From 816abc2bbc8d24d0935277aa34d67a989a8bd54f Mon Sep 17 00:00:00 2001 From: Evstigneev Denis Date: Sat, 25 Jan 2025 15:57:55 +0300 Subject: [PATCH] add copy metadata from grpc-go (#386) MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Co-authored-by: Василий Толстов Co-authored-by: Vasiliy Tolstov Co-authored-by: vtolstov Reviewed-on: https://git.unistack.org/unistack-org/micro/pulls/386 Co-authored-by: Evstigneev Denis Co-committed-by: Evstigneev Denis --- metadata/context.go | 2 + metadata/metadata.go | 2 + metadata/metadata_grpc.go | 282 ++++++++++++++++++++++++++++++++++++++ 3 files changed, 286 insertions(+) create mode 100644 metadata/metadata_grpc.go diff --git a/metadata/context.go b/metadata/context.go index 475e1b49..471b144a 100644 --- a/metadata/context.go +++ b/metadata/context.go @@ -1,3 +1,5 @@ +//go:build !exclude + // Package metadata is a way of defining message headers package metadata diff --git a/metadata/metadata.go b/metadata/metadata.go index 347c4ec5..f2729e73 100644 --- a/metadata/metadata.go +++ b/metadata/metadata.go @@ -1,3 +1,5 @@ +//go:build !exclude + // Package metadata is a way of defining message headers package metadata diff --git a/metadata/metadata_grpc.go b/metadata/metadata_grpc.go new file mode 100644 index 00000000..f5f2bbf1 --- /dev/null +++ b/metadata/metadata_grpc.go @@ -0,0 +1,282 @@ +//go:build exclude + +// Package metadata TODO need compare with micro metadata +package metadata // import "google.golang.org/grpc/metadata" + +import ( + "context" + "fmt" + "strings" +) + +// MD is a mapping from metadata keys to values. Users should use the following +// two convenience functions New and Pairs to generate MD. +type MD map[string][]string + +type Metadata map[string]string + +// New creates an MD from a given key-value map. +// +// Only the following ASCII characters are allowed in keys: +// - digits: 0-9 +// - uppercase letters: A-Z (normalized to lower) +// - lowercase letters: a-z +// - special characters: -_. +// +// Uppercase letters are automatically converted to lowercase. +// +// Keys beginning with "grpc-" are reserved for grpc-internal use only and may +// result in errors if set in metadata. +func New(m map[string]string) MD { + md := make(MD, len(m)) + for k, val := range m { + key := strings.ToLower(k) + md[key] = append(md[key], val) + } + return md +} + +// Pairs returns an MD formed by the mapping of key, value ... +// Pairs panics if len(kv) is odd. +// +// Only the following ASCII characters are allowed in keys: +// - digits: 0-9 +// - uppercase letters: A-Z (normalized to lower) +// - lowercase letters: a-z +// - special characters: -_. +// +// Uppercase letters are automatically converted to lowercase. +// +// Keys beginning with "grpc-" are reserved for grpc-internal use only and may +// result in errors if set in metadata. +func Pairs(kv ...string) MD { + if len(kv)%2 == 1 { + panic(fmt.Sprintf("metadata: Pairs got the odd number of input pairs for metadata: %d", len(kv))) + } + md := make(MD, len(kv)/2) + for i := 0; i < len(kv); i += 2 { + key := strings.ToLower(kv[i]) + md[key] = append(md[key], kv[i+1]) + } + return md +} + +// Len returns the number of items in md. +func (md MD) Len() int { + return len(md) +} + +// Copy returns a copy of md. +func (md MD) Copy() MD { + out := make(MD, len(md)) + for k, v := range md { + out[k] = copyOf(v) + } + return out +} + +// Get obtains the values for a given key. +// +// k is converted to lowercase before searching in md. +func (md MD) Get(k string) []string { + k = strings.ToLower(k) + return md[k] +} + +// Set sets the value of a given key with a slice of values. +// +// k is converted to lowercase before storing in md. +func (md MD) Set(k string, vals ...string) { + if len(vals) == 0 { + return + } + k = strings.ToLower(k) + md[k] = vals +} + +// Append adds the values to key k, not overwriting what was already stored at +// that key. +// +// k is converted to lowercase before storing in md. +func (md MD) Append(k string, vals ...string) { + if len(vals) == 0 { + return + } + k = strings.ToLower(k) + md[k] = append(md[k], vals...) +} + +// Delete removes the values for a given key k which is converted to lowercase +// before removing it from md. +func (md MD) Delete(k string) { + k = strings.ToLower(k) + delete(md, k) +} + +// Join joins any number of mds into a single MD. +// +// The order of values for each key is determined by the order in which the mds +// containing those values are presented to Join. +func Join(mds ...MD) MD { + out := MD{} + for _, md := range mds { + for k, v := range md { + out[k] = append(out[k], v...) + } + } + return out +} + +type mdIncomingKey struct{} +type mdOutgoingKey struct{} + +// NewIncomingContext creates a new context with incoming md attached. md must +// not be modified after calling this function. +func NewIncomingContext(ctx context.Context, md Metadata) context.Context { + in := make(MD, len(md)) + for k, v := range md { + in[k] = []string{v} + } + + return context.WithValue(ctx, mdIncomingKey{}, in) +} + +// NewOutgoingContext creates a new context with outgoing md attached. If used +// in conjunction with AppendToOutgoingContext, NewOutgoingContext will +// overwrite any previously-appended metadata. md must not be modified after +// calling this function. +func NewOutgoingContext(ctx context.Context, md Metadata) context.Context { + out := make(MD, len(md)) + for k, v := range md { + out[k] = []string{v} + } + + return context.WithValue(ctx, mdOutgoingKey{}, rawMD{md: out}) +} + +// AppendToOutgoingContext returns a new context with the provided kv merged +// with any existing metadata in the context. Please refer to the documentation +// of Pairs for a description of kv. +func AppendToOutgoingContext(ctx context.Context, kv ...string) context.Context { + if len(kv)%2 == 1 { + panic(fmt.Sprintf("metadata: AppendToOutgoingContext got an odd number of input pairs for metadata: %d", len(kv))) + } + md, _ := ctx.Value(mdOutgoingKey{}).(rawMD) + added := make([][]string, len(md.added)+1) + copy(added, md.added) + kvCopy := make([]string, 0, len(kv)) + for i := 0; i < len(kv); i += 2 { + kvCopy = append(kvCopy, strings.ToLower(kv[i]), kv[i+1]) + } + added[len(added)-1] = kvCopy + return context.WithValue(ctx, mdOutgoingKey{}, rawMD{md: md.md, added: added}) +} + +// FromIncomingContext returns the incoming metadata in ctx if it exists. +// +// All keys in the returned MD are lowercase. +func FromIncomingContext(ctx context.Context) (Metadata, bool) { + md, ok := ctx.Value(mdIncomingKey{}).(MD) + if !ok { + return nil, false + } + out := make(Metadata, len(md)) + for k, v := range md { + // We need to manually convert all keys to lower case, because MD is a + // map, and there's no guarantee that the MD attached to the context is + // created using our helper functions. + + if len(v) > 0 { + key := strings.ToLower(k) + out[key] = v[0] + } + + } + return out, true +} + +// ValueFromIncomingContext returns the metadata value corresponding to the metadata +// key from the incoming metadata if it exists. Keys are matched in a case insensitive +// manner. +func ValueFromIncomingContext(ctx context.Context, key string) []string { + md, ok := ctx.Value(mdIncomingKey{}).(MD) + if !ok { + return nil + } + + if v, ok := md[key]; ok { + return copyOf(v) + } + for k, v := range md { + // Case insensitive comparison: MD is a map, and there's no guarantee + // that the MD attached to the context is created using our helper + // functions. + if strings.EqualFold(k, key) { + return copyOf(v) + } + } + return nil +} + +func copyOf(v []string) []string { + vals := make([]string, len(v)) + copy(vals, v) + return vals +} + +// fromOutgoingContextRaw returns the un-merged, intermediary contents of rawMD. +// +// Remember to perform strings.ToLower on the keys, for both the returned MD (MD +// is a map, there's no guarantee it's created using our helper functions) and +// the extra kv pairs (AppendToOutgoingContext doesn't turn them into +// lowercase). +func fromOutgoingContextRaw(ctx context.Context) (MD, [][]string, bool) { + raw, ok := ctx.Value(mdOutgoingKey{}).(rawMD) + if !ok { + return nil, nil, false + } + + return raw.md, raw.added, true +} + +// FromOutgoingContext returns the outgoing metadata in ctx if it exists. +// +// All keys in the returned MD are lowercase. +func FromOutgoingContext(ctx context.Context) (Metadata, bool) { + raw, ok := ctx.Value(mdOutgoingKey{}).(rawMD) + if !ok { + return nil, false + } + + mdSize := len(raw.md) + for i := range raw.added { + mdSize += len(raw.added[i]) / 2 + } + + out := make(Metadata, mdSize) + for k, v := range raw.md { + // We need to manually convert all keys to lower case, because MD is a + // map, and there's no guarantee that the MD attached to the context is + // created using our helper functions. + if len(v) > 0 { + key := strings.ToLower(k) + out[key] = v[0] + } + } + for _, added := range raw.added { + if len(added)%2 == 1 { + panic(fmt.Sprintf("metadata: FromOutgoingContext got an odd number of input pairs for metadata: %d", len(added))) + } + + for i := 0; i < len(added); i += 2 { + key := strings.ToLower(added[i]) + out[key] = added[i+1] + } + } + return out, ok +} + +type rawMD struct { + md MD + added [][]string +}