Merge branch 'caching'

3 files changed, 336 insertions, 14 deletions

diff --git a/Cargo.lock b/Cargo.lock
index 033896f..3081fff 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -1,3 +1,5 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
 [[package]]
 name = "MacTypes-sys"
 version = "2.1.0"
@@ -28,6 +30,18 @@ dependencies = [
 ]
 
 [[package]]
+name = "assert_fs"
+version = "0.11.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "globwalk 0.5.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "predicates 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "predicates-core 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "predicates-tree 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "tempfile 3.0.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "autocfg"
 version = "0.1.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -68,6 +82,14 @@ version = "1.0.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "bstr"
+version = "0.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "build_const"
 version = "0.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -166,6 +188,15 @@ dependencies = [
 ]
 
 [[package]]
+name = "crossbeam-channel"
+version = "0.3.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "crossbeam-utils 0.6.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "smallvec 0.6.9 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "crossbeam-deque"
 version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -205,6 +236,20 @@ dependencies = [
 ]
 
 [[package]]
+name = "difference"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "directories"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "libc 0.2.51 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "docopt"
 version = "1.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -280,6 +325,14 @@ dependencies = [
 ]
 
 [[package]]
+name = "float-cmp"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "num-traits 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "fnv"
 version = "1.0.6"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -331,6 +384,27 @@ dependencies = [
 ]
 
 [[package]]
+name = "globset"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "aho-corasick 0.7.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "bstr 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "fnv 1.0.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "globwalk"
+version = "0.5.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "ignore 0.4.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "walkdir 2.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "h2"
 version = "0.1.18"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -421,6 +495,23 @@ dependencies = [
 ]
 
 [[package]]
+name = "ignore"
+version = "0.4.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "crossbeam-channel 0.3.8 (registry+https://github.com/rust-lang/crates.io-index)",
+ "globset 0.4.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "lazy_static 1.3.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "log 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "memchr 2.2.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+ "same-file 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
+ "thread_local 0.3.6 (registry+https://github.com/rust-lang/crates.io-index)",
+ "walkdir 2.2.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "winapi-util 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "indexmap"
 version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -651,6 +742,11 @@ dependencies = [
 ]
 
 [[package]]
+name = "normalize-line-endings"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "num"
 version = "0.1.42"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -845,6 +941,32 @@ version = "0.3.14"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "predicates"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "difference 2.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "float-cmp 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
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+ "predicates-core 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "regex 1.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
+name = "predicates-core"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
+name = "predicates-tree"
+version = "1.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "predicates-core 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)",
+ "treeline 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
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@@ -1103,6 +1225,8 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 name = "ruuvitag-upload"
 version = "0.2.0"
 dependencies = [
+ "assert_fs 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "directories 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)",
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@@ -1119,6 +1243,14 @@ version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "same-file"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi-util 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
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@@ -1414,6 +1546,11 @@ dependencies = [
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 [[package]]
+name = "treeline"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
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 version = "0.2.2"
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@@ -1507,6 +1644,16 @@ version = "1.0.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "walkdir"
+version = "2.2.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "same-file 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
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+ "winapi-util 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
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+
+[[package]]
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@@ -1541,6 +1688,14 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 
 [[package]]
+name = "winapi-util"
+version = "0.1.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
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+
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 "checksum pkg-config 0.3.14 (registry+https://github.com/rust-lang/crates.io-index)" = "676e8eb2b1b4c9043511a9b7bea0915320d7e502b0a079fb03f9635a5252b18c"
+"checksum predicates 1.0.1 (registry+https://github.com/rust-lang/crates.io-index)" = "53e09015b0d3f5a0ec2d4428f7559bb7b3fff341b4e159fedd1d57fac8b939ff"
+"checksum predicates-core 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "06075c3a3e92559ff8929e7a280684489ea27fe44805174c3ebd9328dcb37178"
+"checksum predicates-tree 1.0.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8e63c4859013b38a76eca2414c64911fba30def9e3202ac461a2d22831220124"
 "checksum proc-macro2 0.4.27 (registry+https://github.com/rust-lang/crates.io-index)" = "4d317f9caece796be1980837fd5cb3dfec5613ebdb04ad0956deea83ce168915"
 "checksum publicsuffix 1.5.2 (registry+https://github.com/rust-lang/crates.io-index)" = "5afecba86dcf1e4fd610246f89899d1924fe12e1e89f555eb7c7f710f3c5ad1d"
 "checksum quote 0.6.12 (registry+https://github.com/rust-lang/crates.io-index)" = "faf4799c5d274f3868a4aae320a0a182cbd2baee377b378f080e16a23e9d80db"
@@ -1680,6 +1848,7 @@ dependencies = [
 "checksum rustc_version 0.2.3 (registry+https://github.com/rust-lang/crates.io-index)" = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 "checksum ruuvi-sensor-protocol 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b38a30b73b0026108461048353bdb06db808cb9abf878915afa8f97b7ec1e0ed"
 "checksum ryu 0.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "eb9e9b8cde282a9fe6a42dd4681319bfb63f121b8a8ee9439c6f4107e58a46f7"
+"checksum same-file 1.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "8f20c4be53a8a1ff4c1f1b2bd14570d2f634628709752f0702ecdd2b3f9a5267"
 "checksum schannel 0.1.15 (registry+https://github.com/rust-lang/crates.io-index)" = "f2f6abf258d99c3c1c5c2131d99d064e94b7b3dd5f416483057f308fea253339"
 "checksum scopeguard 0.3.3 (registry+https://github.com/rust-lang/crates.io-index)" = "94258f53601af11e6a49f722422f6e3425c52b06245a5cf9bc09908b174f5e27"
 "checksum security-framework 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "bfab8dda0e7a327c696d893df9ffa19cadc4bd195797997f5223cf5831beaf05"
@@ -1711,6 +1880,7 @@ dependencies = [
 "checksum tokio-threadpool 0.1.13 (registry+https://github.com/rust-lang/crates.io-index)" = "ec5759cf26cf9659555f36c431b515e3d05f66831741c85b4b5d5dfb9cf1323c"
 "checksum tokio-timer 0.2.10 (registry+https://github.com/rust-lang/crates.io-index)" = "2910970404ba6fa78c5539126a9ae2045d62e3713041e447f695f41405a120c6"
 "checksum tokio-trace-core 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "350c9edade9830dc185ae48ba45667a445ab59f6167ef6d0254ec9d2430d9dd3"
+"checksum treeline 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "a7f741b240f1a48843f9b8e0444fb55fb2a4ff67293b50a9179dfd5ea67f8d41"
 "checksum try-lock 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e604eb7b43c06650e854be16a2a03155743d3752dd1c943f6829e26b7a36e382"
 "checksum try_from 0.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "283d3b89e1368717881a9d51dad843cc435380d8109c9e47d38780a324698d8b"
 "checksum ucd-util 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "535c204ee4d8434478593480b8f86ab45ec9aae0e83c568ca81abf0fd0e88f86"
@@ -1725,10 +1895,12 @@ dependencies = [
 "checksum vcpkg 0.2.6 (registry+https://github.com/rust-lang/crates.io-index)" = "def296d3eb3b12371b2c7d0e83bfe1403e4db2d7a0bba324a12b21c4ee13143d"
 "checksum version_check 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "914b1a6776c4c929a602fafd8bc742e06365d4bcbe48c30f9cca5824f70dc9dd"
 "checksum void 1.0.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6a02e4885ed3bc0f2de90ea6dd45ebcbb66dacffe03547fadbb0eeae2770887d"
+"checksum walkdir 2.2.7 (registry+https://github.com/rust-lang/crates.io-index)" = "9d9d7ed3431229a144296213105a390676cc49c9b6a72bd19f3176c98e129fa1"
 "checksum want 0.0.6 (registry+https://github.com/rust-lang/crates.io-index)" = "797464475f30ddb8830cc529aaaae648d581f99e2036a928877dfde027ddf6b3"
 "checksum winapi 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "167dc9d6949a9b857f3451275e911c3f44255842c1f7a76f33c55103a909087a"
 "checksum winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "f10e386af2b13e47c89e7236a7a14a086791a2b88ebad6df9bf42040195cf770"
 "checksum winapi-build 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "2d315eee3b34aca4797b2da6b13ed88266e6d612562a0c46390af8299fc699bc"
 "checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
+"checksum winapi-util 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7168bab6e1daee33b4557efd0e95d5ca70a03706d39fa5f3fe7a236f584b03c9"
 "checksum winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
 "checksum ws2_32-sys 0.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "d59cefebd0c892fa2dd6de581e937301d8552cb44489cdff035c6187cb63fa5e"
diff --git a/Cargo.toml b/Cargo.toml
index 4d03bf4..aa7ffbf 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -20,6 +20,10 @@ serde = "1.0"
 serde_json = "1.0"
 failure = "0.1"
 reqwest = "0.9.14"
+directories = "1.0"
+
+[dev-dependencies]
+assert_fs = "0.11"
 
 [profile.release]
 # opt-level = 'z'
diff --git a/src/main.rs b/src/main.rs
index dabb04b..c2b94e7 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,4 +1,7 @@
 use std::collections::HashMap;
+use std::fs;
+use std::io::{self, BufReader, Write};
+use std::path::Path;
 use std::process;
 use std::sync::{mpsc::channel, Arc};
 use std::time::{SystemTime, UNIX_EPOCH};
@@ -18,7 +21,9 @@ use docopt;
 
 use reqwest;
 
-#[derive(Serialize)]
+use directories::ProjectDirs;
+
+#[derive(Serialize, Deserialize)]
 struct Measurement {
     address: String,
     // Unix timestamp.
@@ -73,6 +78,15 @@ structure
 where ALIAS will either be the address of the sensor, or
 an alias that you can define.
 
+If uploading measurements fails, the measurements are
+cached. The cached measurements are uploaded the next time
+ruuvitag-upload is called. Cached measurements are uploaded
+first, from oldest to newest. If uploading cached measurements
+fails, the current measurements are again cached for next time.
+This way, you won't lose any measurements. When a cached
+measurement is succesfully uploaded, the cache entry will be
+removed.
+
 USAGE:
 
     ruuvitag-upload [--url=URL] <sensor>...
@@ -144,6 +158,123 @@ fn run() -> Result<(), Error> {
         .map(|(address, alias)| (address.to_string(), alias.to_string()))
         .collect();
 
+    let measurements = collect_measurements(sensors)?;
+
+    if let Some(url) = args.flag_url {
+        let result = upload_cached_measurements(&url);
+
+        // If uploading cached measurements failed, we try to cache the latest measurements.
+        if result.is_err() {
+            eprintln!("error: {}", result.unwrap_err());
+            cache_measurements(measurements)?;
+            return Ok(());
+        }
+
+        let client = reqwest::Client::new();
+
+        let result = match client.post(&url).json(&measurements).send() {
+            Ok(response) => match response.error_for_status() {
+                Ok(response) => Ok(response),
+                Err(error) => Err(error),
+            },
+            Err(error) => Err(error),
+        };
+
+        // If uploading the latest measurements failed, we try to cache them for later uploading.
+        if result.is_err() {
+            eprintln!("error: {}", result.unwrap_err());
+            cache_measurements(measurements)?;
+        }
+    } else {
+        println!("{}", serde_json::to_string(&measurements).unwrap());
+    }
+
+    Ok(())
+}
+
+fn find_cached_measurements(cache_dir: &Path) -> Result<Vec<std::path::PathBuf>, Error> {
+    let mut result = Vec::new();
+
+    // It's OK if we don't find cached data. Other errors are not good.
+    if let Err(error) = fs::metadata(cache_dir) {
+        if error.kind() == io::ErrorKind::NotFound {
+            return Ok(result);
+        }
+        return Err(error.into());
+    }
+
+    for entry in fs::read_dir(cache_dir)? {
+        let entry = entry?;
+        let file_type = entry.file_type()?;
+        if file_type.is_file() {
+            let path = entry.path();
+            if let Some(ext) = path.extension() {
+                if ext == "json" {
+                    result.push(path);
+                }
+            }
+        }
+    }
+
+    result.sort();
+
+    Ok(result)
+}
+
+fn upload_cached_measurements(url: &str) -> Result<(), Error> {
+    let paths = find_cached_measurements(&get_cache_dir()?)?;
+
+    let client = reqwest::Client::new();
+
+    for path in paths {
+        let file = fs::File::open(&path)?;
+        let reader = BufReader::new(file);
+        let measurements: HashMap<String, Measurement> = serde_json::from_reader(reader)?;
+        client
+            .post(url)
+            .json(&measurements)
+            .send()?
+            .error_for_status()?;
+        fs::remove_file(&path)?;
+    }
+
+    Ok(())
+}
+
+fn get_cache_dir() -> Result<std::path::PathBuf, Error> {
+    match ProjectDirs::from("dev", "otimperi", "ruuvitag-upload") {
+        None => Err(failure::format_err!("failed to get cache dir location")),
+        Some(dir) => Ok(dir.data_dir().to_path_buf()),
+    }
+}
+
+fn cache_measurements(measurements: HashMap<String, Measurement>) -> Result<(), Error> {
+    let mut path = get_cache_dir()?;
+
+    path.push(format!(
+        "{}.json",
+        SystemTime::now()
+            .duration_since(UNIX_EPOCH)
+            .unwrap()
+            .as_secs()
+    ));
+
+    eprintln!("caching measurements to {}", path.display());
+
+    std::fs::create_dir_all(path.parent().unwrap())?;
+
+    let mut file = std::fs::File::create(path)?;
+
+    let json = serde_json::to_string(&measurements)?;
+
+    file.write_all(&json.into_bytes())?;
+
+    Ok(())
+}
+
+fn collect_measurements(
+    sensors: HashMap<String, String>,
+) -> Result<HashMap<String, Measurement>, Error> {
     let manager = rumble::bluez::manager::Manager::new()?;
 
     let mut adapter = manager.adapters()?.into_iter().nth(0).unwrap();
@@ -181,19 +312,7 @@ fn run() -> Result<(), Error> {
 
     central.stop_scan()?;
 
-    if let Some(url) = args.flag_url {
-        let client = reqwest::Client::new();
-
-        client
-            .post(&url)
-            .json(&measurements)
-            .send()?
-            .error_for_status()?;
-    } else {
-        println!("{}", serde_json::to_string(&measurements).unwrap());
-    }
-
-    Ok(())
+    Ok(measurements)
 }
 
 fn on_event(
@@ -235,3 +354,30 @@ fn from_manufacturer_data(data: &[u8]) -> Result<SensorValues, ParseError> {
         Err(ParseError::EmptyValue)
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+    use assert_fs::prelude::*;
+
+    #[test]
+    fn test_find_cached_measurements() {
+        let test_dir = assert_fs::TempDir::new().unwrap();
+
+        test_dir.child("1236.json").touch().unwrap();
+        test_dir.child("1233.cmd").touch().unwrap();
+        test_dir.child("1234.json").touch().unwrap();
+        test_dir.child("1235.json").touch().unwrap();
+        test_dir.child("1238.md").touch().unwrap();
+        test_dir.child("1237.txt").touch().unwrap();
+
+        let files: Vec<String> = find_cached_measurements(test_dir.path())
+            .unwrap()
+            .iter()
+            .filter_map(|path| path.file_name())
+            .map(|file_name| file_name.to_string_lossy().into_owned())
+            .collect();
+
+        assert_eq!(files, vec!["1234.json", "1235.json", "1236.json"]);
+    }
+}