refactor(sender, receiver, relay): changed use of .env file to a config file

added support for a config file. under linux this will be under
XDG_HOME/.config/caesar with name caesar.toml

Cargo.lock

@@ -413,7 +413,9 @@ dependencies = [
  "axum-client-ip",
  "caesar-core",
  "clap 4.5.4",
- "dotenv",
+ "confy",
+ "dotenvy",
+ "lazy_static",
  "serde",
  "serde_json",
  "tokio",
@@ -543,11 +545,26 @@ dependencies = [
  "atty",
  "bitflags 1.3.2",
  "strsim 0.8.0",
- "textwrap",
+ "textwrap 0.11.0",
  "unicode-width",
  "vec_map",
 ]
 
+[[package]]
+name = "clap"
+version = "3.2.25"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ea181bf566f71cb9a5d17a59e1871af638180a18fb0035c92ae62b705207123"
+dependencies = [
+ "atty",
+ "bitflags 1.3.2",
+ "clap_lex 0.2.4",
+ "indexmap 1.9.3",
+ "strsim 0.10.0",
+ "termcolor",
+ "textwrap 0.16.1",
+]
+
 [[package]]
 name = "clap"
 version = "4.5.4"
@@ -566,7 +583,7 @@ checksum = "ae129e2e766ae0ec03484e609954119f123cc1fe650337e155d03b022f24f7b4"
 dependencies = [
  "anstream",
  "anstyle",
- "clap_lex",
+ "clap_lex 0.7.0",
  "strsim 0.11.1",
 ]
 
@@ -582,6 +599,15 @@ dependencies = [
  "syn 2.0.60",
 ]
 
+[[package]]
+name = "clap_lex"
+version = "0.2.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2850f2f5a82cbf437dd5af4d49848fbdfc27c157c3d010345776f952765261c5"
+dependencies = [
+ "os_str_bytes",
+]
+
 [[package]]
 name = "clap_lex"
 version = "0.7.0"
@@ -616,6 +642,18 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "confy"
+version = "0.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "45b1f4c00870f07dc34adcac82bb6a72cc5aabca8536ba1797e01df51d2ce9a0"
+dependencies = [
+ "directories",
+ "serde",
+ "thiserror",
+ "toml",
+]
+
 [[package]]
 name = "const-oid"
 version = "0.9.6"
@@ -780,6 +818,27 @@ dependencies = [
  "subtle",
 ]
 
+[[package]]
+name = "directories"
+version = "5.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9a49173b84e034382284f27f1af4dcbbd231ffa358c0fe316541a7337f376a35"
+dependencies = [
+ "dirs-sys",
+]
+
+[[package]]
+name = "dirs-sys"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "520f05a5cbd335fae5a99ff7a6ab8627577660ee5cfd6a94a6a929b52ff0321c"
+dependencies = [
+ "libc",
+ "option-ext",
+ "redox_users",
+ "windows-sys 0.48.0",
+]
+
 [[package]]
 name = "dotenv"
 version = "0.15.0"
@@ -789,6 +848,15 @@ dependencies = [
  "clap 2.34.0",
 ]
 
+[[package]]
+name = "dotenvy"
+version = "0.15.7"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1aaf95b3e5c8f23aa320147307562d361db0ae0d51242340f558153b4eb2439b"
+dependencies = [
+ "clap 3.2.25",
+]
+
 [[package]]
 name = "ecdsa"
 version = "0.16.9"
@@ -1460,6 +1528,16 @@ version = "0.2.154"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ae743338b92ff9146ce83992f766a31066a91a8c84a45e0e9f21e7cf6de6d346"
 
+[[package]]
+name = "libredox"
+version = "0.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c0ff37bd590ca25063e35af745c343cb7a0271906fb7b37e4813e8f79f00268d"
+dependencies = [
+ "bitflags 2.5.0",
+ "libc",
+]
+
 [[package]]
 name = "linux-raw-sys"
 version = "0.4.13"
@@ -1758,6 +1836,12 @@ dependencies = [
  "thiserror",
 ]
 
+[[package]]
+name = "option-ext"
+version = "0.2.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "04744f49eae99ab78e0d5c0b603ab218f515ea8cfe5a456d7629ad883a3b6e7d"
+
 [[package]]
 name = "ordered-float"
 version = "4.2.0"
@@ -1767,6 +1851,12 @@ dependencies = [
  "num-traits",
 ]
 
+[[package]]
+name = "os_str_bytes"
+version = "6.6.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e2355d85b9a3786f481747ced0e0ff2ba35213a1f9bd406ed906554d7af805a1"
+
 [[package]]
 name = "overload"
 version = "0.1.1"
@@ -2071,6 +2161,17 @@ dependencies = [
  "bitflags 2.5.0",
 ]
 
+[[package]]
+name = "redox_users"
+version = "0.4.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bd283d9651eeda4b2a83a43c1c91b266c40fd76ecd39a50a8c630ae69dc72891"
+dependencies = [
+ "getrandom",
+ "libredox",
+ "thiserror",
+]
+
 [[package]]
 name = "regex"
 version = "1.10.4"
@@ -2367,6 +2468,15 @@ dependencies = [
  "serde",
 ]
 
+[[package]]
+name = "serde_spanned"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "eb3622f419d1296904700073ea6cc23ad690adbd66f13ea683df73298736f0c1"
+dependencies = [
+ "serde",
+]
+
 [[package]]
 name = "serde_urlencoded"
 version = "0.7.1"
@@ -2604,6 +2714,12 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
+[[package]]
+name = "strsim"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
+
 [[package]]
 name = "strsim"
 version = "0.11.1"
@@ -2724,6 +2840,15 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "termcolor"
+version = "1.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "06794f8f6c5c898b3275aebefa6b8a1cb24cd2c6c79397ab15774837a0bc5755"
+dependencies = [
+ "winapi-util",
+]
+
 [[package]]
 name = "textwrap"
 version = "0.11.0"
@@ -2733,6 +2858,12 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "textwrap"
+version = "0.16.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "23d434d3f8967a09480fb04132ebe0a3e088c173e6d0ee7897abbdf4eab0f8b9"
+
 [[package]]
 name = "thiserror"
 version = "1.0.59"
@@ -2879,6 +3010,40 @@ dependencies = [
  "tokio",
 ]
 
+[[package]]
+name = "toml"
+version = "0.8.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e9dd1545e8208b4a5af1aa9bbd0b4cf7e9ea08fabc5d0a5c67fcaafa17433aa3"
+dependencies = [
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "toml_edit",
+]
+
+[[package]]
+name = "toml_datetime"
+version = "0.6.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3550f4e9685620ac18a50ed434eb3aec30db8ba93b0287467bca5826ea25baf1"
+dependencies = [
+ "serde",
+]
+
+[[package]]
+name = "toml_edit"
+version = "0.22.12"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d3328d4f68a705b2a4498da1d580585d39a6510f98318a2cec3018a7ec61ddef"
+dependencies = [
+ "indexmap 2.2.6",
+ "serde",
+ "serde_spanned",
+ "toml_datetime",
+ "winnow",
+]
+
 [[package]]
 name = "tonic"
 version = "0.10.2"
@@ -3331,6 +3496,15 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
 
+[[package]]
+name = "winapi-util"
+version = "0.1.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4d4cc384e1e73b93bafa6fb4f1df8c41695c8a91cf9c4c64358067d15a7b6c6b"
+dependencies = [
+ "windows-sys 0.52.0",
+]
+
 [[package]]
 name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
@@ -3485,6 +3659,15 @@ version = "0.52.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "bec47e5bfd1bff0eeaf6d8b485cc1074891a197ab4225d504cb7a1ab88b02bf0"
 
+[[package]]
+name = "winnow"
+version = "0.6.8"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c3c52e9c97a68071b23e836c9380edae937f17b9c4667bd021973efc689f618d"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "winreg"
 version = "0.52.0"