github.com/meulengracht/snapd@v0.0.0-20210719210640-8bde69bcc84e/overlord/snapstate/catalogrefresh.go (about) 1 // -*- Mode: Go; indent-tabs-mode: t -*- 2 3 /* 4 * Copyright (C) 2017 Canonical Ltd 5 * 6 * This program is free software: you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License version 3 as 8 * published by the Free Software Foundation. 9 * 10 * This program is distributed in the hope that it will be useful, 11 * but WITHOUT ANY WARRANTY; without even the implied warranty of 12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 13 * GNU General Public License for more details. 14 * 15 * You should have received a copy of the GNU General Public License 16 * along with this program. If not, see <http://www.gnu.org/licenses/>. 17 * 18 */ 19 20 package snapstate 21 22 import ( 23 "errors" 24 "fmt" 25 "os" 26 "sort" 27 "strings" 28 "time" 29 30 "github.com/snapcore/snapd/advisor" 31 "github.com/snapcore/snapd/dirs" 32 "github.com/snapcore/snapd/logger" 33 "github.com/snapcore/snapd/osutil" 34 "github.com/snapcore/snapd/overlord/auth" 35 "github.com/snapcore/snapd/overlord/state" 36 "github.com/snapcore/snapd/randutil" 37 "github.com/snapcore/snapd/snapdenv" 38 "github.com/snapcore/snapd/store" 39 "github.com/snapcore/snapd/timings" 40 ) 41 42 var ( 43 catalogRefreshDelayBase = 24 * time.Hour 44 catalogRefreshDelayWithDelta = 24*time.Hour + 1 + randutil.RandomDuration(6*time.Hour) 45 ) 46 47 type catalogRefresh struct { 48 state *state.State 49 50 nextCatalogRefresh time.Time 51 } 52 53 func newCatalogRefresh(st *state.State) *catalogRefresh { 54 return &catalogRefresh{state: st} 55 } 56 57 // Ensure will ensure that the catalog refresh happens 58 func (r *catalogRefresh) Ensure() error { 59 r.state.Lock() 60 defer r.state.Unlock() 61 62 // sneakily don't do anything if in testing 63 if CanAutoRefresh == nil { 64 return nil 65 } 66 67 // if system is not seeded yet, it is first boot situation 68 // do not bother refreshing catalog, snap list is empty anyway 69 // beside there is high change device has no internet 70 var seeded bool 71 err := r.state.Get("seeded", &seeded) 72 if err == state.ErrNoState || !seeded { 73 logger.Debugf("CatalogRefresh:Ensure: skipping refresh, system is not seeded yet") 74 // not seeded yet 75 return nil 76 } 77 78 // similar to the not yet seeded case, on uc20 install mode it doesn't make 79 // sense to refresh the catalog for an ephemeral system 80 deviceCtx, err := DeviceCtx(r.state, nil, nil) 81 if err != nil { 82 // if we are seeded we should have a device context 83 return err 84 } 85 86 if deviceCtx.SystemMode() == "install" { 87 // skip the refresh 88 return nil 89 } 90 91 now := time.Now() 92 delay := catalogRefreshDelayBase 93 if r.nextCatalogRefresh.IsZero() { 94 // try to use the timestamp on the sections file 95 if st, err := os.Stat(dirs.SnapNamesFile); err == nil && st.ModTime().Before(now) { 96 // add the delay with the delta so we spread the load a bit 97 r.nextCatalogRefresh = st.ModTime().Add(catalogRefreshDelayWithDelta) 98 } else { 99 // first time scheduling, add the delta 100 delay = catalogRefreshDelayWithDelta 101 } 102 } 103 104 theStore := Store(r.state, nil) 105 needsRefresh := r.nextCatalogRefresh.IsZero() || r.nextCatalogRefresh.Before(now) 106 107 if !needsRefresh { 108 return nil 109 } 110 111 next := now.Add(delay) 112 // catalog refresh does not carry on trying on error 113 r.nextCatalogRefresh = next 114 115 logger.Debugf("Catalog refresh starting now; next scheduled for %s.", next) 116 117 err = refreshCatalogs(r.state, theStore) 118 switch err { 119 case nil: 120 logger.Debugf("Catalog refresh succeeded.") 121 case store.ErrTooManyRequests: 122 logger.Debugf("Catalog refresh postponed.") 123 err = nil 124 case errSkipCatalogRefreshWhenTesting: 125 logger.Debugf("Catalog refresh skipped when testing is enabled") 126 err = nil 127 default: 128 logger.Debugf("Catalog refresh failed: %v.", err) 129 } 130 return err 131 } 132 133 var newCmdDB = advisor.Create 134 135 var errSkipCatalogRefreshWhenTesting = errors.New("skipping when testing is enabled") 136 137 func refreshCatalogs(st *state.State, theStore StoreService) error { 138 if snapdenv.Testing() && !osutil.GetenvBool("SNAPD_CATALOG_REFRESH") { 139 // with snapd testing enabled, SNAPD_CATALOG_REFRESH is gating 140 // the catalog refresh 141 return errSkipCatalogRefreshWhenTesting 142 } 143 144 st.Unlock() 145 defer st.Lock() 146 147 perfTimings := timings.New(map[string]string{"ensure": "refresh-catalogs"}) 148 149 if err := os.MkdirAll(dirs.SnapCacheDir, 0755); err != nil { 150 return fmt.Errorf("cannot create directory %q: %v", dirs.SnapCacheDir, err) 151 } 152 153 var sections []string 154 var err error 155 timings.Run(perfTimings, "get-sections", "query store for sections", func(tm timings.Measurer) { 156 sections, err = theStore.Sections(auth.EnsureContextTODO(), nil) 157 }) 158 if err != nil { 159 return err 160 } 161 sort.Strings(sections) 162 if err := osutil.AtomicWriteFile(dirs.SnapSectionsFile, []byte(strings.Join(sections, "\n")), 0644, 0); err != nil { 163 return err 164 } 165 166 namesFile, err := osutil.NewAtomicFile(dirs.SnapNamesFile, 0644, 0, osutil.NoChown, osutil.NoChown) 167 if err != nil { 168 return err 169 } 170 defer namesFile.Cancel() 171 172 cmdDB, err := newCmdDB() 173 if err != nil { 174 return err 175 } 176 177 // if all goes well we'll Commit() making this a NOP: 178 defer cmdDB.Rollback() 179 180 timings.Run(perfTimings, "write-catalogs", "query store for catalogs", func(tm timings.Measurer) { 181 err = theStore.WriteCatalogs(auth.EnsureContextTODO(), namesFile, cmdDB) 182 }) 183 if err != nil { 184 return err 185 } 186 187 err1 := namesFile.Commit() 188 err2 := cmdDB.Commit() 189 190 if err2 != nil { 191 return err2 192 } 193 194 st.Lock() 195 perfTimings.Save(st) 196 st.Unlock() 197 198 return err1 199 }