最近尝试在一个项目中引用一个私有crate，这个crate是一个lib，然后存储在私有git仓库中，并且这个git平台不支持rust的crate-index.

• 第一坑，引用git依赖

于是我在我的项目中这样引用外部依赖包

[package]
name = "las"
version = "0.1.1"
authors = ["...."]
edition = "2018"

[dependencies]
elasticsearch = { version = "8.5.0-alpha.1", default-features = false, features = [
    "rustls-tls",
] }
logwatcher = "0.1.1"
json = "*"
reqwest = { version = "0.11.12", default-features = false, features = [
    "blocking",
    "rustls-tls",
] }
toml = "0.8.6"
serde_derive = "1.0.177"
serde = "1.0.177"
serde_json = "1.0.104"
once_cell = "1.18.0"
futures = "0.3"
tokio = { version = "*", features = ["full"] }
uuid = { version = "1.4", features = ["v4", "fast-rng", "macro-diagnostics"] }
chrono = "0.4"
core_affinity = "0.8.0"
geoip = { git = "ssh://git@git.xxxx.com/xxxx/tgeoip.git", branch = "master", package = "geoip" }

nix = "0.26"
libc = "0.2.146"
clap = { version = "4.4.2", features = ["derive"] }
log4rs = { version = "1.2.0" }
log = { version = "0.4.20" }
[build-dependencies]
regex = "1.6.0"

需要注意的是，我git@git.xxxx.com:xxxx/tgeoip.git仓库中是一个workspace，里面有2个子项，一个是可执行bin项目，叫做regen，一个是外部可依赖包，叫做geoip（后续实践表明同一个workspace里面的子项引用就应该这么干，git路径是同一个，使用package指定子项的包名），我这样引入之后，发现死活拉取不了私有git依赖。报错没权限拉取，git鉴权失败

error: failed to get `geoip` as a dependency of package `las v0.1.1 (/data/code/rust/las)`

Caused by:
  failed to load source for dependency `geoip`

Caused by:
  Unable to update ssh://git@git.xxxx.com/xxxx/tgeoip.git?branch=master#e41c5279

Caused by:
  failed to clone into: /root/.cargo/git/db/tgeoip-9094aceea5940357

Caused by:
  failed to authenticate when downloading repository

  * attempted ssh-agent authentication, but no usernames succeeded: `git`

  if the git CLI succeeds then `net.git-fetch-with-cli` may help here
  https://doc.rust-lang.org/cargo/reference/config.html#netgit-fetch-with-cli

Caused by:
  no authentication methods succeeded

各方查询后，都是建议添加这个选项，我开始还没搞清楚加在哪儿，但是发现使用环境变量好使。各方尝试后：

添加到~/.cargo/config文件中，如下

[net]
git-fetch-with-cli = true

然后再次执行cargo build无需环境变量即可。（前提是你本地已经配置好了访问ssh://git@git.xxxx.com/xxxx/tgeoip.git的ssh key）

• 第二坑，外部依赖包要申明为rlib

我在这个bin项目中引用geoip，发现一直报错

failed to resolve: use of undeclared crate or module `geoip`

百思不得其解，最后发现是我依赖包申明类型的问题，我Cargo.toml申明的是

[package]
....

[lib]
name = "geoip"
crate-type = ["staticlib", "cdylib"]

[dependencies]
bincode = "1.3.3"
serde = { version = "1.0.193", features = ["derive"] }

实际lib应该申明rlib类型，才能被正常引用，改为如下，更新依赖，就没报错了

[package]
....

[lib]
name = "geoip"
crate-type = ["staticlib", "cdylib", "rlib"]

[dependencies]
bincode = "1.3.3"
serde = { version = "1.0.193", features = ["derive"] }