Performing basic builds | Builds | OpenShift Container Platform 4.5

Starting a build
Canceling a build
Deleting a BuildConfig
Viewing build details
Accessing build logs

The following sections provide instructions for basic build operations including starting and canceling builds, deleting BuildConfigs, viewing build details, and accessing build logs.

Starting a build

You can manually start a new build from an existing build configuration in your current project.

Procedure

To manually start a build, enter the following command:

$ oc start-build <buildconfig_name>

Re-running a build

You can manually re-run a build using the --from-build flag.

Procedure

To manually re-run a build, enter the following command:
```
$ oc start-build --from-build=<build_name>
```

Streaming build logs

You can specify the --follow flag to stream the build’s logs in stdout.

Procedure

To manually stream a build’s logs in stdout, enter the following command:
```
$ oc start-build <buildconfig_name> --follow
```

Setting environment variables when starting a build

You can specify the --env flag to set any desired environment variable for the build.

Procedure

To specify a desired environment variable, enter the following command:
```
$ oc start-build <buildconfig_name> --env=<key>=<value>
```

Starting a build with source

Rather than relying on a Git source pull or a Dockerfile for a build, you can also start a build by directly pushing your source, which could be the contents of a Git or SVN working directory, a set of pre-built binary artifacts you want to deploy, or a single file. This can be done by specifying one of the following options for the start-build command:

Option Description

Option	Description
`--from-dir=<directory>`	Specifies a directory that will be archived and used as a binary input for the build.
`--from-file=<file>`	Specifies a single file that will be the only file in the build source. The file is placed in the root of an empty directory with the same file name as the original file provided.
`--from-repo=<local_source_repo>`	Specifies a path to a local repository to use as the binary input for a build. Add the `--commit` option to control which branch, tag, or commit is used for the build.

--from-dir=<directory>

Specifies a directory that will be archived and used as a binary input for the build.

--from-file=<file>

Specifies a single file that will be the only file in the build source. The file is placed in the root of an empty directory with the same file name as the original file provided.

--from-repo=<local_source_repo>

Specifies a path to a local repository to use as the binary input for a build. Add the --commit option to control which branch, tag, or commit is used for the build.

When passing any of these options directly to the build, the contents are streamed to the build and override the current build source settings.

Builds triggered from binary input will not preserve the source on the server, so rebuilds triggered by base image changes will use the source specified in the build configuration.

Procedure

Start a build from a source using the following command to send the contents of a local Git repository as an archive from the tag v2:
```
$ oc start-build hello-world --from-repo=../hello-world --commit=v2
```

Canceling a build

You can cancel a build using the web console, or with the following CLI command.

Procedure

To manually cancel a build, enter the following command:
```
$ oc cancel-build <build_name>
```

Canceling multiple builds

You can cancel multiple builds with the following CLI command.

Procedure

To manually cancel multiple builds, enter the following command:
```
$ oc cancel-build <build1_name> <build2_name> <build3_name>
```

Canceling all builds

You can cancel all builds from the build configuration with the following CLI command.

Procedure

To cancel all builds, enter the following command:
```
$ oc cancel-build bc/<buildconfig_name>
```

Canceling all builds in a given state

You can cancel all builds in a given state, such as new or pending, while ignoring the builds in other states.

Procedure

To cancel all in a given state, enter the following command:
```
$ oc cancel-build bc/<buildconfig_name>
```

Deleting a BuildConfig

You can delete a BuildConfig using the following command.

Procedure

To delete a BuildConfig, enter the following command:
```
$ oc delete bc <BuildConfigName>
```
This also deletes all builds that were instantiated from this BuildConfig.
To delete a BuildConfig and keep the builds instatiated from the BuildConfig, specify the --cascade=false flag when you enter the following command:
```
$ oc delete --cascade=false bc <BuildConfigName>
```

Viewing build details

You can view build details with the web console or by using the oc describe CLI command.

This displays information including:

The build source.
The build strategy.
The output destination.
Digest of the image in the destination registry.
How the build was created.

If the build uses the Docker or Source strategy, the oc describe output also includes information about the source revision used for the build, including the commit ID, author, committer, and message.

Procedure

To view build details, enter the following command:
```
$ oc describe build <build_name>
```

Accessing build logs

You can access build logs using the web console or the CLI.

Procedure

To stream the logs using the build directly, enter the following command:
```
$ oc describe build <build_name>
```

Accessing BuildConfig logs

You can access BuildConfig logs using the web console or the CLI.

Procedure

To stream the logs of the latest build for a BuildConfig, enter the following command:
```
$ oc logs -f bc/<buildconfig_name>
```

Accessing BuildConfig logs for a given version build

You can access logs for a given version build for a BuildConfig using the web console or the CLI.

Procedure

To stream the logs for a given version build for a BuildConfig, enter the following command:
```
$ oc logs --version=<number> bc/<buildconfig_name>
```

Enabling log verbosity

You can enable a more verbose output by passing the BUILD_LOGLEVEL environment variable as part of the sourceStrategy or dockerStrategy in a BuildConfig.

An administrator can set the default build verbosity for the entire OpenShift Container Platform instance by configuring env/BUILD_LOGLEVEL. This default can be overridden by specifying BUILD_LOGLEVEL in a given BuildConfig. You can specify a higher priority override on the command line for non-binary builds by passing --build-loglevel to oc start-build.

Available log levels for source builds are as follows:

Level 0	Produces output from containers running the `assemble` script and all encountered errors. This is the default.
Level 1	Produces basic information about the executed process.
Level 2	Produces very detailed information about the executed process.
Level 3	Produces very detailed information about the executed process, and a listing of the archive contents.
Level 4	Currently produces the same information as level 3.
Level 5	Produces everything mentioned on previous levels and additionally provides docker push messages.

Procedure

To enable more verbose output, pass the BUILD_LOGLEVEL environment variable as part of the sourceStrategy or dockerStrategy in a BuildConfig:
```
sourceStrategy:
...
  env:
    - name: "BUILD_LOGLEVEL"
      value: "2" (1)
```
1 Adjust this value to the desired log level.