Atomically write downloaded file to filesystem (#3)

This prevents writing a truncated file to a valid cache path, and
serving that partial file later.

This uses a new dependency, github.com/natefinch/atomic, which from a
quick look seems to do the right thing.

go.mod

@@ -7,7 +7,6 @@ require (
 	github.com/bmatcuk/doublestar/v4 v4.4.0
 	github.com/bwmarrin/discordgo v0.26.1
 	github.com/dustin/go-humanize v1.0.0
-	github.com/google/go-github v17.0.0+incompatible
 	github.com/google/go-github/v48 v48.2.0
 	github.com/hexops/autogold/v2 v2.1.0
 	github.com/hexops/cmder v1.0.1
@@ -16,7 +15,9 @@ require (
 	github.com/keegancsmith/sqlf v1.1.1
 	github.com/manifoldco/promptui v0.9.0
 	github.com/mholt/archiver/v4 v4.0.0-alpha.7
+	github.com/natefinch/atomic v1.0.1
 	github.com/nxadm/tail v1.4.8
+	github.com/wk8/go-ordered-map/v2 v2.1.8
 	golang.org/x/crypto v0.4.0
 	golang.org/x/exp v0.0.0-20221217163422-3c43f8badb15
 	golang.org/x/oauth2 v0.3.0
@@ -53,7 +54,6 @@ require (
 	github.com/remyoudompheng/bigfft v0.0.0-20220927061507-ef77025ab5aa // indirect
 	github.com/therootcompany/xz v1.0.1 // indirect
 	github.com/ulikunitz/xz v0.5.10 // indirect
-	github.com/wk8/go-ordered-map/v2 v2.1.8 // indirect
 	golang.org/x/mod v0.10.0 // indirect
 	golang.org/x/net v0.10.0 // indirect
 	golang.org/x/text v0.9.0 // indirect

go.sum

@@ -20,6 +20,7 @@ github.com/chzyer/test v0.0.0-20180213035817-a1ea475d72b1/go.mod h1:Q3SI9o4m/ZMn
 github.com/chzyer/test v1.0.0 h1:p3BQDXSxOhOG0P9z6/hGnII4LGiEPOYBhs8asl/fC04=
 github.com/chzyer/test v1.0.0/go.mod h1:2JlltgoNkt4TW/z9V/IzDdFaMTM2JPIi26O1pF38GC8=
 github.com/creack/pty v1.1.9/go.mod h1:oKZEueFk5CKHvIhNR5MUki03XCEU+Q6VDXinZuGJ33E=
+github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c=
 github.com/dsnet/compress v0.0.1 h1:PlZu0n3Tuv04TzpfPbrnI0HW/YwodEXDS+oPKahKF0Q=
 github.com/dsnet/compress v0.0.1/go.mod h1:Aw8dCMJ7RioblQeTqt88akK31OvO8Dhf5JflhBbQEHo=
 github.com/dsnet/golib v0.0.0-20171103203638-1ea166775780/go.mod h1:Lj+Z9rebOhdfkVLjJ8T6VcRQv3SXugXy999NBtR9aFY=
@@ -46,8 +47,6 @@ github.com/google/go-cmp v0.5.7/go.mod h1:n+brtR0CgQNWTVd5ZUFpTBC8YFBDLK/h/bpaJ8
 github.com/google/go-cmp v0.5.8/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
 github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
-github.com/google/go-github v17.0.0+incompatible h1:N0LgJ1j65A7kfXrZnUDaYCs/Sf4rEjNlfyDHW9dolSY=
-github.com/google/go-github v17.0.0+incompatible/go.mod h1:zLgOLi98H3fifZn+44m+umXrS52loVEgC2AApnigrVQ=
 github.com/google/go-github/v48 v48.2.0 h1:68puzySE6WqUY9KWmpOsDEQfDZsso98rT6pZcz9HqcE=
 github.com/google/go-github/v48 v48.2.0/go.mod h1:dDlehKBDo850ZPvCTK0sEqTCVWcrGl2LcDiajkYi89Y=
 github.com/google/go-querystring v1.1.0 h1:AnCroh3fv4ZBgVIf1Iwtovgjaw/GiKJo8M8yD/fhyJ8=
@@ -106,6 +105,8 @@ github.com/mattn/go-isatty v0.0.19/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D
 github.com/mattn/go-sqlite3 v1.14.15 h1:vfoHhTN1af61xCRSWzFIWzx2YskyMTwHLrExkBOjvxI=
 github.com/mholt/archiver/v4 v4.0.0-alpha.7 h1:xzByj8G8tj0Oq7ZYYU4+ixL/CVb5ruWCm0EZQ1PjOkE=
 github.com/mholt/archiver/v4 v4.0.0-alpha.7/go.mod h1:Fs8qUkO74HHaidabihzYephJH8qmGD/nCP6tE5xC9BM=
+github.com/natefinch/atomic v1.0.1 h1:ZPYKxkqQOx3KZ+RsbnP/YsgvxWQPGxjC0oBt2AhwV0A=
+github.com/natefinch/atomic v1.0.1/go.mod h1:N/D/ELrljoqDyT3rZrsUmtsuzvHkeB/wWjHV22AZRbM=
 github.com/nightlyone/lockfile v1.0.0 h1:RHep2cFKK4PonZJDdEl4GmkabuhbsRMgk/k3uAmxBiA=
 github.com/nightlyone/lockfile v1.0.0/go.mod h1:rywoIealpdNse2r832aiD9jRk8ErCatROs6LzC841CI=
 github.com/nwaples/rardecode/v2 v2.0.0-beta.2 h1:e3mzJFJs4k83GXBEiTaQ5HgSc/kOK8q0rDaRO0MPaOk=
@@ -122,6 +123,7 @@ github.com/remyoudompheng/bigfft v0.0.0-20220927061507-ef77025ab5aa/go.mod h1:qq
 github.com/rogpeppe/go-internal v1.6.1/go.mod h1:xXDCJY+GAPziupqXw64V24skbSoqbTEfhy4qGm1nDQc=
 github.com/rogpeppe/go-internal v1.9.0/go.mod h1:WtVeX8xhTBvf0smdhujwtBcq4Qrzq/fJaraNFVN+nFs=
 github.com/rogpeppe/go-internal v1.10.0 h1:TMyTOH3F/DB16zRVcYyreMH6GnZZrwQVAoYjRBZyWFQ=
+github.com/stretchr/testify v1.8.1 h1:w7B6lhMri9wdJUVmEZPGGhZzrYTPvgJArz7wNPgYKsk=
 github.com/therootcompany/xz v1.0.1 h1:CmOtsn1CbtmyYiusbfmhmkpAAETj0wBIH6kCYaX+xzw=
 github.com/therootcompany/xz v1.0.1/go.mod h1:3K3UH1yCKgBneZYhuQUvJ9HPD19UEXEI0BWbMn8qNMY=
 github.com/ulikunitz/xz v0.5.6/go.mod h1:2bypXElzHzzJZwzH67Y6wb67pO62Rzfn7BSiF4ABRW8=
@@ -199,6 +201,7 @@ google.golang.org/protobuf v1.26.0/go.mod h1:9q0QmTI4eRPtz6boOQmLYwt+qCgq0jsYwAQ
 google.golang.org/protobuf v1.28.1 h1:d0NfwRgPtno5B1Wa6L2DAG+KivqkdutMf1UhdNx175w=
 google.golang.org/protobuf v1.28.1/go.mod h1:HV8QOd/L58Z+nl8r43ehVNZIU/HEI6OcFqwMG9pJV4I=
 gopkg.in/check.v1 v0.0.0-20161208181325-20d25e280405/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
+gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127 h1:qIbj1fsPNlZgppZ+VLlY7N33q108Sa+fhmuc+sWQYwY=
 gopkg.in/check.v1 v1.0.0-20180628173108-788fd7840127/go.mod h1:Co6ibVJAznAaIkqp8huTwlJQCZ016jof/cbN4VW5Yz0=
 gopkg.in/errgo.v2 v2.1.0/go.mod h1:hNsd1EY+bozCKY1Ytp96fpM3vjJbqLJn88ws8XvfDNI=
 gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7 h1:uRGJdciOHaEIrze2W8Q3AKkepLTh2hOroT7a+7czfdQ=

internal/wrench/http_pkg.go

@@ -4,7 +4,6 @@ import (
 	"context"
 	"encoding/json"
 	"fmt"
-	"io"
 	"net/http"
 	"net/url"
 	"os"
@@ -16,6 +15,7 @@ import (
 
 	"github.com/hexops/wrench/internal/errors"
 	"github.com/hexops/wrench/internal/wrench/scripts"
+	"github.com/natefinch/atomic"
 	orderedmap "github.com/wk8/go-ordered-map/v2"
 )
 
@@ -444,14 +444,9 @@ func (b *Bot) httpPkgEnsureZigDownloadCached(version, versionKind, fname string)
 	if err := os.MkdirAll(dirPath, os.ModePerm); err != nil {
 		return errors.Wrap(err, "MkdirAll "+dirPath)
 	}
-	out, err := os.Create(filePath)
+	err = atomic.WriteFile(filePath, resp.Body)
 	if err != nil {
-		return errors.Wrap(err, "Create "+filePath)
-	}
-	defer out.Close()
-	_, err = io.Copy(out, resp.Body)
-	if err != nil {
-		return errors.Wrap(err, "Copy")
+		return errors.Wrap(err, "Write "+filePath)
 	}
 	return nil
 }