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26 lines
960 B
Markdown
26 lines
960 B
Markdown
# Get The Output Of Running A System Program
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Ruby has a [variety of ways](https://stackoverflow.com/a/18623297/535590) to
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execute a system program within a Ruby process. The backticks approach is the
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handy shorthand approach to reach for if you want to capture the output of the
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command.
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For instance, let's say I want to capture the connection string credentials
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output by running a `heroku` command. When the command is wrapped in backticks,
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Ruby will execute it in a subprocess and the output of the command will be the
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return value.
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```ruby
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result = `heroku pg:credentials:url DATABASE_URL --app my-app`
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# extract connection details
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connection_info = result.split("\n")[2].strip
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```
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With the result in hand, I can use Ruby to parse out the details I'm interested
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in.
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Backticks does two other nice things. It allows for string interpolation and it
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puts the process status (e.g. exit code) on
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[`$?`](check-return-status-of-running-a-shell-command.md).
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