Make it usable

Makefile

@@ -5,3 +5,9 @@ develop:
 test:
 	clojure -X:test
 .PHONY: test
+
+release:
+	clojure -T:build uber
+	cat build/stub.sh target/unsplice-mbox.jar > target/unsplice-mbox
+	chmod a+x target/unsplice-mbox
+.PHONY: release

README.md

@@ -7,6 +7,24 @@ Attachments are decoded (typically from base64) and stored in a content-addressa
 unsplice-mbox was primarily tested with a single Gmail takeout containing about 100K emails over a span of 20 years. While this contained many different edge cases, it is unlikely that all situations are being handled. Feel free to open an issue or submit a patch if you encounter some parsing errors.
 
 
+## Download/installation
+
+You can get a [prebuilt release](releases/) (Java JRE required) or build it yourself (requires a JDK and Clojure):
+
+```shell
+make release
+ls target/unsplice-mbox
+```
+
+
+## Usage
+
+```shell
+# will put attachments into output-mbox.d/
+unsplice-mbox input-mbox output-mbox
+```
+
+
 ## Rationale
 
 Making incremental backups of recurring Gmail takeouts is fairly inefficient because the takeout is a single large file and not append-only.

build.clj

@@ -0,0 +1,19 @@
+(ns build
+  (:require [clojure.tools.build.api :as b]))
+
+(def class-dir "target/classes")
+(def basis (b/create-basis {:project "deps.edn"}))
+(def uber-file (format "target/unsplice-mbox.jar"))
+
+(defn clean [_]
+  (b/delete {:path "target"}))
+
+(defn uber [_]
+  (clean nil)
+  (b/compile-clj {:basis basis
+                  :src-dirs ["src"]
+                  :class-dir class-dir})
+  (b/uber {:class-dir class-dir
+           :uber-file uber-file
+           :basis basis
+           :main 'unsplice.core}))

build/stub.sh

@@ -0,0 +1,12 @@
+#!/usr/bin/env sh
+
+SELF=$(which "$0" 2> /dev/null)
+[ $? -gt 0 -a -f "$0" ] && SELF="./$0"
+
+java=java
+if test -n "$JAVA_HOME"; then
+    java="$JAVA_HOME/bin/java"
+fi
+
+exec "$java" -jar $SELF "$@"
+exit 1

src/unsplice/core.clj

@@ -8,7 +8,10 @@
            [java.security MessageDigest DigestOutputStream]
            [jakarta.mail.internet MimeUtility]
            [dev.baecher.io BoundaryInputStream]
-           [org.apache.commons.codec.binary Base64InputStream]))
+           [org.apache.commons.codec.binary Base64InputStream])
+  (:gen-class))
+
+(def version "0.9.0")
 
 (def cr-lf (.getBytes "\r\n" "ASCII"))
 (def dash-dash (.getBytes "--" "ASCII"))
@@ -198,6 +201,7 @@
             (println "finished" mail-number "mails")))))))
 
 (defn -main [& args]
+  (println "unsplice-mbox " version)
   (when-not (= 2 (count args))
     (println "arguments required: INPUT-FILE OUTPUT-FILE")
     (System/exit -1))