git config credential.https://example.com.username myusername git config credential.helper "$helper $options"
Git will sometimes need credentials from the user in order to perform operations; for example, it may need to ask for a username and password in order to access a remote repository over HTTP. This manual describes the mechanisms Git uses to request these credentials, as well as some features to avoid inputting these credentials repeatedly.
Without any credential helpers defined, Git will try the following strategies to ask the user for usernames and passwords:
It can be cumbersome to input the same credentials over and over. Git provides two methods to reduce this annoyance:
The first is simple and appropriate if you do not have secure storage available for a password. It is generally configured by adding this to your config:
[credential "https://example.com"] username = me
Credential helpers, on the other hand, are external programs from which Git can request both usernames and passwords; they typically interface with secure storage provided by the OS or other programs.
To use a helper, you must first select one to use. Git currently includes the following helpers:
You may also have third-party helpers installed; search for credential-* in the output of git help -a, and consult the documentation of individual helpers. Once you have selected a helper, you can tell Git to use it by putting its name into the credential.helper variable.
$ git help -a | grep credential- credential-foo
$ git help credential-foo
$ git config --global credential.helper foo
Git considers each credential to have a context defined by a URL. This context is used to look up context-specific configuration, and is passed to any helpers, which may use it as an index into secure storage.
For instance, imagine we are accessing https://example.com/foo.git. When Git looks into a config file to see if a section matches this context, it will consider the two a match if the context is a more-specific subset of the pattern in the config file. For example, if you have this in your config file:
[credential "https://example.com"] username = foo
then we will match: both protocols are the same, both hosts are the same, and the "pattern" URL does not care about the path component at all. However, this context would not match:
[credential "https://kernel.org"] username = foo
because the hostnames differ. Nor would it match foo.example.com; Git compares hostnames exactly, without considering whether two hosts are part of the same domain. Likewise, a config entry for http://example.com would not match: Git compares the protocols exactly.
Options for a credential context can be configured either in credential.* (which applies to all credentials), or credential.<url>.*, where <url> matches the context as described above.
The following options are available in either location:
If there are multiple instances of the credential.helper configuration variable, each helper will be tried in turn, and may provide a username, password, or nothing. Once Git has acquired both a username and a password, no more helpers will be tried.
If credential.helper is configured to the empty string, this resets the helper list to empty (so you may override a helper set by a lower-priority config file by configuring the empty-string helper, followed by whatever set of helpers you would like).
You can write your own custom helpers to interface with any system in which you keep credentials. See the documentation for Git's m[blue]credentials APIm for details.
Part of the git(1) suite