Download the version you need, untar, and install to your PATH.
$ wget https://github.com/nginx-proxy/docker-gen/releases/download/0.7.6/docker-gen-linux-amd64-0.7.6.tar.gz
$ tar xvzf docker-gen-linux-amd64-0.7.6.tar.gz
$ ./docker-gen
Bundled Container Install
Docker-gen can be bundled inside of a container along-side applications.
nginx-proxy/nginx-proxy trusted build is an example of
running docker-gen within a container along-side nginx.
jwilder/docker-register is an example of running
docker-gen within a container to do service registration with etcd.
Separate Container Install
It can also be run as two separate containers using the nginx-proxy/docker-gen
image, together with virtually any other image.
This is how you could run the official nginx image and
have docker-gen generate a reverse proxy config in the same way that nginx-proxy works. You may want to do
this to prevent having the docker socket bound to a publicly exposed container service.
$ docker-gen
Usage: docker-gen [options] template [dest]
Generate files from docker container meta-data
Options:
-config value
config files with template directives. Config files will be merged if this option is specified multiple times. (default [])
-endpoint string
docker api endpoint (tcp|unix://..). Default unix:///var/run/docker.sock
-interval int
notify command interval (secs)
-keep-blank-lines
keep blank lines in the output file
-notify restart xyz
run command after template is regenerated (e.g restart xyz)
-notify-output
log the output(stdout/stderr) of notify command
-notify-container container-ID
container to send a signal to
-notify-signal signal
signal to send to the -notify-container. -1 to call docker restart. Defaults to 1 aka. HUP.
All available signals available on the [dockerclient](https://github.com/fsouza/go-dockerclient/blob/01804dec8a84d0a77e63611f2b62d33e9bb2b64a/signal.go)
-notify-sighup container-ID
send HUP signal to container. Equivalent to 'docker kill -s HUP container-ID', or `-notify-container container-ID -notify-signal 1`
-only-exposed
only include containers with exposed ports
-only-published
only include containers with published ports (implies -only-exposed)
-include-stopped
include stopped containers
-tlscacert string
path to TLS CA certificate file (default "/Users/jason/.docker/machine/machines/default/ca.pem")
-tlscert string
path to TLS client certificate file (default "/Users/jason/.docker/machine/machines/default/cert.pem")
-tlskey string
path to TLS client key file (default "/Users/jason/.docker/machine/machines/default/key.pem")
-tlsverify
verify docker daemon's TLS certicate (default true)
-version
show version
-watch
watch for container changes
-wait
minimum (and/or maximum) duration to wait after each container change before triggering
Arguments:
template - path to a template to generate
dest - path to write the template. If not specfied, STDOUT is used
Environment Variables:
DOCKER_HOST - default value for -endpoint
DOCKER_CERT_PATH - directory path containing key.pem, cert.pm and ca.pem
DOCKER_TLS_VERIFY - enable client TLS verification]
If no <dest> file is specified, the output is sent to stdout. Mainly useful for debugging.
Configuration file
Using the -config flag from above you can tell docker-gen to use the specified config file instead of command-line options. Multiple templates can be defined and they will be executed in the order that they appear in the config file.
An example configuration file, docker-gen.cfg can be found in the examples folder.
Configuration File Syntax
[[config]]
Starts a configuration section
dest = "path/to/a/file"
path to write the template. If not specfied, STDOUT is used
notifycmd = "/etc/init.d/foo reload"
run command after template is regenerated (e.g restart xyz)
onlyexposed = true
only include containers with exposed ports
template = "/path/to/a/template/file.tmpl"
path to a template to generate
watch = true
watch for container changes
wait = "500ms:2s"
debounce changes with a min:max duration. Only applicable if watch = true
[config.NotifyContainers]
Starts a notify container section
containername = 1
container name followed by the signal to send
container_id = 1
or the container id can be used followed by the signal to send
Putting it all together here is an example configuration file.
[[config]]
template = "/etc/nginx/nginx.conf.tmpl"
dest = "/etc/nginx/sites-available/default"
onlyexposed = true
notifycmd = "/etc/init.d/nginx reload"
[[config]]
template = "/etc/logrotate.conf.tmpl"
dest = "/etc/logrotate.d/docker"
watch = true
[[config]]
template = "/etc/docker-gen/templates/nginx.tmpl"
dest = "/etc/nginx/conf.d/default.conf"
watch = true
wait = "500ms:2s"
[config.NotifyContainers]
nginx = 1 # 1 is a signal number to be sent; here SIGHUP
e75a60548dc9 = 1 # a key can be either container name (nginx) or ID
===
Templating
The templates used by docker-gen are written using the Go text/template language. In addition to the built-in functions supplied by Go, docker-gen uses sprig and some additional functions to make it simpler (or possible) to generate your desired output.
Emit Structure
Within the templates, the object emitted by docker-gen will be a structure consisting of following Go structs:
typeRuntimeContainerstruct {
IDstringAddresses []AddressNetworks []NetworkGatewaystringNamestringHostnamestringImageDockerImageEnvmap[string]stringVolumesmap[string]VolumeNodeSwarmNodeLabelsmap[string]stringIPstringIP6LinkLocalstringIP6GlobalstringMounts []MountStateState
}
typeAddressstruct {
IPstringIP6LinkLocalstringIP6GlobalstringPortstringHostPortstringProtostringHostIPstring
}
typeNetworkstruct {
IPstringNamestringGatewaystringEndpointIDstringIPv6GatewaystringGlobalIPv6AddressstringMacAddressstringGlobalIPv6PrefixLenintIPPrefixLenint
}
typeDockerImagestruct {
RegistrystringRepositorystringTagstring
}
typeMountstruct {
NamestringSourcestringDestinationstringDriverstringModestringRWbool
}
typeVolumestruct {
PathstringHostPathstringReadWritebool
}
typeSwarmNodestruct {
IDstringNamestringAddressAddress
}
typeStatestruct {
Runningbool
}
// Accessible from the root in templates as .DockertypeDockerstruct {
NamestringNumContainersintNumImagesintVersionstringApiVersionstringGoVersionstringOperatingSystemstringArchitecturestringCurrentContainerIDstring
}
// Host environment variables accessible from root in templates as .Env
For example, this is a JSON version of an emitted RuntimeContainer struct:
Functions from Sprig v3, except for those that have the same name as one of the following functions.
closest $array $value: Returns the longest matching substring in $array that matches $value
coalesce ...: Returns the first non-nil argument.
contains $map $key: Returns true if $map contains $key. Takes maps from string to any type.
dir $path: Returns an array of filenames in the specified $path.
exists $path: Returns true if $path refers to an existing file or directory. Takes a string.
groupBy $containers $fieldPath: Groups an array of RuntimeContainer instances based on the values of a field path expression $fieldPath. A field path expression is a dot-delimited list of map keys or struct member names specifying the path from container to a nested value, which must be a string. Returns a map from the value of the field path expression to an array of containers having that value. Containers that do not have a value for the field path in question are omitted.
groupByKeys $containers $fieldPath: Returns the same as groupBy but only returns the keys of the map.
groupByMulti $containers $fieldPath $sep: Like groupBy, but the string value specified by $fieldPath is first split by $sep into a list of strings. A container whose $fieldPath value contains a list of strings will show up in the map output under each of those strings.
groupByLabel $containers $label: Returns the same as groupBy but grouping by the given label's value.
intersect $slice1 $slice2: Returns the strings that exist in both string slices.
json $value: Returns the JSON representation of $value as a string.
keys $map: Returns the keys from $map. If $map is nil, a nil is returned. If $map is not a map, an error will be thrown.
parseBool $string: parseBool returns the boolean value represented by the string. It accepts 1, t, T, TRUE, true, True, 0, f, F, FALSE, false, False. Any other value returns an error. Alias for strconv.ParseBool
replace $string $old $new $count: Replaces up to $count occurences of $old with $new in $string. Alias for strings.Replace
sha1 $string: Returns the hexadecimal representation of the SHA1 hash of $string.
split $string $sep: Splits $string into a slice of substrings delimited by $sep. Alias for strings.Split
splitN $string $sep $count: Splits $string into a slice of substrings delimited by $sep, with number of substrings returned determined by $count. Alias for strings.SplitN
*sortStringsAsc $strings: Returns a slice of strings $strings sorted in ascending order.
*sortStringsDesc $strings: Returns a slice of strings $strings sorted in descending (reverse) order.
*sortObjectsByKeysAsc $objects $fieldPath: Returns the array $objects, sorted in ascending order based on the values of a field path expression $fieldPath.
*sortObjectsByKeysDesc $objects $fieldPath: Returns the array $objects, sorted in descending (reverse) order based on the values of a field path expression $fieldPath.
trimPrefix $prefix $string: If $prefix is a prefix of $string, return $string with $prefix trimmed from the beginning. Otherwise, return $string unchanged.
trimSuffix $suffix $string: If $suffix is a suffix of $string, return $string with $suffix trimmed from the end. Otherwise, return $string unchanged.
toLower $string: Replace capital letters in $string to lowercase.
toUpper $string: Replace lowercase letters in $string to uppercase.
when $condition $trueValue $falseValue: Returns the $trueValue when the $condition is true and the $falseValue otherwise
where $items $fieldPath $value: Filters an array or slice based on the values of a field path expression $fieldPath. A field path expression is a dot-delimited list of map keys or struct member names specifying the path from container to a nested value. Returns an array of items having that value.
whereNot $items $fieldPath $value: Filters an array or slice based on the values of a field path expression $fieldPath. A field path expression is a dot-delimited list of map keys or struct member names specifying the path from container to a nested value. Returns an array of items not having that value.
whereExist $items $fieldPath: Like where, but returns only items where $fieldPath exists (is not nil).
whereNotExist $items $fieldPath: Like where, but returns only items where $fieldPath does not exist (is nil).
whereAny $items $fieldPath $sep $values: Like where, but the string value specified by $fieldPath is first split by $sep into a list of strings. The comparison value is a string slice with possible matches. Returns items which OR intersect these values.
whereAll $items $fieldPath $sep $values: Like whereAny, except all $values must exist in the $fieldPath.
whereLabelExists $containers $label: Filters a slice of containers based on the existence of the label $label.
whereLabelDoesNotExist $containers $label: Filters a slice of containers based on the non-existence of the label $label.
whereLabelValueMatches $containers $label $pattern: Filters a slice of containers based on the existence of the label $label with values matching the regular expression $pattern.
This template is an example of generating a script that is then executed. This template generates
a python script that is then executed which register containers in Etcd using its HTTP API.
请发表评论