diff options
author | Vincent Ambo <tazjin@google.com> | 2019-09-30T13·25+0100 |
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committer | Vincent Ambo <github@tazj.in> | 2019-10-03T12·21+0100 |
commit | 6e2b84f475fb302bf6d8a43c2f7497040ad82cac (patch) | |
tree | 2dda96ac195a258752df9d8c1847837c49a6a21c /tools | |
parent | 6262dec8aacf25ae6004de739353089cd635cea5 (diff) |
feat(server): Add cache for layer builds in GCS & local cache
This cache is going to be used for looking up whether a layer build has taken place already (based on a hash of the layer contents). See the caching section in the updated documentation for details. Relates to #50.
Diffstat (limited to 'tools')
-rw-r--r-- | tools/nixery/server/builder/cache.go | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/tools/nixery/server/builder/cache.go b/tools/nixery/server/builder/cache.go index 52765293f3e4..edb1b711d853 100644 --- a/tools/nixery/server/builder/cache.go +++ b/tools/nixery/server/builder/cache.go @@ -14,7 +14,9 @@ package builder import ( + "bytes" "context" + "encoding/json" "io" "log" "os" @@ -25,14 +27,25 @@ import ( type void struct{} +type Build struct { + SHA256 string `json:"sha256"` + MD5 string `json:"md5"` +} + // LocalCache implements the structure used for local caching of // manifests and layer uploads. type LocalCache struct { + // Manifest cache mmtx sync.RWMutex mcache map[string]string + // Layer (tarball) cache lmtx sync.RWMutex lcache map[string]void + + // Layer (build) cache + bmtx sync.RWMutex + bcache map[string]Build } func NewCache() LocalCache { @@ -80,6 +93,22 @@ func (c *LocalCache) localCacheManifest(key, path string) { c.mmtx.Unlock() } +// Retrieve a cached build from the local cache. +func (c *LocalCache) buildFromLocalCache(key string) (*Build, bool) { + c.bmtx.RLock() + b, ok := c.bcache[key] + c.bmtx.RUnlock() + + return &b, ok +} + +// Add a build result to the local cache. +func (c *LocalCache) localCacheBuild(key string, b Build) { + c.bmtx.Lock() + c.bcache[key] = b + c.bmtx.Unlock() +} + // Retrieve a manifest from the cache(s). First the local cache is // checked, then the GCS-bucket cache. func manifestFromCache(ctx *context.Context, cache *LocalCache, bucket *storage.BucketHandle, key string) (string, bool) { @@ -118,6 +147,7 @@ func manifestFromCache(ctx *context.Context, cache *LocalCache, bucket *storage. return path, true } +// Add a manifest to the bucket & local caches func cacheManifest(ctx *context.Context, cache *LocalCache, bucket *storage.BucketHandle, key, path string) { cache.localCacheManifest(key, path) @@ -144,3 +174,59 @@ func cacheManifest(ctx *context.Context, cache *LocalCache, bucket *storage.Buck log.Printf("Cached manifest sha1:%s (%v bytes written)\n", key, size) } + +// Retrieve a build from the cache, first checking the local cache +// followed by the bucket cache. +func buildFromCache(ctx *context.Context, cache *LocalCache, bucket *storage.BucketHandle, key string) (*Build, bool) { + build, cached := cache.buildFromLocalCache(key) + if cached { + return build, true + } + + obj := bucket.Object("builds/" + key) + _, err := obj.Attrs(*ctx) + if err != nil { + return nil, false + } + + r, err := obj.NewReader(*ctx) + if err != nil { + log.Printf("Failed to retrieve build '%s' from cache: %s\n", key, err) + return nil, false + } + defer r.Close() + + jb := bytes.NewBuffer([]byte{}) + _, err = io.Copy(jb, r) + if err != nil { + log.Printf("Failed to read build '%s' from cache: %s\n", key, err) + return nil, false + } + + var b Build + err = json.Unmarshal(jb.Bytes(), &build) + if err != nil { + log.Printf("Failed to unmarshal build '%s' from cache: %s\n", key, err) + return nil, false + } + + return &b, true +} + +func cacheBuild(ctx context.Context, cache *LocalCache, bucket *storage.BucketHandle, key string, build Build) { + cache.localCacheBuild(key, build) + + obj := bucket.Object("builds/" + key) + + j, _ := json.Marshal(&build) + + w := obj.NewWriter(ctx) + + size, err := io.Copy(w, bytes.NewReader(j)) + if err != nil { + log.Printf("failed to cache build '%s': %s\n", key, err) + return + } + + log.Printf("cached build '%s' (%v bytes written)\n", key, size) +} |