Fix error handling context

3 files changed, 65 insertions, 56 deletions

diff --git a/src/main.rs b/src/main.rs
index 26c3794..4dc6e5e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,5 +1,5 @@
-use anyhow::Result;
-use tera::{Context, Tera};
+use anyhow::{Context, Ok, Result};
+use tera::Tera;
 
 use crate::works::Works;
 
@@ -7,19 +7,25 @@ mod works;
 
 fn main() -> Result<()> {
     // new tera instance
-    let tera = Tera::new("templates/**/*.html")?;
+    let tera = Tera::new("templates/**/*.html").context("Failed to create new Tera instance")?;
 
     // render index.html file
-    let context = Context::new();
-    let output = tera.render("index.html", &context)?;
-    std::fs::write("docs/index.html", output)?;
+    let context = tera::Context::new();
+    let output = tera
+        .render("index.html", &context)
+        .context("Failed to render index.html")?;
+    std::fs::write("docs/index.html", output).context("Failed to write index.html")?;
 
     // render stories.html file
     let stories = std::rc::Rc::new(works::stories::Stories::new_from_file(
-        &std::fs::File::open(std::path::PathBuf::from("stories.json"))?,
+        &std::fs::File::open(std::path::PathBuf::from("stories.json"))
+            .context("Failed to open stories.json")?,
     )?);
-    std::rc::Rc::clone(&stories).render_overview_page(&tera, "stories")?;
-    std::rc::Rc::clone(&stories).render_single_pages(&tera, "story")?;
-
-    anyhow::Ok(())
+    std::rc::Rc::clone(&stories)
+        .render_overview_page(&tera, "stories")
+        .context("Failed to render overview page for stories")?;
+    std::rc::Rc::clone(&stories)
+        .render_single_pages(&tera, "story")
+        .context("Failed to render single pages for stories")?;
+    Ok(())
 }
diff --git a/src/works/mod.rs b/src/works/mod.rs
index cb82168..77dd35d 100644
--- a/src/works/mod.rs
+++ b/src/works/mod.rs
@@ -1,4 +1,4 @@
-use anyhow::{Context, Result};
+use anyhow::{Context, Ok, Result};
 use serde::{Deserialize, Serialize};
 
 pub mod stories;
@@ -8,17 +8,17 @@ pub trait Works: for<'a> Deserialize<'a> + Serialize {
     // create works from the corresponding JSON file,
     // e.g. stories from stories.json
     fn new_from_file(file: &std::fs::File) -> Result<Self> {
-        serde_json::from_reader(std::io::BufReader::new(file))
-            // add error context
-            .with_context(|| format!("Failed to create works from {:?}", &file))
+        let file = serde_json::from_reader(std::io::BufReader::new(file))
+            .with_context(|| format!("Failed to create works from {:#?}", &file))?;
+        Ok(file)
     }
 
     // crate tera context from the group of work
     // tera context can be accessed in HTML tera templating
-    fn create_tera_context(&self) -> Result<tera::Context> {
+    fn create_tera_context(&self) -> tera::Context {
         let mut context = tera::Context::new();
         context.insert("works", &self);
-        anyhow::Ok(context).with_context(|| "Failed to create works")
+        context
     }
 
     // render page for every work
@@ -33,17 +33,24 @@ pub trait Works: for<'a> Deserialize<'a> + Serialize {
     ) -> Result<()> {
         std::fs::write(
             format!("docs/{}.html", filename_without_extension).as_str(),
-            tera_instance.render(
-                format!("{}.html", filename_without_extension).as_str(),
-                &self.create_tera_context()?,
-            )?,
+            tera_instance
+                .render(
+                    format!("{}.html", filename_without_extension).as_str(),
+                    &self.create_tera_context(),
+                )
+                .with_context(|| {
+                    format!(
+                        "Failed rendering overview page for {}",
+                        filename_without_extension
+                    )
+                })?,
         )
-        // add error context
         .with_context(|| {
             format!(
-                "Failed to render overview page for {:?}",
+                "Failed to write overview page for {}",
                 filename_without_extension
             )
-        })
+        })?;
+        Ok(())
     }
 }
diff --git a/src/works/stories.rs b/src/works/stories.rs
index 80ab8de..f86d24a 100644
--- a/src/works/stories.rs
+++ b/src/works/stories.rs
@@ -1,6 +1,4 @@
-use std::format;
-
-use anyhow::Context;
+use anyhow::{Result, Ok, Context};
 use chrono::NaiveDate;
 use serde::{Deserialize, Serialize};
 
@@ -29,50 +27,48 @@ impl super::Works for Stories {
         &self,
         tera_instance: &tera::Tera,
         template_name: &str,
-    ) -> anyhow::Result<()> {
+    ) -> Result<()> {
         let mut result = Vec::new();
         for story in self.0.iter() {
-            if story.update_available()? {
+            if story.update_available().with_context(|| format!("Failed to check for update for {}", story.title))? {
                 let mut context = tera::Context::new();
                 context.insert("story", story);
-                context.insert("text", &story.get_text()?);
+                context.insert("text", &story.get_text().with_context(|| format!("Failed to get text from {}", story.title))?);
                 result.push(std::fs::write(
                     story.get_html_path().as_str(),
-                    tera_instance.render(format!("{}.html", template_name).as_str(), &context)?,
+                    tera_instance.render(format!("{}.html", template_name).as_str(), &context).with_context(|| format!("Failed to render single story page for {}", story.title))?,
                 ));
             }
         }
-        anyhow::Ok(()).with_context(|| "Failed to render single story pages")
+        Ok(())
     }
 
     // create stories from stories.json and add last modification date
-    fn new_from_file(file: &std::fs::File) -> anyhow::Result<Self> {
-        let mut stories: Stories = serde_json::from_reader(std::io::BufReader::new(file))?;
+    fn new_from_file(file: &std::fs::File) -> Result<Self> {
+        let mut stories: Stories = serde_json::from_reader(std::io::BufReader::new(file)).with_context(|| format!("Failed to read JSON from {:#?}", file))?;
         for story in stories.0.iter_mut() {
-            story.get_last_modified()?;
-            story.get_pages_num()?;
+            story.get_last_modified().with_context(|| format!("Failed to get last modified date for {}", story.title))?;
+            story.get_pages_num().with_context(|| format!("Failed to get number of pages from {}'s PDF", story.title))?;
         }
-        // add error context
-        anyhow::Ok(stories).with_context(|| format!("Failed to create new story {:?}", file))
+        Ok(stories)
     }
 }
 
 impl Story {
     // check if it's necessary to re-compile the html single page
-    fn update_available(&self) -> anyhow::Result<bool> {
-        anyhow::Ok(
+    fn update_available(&self) -> Result<bool> {
+        Ok(
             // HTML file doesn't exist yet
             !std::path::Path::new(&self.get_html_path()).exists() 
             // pdf document changes
-            || std::fs::metadata(self.get_pdf_path())?.modified()?
-                > std::fs::metadata(self.get_html_path())?.modified()?
+            || std::fs::metadata(self.get_pdf_path()).with_context(|| format!("Failed to get PDF metadata for {}", self.title))?.modified().with_context(|| format!("Failed to get last modified date for {}'s PDF", self.title))?
+                > std::fs::metadata(self.get_html_path()).with_context(|| format!("Failed to get HTML metadata for {}", self.title))?.modified().with_context(|| format!("Failed to get last modified date for {}'s HTML", self.title))?
             // base template changes
-            || std::fs::metadata("templates/base.html")?.modified()?
-                > std::fs::metadata(self.get_html_path())?.modified()?
+            || std::fs::metadata("templates/base.html").context("Failed to get metadata for base HTML template")?.modified().context("Failed to get last modified date for base HTML template")?
+                > std::fs::metadata(self.get_html_path()).with_context(|| format!("Failed to get HTML metadata for {}", self.title))?.modified().with_context(|| format!("Failed to get last modified date for {}'s HTML", self.title))?
             // story template changes
-            ||std::fs::metadata("templates/story.html")?.modified()? > std::fs::metadata(self.get_html_path())?.modified()?, // add error context
+            ||std::fs::metadata("templates/story.html").context("Failed to get metadata for story HTML template")?.modified().context("Failed to get last modified date for story HTML template")? > std::fs::metadata(self.get_html_path()).with_context(|| format!("Failed to get HTML metadata for {}", self.title))?.modified().with_context(|| format!("Failed to get last modified date for {}'s HTML", self.title))?, // add error context
         )
-        .with_context(|| format!("Failed to check for update for {}", self.title))
     }
 
     // use story document name for the single page
@@ -98,31 +94,31 @@ impl Story {
     }
 
     // extract text from pdf document
-    fn get_text(&self) -> anyhow::Result<String> {
-        let text = std::fs::read_to_string(self.get_content_html_path())?;
-        anyhow::Ok(text).with_context(|| format!("Failed to extract text for {}", self.title))
+    fn get_text(&self) -> Result<String> {
+        let text = std::fs::read_to_string(self.get_content_html_path()).with_context(|| format!("Failed to read {}'s content HTML file", self.title))?;
+        Ok(text)
     }
 
     // get date of last modification 
-    fn get_last_modified(&mut self) -> anyhow::Result<chrono::NaiveDate> {
+    fn get_last_modified(&mut self) -> Result<chrono::NaiveDate> {
         use std::os::linux::fs::MetadataExt;
-        let pdf_last_modification = std::fs::metadata(self.get_pdf_path())?.st_mtime();
+        let pdf_last_modification = std::fs::metadata(self.get_pdf_path()).with_context(|| format!("Failed to get {}'s PDF", self.title))?.st_mtime();
         let html_path = std::fs::metadata(self.get_html_path());
-        let html_last_modification = if let Ok(file) = html_path {
+        let html_last_modification = if let core::result::Result::Ok(file) = html_path {
             file.st_mtime()
         } else {
             0
         };
         let date = chrono::NaiveDateTime::from_timestamp(std::cmp::max(pdf_last_modification, html_last_modification), 0).date();
         self.last_update = date;
-        anyhow::Ok(date).with_context(|| format!("Failed to get last modified date for {}", self.title)) 
+        Ok(date)
     }
 
     // get number of pages of pdf file
-    fn get_pages_num(&mut self) -> anyhow::Result<u32> {
-        let file = pdf::file::File::open(self.get_pdf_path())?;
+    fn get_pages_num(&mut self) -> Result<u32> {
+        let file = pdf::file::File::open(self.get_pdf_path()).with_context(|| format!("Failed to get {}'s PDF", self.title))?;
         self.number_of_pages = file.num_pages();
-        anyhow::Ok(file.num_pages()).with_context(|| format!("Failed to number of pages for {}", self.title))
+        Ok(file.num_pages())
     }
 }