1 {
+			ioStreams.Errorf("please specify the application name")
+		}
+		appName := args[0]
+		cmd.SetArgs([]string{appName + ".*"})
+		env, err := GetEnv(cmd)
+		if err != nil {
+			return err
+		}
+		namespace := env.Namespace
+		cmd.Flags().String("namespace", namespace, "")
+		return nil
+	}
+	cmd.RunE = func(cmd *cobra.Command, args []string) error {
+		config, err := sternCmd.ParseConfig(args)
+		if err != nil {
+			return err
+		}
+		ctx := context.Background()
+		if err := Run(ctx, config, ioStreams); err != nil {
+			return err
+		}
+		return nil
+	}
+	cmd.Annotations = map[string]string{
+		types.TagCommandType: types.TypeApp,
+	}
+	return cmd
+}
+
+// Run refer to the implementation at https://github.com/oam-dev/stern/blob/master/stern/main.go
+func Run(ctx context.Context, config *stern.Config, ioStreams cmdutil.IOStreams) error {
+	clientConfig := kubernetes.NewClientConfig(config.KubeConfig, config.ContextName)
+	clientSet, err := kubernetes.NewClientSet(clientConfig)
+	if err != nil {
+		return err
+	}
+	namespace := config.Namespace
+	added, removed, err := stern.Watch(ctx, clientSet.CoreV1().Pods(namespace), config.PodQuery, config.ContainerQuery, config.ExcludeContainerQuery, config.ContainerState, config.LabelSelector)
+	if err != nil {
+		return err
+	}
+	tails := make(map[string]*stern.Tail)
+	logC := make(chan string, 1024)
+
+	go func() {
+		for {
+			select {
+			case str := <-logC:
+				ioStreams.Infonln(str)
+			case <-ctx.Done():
+				break
+			}
+		}
+	}()
+
+	go func() {
+		for p := range added {
+			id := p.GetID()
+			if tails[id] != nil {
+				continue
+			}
+
+			tail := stern.NewTail(p.Namespace, p.Pod, p.Container, config.Template, &stern.TailOptions{
+				Timestamps:   config.Timestamps,
+				SinceSeconds: int64(config.Since.Seconds()),
+				Exclude:      config.Exclude,
+				Include:      config.Include,
+				Namespace:    config.AllNamespaces,
+				TailLines:    config.TailLines,
+			})
+			tails[id] = tail
+
+			tail.Start(ctx, clientSet.CoreV1().Pods(p.Namespace), logC)
+		}
+	}()
+
+	go func() {
+		for p := range removed {
+			id := p.GetID()
+			if tails[id] == nil {
+				continue
+			}
+			tails[id].Close()
+			delete(tails, id)
+		}
+	}()
+
+	<-ctx.Done()
+
+	return nil
+}

pkg/cmd/util/cmd.go

@@ -36,6 +36,11 @@ func NewTestIOStreams() (IOStreams, *bytes.Buffer, *bytes.Buffer, *bytes.Buffer)
 	}, in, out, errOut
 }
 
+//Infonln compared to Info(), won't print new line
+func (i *IOStreams) Infonln(a ...interface{}) {
+	i.Out.Write([]byte(fmt.Sprint(a...)))
+}
+
 func (i *IOStreams) Info(a ...interface{}) {
 	i.Out.Write([]byte(fmt.Sprintln(a...)))
 }