From e9ea54bc1b9d52da0a1606227ad8095fe7082998 Mon Sep 17 00:00:00 2001
From: Matti Pastell <matti.pastell@helsinki.fi>
Date: Mon, 4 Mar 2019 11:10:02 +0200
Subject: [PATCH] Allow setting options in document header. Closes #189

---
 doc/src/usage.md | 16 ++++++++++++++++
 src/Weave.jl     | 11 ++++++++++-
 src/config.jl    | 32 ++++++++++++++++++++++++++++++++
 3 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/doc/src/usage.md b/doc/src/usage.md
index 57677ae..f698f4b 100644
--- a/doc/src/usage.md
+++ b/doc/src/usage.md
@@ -120,6 +120,22 @@ added to output e.g. to include a Plots figure in markdown you can use:
 ![A plot](`j plot(1:10)`)
 ```
 
+## Setting document options in header
+
+You can use a YAML header in the beginning of the input document delimited with "---" to set the document title, author and date e.g. and default document options. Each of Weave command line arguments can be set in header using `options` field. Below is an example that sets document `out_path` and `doctype` using the header.
+
+
+```
+---
+title : Weave example
+author : Matti Pastell
+date: 15th December 2016
+options:
+  out_path : reports/example.md
+  doctype :  github
+---
+```
+
 ## Passing arguments to documents
 
 You can pass arguments as dictionary to the weaved document using the `args` argument
diff --git a/src/Weave.jl b/src/Weave.jl
index 7cb4232..e3c8f1c 100644
--- a/src/Weave.jl
+++ b/src/Weave.jl
@@ -98,6 +98,15 @@ function weave(source ; doctype = :auto,
         latex_cmd = "xelatex")
 
     doc = read_doc(source, informat)
+
+    # Read args from document header, overrides command line args
+    if haskey(doc.header, "options")
+        (doctype, informat, out_path, args, mod, fig_path, fig_ext,
+        cache_path, cache, throw_errors, template, highlight_theme, css,
+        pandoc_options, latex_cmd) = parse_header_options(doc)
+    end
+
+
     highlight_theme != nothing && (doc.highlight_theme = highlight_theme)
     #theme != nothing && (doc.theme = theme) #Reserved for themes
     css != nothing && (doc.css = css)
@@ -213,8 +222,8 @@ const postexecute_hooks = Function[]
 push_postexecute_hook(f::Function) = push!(postexecute_hooks, f)
 pop_postexecute_hook(f::Function) = splice!(postexecute_hooks, findfirst(postexecute_hooks, f))
 
-include("config.jl")
 include("chunks.jl")
+include("config.jl")
 include("WeaveMarkdown/markdown.jl")
 include("display_methods.jl")
 include("readers.jl")
diff --git a/src/config.jl b/src/config.jl
index 7182903..96ff77b 100644
--- a/src/config.jl
+++ b/src/config.jl
@@ -85,3 +85,35 @@ function restore_chunk_defaults()
   merge!(rcParams[:chunk_defaults], docParams)
   return nothing
 end
+
+
+getvalue(d::Dict, key , default) = haskey(d, key) ? d[key] : default
+
+"""
+`parse_header_options(doc::WeaveDoc)`
+
+Parse document options from document header
+"""
+function parse_header_options(doc::WeaveDoc)
+    args = getvalue(doc.header, "options", Dict())
+
+    doctype = getvalue(args, "doctype", :auto)
+    informat = getvalue(args, "informat", :auto)
+    out_path = getvalue(args, "out_path", "doc")
+    out_path == ":pwd" && (out_path = :pwd)
+    mod = Symbol(getvalue(args, "mod", :sandbox))
+    fig_path = getvalue(args, "fig_path", "figures")
+    fig_ext = getvalue(args, "fig_ext", nothing)
+    cache_path = getvalue(args, "cache_path", "cache")
+    cache = Symbol(getvalue(args, "cache", :off))
+    throw_errors = getvalue(args, "throw_errors", false)
+    template = getvalue(args, "template", nothing)
+    highlight_theme = getvalue(args, "highlight_theme", nothing)
+    css = getvalue(args, "css", nothing)
+    pandoc_options = getvalue(args, "pandoc_options", String[])
+    latex_cmd = getvalue(args, "latex_cmd", "xelatex")
+
+    return (doctype, informat, out_path, args, mod, fig_path, fig_ext,
+      cache_path, cache, throw_errors, template, highlight_theme, css,
+      pandoc_options, latex_cmd)
+end