1. 背景
不论是开发Java还是你正在学习的Golang，都会遇到依赖管理问题。Java有牛逼轰轰的Maven和Gradle。 Golang亦有godep、govendor、glide、gvt、gopack等等，本文主要给大家介绍gilde。 glide是Golang的包管理工具，是为了解决Golang依赖问题的。 为什么需要glide？ 原因很简单，Go 语言原生包管理的缺陷。罗列一下golang的 get 子命令管理依赖有很多大缺陷：
* 能拉取源码的平台很有限，绝大多数依赖的是 github.com
* 不能区分版本，以至于令开发者以最后一项包名作为版本划分
* 依赖 列表/关系 无法持久化到本地，需要找出所有依赖包然后一个个 go get
* 只能依赖本地全局仓库（GOPATH/GOROOT），无法将库放置于局部仓库（$PROJECT_HOME/vendor）
2. Error问题
项目中使用到了golang.org/x/crypto/ssh包，而由于国内网络原因，无法直接下载，需要提前从github.com/golang/crypto下载然后放到指定位置
* 项目中glide依赖初始化
[lisea@lisea test]$ glide init[INFO] Generating a YAML configuration file and guessing the dependencies[INFO] Attempting to import from other package managers (use --skip-import to skip)[INFO] Scanning code to look for dependencies[INFO] --> Found reference to github.com/pkg/sftp[INFO] --> Found reference to golang.org/x/crypto/ssh[INFO] Writing configuration file (glide.yaml)[INFO] Would you like Glide to help you find ways to improve your glide.yaml configuration?[INFO] If you want to revisit this step you can use the config-wizard command at any time.[INFO] Yes (Y) or No (N)?Y[INFO] Loading mirrors from mirrors.yaml file[INFO] Looking for dependencies to make suggestions on[INFO] --> Scanning for dependencies not using version ranges[INFO] --> Scanning for dependencies using commit ids[INFO] Gathering information on each dependency[INFO] --> This may take a moment. Especially on a codebase with many dependencies[INFO] --> Gathering release information for dependencies[INFO] --> Looking for dependency imports where versions are commit idsY[INFO] Here are some suggestions...[INFO] The package github.com/pkg/sftp appears to have Semantic Version releases (http://semver.org). [INFO] The latest release is 1.2.0. You are currently not using a release. Would you like[INFO] to use this release? Yes (Y) or No (N)[INFO] Would you like to remember the previous decision and apply it to future[INFO] dependencies? Yes (Y) or No (N)Y[INFO] Updating github.com/pkg/sftp to use the release 1.2.0 instead of no release[INFO] The package github.com/pkg/sftp appears to use semantic versions (http://semver.org).[INFO] Would you like to track the latest minor or patch releases (major.minor.patch)?[INFO] Tracking minor version releases would use '>= 1.2.0, < 2.0.0' ('^1.2.0'). Tracking patch version[INFO] releases would use '>= 1.2.0, < 1.3.0' ('~1.2.0'). For more information on Glide versions[INFO] and ranges see https://glide.sh/docs/versions[INFO] Minor (M), Patch (P), or Skip Ranges (S)?P[INFO] Would you like to remember the previous decision and apply it to future[INFO] dependencies? Yes (Y) or No (N)Y[INFO] Updating github.com/pkg/sftp to use the range ~1.2.0 instead of commit id 1.2.0[INFO] Configuration changes have been made. Would you like to write these[INFO] changes to your configuration file? Yes (Y) or No (N)Y[INFO] Writing updates to configuration file (glide.yaml)[INFO] You can now edit the glide.yaml file.:[INFO] --> For more information on versions and ranges see https://glide.sh/docs/versions/[INFO] --> For details on additional metadata see https://glide.sh/docs/glide.yaml/* 初始化后生成的依赖如下:(glide.yaml)
[lisea@lisea test]$ cat glide.yaml package: testimport:- package: github.com/pkg/sftp version: ~1.2.0- package: golang.org/x/crypto/ssh
* glide安装依赖[ERROR报错]
[lisea@lisea test]$ glide install[INFO] Loading mirrors from mirrors.yaml file[INFO] Lock file (glide.lock) does not exist. Performing update.[INFO] Loading mirrors from mirrors.yaml file[INFO] Downloading dependencies. Please wait...[INFO] --> Fetching golang.org/x/crypto/ssh[INFO] --> Fetching updates for github.com/pkg/sftp[WARN] Unable to checkout golang.org/x/crypto/ssh[ERROR] Update failed for golang.org/x/crypto/ssh: Cannot detect VCS[ERROR] Failed to do initial checkout of config: Cannot detect VCS
3. ERROR解决
经通过度娘查询一圈发现，十个结果九个一样内容（在此鄙视抓内容的站点和纯copy的博主三秒种），最后在glide开源点github上的issue上找到解决方式
* 修改glide生成的glide.yaml文件
package: testimport:- package: github.com/pkg/sftp version: ~1.2.0- package: golang.org/x/crypto/ssh
修改为：
package: testimport:- package: github.com/pkg/sftp version: ~1.2.0- package: golang.org/x/crypto subpackages: - ssh
* 重新更新下载依赖
[lisea@lisea test]$ glide up[INFO] Loading mirrors from mirrors.yaml file[INFO] Downloading dependencies. Please wait...[INFO] --> Fetching updates for golang.org/x/crypto[INFO] --> Fetching updates for github.com/pkg/sftp[INFO] --> Detected semantic version. Setting version for github.com/pkg/sftp to 1.2.0[INFO] Resolving imports[INFO] --> Fetching updates for github.com/kr/fs[INFO] --> Fetching updates for github.com/pkg/errors[INFO] Downloading dependencies. Please wait...[INFO] Setting references for remaining imports[INFO] Exporting resolved dependencies...[INFO] --> Exporting github.com/pkg/errors[INFO] --> Exporting github.com/pkg/sftp[INFO] --> Exporting golang.org/x/crypto[INFO] --> Exporting github.com/kr/fs[INFO] Replacing existing vendor dependencies[INFO] Project relies on 4 dependencies.
successfully 成功解决
4. 总结
以需求驱动技术，技术本身没有优略之分，只有业务之分。