Module exec 

Exec runtime: render the parsed Exec mini-language into shell text and run it through /bin/sh.

The pipeline AST itself is produced by crate::parse::exec; this module is concerned with turning typed request values into shell-safe words.

Semantics:

• A ValueRef is resolved against an ExecContext (query/path/header/ var maps and a BodyValue).
• A Text token is always emitted as one argv element. Missing interpolations render as the empty string.
• A [..] Group token is used for shell words that contain interpolation. It is emitted only if every interpolation resolves; otherwise the whole group is omitted.
• Request values interpolated into shell text are single-quoted. Literal shell syntax written by the spec author remains literal shell syntax.
• A binary body or binary form field used outside stdin is written to a temp file and the path is interpolated as a quoted shell word.
• Pipeline stages are wired stdin → stdout. A bare Source stage ($ | cmd) feeds a value as stdin to the next command. Multiple statements (multi-line Exec) are joined into a single shell script separated by newlines.

Structs

ExecCompletion

ExecContext

ExecOutput

StreamingExec

A handle to a streaming exec: the receiver yields stdout chunks as they are produced; the join handle resolves with the final exit status (and any\n/// captured stderr) once the process completes.

Enums

BodyValue

FormFieldValue

Functions

build_argv

preview_pipeline

Render a human-readable, non-executing preview of statements against ctx. Used by --dry-run to log the commands that would have run.

run_pipeline

run_pipeline_streaming