[MM-20979] Add first implementation of the Bleve search engine (#14562)

* [MM-20979] Add first implementation of the Bleve search engine

* Fix i18n

* Migrate searchengine utils tests

* Fix linter

* Don't add allTermsQ if both termQueries and notTermQueries are empty

* Fix test that should work if user is system admin

* Modify naming according to review comments

* Abstract getIndexDir function

* Extracting bleve engine name as a constant

* Merge both Indexer interfaces into one

* Add worker stopped message

* Allow worker to be started/stopped with config change

* Use constants for index names

* Modify test order

* Fix linter

* Trying to unlock the CI

vendor/github.com/RoaringBitmap/roaring/serialization_generic.go

@@ -0,0 +1,133 @@
+// +build !amd64,!386 appengine
+
+package roaring
+
+import (
+	"encoding/binary"
+	"errors"
+	"io"
+)
+
+func (b *arrayContainer) writeTo(stream io.Writer) (int, error) {
+	buf := make([]byte, 2*len(b.content))
+	for i, v := range b.content {
+		base := i * 2
+		buf[base] = byte(v)
+		buf[base+1] = byte(v >> 8)
+	}
+	return stream.Write(buf)
+}
+
+func (b *arrayContainer) readFrom(stream io.Reader) (int, error) {
+	err := binary.Read(stream, binary.LittleEndian, b.content)
+	if err != nil {
+		return 0, err
+	}
+	return 2 * len(b.content), nil
+}
+
+func (b *bitmapContainer) writeTo(stream io.Writer) (int, error) {
+	if b.cardinality <= arrayDefaultMaxSize {
+		return 0, errors.New("refusing to write bitmap container with cardinality of array container")
+	}
+
+	// Write set
+	buf := make([]byte, 8*len(b.bitmap))
+	for i, v := range b.bitmap {
+		base := i * 8
+		buf[base] = byte(v)
+		buf[base+1] = byte(v >> 8)
+		buf[base+2] = byte(v >> 16)
+		buf[base+3] = byte(v >> 24)
+		buf[base+4] = byte(v >> 32)
+		buf[base+5] = byte(v >> 40)
+		buf[base+6] = byte(v >> 48)
+		buf[base+7] = byte(v >> 56)
+	}
+	return stream.Write(buf)
+}
+
+func (b *bitmapContainer) readFrom(stream io.Reader) (int, error) {
+	err := binary.Read(stream, binary.LittleEndian, b.bitmap)
+	if err != nil {
+		return 0, err
+	}
+	b.computeCardinality()
+	return 8 * len(b.bitmap), nil
+}
+
+func (bc *bitmapContainer) asLittleEndianByteSlice() []byte {
+	by := make([]byte, len(bc.bitmap)*8)
+	for i := range bc.bitmap {
+		binary.LittleEndian.PutUint64(by[i*8:], bc.bitmap[i])
+	}
+	return by
+}
+
+func uint64SliceAsByteSlice(slice []uint64) []byte {
+	by := make([]byte, len(slice)*8)
+
+	for i, v := range slice {
+		binary.LittleEndian.PutUint64(by[i*8:], v)
+	}
+
+	return by
+}
+
+func uint16SliceAsByteSlice(slice []uint16) []byte {
+	by := make([]byte, len(slice)*2)
+
+	for i, v := range slice {
+		binary.LittleEndian.PutUint16(by[i*2:], v)
+	}
+
+	return by
+}
+
+func byteSliceAsUint16Slice(slice []byte) []uint16 {
+	if len(slice)%2 != 0 {
+		panic("Slice size should be divisible by 2")
+	}
+
+	b := make([]uint16, len(slice)/2)
+
+	for i := range b {
+		b[i] = binary.LittleEndian.Uint16(slice[2*i:])
+	}
+
+	return b
+}
+
+func byteSliceAsUint64Slice(slice []byte) []uint64 {
+	if len(slice)%8 != 0 {
+		panic("Slice size should be divisible by 8")
+	}
+
+	b := make([]uint64, len(slice)/8)
+
+	for i := range b {
+		b[i] = binary.LittleEndian.Uint64(slice[8*i:])
+	}
+
+	return b
+}
+
+// Converts a byte slice to a interval16 slice.
+// The function assumes that the slice byte buffer is run container data
+// encoded according to Roaring Format Spec
+func byteSliceAsInterval16Slice(byteSlice []byte) []interval16 {
+	if len(byteSlice)%4 != 0 {
+		panic("Slice size should be divisible by 4")
+	}
+
+	intervalSlice := make([]interval16, len(byteSlice)/4)
+
+	for i := range intervalSlice {
+		intervalSlice[i] = interval16{
+			start:  binary.LittleEndian.Uint16(byteSlice[i*4:]),
+			length: binary.LittleEndian.Uint16(byteSlice[i*4+2:]),
+		}
+	}
+
+	return intervalSlice
+}