moved hashing to shellscript to check for posts

removes dependency on sha2 crate and allows users
to choose their own hashing algorithm easily.

now copies clinte.json to $HOME/.clinte.json once
the posts are viewed. a shellscript can be used to
compare the hash of the global clinte.json to the
hash of the copy. an example script is supplied.

on `make install` the example script is installed
to /etc/profile.d/, where it will be run for users
on login.

6 files changed, 29 insertions, 131 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 3f5bec1..82b2b10 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -74,35 +74,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "block-buffer"
-version = "0.8.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "block-padding 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
- "byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)",
- "generic-array 0.14.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "block-padding"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
-name = "byte-tools"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
-name = "byteorder"
-version = "1.3.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "cfg-if"
 version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -141,7 +112,6 @@ dependencies = [
  "log 0.4.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 1.0.110 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_json 1.0.53 (registry+https://github.com/rust-lang/crates.io-index)",
- "sha2 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
  "simplelog 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "users 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)",
 ]
@@ -161,14 +131,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "digest"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "generic-array 0.14.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "dirs"
 version = "2.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -209,11 +171,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "fake-simd"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "fd-lock"
 version = "1.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -224,15 +181,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "generic-array"
-version = "0.14.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "typenum 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "version_check 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "getrandom"
 version = "0.1.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -301,11 +249,6 @@ version = "0.19.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
-name = "opaque-debug"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "proc-macro2"
 version = "1.0.17"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -386,17 +329,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "sha2"
-version = "0.9.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-dependencies = [
- "block-buffer 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "digest 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)",
- "fake-simd 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
- "opaque-debug 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)",
-]
-
-[[package]]
 name = "simplelog"
 version = "0.7.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -460,11 +392,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "typenum"
-version = "1.12.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "unicode-width"
 version = "0.1.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -483,11 +410,6 @@ dependencies = [
 ]
 
 [[package]]
-name = "version_check"
-version = "0.9.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-
-[[package]]
 name = "wasi"
 version = "0.9.0+wasi-snapshot-preview1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -522,23 +444,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum base64 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b41b7ea54a0c9d92199de89e20e58d49f02f8e699814ef3fdf266f6f748d15c7"
 "checksum bitflags 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "cf1de2fe8c75bc145a2f577add951f8134889b4795d47466a54a5c846d691693"
 "checksum blake2b_simd 0.5.10 (registry+https://github.com/rust-lang/crates.io-index)" = "d8fb2d74254a3a0b5cac33ac9f8ed0e44aa50378d9dbb2e5d83bd21ed1dc2c8a"
-"checksum block-buffer 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "dbcf92448676f82bb7a334c58bbce8b0d43580fb5362a9d608b18879d12a3d31"
-"checksum block-padding 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "fa79dedbb091f449f1f39e53edf88d5dbe95f895dae6135a8d7b881fb5af73f5"
-"checksum byte-tools 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "e3b5ca7a04898ad4bcd41c90c5285445ff5b791899bb1b0abdd2a2aa791211d7"
-"checksum byteorder 1.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "08c48aae112d48ed9f069b33538ea9e3e90aa263cfa3d1c24309612b1f7472de"
 "checksum cfg-if 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "4785bdd1c96b2a846b2bd7cc02e86b6b3dbf14e7e53446c4f54c92a361040822"
 "checksum chrono 0.4.10 (registry+https://github.com/rust-lang/crates.io-index)" = "31850b4a4d6bae316f7a09e691c944c28299298837edc0a03f755618c23cbc01"
 "checksum clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
 "checksum constant_time_eq 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "245097e9a4535ee1e3e3931fcfcd55a796a44c643e8596ff6566d68f09b87bbc"
 "checksum crossbeam-utils 0.6.6 (registry+https://github.com/rust-lang/crates.io-index)" = "04973fa96e96579258a5091af6003abde64af786b860f18622b82e026cca60e6"
-"checksum digest 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d3dd60d1080a57a05ab032377049e0591415d2b31afd7028356dbf3cc6dcb066"
 "checksum dirs 2.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "13aea89a5c93364a98e9b37b2fa237effbb694d5cfe01c5b70941f7eb087d5e3"
 "checksum dirs-sys 0.3.4 (registry+https://github.com/rust-lang/crates.io-index)" = "afa0b23de8fd801745c471deffa6e12d248f962c9fd4b4c33787b055599bde7b"
 "checksum failure 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "d32e9bd16cc02eae7db7ef620b392808b89f6a5e16bb3497d159c6b92a0f4f86"
 "checksum failure_derive 0.1.8 (registry+https://github.com/rust-lang/crates.io-index)" = "aa4da3c766cd7a0db8242e326e9e4e081edd567072893ed320008189715366a4"
-"checksum fake-simd 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
 "checksum fd-lock 1.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a15bec795244d49f5ee3024bdc6c3883fb035f7f6601d4a4821c3d5d60784454"
-"checksum generic-array 0.14.2 (registry+https://github.com/rust-lang/crates.io-index)" = "ac746a5f3bbfdadd6106868134545e684693d54d9d44f6e9588a7d54af0bf980"
 "checksum getrandom 0.1.14 (registry+https://github.com/rust-lang/crates.io-index)" = "7abc8dd8451921606d809ba32e95b6111925cd2906060d2dcc29c070220503eb"
 "checksum gimli 0.21.0 (registry+https://github.com/rust-lang/crates.io-index)" = "bcc8e0c9bce37868955864dbecd2b1ab2bdf967e6f28066d65aaac620444b65c"
 "checksum hermit-abi 0.1.6 (registry+https://github.com/rust-lang/crates.io-index)" = "eff2656d88f158ce120947499e971d743c05dbcbed62e5bd2f38f1698bbc3772"
@@ -549,7 +464,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum num-integer 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "3f6ea62e9d81a77cd3ee9a2a5b9b609447857f3d358704331e4ef39eb247fcba"
 "checksum num-traits 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "c62be47e61d1842b9170f0fdeec8eba98e60e90e5446449a0545e5152acd7096"
 "checksum object 0.19.0 (registry+https://github.com/rust-lang/crates.io-index)" = "9cbca9424c482ee628fa549d9c812e2cd22f1180b9222c9200fdfa6eb31aecb2"
-"checksum opaque-debug 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "2839e79665f131bdb5782e51f2c6c9599c133c6098982a54c794358bf432529c"
 "checksum proc-macro2 1.0.17 (registry+https://github.com/rust-lang/crates.io-index)" = "1502d12e458c49a4c9cbff560d0fe0060c252bc29799ed94ca2ed4bb665a0101"
 "checksum quote 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "54a21852a652ad6f610c9510194f398ff6f8692e334fd1145fed931f7fbe44ea"
 "checksum redox_syscall 0.1.56 (registry+https://github.com/rust-lang/crates.io-index)" = "2439c63f3f6139d1b57529d16bc3b8bb855230c8efcc5d3a896c8bea7c3b1e84"
@@ -560,7 +474,6 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum serde 1.0.110 (registry+https://github.com/rust-lang/crates.io-index)" = "99e7b308464d16b56eba9964e4972a3eee817760ab60d88c3f86e1fecb08204c"
 "checksum serde_derive 1.0.110 (registry+https://github.com/rust-lang/crates.io-index)" = "818fbf6bfa9a42d3bfcaca148547aa00c7b915bec71d1757aa2d44ca68771984"
 "checksum serde_json 1.0.53 (registry+https://github.com/rust-lang/crates.io-index)" = "993948e75b189211a9b31a7528f950c6adc21f9720b6438ff80a7fa2f864cea2"
-"checksum sha2 0.9.0 (registry+https://github.com/rust-lang/crates.io-index)" = "72377440080fd008550fe9b441e854e43318db116f90181eef92e9ae9aedab48"
 "checksum simplelog 0.7.4 (registry+https://github.com/rust-lang/crates.io-index)" = "05a3e303ace6adb0a60a9e9e2fbc6a33e1749d1e43587e2125f7efa9c5e107c5"
 "checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 "checksum syn 1.0.27 (registry+https://github.com/rust-lang/crates.io-index)" = "ef781e621ee763a2a40721a8861ec519cb76966aee03bb5d00adb6a31dc1c1de"
@@ -568,11 +481,9 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 "checksum term 0.6.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c0863a3345e70f61d613eab32ee046ccd1bcc5f9105fe402c61fcd0c13eeb8b5"
 "checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
 "checksum time 0.1.42 (registry+https://github.com/rust-lang/crates.io-index)" = "db8dcfca086c1143c9270ac42a2bbd8a7ee477b78ac8e45b19abfb0cbede4b6f"
-"checksum typenum 1.12.0 (registry+https://github.com/rust-lang/crates.io-index)" = "373c8a200f9e67a0c95e62a4f52fbf80c23b4381c05a17845531982fa99e6b33"
 "checksum unicode-width 0.1.7 (registry+https://github.com/rust-lang/crates.io-index)" = "caaa9d531767d1ff2150b9332433f32a24622147e5ebb1f26409d5da67afd479"
 "checksum unicode-xid 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "826e7639553986605ec5979c7dd957c7895e93eabed50ab2ffa7f6128a75097c"
 "checksum users 0.9.1 (registry+https://github.com/rust-lang/crates.io-index)" = "c72f4267aea0c3ec6d07eaabea6ead7c5ddacfafc5e22bcf8d186706851fb4cf"
-"checksum version_check 0.9.2 (registry+https://github.com/rust-lang/crates.io-index)" = "b5a972e5669d67ba988ce3dc826706fb0a8b01471c088cb0b6110b805cc36aed"
 "checksum wasi 0.9.0+wasi-snapshot-preview1 (registry+https://github.com/rust-lang/crates.io-index)" = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
 "checksum winapi 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)" = "8093091eeb260906a183e6ae1abdba2ef5ef2257a21801128899c3fc699229c6"
 "checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
diff --git a/Cargo.toml b/Cargo.toml
index 7f59527..6942652 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -22,7 +22,6 @@ lazy_static = "^1.4"
 log = "^0.4"
 serde = { version = "^1.0", features = ["derive"] }
 serde_json = "^1.0"
-sha2 = "^0.9"
 simplelog = "^0.7"
 users = "^0.9"
 
diff --git a/Makefile b/Makefile
index 7d43699..366d375 100644
--- a/Makefile
+++ b/Makefile
@@ -37,6 +37,7 @@ install:
 	install -m755 target/release/clinte $(BINDIR)
 
 	@if [ -f "$(DBDIR)/clinte.json" ]; then printf "\n%s\n" "clinte.json exists. Skipping ..."; else install -m666 clinte.json "$(DBDIR)"; fi
+	@if [ -e /etc/profile.d ]; then printf "%s\n" "Installing check_new_clinte_posts.sh to /etc/profile.d" && install -m644 check_new_clinte_posts.sh /etc/profile.d/; fi
 
 	@printf "\n%s\n" "...Done!"
 
diff --git a/check_new_clinte_posts.sh b/check_new_clinte_posts.sh
new file mode 100755
index 0000000..1d2dfbe
--- /dev/null
+++ b/check_new_clinte_posts.sh
@@ -0,0 +1,12 @@
+#!/bin/sh
+
+LOCAL_FILE="$HOME/.clinte.json"
+LOCAL_HASH=$(sha256sum "$LOCAL_FILE" | cut -d' ' -f1)
+
+DBFILE="/usr/local/clinte/clinte.json"
+DBFILE_HASH=$(sha256sum "$DBFILE" | cut -d' ' -f1)
+
+if [ "$LOCAL_HASH" != "$DBFILE_HASH" ]
+then
+    printf "%s\n" "New posts on clinte!"
+fi
\ No newline at end of file
diff --git a/src/db.rs b/src/db.rs
index eeaa27a..20ad5a1 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -1,6 +1,5 @@
 use fd_lock::FdLock;
 use serde::{Deserialize, Serialize};
-use sha2::{Sha256, Digest};
 
 use std::fs;
 use std::fs::File;
@@ -59,27 +58,6 @@ impl Posts {
         out
     }
 
-    // Hash the contents of clinte.json and store it in your
-    // home directory. Useful for determining if there are
-    // new posts.
-    pub fn hash(&self) -> error::Result<()> {
-        let body = error::helper(serde_json::to_string_pretty(&self), "Couldn't reserialize json to record hash");
-        let mut hasher = Sha256::new();
-        hasher.update(body);
-        let hash = format!("{:x}", hasher.finalize());
-    
-        #[cfg(test)]
-        let homedir = std::env::var("PWD")?;
-
-        #[cfg(not(test))]
-        let homedir = std::env::var("HOME")?;
-        
-        let writepath = format!("{}/.clinte.sha256", homedir);
-        fs::write(writepath, &hash)?;
-
-        Ok(())
-    }
-
     pub fn replace(&mut self, n: usize, post: Post) {
         self.posts[n] = post;
     }
@@ -168,22 +146,4 @@ mod tests {
         all.delete(1);
         all.write();
     }
-
-    #[test]
-    fn check_hash() {
-        let strposts = fs::read_to_string(PATH).unwrap();
-        let mut hasher = Sha256::new();
-        hasher.update(strposts);
-        let rhs = format!("{:x}", hasher.finalize());
-
-        let all = Posts::get_all(PATH);
-        all.hash().unwrap();
-
-        let pwd = std::env::var("PWD").unwrap();
-        let hashpath = format!("{}/.clinte.sha256", pwd);
-        let lhs = fs::read_to_string(hashpath.clone()).unwrap();
-        fs::remove_file(hashpath).unwrap();
-
-        assert_eq!(lhs, rhs);
-    }
 }
diff --git a/src/posts.rs b/src/posts.rs
index 0de3d52..1dfd167 100644
--- a/src/posts.rs
+++ b/src/posts.rs
@@ -1,5 +1,8 @@
 use std::io;
 
+#[cfg(not(test))]
+use std::{env, fs};
+
 use crate::conf;
 use crate::db;
 use crate::error;
@@ -83,7 +86,6 @@ pub fn display() -> error::Result<()> {
         .unwrap_or_else(|_| 80);
 
     let all = db::Posts::get_all(db::PATH);
-    all.hash()?;
 
     let mut postvec = Vec::new();
     all.posts().iter().enumerate().for_each(|(id, post)| {
@@ -117,6 +119,19 @@ pub fn display() -> error::Result<()> {
         }
     }
 
+    // copy the json file to the user's home directory
+    // so it can be compared to the global file to check
+    // for new posts.
+    // previously, I'd hashed it, but I feel like it's
+    // better to leave the hashing to UNIX utilities
+    // than to add a heavy-ish dependency.
+    #[cfg(not(test))]
+    {
+        let homedir = env::var("HOME")?;
+        let localdest = format!("{}/.clinte.json", homedir);
+        fs::copy(db::PATH, localdest)?;
+    }
+
     Ok(())
 }