Remove armhf/armv7 support from faasd

See notes in: #364

Signed-off-by: Alex Ellis (OpenFaaS Ltd) <alexellis2@gmail.com>

vendor/github.com/Microsoft/hcsshim/internal/log/hook.go

@@ -1,23 +1,57 @@
 package log
 
 import (
+	"bytes"
+	"reflect"
+	"time"
+
 	"github.com/Microsoft/hcsshim/internal/logfields"
 	"github.com/sirupsen/logrus"
 	"go.opencensus.io/trace"
 )
 
-// Hook serves to intercept and format `logrus.Entry`s before they are passed
-// to the ETW hook.
+const nullString = "null"
+
+// Hook intercepts and formats a [logrus.Entry] before it logged.
 //
-// The containerd shim discards the (formatted) logrus output, and outputs only via ETW.
-// The Linux GCS outputs logrus entries over stdout, which is consumed by the shim and
-// then re-output via the ETW hook.
-type Hook struct{}
+// The shim either outputs the logs through an ETW hook, discarding the (formatted) output
+// or logs output to a pipe for logging binaries to consume.
+// The Linux GCS outputs logrus entries over stdout, which is then consumed and re-output
+// by the shim.
+type Hook struct {
+	// EncodeAsJSON formats structs, maps, arrays, slices, and [bytes.Buffer] as JSON.
+	// Variables of [bytes.Buffer] will be converted to []byte.
+	//
+	// Default is false.
+	EncodeAsJSON bool
+
+	// FormatTime specifies the format for [time.Time] variables.
+	// An empty string disables formatting.
+	// When disabled, the fall back will the JSON encoding, if enabled.
+	//
+	// Default is [TimeFormat].
+	TimeFormat string
+
+	// Duration format converts a [time.Duration] fields to an appropriate encoding.
+	// nil disables formatting.
+	// When disabled, the fall back will the JSON encoding, if enabled.
+	//
+	// Default is [DurationFormatString], which appends a duration unit after the value.
+	DurationFormat DurationFormat
+
+	// AddSpanContext adds [logfields.TraceID] and [logfields.SpanID] fields to
+	// the entry from the span context stored in [logrus.Entry.Context], if it exists.
+	AddSpanContext bool
+}
 
 var _ logrus.Hook = &Hook{}
 
 func NewHook() *Hook {
-	return &Hook{}
+	return &Hook{
+		TimeFormat:     TimeFormat,
+		DurationFormat: DurationFormatString,
+		AddSpanContext: true,
+	}
 }
 
 func (h *Hook) Levels() []logrus.Level {
@@ -25,14 +59,108 @@ func (h *Hook) Levels() []logrus.Level {
 }
 
 func (h *Hook) Fire(e *logrus.Entry) (err error) {
+	// JSON encode, if necessary, then add span information
+	h.encode(e)
 	h.addSpanContext(e)
 
 	return nil
 }
 
+// encode loops through all the fields in the [logrus.Entry] and encodes them according to
+// the settings in [Hook].
+// If [Hook.TimeFormat] is non-empty, it will be passed to [time.Time.Format] for
+// fields of type [time.Time].
+//
+// If [Hook.EncodeAsJSON] is true, then fields that are not numeric, boolean, strings, or
+// errors will be encoded via a [json.Marshal] (with HTML escaping disabled).
+// Chanel- and function-typed fields, as well as unsafe pointers are left alone and not encoded.
+//
+// If [Hook.TimeFormat] and [Hook.DurationFormat] are empty and [Hook.EncodeAsJSON] is false,
+// then this is a no-op.
+func (h *Hook) encode(e *logrus.Entry) {
+	d := e.Data
+
+	formatTime := h.TimeFormat != ""
+	formatDuration := h.DurationFormat != nil
+	if !(h.EncodeAsJSON || formatTime || formatDuration) {
+		return
+	}
+
+	for k, v := range d {
+		// encode types with dedicated formatting options first
+
+		if vv, ok := v.(time.Time); formatTime && ok {
+			d[k] = vv.Format(h.TimeFormat)
+			continue
+		}
+
+		if vv, ok := v.(time.Duration); formatDuration && ok {
+			d[k] = h.DurationFormat(vv)
+			continue
+		}
+
+		// general case JSON encoding
+
+		if !h.EncodeAsJSON {
+			continue
+		}
+
+		switch vv := v.(type) {
+		// built in types
+		// "json" marshals errors as "{}", so leave alone here
+		case bool, string, error, uintptr,
+			int8, int16, int32, int64, int,
+			uint8, uint32, uint64, uint,
+			float32, float64:
+			continue
+
+		// Rather than setting d[k] = vv.String(), JSON encode []byte value, since it
+		// may be a binary payload and not representable as a string.
+		// `case bytes.Buffer,*bytes.Buffer:` resolves `vv` to `interface{}`,
+		// so cannot use `vv.Bytes`.
+		// Could move to below the `reflect.Indirect()` call below, but
+		// that would require additional typematching and dereferencing.
+		// Easier to keep these duplicate branches here.
+		case bytes.Buffer:
+			v = vv.Bytes()
+		case *bytes.Buffer:
+			v = vv.Bytes()
+		}
+
+		// dereference pointer or interface variables
+		rv := reflect.Indirect(reflect.ValueOf(v))
+		// check if `v` is a null pointer
+		if !rv.IsValid() {
+			d[k] = nullString
+			continue
+		}
+
+		switch rv.Kind() {
+		case reflect.Map, reflect.Struct, reflect.Array, reflect.Slice:
+		default:
+			// Bool, [U]?Int*, Float*, Complex*, Uintptr, String: encoded as normal
+			// Chan, Func: not supported by json
+			// Interface, Pointer: dereferenced above
+			// UnsafePointer: not supported by json, not safe to de-reference; leave alone
+			continue
+		}
+
+		b, err := encode(v)
+		if err != nil {
+			// Errors are written to stderr (ie, to `panic.log`) and stops the remaining
+			// hooks (ie, exporting to ETW) from firing. So add encoding errors to
+			// the entry data to be written out, but keep on processing.
+			d[k+"-"+logrus.ErrorKey] = err.Error()
+			// keep the original `v` as the value,
+			continue
+		}
+		d[k] = string(b)
+	}
+}
+
 func (h *Hook) addSpanContext(e *logrus.Entry) {
 	ctx := e.Context
-	if ctx == nil {
+	if !h.AddSpanContext || ctx == nil {
 		return
 	}
 	span := trace.FromContext(ctx)