--- a/rust/Cargo.lock	Thu Feb 23 23:27:09 2017 +0800
+++ b/rust/Cargo.lock	Tue Feb 28 22:58:47 2017 +0800
@@ -14,6 +14,7 @@
  "rustc-serialize 0.3.22 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde 0.9.7 (registry+https://github.com/rust-lang/crates.io-index)",
  "serde_derive 0.9.7 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde_json 0.9.8 (registry+https://github.com/rust-lang/crates.io-index)",
  "time 0.1.36 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-core 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
  "tokio-curl 0.1.9 (registry+https://github.com/rust-lang/crates.io-index)",
@@ -83,6 +84,11 @@
 ]
 
 [[package]]
+name = "dtoa"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "env_logger"
 version = "0.3.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -124,6 +130,11 @@
 ]
 
 [[package]]
+name = "itoa"
+version = "0.3.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "kernel32-sys"
 version = "0.2.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -217,6 +228,11 @@
 ]
 
 [[package]]
+name = "num-traits"
+version = "0.1.36"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+
+[[package]]
 name = "num_cpus"
 version = "1.2.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -332,6 +348,17 @@
 ]
 
 [[package]]
+name = "serde_json"
+version = "0.9.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+dependencies = [
+ "dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)",
+ "num-traits 0.1.36 (registry+https://github.com/rust-lang/crates.io-index)",
+ "serde 0.9.7 (registry+https://github.com/rust-lang/crates.io-index)",
+]
+
+[[package]]
 name = "slab"
 version = "0.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
@@ -497,11 +524,13 @@
 "checksum curl 0.4.6 (registry+https://github.com/rust-lang/crates.io-index)" = "c90e1240ef340dd4027ade439e5c7c2064dd9dc652682117bd50d1486a3add7b"
 "checksum curl-sys 0.3.10 (registry+https://github.com/rust-lang/crates.io-index)" = "c0d909dc402ae80b6f7b0118c039203436061b9d9a3ca5d2c2546d93e0a61aaa"
 "checksum docopt 0.7.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ab32ea6e284d87987066f21a9e809a73c14720571ef34516f0890b3d355ccfd8"
+"checksum dtoa 0.4.1 (registry+https://github.com/rust-lang/crates.io-index)" = "80c8b71fd71146990a9742fc06dcbbde19161a267e0ad4e572c35162f4578c90"
 "checksum env_logger 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "15abd780e45b3ea4f76b4e9a26ff4843258dd8a3eed2775a0e7368c2e7936c2f"
 "checksum futures 0.1.10 (registry+https://github.com/rust-lang/crates.io-index)" = "c1913eb7083840b1bbcbf9631b7fda55eaf35fe7ead13cca034e8946f9e2bc41"
 "checksum futures-cpupool 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)" = "9e48a3fff6a58fe9df1eed13d2599650416a987386c43a19aec656c3e6a2c229"
 "checksum gcc 0.3.43 (registry+https://github.com/rust-lang/crates.io-index)" = "c07c758b972368e703a562686adb39125707cc1ef3399da8c019fc6c2498a75d"
 "checksum gdi32-sys 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "0912515a8ff24ba900422ecda800b52f4016a56251922d397c576bf92c690518"
+"checksum itoa 0.3.1 (registry+https://github.com/rust-lang/crates.io-index)" = "eb2f404fbc66fd9aac13e998248505e7ecb2ad8e44ab6388684c5fb11c6c251c"
 "checksum kernel32-sys 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "7507624b29483431c0ba2d82aece8ca6cdba9382bff4ddd0f7490560c056098d"
 "checksum lazy_static 0.2.2 (registry+https://github.com/rust-lang/crates.io-index)" = "6abe0ee2e758cd6bc8a2cd56726359007748fbf4128da998b65d0b70f881e19b"
 "checksum lazycell 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ce12306c4739d86ee97c23139f3a34ddf0387bbf181bc7929d287025a8c3ef6b"
@@ -513,6 +542,7 @@
 "checksum mio 0.6.4 (registry+https://github.com/rust-lang/crates.io-index)" = "eecdbdd49a849336e77b453f021c89972a2cfb5b51931a0026ae0ac4602de681"
 "checksum miow 0.2.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3a78d2605eb97302c10cf944b8d96b0a2a890c52957caf92fcd1f24f69049579"
 "checksum net2 0.2.26 (registry+https://github.com/rust-lang/crates.io-index)" = "5edf9cb6be97212423aed9413dd4729d62b370b5e1c571750e882cebbbc1e3e2"
+"checksum num-traits 0.1.36 (registry+https://github.com/rust-lang/crates.io-index)" = "a16a42856a256b39c6d3484f097f6713e14feacd9bfb02290917904fae46c81c"
 "checksum num_cpus 1.2.1 (registry+https://github.com/rust-lang/crates.io-index)" = "a225d1e2717567599c24f88e49f00856c6e825a12125181ee42c4257e3688d39"
 "checksum openssl-probe 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "756d49c8424483a3df3b5d735112b4da22109ced9a8294f1f5cdf80fb3810919"
 "checksum openssl-sys 0.9.7 (registry+https://github.com/rust-lang/crates.io-index)" = "5dd48381e9e8a6dce9c4c402db143b2e243f5f872354532f7a009c289b3998ca"
@@ -529,6 +559,7 @@
 "checksum serde 0.9.7 (registry+https://github.com/rust-lang/crates.io-index)" = "1e0ed773960f90a78567fcfbe935284adf50c5d7cf119aa2cf43bb0b4afa69bb"
 "checksum serde_codegen_internals 0.13.0 (registry+https://github.com/rust-lang/crates.io-index)" = "c3172bf2940b975c0e4f6ab42a511c0a4407d4f46ccef87a9d3615db5c26fa96"
 "checksum serde_derive 0.9.7 (registry+https://github.com/rust-lang/crates.io-index)" = "6af30425c5161deb200aac4803c62b903eb3be7e889c5823d0e16c4ce0ce989c"
+"checksum serde_json 0.9.8 (registry+https://github.com/rust-lang/crates.io-index)" = "6501ac6f8b74f9b1033f7ddf79a08edfa0f58d6f8e3190cb8dc97736afa257a8"
 "checksum slab 0.3.0 (registry+https://github.com/rust-lang/crates.io-index)" = "17b4fcaed89ab08ef143da37bc52adbcc04d4a69014f4c1208d6b51f0c47bc23"
 "checksum strsim 0.6.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b4d15c810519a91cf877e7e36e63fe068815c678181439f2f29e2562147c3694"
 "checksum syn 0.11.4 (registry+https://github.com/rust-lang/crates.io-index)" = "f4f94368aae82bb29656c98443a7026ca931a659e8d19dcdc41d6e273054e820"