backend: web: Begin JSON-RPC client impl

Starting work on the JSON-RPC client in the web server.

The `Context` structure, which is stored in Rocket's managed state and
available to route functions through the `State` request guard, provides
a method to get an RPC client.  Each request that needs to communicate
with the daemon will have its own RPC connection.  This ensures that a
valid connection is always available, even if the daemon has restarted
between web requests.  I had considered storing the connection in the
context, testing it each time it was needed, and reconnecting if the
connection was broken.  This proved very difficult, since the context is
passed to request handlers as an immutable reference.  Mutating its
state would require locking, and I could not make that work easily.
Besides, the overhead of "pinging" the server for every request is
probably greater than just reconnecting every time, so it would have
been a waste.

The *GET /status* operation returns a document that indicates the status
of the daemon and the web server.

backend/Cargo.lock

@@ -2,6 +2,12 @@
 # It is not intended for manual editing.
 version = 3
 
+[[package]]
+name = "adler"
+version = "1.0.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f26201604c87b1e01bd3d98f8d5d9a8fcbb815e8cedb41ffccbeb4bf593a35fe"
+
 [[package]]
 name = "aead"
 version = "0.3.2"
@@ -56,6 +62,15 @@ dependencies = [
  "opaque-debug",
 ]
 
+[[package]]
+name = "aho-corasick"
+version = "0.7.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e37cfd5e7657ada45f742d6e99ca5788580b5c529dc78faf11ece6dc702656f"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "ansi_term"
 version = "0.12.1"
@@ -185,12 +200,27 @@ dependencies = [
  "generic-array",
 ]
 
+[[package]]
+name = "bstr"
+version = "0.2.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ba3569f383e8f1598449f1a423e72e99569137b47740b1da11ef19af3d5c3223"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "bumpalo"
 version = "3.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a4a45a46ab1f2412e53d3a0ade76ffad2025804294569aae387231a0cd6e0899"
 
+[[package]]
+name = "byteorder"
+version = "1.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
+
 [[package]]
 name = "bytes"
 version = "1.1.0"
@@ -209,6 +239,19 @@ version = "1.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "baf1de4339761588bc0619e3cbc0120ee582ebb74b53b4efbf79117bd2da40fd"
 
+[[package]]
+name = "chrono"
+version = "0.4.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "670ad68c9088c2a963aaa298cb369688cf3f9465ce5e2d4ca10e6e0098a1ce73"
+dependencies = [
+ "libc",
+ "num-integer",
+ "num-traits",
+ "time 0.1.43",
+ "winapi",
+]
+
 [[package]]
 name = "cipher"
 version = "0.2.5"
@@ -224,6 +267,12 @@ version = "0.4.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fbdcdcb6d86f71c5e97409ad45898af11cbc995b4ee8112d59095a28d376c935"
 
+[[package]]
+name = "convert_case"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6245d59a3e82a7fc217c5828a6692dbc6dfb63a0c8c90495621f7b9d79704a0e"
+
 [[package]]
 name = "cookie"
 version = "0.15.1"
@@ -233,11 +282,11 @@ dependencies = [
  "aes-gcm",
  "base64",
  "hkdf",
- "percent-encoding",
+ "percent-encoding 2.1.0",
- "rand",
+ "rand 0.8.4",
  "sha2",
  "subtle",
- "time",
+ "time 0.2.27",
  "version_check",
 ]
 
@@ -256,6 +305,15 @@ version = "0.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "dcb25d077389e53838a8158c8e99174c5a9d902dee4904320db714f3c653ffba"
 
+[[package]]
+name = "crc32fast"
+version = "1.3.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "738c290dfaea84fc1ca15ad9c168d083b05a714e1efddd8edaab678dc28d2836"
+dependencies = [
+ "cfg-if",
+]
+
 [[package]]
 name = "crypto-mac"
 version = "0.10.1"
@@ -275,6 +333,19 @@ dependencies = [
  "cipher",
 ]
 
+[[package]]
+name = "derive_more"
+version = "0.99.17"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4fb810d30a7c1953f91334de7244731fc3f3c10d7fe163338a35b9f640960321"
+dependencies = [
+ "convert_case",
+ "proc-macro2",
+ "quote",
+ "rustc_version 0.4.0",
+ "syn",
+]
+
 [[package]]
 name = "devise"
 version = "0.3.1"
@@ -352,12 +423,30 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "flate2"
+version = "1.0.22"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1e6988e897c1c9c485f43b47a529cef42fde0547f9d8d41a7062518f1d8fc53f"
+dependencies = [
+ "cfg-if",
+ "crc32fast",
+ "libc",
+ "miniz_oxide",
+]
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3f9eec918d3f24069decb9af1554cad7c880e2da24a9afd88aca000531ab82c1"
 
+[[package]]
+name = "futures"
+version = "0.1.31"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3a471a38ef8ed83cd6e40aa59c1ffe17db6855c18e3604d9c4ed8c08ebc28678"
+
 [[package]]
 name = "futures"
 version = "0.3.19"
@@ -398,6 +487,7 @@ dependencies = [
  "futures-core",
  "futures-task",
  "futures-util",
+ "num_cpus",
 ]
 
 [[package]]
@@ -435,6 +525,7 @@ version = "0.3.19"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d9b5cf40b47a271f77a8b1bec03ca09044d99d2372c0de244e66430761127164"
 dependencies = [
+ "futures 0.1.31",
  "futures-channel",
  "futures-core",
  "futures-io",
@@ -470,6 +561,17 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "getrandom"
+version = "0.1.16"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8fc3cb4d91f53b50155bdcfd23f6a4c39ae1969c2ae85982b135750cccaf5fce"
+dependencies = [
+ "cfg-if",
+ "libc",
+ "wasi 0.9.0+wasi-snapshot-preview1",
+]
+
 [[package]]
 name = "getrandom"
 version = "0.2.3"
@@ -478,7 +580,7 @@ checksum = "7fcd999463524c52659517fe2cea98493cfe485d10565e7b0fb07dbba7ad2753"
 dependencies = [
  "cfg-if",
  "libc",
- "wasi",
+ "wasi 0.10.2+wasi-snapshot-preview1",
 ]
 
 [[package]]
@@ -497,6 +599,19 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9b919933a397b79c37e33b77bb2aa3dc8eb6e165ad809e58ff75bc7db2e34574"
 
+[[package]]
+name = "globset"
+version = "0.4.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "10463d9ff00a2a068db14231982f5132edebad0d7660cd956a1c30292dbcbfbd"
+dependencies = [
+ "aho-corasick",
+ "bstr",
+ "fnv",
+ "log",
+ "regex",
+]
+
 [[package]]
 name = "h2"
 version = "0.3.10"
@@ -540,6 +655,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "hex"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "7f24254aa9a54b5c858eaee2f5bccdb46aaf0e486a595ed5fd8f86ba55232a70"
+
 [[package]]
 name = "hkdf"
 version = "0.10.0"
@@ -618,6 +739,17 @@ dependencies = [
  "want",
 ]
 
+[[package]]
+name = "idna"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "38f09e0f0b1fb55fdee1f17470ad800da77af5186a1a76c026b679358b7e844e"
+dependencies = [
+ "matches",
+ "unicode-bidi",
+ "unicode-normalization",
+]
+
 [[package]]
 name = "indexmap"
 version = "1.8.0"
@@ -665,6 +797,110 @@ dependencies = [
  "wasm-bindgen",
 ]
 
+[[package]]
+name = "jsonrpc-client-transports"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2b99d4207e2a04fb4581746903c2bb7eb376f88de9c699d0f3e10feeac0cd3a"
+dependencies = [
+ "derive_more",
+ "futures 0.3.19",
+ "jsonrpc-core",
+ "jsonrpc-pubsub",
+ "jsonrpc-server-utils",
+ "log",
+ "parity-tokio-ipc",
+ "serde",
+ "serde_json",
+ "tokio",
+ "url",
+]
+
+[[package]]
+name = "jsonrpc-core"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "14f7f76aef2d054868398427f6c54943cf3d1caa9a7ec7d0c38d69df97a965eb"
+dependencies = [
+ "futures 0.3.19",
+ "futures-executor",
+ "futures-util",
+ "log",
+ "serde",
+ "serde_derive",
+ "serde_json",
+]
+
+[[package]]
+name = "jsonrpc-core-client"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b51da17abecbdab3e3d4f26b01c5ec075e88d3abe3ab3b05dc9aa69392764ec0"
+dependencies = [
+ "futures 0.3.19",
+ "jsonrpc-client-transports",
+]
+
+[[package]]
+name = "jsonrpc-derive"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b939a78fa820cdfcb7ee7484466746a7377760970f6f9c6fe19f9edcc8a38d2"
+dependencies = [
+ "proc-macro-crate",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
+[[package]]
+name = "jsonrpc-ipc-server"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "382bb0206323ca7cda3dcd7e245cea86d37d02457a02a975e3378fb149a48845"
+dependencies = [
+ "futures 0.3.19",
+ "jsonrpc-core",
+ "jsonrpc-server-utils",
+ "log",
+ "parity-tokio-ipc",
+ "parking_lot",
+ "tower-service",
+]
+
+[[package]]
+name = "jsonrpc-pubsub"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "240f87695e6c6f62fb37f05c02c04953cf68d6408b8c1c89de85c7a0125b1011"
+dependencies = [
+ "futures 0.3.19",
+ "jsonrpc-core",
+ "lazy_static",
+ "log",
+ "parking_lot",
+ "rand 0.7.3",
+ "serde",
+]
+
+[[package]]
+name = "jsonrpc-server-utils"
+version = "18.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "fa4fdea130485b572c39a460d50888beb00afb3e35de23ccd7fad8ff19f0e0d4"
+dependencies = [
+ "bytes",
+ "futures 0.3.19",
+ "globset",
+ "jsonrpc-core",
+ "lazy_static",
+ "log",
+ "tokio",
+ "tokio-stream",
+ "tokio-util",
+ "unicase",
+]
+
 [[package]]
 name = "lazy_static"
 version = "1.4.0"
@@ -719,6 +955,12 @@ dependencies = [
  "regex-automata",
 ]
 
+[[package]]
+name = "matches"
+version = "0.1.9"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a3e378b66a060d48947b590737b30a1be76706c8dd7b8ba0f2fe3989c68a853f"
+
 [[package]]
 name = "memchr"
 version = "2.4.1"
@@ -731,6 +973,16 @@ version = "0.3.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2a60c7ce501c71e03a9c9c0d35b861413ae925bd979cc7a4e30d060069aaac8d"
 
+[[package]]
+name = "miniz_oxide"
+version = "0.4.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a92518e98c078586bc6c934028adcca4c92a53d6a958196de835170a01d84e4b"
+dependencies = [
+ "adler",
+ "autocfg",
+]
+
 [[package]]
 name = "mio"
 version = "0.7.14"
@@ -782,6 +1034,25 @@ dependencies = [
  "winapi",
 ]
 
+[[package]]
+name = "num-integer"
+version = "0.1.44"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d2cc698a63b549a70bc047073d2949cce27cd1c7b0a4a862d08a8031bc2801db"
+dependencies = [
+ "autocfg",
+ "num-traits",
+]
+
+[[package]]
+name = "num-traits"
+version = "0.2.14"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a64b1ec5cda2586e284722486d802acf1f7dbdc623e2bfc57e65ca1cd099290"
+dependencies = [
+ "autocfg",
+]
+
 [[package]]
 name = "num_cpus"
 version = "1.13.1"
@@ -804,6 +1075,20 @@ version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "624a8340c38c1b80fd549087862da4ba43e08858af025b236e509b6649fc13d5"
 
+[[package]]
+name = "parity-tokio-ipc"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9981e32fb75e004cc148f5fb70342f393830e0a4aa62e3cc93b50976218d42b6"
+dependencies = [
+ "futures 0.3.19",
+ "libc",
+ "log",
+ "rand 0.7.3",
+ "tokio",
+ "winapi",
+]
+
 [[package]]
 name = "parking_lot"
 version = "0.11.2"
@@ -852,6 +1137,12 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "percent-encoding"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "31010dd2e1ac33d5b46a5b413495239882813e0369f8ed8a5e266f173602f831"
+
 [[package]]
 name = "percent-encoding"
 version = "2.1.0"
@@ -887,6 +1178,15 @@ version = "0.2.16"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "eb9f9e6e233e5c4a35559a617bf40a4ec447db2e84c20b55a6f83167b7e57872"
 
+[[package]]
+name = "proc-macro-crate"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1d6ea3c4595b96363c13943497db34af4460fb474a95c43f4446ad341b8c9785"
+dependencies = [
+ "toml",
+]
+
 [[package]]
 name = "proc-macro-hack"
 version = "0.5.19"
@@ -915,6 +1215,21 @@ dependencies = [
  "yansi",
 ]
 
+[[package]]
+name = "procfs"
+version = "0.12.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0941606b9934e2d98a3677759a971756eb821f75764d0e0d26946d08e74d9104"
+dependencies = [
+ "bitflags",
+ "byteorder",
+ "chrono",
+ "flate2",
+ "hex",
+ "lazy_static",
+ "libc",
+]
+
 [[package]]
 name = "quote"
 version = "1.0.14"
@@ -924,6 +1239,19 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "rand"
+version = "0.7.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a6b1679d49b24bbfe0c803429aa1874472f50d9b363131f0e89fc356b544d03"
+dependencies = [
+ "getrandom 0.1.16",
+ "libc",
+ "rand_chacha 0.2.2",
+ "rand_core 0.5.1",
+ "rand_hc 0.2.0",
+]
+
 [[package]]
 name = "rand"
 version = "0.8.4"
@@ -931,9 +1259,19 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2e7573632e6454cf6b99d7aac4ccca54be06da05aca2ef7423d22d27d4d4bcd8"
 dependencies = [
  "libc",
- "rand_chacha",
+ "rand_chacha 0.3.1",
- "rand_core",
+ "rand_core 0.6.3",
- "rand_hc",
+ "rand_hc 0.3.1",
+]
+
+[[package]]
+name = "rand_chacha"
+version = "0.2.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f4c8ed856279c9737206bf725bf36935d8666ead7aa69b52be55af369d193402"
+dependencies = [
+ "ppv-lite86",
+ "rand_core 0.5.1",
 ]
 
 [[package]]
@@ -943,7 +1281,16 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e6c10a63a0fa32252be49d21e7709d4d4baf8d231c2dbce1eaa8141b9b127d88"
 dependencies = [
  "ppv-lite86",
- "rand_core",
+ "rand_core 0.6.3",
+]
+
+[[package]]
+name = "rand_core"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "90bde5296fc891b0cef12a6d03ddccc162ce7b2aff54160af9338f8d40df6d19"
+dependencies = [
+ "getrandom 0.1.16",
 ]
 
 [[package]]
@@ -952,7 +1299,16 @@ version = "0.6.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d34f1408f55294453790c48b2f1ebbb1c5b4b7563eb1f418bcfcfdbb06ebb4e7"
 dependencies = [
- "getrandom",
+ "getrandom 0.2.3",
+]
+
+[[package]]
+name = "rand_hc"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca3129af7b92a17112d59ad498c6f81eaf463253766b90396d39ea7a39d6613c"
+dependencies = [
+ "rand_core 0.5.1",
 ]
 
 [[package]]
@@ -961,7 +1317,7 @@ version = "0.3.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d51e9f596de227fda2ea6c84607f5558e196eeaf43c986b724ba4fb8fdf497e7"
 dependencies = [
- "rand_core",
+ "rand_core 0.6.3",
 ]
 
 [[package]]
@@ -999,6 +1355,8 @@ version = "1.5.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d07a8629359eb56f1e2fb1652bb04212c072a87ba68546a04065d525673ac461"
 dependencies = [
+ "aho-corasick",
+ "memchr",
  "regex-syntax",
 ]
 
@@ -1055,7 +1413,7 @@ dependencies = [
  "bytes",
  "either",
  "figment",
- "futures",
+ "futures 0.3.19",
  "indexmap",
  "log",
  "memchr",
@@ -1063,7 +1421,7 @@ dependencies = [
  "num_cpus",
  "parking_lot",
  "pin-project-lite",
- "rand",
+ "rand 0.8.4",
  "ref-cast",
  "rocket_codegen",
  "rocket_http",
@@ -1071,7 +1429,7 @@ dependencies = [
  "serde_json",
  "state",
  "tempfile",
- "time",
+ "time 0.2.27",
  "tokio",
  "tokio-stream",
  "tokio-util",
@@ -1112,14 +1470,14 @@ dependencies = [
  "mime",
  "parking_lot",
  "pear",
- "percent-encoding",
+ "percent-encoding 2.1.0",
  "pin-project-lite",
  "ref-cast",
  "serde",
  "smallvec",
  "stable-pattern",
  "state",
- "time",
+ "time 0.2.27",
  "tokio",
  "tokio-rustls",
  "uncased",
@@ -1131,7 +1489,16 @@ version = "0.2.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "138e3e0acb6c9fb258b19b67cb8abd63c00679d2851805ea151465464fe9030a"
 dependencies = [
- "semver",
+ "semver 0.9.0",
+]
+
+[[package]]
+name = "rustc_version"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bfa0f585226d2e68097d4f95d113b15b83a82e819ab25717ec0590d9584ef366"
+dependencies = [
+ "semver 1.0.4",
 ]
 
 [[package]]
@@ -1190,6 +1557,12 @@ dependencies = [
  "semver-parser",
 ]
 
+[[package]]
+name = "semver"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "568a8e6258aa33c13358f81fd834adb854c6f7c9468520910a9b1e8fac068012"
+
 [[package]]
 name = "semver-parser"
 version = "0.7.0"
@@ -1332,7 +1705,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d022496b16281348b52d0e30ae99e01a73d737b2f45d38fed4edf79f9325a1d5"
 dependencies = [
  "discard",
- "rustc_version",
+ "rustc_version 0.2.3",
  "stdweb-derive",
  "stdweb-internal-macros",
  "stdweb-internal-runtime",
@@ -1399,7 +1772,7 @@ checksum = "dac1c663cfc93810f88aed9b8941d48cabf856a1b111c29a40439018d870eb22"
 dependencies = [
  "cfg-if",
  "libc",
- "rand",
+ "rand 0.8.4",
  "redox_syscall",
  "remove_dir_all",
  "winapi",
@@ -1414,6 +1787,16 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "time"
+version = "0.1.43"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ca8a50ef2360fbd1eeb0ecd46795a87a19024eb4b53c5dc916ca1fd95fe62438"
+dependencies = [
+ "libc",
+ "winapi",
+]
+
 [[package]]
 name = "time"
 version = "0.2.27"
@@ -1452,6 +1835,21 @@ dependencies = [
  "syn",
 ]
 
+[[package]]
+name = "tinyvec"
+version = "1.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2c1c1d5a42b6245520c249549ec267180beaffcc0615401ac8e31853d4b6d8d2"
+dependencies = [
+ "tinyvec_macros",
+]
+
+[[package]]
+name = "tinyvec_macros"
+version = "0.1.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cda74da7e1a664f795bb1f8a87ec406fb89a02522cf6e50620d016add6dbbf5c"
+
 [[package]]
 name = "tokio"
 version = "1.15.0"
@@ -1624,6 +2022,30 @@ dependencies = [
  "version_check",
 ]
 
+[[package]]
+name = "unicase"
+version = "2.6.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "50f37be617794602aabbeee0be4f259dc1778fabe05e2d67ee8f79326d5cb4f6"
+dependencies = [
+ "version_check",
+]
+
+[[package]]
+name = "unicode-bidi"
+version = "0.3.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1a01404663e3db436ed2746d9fefef640d868edae3cceb81c3b8d5732fda678f"
+
+[[package]]
+name = "unicode-normalization"
+version = "0.1.19"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d54590932941a9e9266f0832deed84ebe1bf2e4c9e4a3554d393d18f5e854bf9"
+dependencies = [
+ "tinyvec",
+]
+
 [[package]]
 name = "unicode-segmentation"
 version = "1.8.0"
@@ -1652,6 +2074,17 @@ version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "a156c684c91ea7d62626509bce3cb4e1d9ed5c4d978f7b4352658f96a4c26b4a"
 
+[[package]]
+name = "url"
+version = "1.7.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd4e7c0d531266369519a4aa4f399d748bd37043b00bde1e4ff1f60a120b355a"
+dependencies = [
+ "idna",
+ "matches",
+ "percent-encoding 1.0.1",
+]
+
 [[package]]
 name = "version_check"
 version = "0.9.4"
@@ -1668,6 +2101,12 @@ dependencies = [
  "try-lock",
 ]
 
+[[package]]
+name = "wasi"
+version = "0.9.0+wasi-snapshot-preview1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cccddf32554fecc6acb585f82a32a72e28b48f8c4c1883ddfeeeaa96f7d8e519"
+
 [[package]]
 name = "wasi"
 version = "0.10.2+wasi-snapshot-preview1"
@@ -1753,7 +2192,13 @@ name = "weywot"
 version = "0.1.0"
 dependencies = [
  "argh",
+ "chrono",
  "figment",
+ "jsonrpc-core",
+ "jsonrpc-core-client",
+ "jsonrpc-derive",
+ "jsonrpc-ipc-server",
+ "procfs",
  "rocket",
  "serde",
 ]

backend/Cargo.toml

@@ -5,9 +5,21 @@ edition = "2018"
 
 [dependencies]
 argh = "^0.1"
+chrono = "*"
 figment = "^0.10"
+jsonrpc-core = "~18.0"
+jsonrpc-derive = "~18.0"
+jsonrpc-ipc-server = "~18.0"
 serde = "^1.0"
 
+[dependencies.jsonrpc-core-client]
+version = "~18.0"
+features = ["ipc"]
+
+[dependencies.procfs]
+version = "^0.12"
+features = ["chrono"]
+
 [dependencies.rocket]
 version = "^0.5.0-rc.1"
 features = ["json", "secrets", "tls"]

backend/src/daemon/mod.rs

@@ -0,0 +1,31 @@
+mod rpc;
+use crate::rpc::WeywotRpc;
+use argh::FromArgs;
+use jsonrpc_core::IoHandler;
+use jsonrpc_ipc_server::ServerBuilder;
+use std::env;
+
+#[derive(Debug, FromArgs)]
+/// Weywot privileged daemon
+struct Arguments {
+    #[argh(option, short = 's')]
+    /// socket path
+    socket: Option<String>,
+}
+
+pub fn main() {
+    let args: Arguments = argh::from_env();
+    let socket = if let Ok(v) = env::var("WEYWOT_SOCKET") {
+        v
+    } else {
+        if let Some(v) = args.socket {
+            v
+        } else {
+            "weywot.sock".into()
+        }
+    };
+    let mut io = IoHandler::new();
+    io.extend_with(rpc::RpcDaemon.to_delegate());
+    let server = ServerBuilder::new(io).start(&socket).unwrap();
+    server.wait();
+}

backend/src/daemon/rpc.rs

@@ -0,0 +1,27 @@
+use crate::models::status::DaemonStatus;
+use crate::rpc::WeywotRpc;
+use chrono::Local;
+use jsonrpc_core::Result as JsonRpcResult;
+use procfs::process::Process;
+use std::convert::TryInto;
+use std::error::Error;
+use std::process;
+
+pub struct RpcDaemon;
+
+impl WeywotRpc for RpcDaemon {
+    fn status(&self) -> JsonRpcResult<DaemonStatus> {
+        Ok(DaemonStatus {
+            version: env!("CARGO_PKG_VERSION").into(),
+            runtime: proc_runtime().unwrap_or(0),
+        })
+    }
+}
+
+fn proc_runtime() -> Result<i64, Box<dyn Error>> {
+    let pid: i32 = process::id().try_into()?;
+    let proc = Process::new(pid)?;
+    let starttime = proc.stat.starttime()?;
+    let now = Local::now();
+    Ok((now - starttime).num_seconds())
+}

backend/src/main.rs

@@ -1,3 +1,6 @@
+mod daemon;
+mod models;
+mod rpc;
 mod server;
 
 use std::env;
@@ -20,7 +23,7 @@ fn main() {
 
 /// Main entry point for the privileged daemon
 fn daemon_main() {
-    /* start the privileged daemon */
+    daemon::main();
 }
 
 /// Main entry point for the web server

backend/src/models/mod.rs

@@ -0,0 +1 @@
+pub mod status;

backend/src/models/status.rs

@@ -0,0 +1,18 @@
+use serde::{Deserialize, Serialize};
+
+#[derive(Debug, Deserialize, Serialize)]
+pub struct DaemonStatus {
+    pub version: String,
+    pub runtime: i64,
+}
+
+#[derive(Debug, Serialize)]
+pub struct WebServerStatus {
+    pub version: String,
+}
+
+#[derive(Debug, Serialize)]
+pub struct StatusResponse {
+    pub daemon: DaemonStatus,
+    pub web: WebServerStatus,
+}

backend/src/rpc.rs

@@ -0,0 +1,9 @@
+use crate::models::status::DaemonStatus;
+use jsonrpc_core::Result;
+use jsonrpc_derive::rpc;
+
+#[rpc]
+pub trait WeywotRpc {
+    #[rpc(name = "status")]
+    fn status(&self) -> Result<DaemonStatus>;
+}

backend/src/server/config.rs

@@ -4,6 +4,7 @@ use serde::{Deserialize, Serialize};
 pub struct Config {
     pub address: String,
     pub port: u16,
+    pub socket: String
 }
 
 impl Default for Config {
@@ -11,6 +12,7 @@ impl Default for Config {
         Config {
             address: "::".into(),
             port: 8998,
+            socket: "weywot.sock".into(),
         }
     }
 }

backend/src/server/context.rs

@@ -0,0 +1,31 @@
+use crate::rpc::gen_client::Client;
+use crate::server::error::{ApiError, ErrorResponse};
+use jsonrpc_core_client::transports::ipc::connect;
+use rocket::http::Status as HttpStatus;
+use rocket::serde::json::Json;
+use std::path::PathBuf;
+
+pub struct Context {
+    socket_path: PathBuf,
+}
+
+impl Context {
+    pub fn new<P: Into<PathBuf>>(socket: P) -> Self {
+        Self {
+            socket_path: socket.into(),
+        }
+    }
+
+    pub async fn client(&self) -> Result<Client, ApiError> {
+        match connect(&self.socket_path).await {
+            Ok(client) => Ok(client),
+            Err(e) => Err((
+                HttpStatus::ServiceUnavailable,
+                Json(ErrorResponse::new(format!(
+                    "Cannot connect to daemon: {}",
+                    e
+                ))),
+            )),
+        }
+    }
+}

backend/src/server/error.rs

@@ -0,0 +1,18 @@
+use rocket::http::Status as HttpStatus;
+use rocket::serde::json::Json;
+use rocket::serde::Serialize;
+
+#[derive(Serialize)]
+pub struct ErrorResponse {
+    pub error: String,
+}
+
+pub type ApiError = (HttpStatus, Json<ErrorResponse>);
+
+impl ErrorResponse {
+    pub fn new<S: Into<String>>(message: S) -> Self {
+        Self {
+            error: message.into(),
+        }
+    }
+}

backend/src/server/mod.rs

@@ -1,8 +1,11 @@
 mod config;
+mod context;
+mod error;
 mod routes;
 use config::Config;
 
 use argh::FromArgs;
+use context::Context;
 use rocket;
 use rocket::fairing::AdHoc;
 use rocket::figment::providers::{Env, Format, Serialized, Toml};
@@ -24,6 +27,10 @@ struct Arguments {
     /// configuration file
     #[argh(option, short = 'c')]
     config: Option<String>,
+
+    /// weywot daemon socket path
+    #[argh(option, short = 's')]
+    socket: Option<String>,
 }
 
 #[rocket::main]
@@ -42,10 +49,22 @@ pub async fn main() -> Result<(), rocket::Error> {
     if let Some(port) = args.port {
         figment = figment.merge(("port", port));
     }
+    if let Some(socket) = args.socket {
+        figment = figment.merge(("socket", socket));
+    }
+
+    let context = Context::new(
+        figment
+            .find_value("socket")
+            .expect("No daemon socket path configured")
+            .as_str()
+            .expect("Invalid daemon socket path"),
+    );
 
     rocket::custom(figment)
-        .mount("/", rocket::routes![routes::hello::hello])
+        .mount("/", rocket::routes![routes::status::get_status])
         .attach(AdHoc::config::<Config>())
+        .manage(context)
         .ignite()
         .await?
         .launch()

backend/src/server/routes/hello.rs

@@ -1,6 +0,0 @@
-use rocket;
-
-#[rocket::get("/")]
-pub async fn hello() -> &'static str {
-    "Hello, world!"
-}

backend/src/server/routes/mod.rs

@@ -1 +1 @@
-pub mod hello;
+pub mod status;

backend/src/server/routes/status.rs

@@ -0,0 +1,18 @@
+use crate::models::status::{StatusResponse, WebServerStatus};
+use crate::server::context::Context;
+use crate::server::error::ApiError;
+use rocket::serde::json::Json;
+use rocket::State;
+
+#[rocket::get("/status")]
+pub async fn get_status(
+    state: &State<Context>,
+) -> Result<Json<StatusResponse>, ApiError> {
+    let client = state.client().await?;
+    Ok(Json(StatusResponse {
+        daemon: client.status().await.unwrap(),
+        web: WebServerStatus {
+            version: env!("CARGO_PKG_VERSION").into(),
+        },
+    }))
+}