Update minimum Go version

Update minimum required Go version to 1.16 due to use of standard
library package `io/fs`.

Signed-off-by: SuperQ <superq@gmail.com>

Author: SuperQ

.circleci/config.yml

@@ -12,9 +12,9 @@ executors:
   golang:
     docker:
       - image: quay.io/prometheus/golang-builder:1.17-base
-  golang_115:
+  golang_oldest:
     docker:
-      - image: quay.io/prometheus/golang-builder:1.15-base
+      - image: quay.io/prometheus/golang-builder:1.16-base
 
 jobs:
   test_go:
@@ -89,10 +89,11 @@ jobs:
             GOGC: "20"
             GOOPTS: "-p 2"
 
-  test_tsdb_go115:
-    executor: golang_115
+  test_golang_oldest:
+    executor: golang_oldest
     steps:
       - checkout
+      - run: make build
       - run: go test ./tsdb/...
       - run: go test ./tsdb/ -test.tsdb-isolation=false
 
@@ -128,7 +129,7 @@ workflows:
           filters:
             tags:
               only: /.*/
-      - test_tsdb_go115:
+      - test_golang_oldest:
           filters:
             tags:
               only: /.*/

README.md

@@ -56,7 +56,7 @@ Prometheus will now be reachable at http://localhost:9090/.
 ### Building from source
 
 To build Prometheus from source code, You need:
-* Go [version 1.14 or greater](https://golang.org/doc/install).
+* Go [version 1.16 or greater](https://golang.org/doc/install).
 * NodeJS [version 16 or greater](https://nodejs.org/).
 * npm [version 7 or greater](https://www.npmjs.com/).
 

go.mod

@@ -1,6 +1,6 @@
 module github.com/prometheus/prometheus
 
-go 1.14
+go 1.16
 
 require (
 	github.com/Azure/azure-sdk-for-go v60.3.0+incompatible

go.sum

@@ -349,7 +349,6 @@ github.com/cpuguy83/go-md2man/v2 v2.0.0-20190314233015-f79a8a8ca69d/go.mod h1:ma
 github.com/cpuguy83/go-md2man/v2 v2.0.0/go.mod h1:maD7wRr/U5Z6m/iR4s+kqSMx2CaBsrgA7czyZG/E6dU=
 github.com/creack/pty v1.1.7/go.mod h1:lj5s0c3V2DBrqTV7llrYr5NG6My20zk30Fl46Y7DoTY=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
-github.com/creack/pty v1.1.11 h1:07n33Z8lZxZ2qwegKbObQohDhXDQxiMMz1NOUGYlesw=
 github.com/creack/pty v1.1.11/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
 github.com/cyberdelia/templates v0.0.0-20141128023046-ca7fffd4298c/go.mod h1:GyV+0YP4qX0UQ7r2MoYZ+AvYDp12OF5yg4q8rGnyNh4=
 github.com/cyphar/filepath-securejoin v0.2.2/go.mod h1:FpkQEhXnPnOthhzymB7CGsFk2G9VLXONKD9G7QGMM+4=
@@ -1437,7 +1436,6 @@ golang.org/x/exp v0.0.0-20191129062945-2f5052295587/go.mod h1:2RIsYlXP63K8oxa1u0
 golang.org/x/exp v0.0.0-20191227195350-da58074b4299/go.mod h1:2RIsYlXP63K8oxa1u096TMicItID8zy7Y6sNkU49FU4=
 golang.org/x/exp v0.0.0-20200119233911-0405dc783f0a/go.mod h1:2RIsYlXP63K8oxa1u096TMicItID8zy7Y6sNkU49FU4=
 golang.org/x/exp v0.0.0-20200207192155-f17229e696bd/go.mod h1:J/WKrq2StrnmMY6+EHIKF9dgMWnmCNThgcyBT1FY9mM=
-golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6 h1:QE6XYQK6naiK1EPAe1g/ILLxN5RBoH5xkJk3CqlMI/Y=
 golang.org/x/exp v0.0.0-20200224162631-6cc2880d07d6/go.mod h1:3jZMyOhIsHpP37uCMkUooju7aAi5cS1Q23tOzKc+0MU=
 golang.org/x/image v0.0.0-20180708004352-c73c2afc3b81/go.mod h1:ux5Hcp/YLpHSI86hEcLt0YII63i6oz57MZXIpbrjZUs=
 golang.org/x/image v0.0.0-20190227222117-0694c2d4d067/go.mod h1:kZ7UVZpmo3dzQBMxlp+ypCbDeSB+sBbTgSJuh5dn5js=
@@ -1800,10 +1798,8 @@ golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1/go.mod h1:I/5z698sn9Ka8T
 gonum.org/v1/gonum v0.0.0-20180816165407-929014505bf4/go.mod h1:Y+Yx5eoAFn32cQvJDxZx5Dpnq+c3wtXuadVZAcxbbBo=
 gonum.org/v1/gonum v0.0.0-20181121035319-3f7ecaa7e8ca/go.mod h1:Y+Yx5eoAFn32cQvJDxZx5Dpnq+c3wtXuadVZAcxbbBo=
 gonum.org/v1/gonum v0.6.0/go.mod h1:9mxDZsDKxgMAuccQkewq682L+0eCu4dCN2yonUJTCLU=
-gonum.org/v1/gonum v0.8.2 h1:CCXrcPKiGGotvnN6jfUsKk4rRqm7q09/YbKb5xCEvtM=
 gonum.org/v1/gonum v0.8.2/go.mod h1:oe/vMfY3deqTw+1EZJhuvEW2iwGF1bW9wwu7XCu0+v0=
 gonum.org/v1/netlib v0.0.0-20181029234149-ec6d1f5cefe6/go.mod h1:wa6Ws7BG/ESfp6dHfk7C6KdzKA7wR7u/rKwOGE66zvw=
-gonum.org/v1/netlib v0.0.0-20190313105609-8cb42192e0e0 h1:OE9mWmgKkjJyEmDAAtGMPjXu+YNeGvK9VTSHY6+Qihc=
 gonum.org/v1/netlib v0.0.0-20190313105609-8cb42192e0e0/go.mod h1:wa6Ws7BG/ESfp6dHfk7C6KdzKA7wR7u/rKwOGE66zvw=
 gonum.org/v1/plot v0.0.0-20190515093506-e2840ee46a6b/go.mod h1:Wt8AAjI+ypCyYX3nZBvf6cAIx93T+c/OS2HFAYskSZc=
 google.golang.org/api v0.0.0-20160322025152-9bf6e6e569ff/go.mod h1:4mhQ8q/RsB7i+udVvVy5NUi08OU8ZlA0gRVgrF7VFY0=