[nop] Big code reorg and refactor

Preparing for upcoming switch to ByteBuffer implementation.
No behavioural changes intended with this commit.

Author: ptaoussanis

src/taoensso/nippy.clj

@@ -1,8 +1,9 @@
 (ns ^:no-doc taoensso.nippy.compression
-  "Private, implementation detail."
+  "Private compression utils, don't use."
   (:require
    [taoensso.truss  :as truss]
    [taoensso.encore :as enc])
+
   (:import
    [java.nio ByteBuffer]
    [java.io
@@ -216,3 +217,15 @@
   "Different LZ4 modes no longer supported, prefer `lz4-compressor`."
   {:deprecated "v3.4.0-RC1 (2024-02-06)"}
   (LZ4Compressor.))
+
+(defn get-auto-compressor [compressor-id]
+  (case compressor-id
+    nil        nil
+    :snappy    snappy-compressor
+    :lzma2     lzma2-compressor
+    :lz4       lz4-compressor
+    :zstd      zstd-compressor
+    :no-header (truss/ex-info! ":auto not supported on headerless data." {})
+    :else      (truss/ex-info! ":auto not supported for non-standard compressors." {})
+    (do        (truss/ex-info! (str "Unrecognized :auto compressor id: " compressor-id)
+                 {:compressor-id compressor-id}))))

src/taoensso/nippy/compression.clj

@@ -1,6 +1,5 @@
 (ns ^:no-doc taoensso.nippy.crypto
-  "Low-level crypto utils.
-  Private & alpha, very likely to change!"
+  "Private low-level crypto utils, don't use!!"
   (:refer-clojure :exclude [rand-nth])
   (:require
    [taoensso.truss  :as truss]

src/taoensso/nippy/crypto.clj

@@ -1,5 +1,5 @@
 (ns ^:no-doc taoensso.nippy.encryption
-  "Private, implementation detail."
+  "Private encryption utils, don't use."
   (:require
    [taoensso.truss        :as truss]
    [taoensso.encore       :as enc]
@@ -113,6 +113,16 @@
     (do           (fn [ salt-ba pwd] (crypto/take-ba 16 (crypto/sha512-key-ba salt-ba pwd (* Short/MAX_VALUE 5)))))
     (enc/fmemoize (fn [_salt-ba pwd] (crypto/take-ba 16 (crypto/sha512-key-ba nil     pwd (* Short/MAX_VALUE 64)))))))
 
+(defn get-auto-encryptor [encryptor-id]
+  (case encryptor-id
+    nil                nil
+    :aes128-gcm-sha512 aes128-gcm-encryptor
+    :aes128-cbc-sha512 aes128-cbc-encryptor
+    :no-header (truss/ex-info! ":auto not supported on headerless data." {})
+    :else      (truss/ex-info! ":auto not supported for non-standard encryptors." {})
+    (do        (truss/ex-info! (str "Unrecognized :auto encryptor id: " encryptor-id)
+                 {:encryptor-id encryptor-id}))))
+
 ;;;; Default implementation
 
 (comment