DockerExec runs a command in a container, forwards its stdin/stdout/stderr to/from the reader/writers passed as arguments and waits for the command to complete with exit code 0.

DockerImagePull pulls an image from the registry.

ForwardDockerContainerOutput attaches to a docker container and forwards all its output to a writer.

GetEnvDefault returns the value of an environment variable or a default value if the variable is not set.

MustString panics if err != nil and returns s otherwise.

MustT returns a struct with receiver functions that fail the given testing.TB on errors.

PrettySelect performs a query on the given database connection, retrieves the result set, pretty-prints it and returns the result as a string suitable for writing into a log for debugging.

RandomString returns a string of length len consisting of random characters (alphanumeric).

LineWriter implements io.WriteCloser and calls the given callback for every line written to it.

DB is an interface that contains functions provided by *database/sql.DB and *github.com/jmoiron/sqlx.DB required by functions in this package so that in can be used with both.