1. 背景
不論是開發Java還是你正在學習的Golang，都會遇到依賴管理問題。Java有牛逼轟轟的Maven和Gradle。 Golang亦有godep、govendor、glide、gvt、gopack等等，本文主要給大家介紹gilde。 glide是Golang的包管理工具，是爲了解決Golang依賴問題的。 爲什麼需要glide？ 原因很簡單，Go 語言原生包管理的缺陷。羅列一下golang的 get 子命令管理依賴有很多大缺陷：
* 能拉取源碼的平臺很有限，絕大多數依賴的是 github.com
* 不能區分版本，以至於令開發者以最後一項包名作爲版本劃分
* 依賴 列表/關係 無法持久化到本地，需要找出所有依賴包然後一個個 go get
* 只能依賴本地全局倉庫（GOPATH/GOROOT），無法將庫放置於局部倉庫（$PROJECT_HOME/vendor）
2. Error問題
項目中使用到了golang.org/x/crypto/ssh包，而由於國內網絡原因，無法直接下載，需要提前從github.com/golang/crypto下載然後放到指定位置
* 項目中glide依賴初始化
[lisea@lisea test]$ 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 ids
Y
[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/* 初始化後生成的依賴如下:(glide.yaml)
[lisea@lisea test]$ cat glide.yaml package: test import: - package: github.com/pkg/sftp version: ~1.2.0 - package: golang.org/x/crypto/ssh
* glide安裝依賴[ERROR報錯]
[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解決
經通過度娘查詢一圈發現，十個結果九個一樣內容（在此鄙視抓內容的站點和純copy的博主三秒種），最後在glide開源點github上的issue上找到解決方式
* 修改glide生成的glide.yaml文件
package: test import: - package: github.com/pkg/sftp version: ~1.2.0 - package: golang.org/x/crypto/ssh
修改爲：
package: test import: - package: github.com/pkg/sftp version: ~1.2.0 - package: golang.org/x/crypto subpackages: - ssh
* 重新更新下載依賴
[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 成功解決
4. 總結
以需求驅動技術，技術本身沒有優略之分，只有業務之分。