From 489fe5339ef3e93c1f19401fc7d2f4d9a367dbd4 Mon Sep 17 00:00:00 2001
From: Stefan Bringuier <stefanbringuier@gmail.com>
Date: Fri, 7 Apr 2023 11:37:07 -0700
Subject: [PATCH 1/5] Fallback support for failed metadata retrieval (Fixes
 #13).

---
 src/doi.jl | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/src/doi.jl b/src/doi.jl
index 4f167f6..4e99dc5 100644
--- a/src/doi.jl
+++ b/src/doi.jl
@@ -59,13 +59,26 @@ function Base.show(io::IO, ::MIME"text/html", dois::Array{T} where {T<:AbstractD
     print(io, "</ol>")
 end
 
+"""
+    meta-data structure from API: https://w3id.org/oc/meta/api/v1/metadata/
+""" function metadata_template(doi::String)
+    fields = (:publisher, :pub_date, :page, :venue, :issue, :editor, :author, :id, :volume, :title, :type)
+    r1 = Dict(f=>"\u0000" for f in fields)
+    r1[:id] = doi
+    return r1
+end
+
 @memoize function fetch_metadata(doi::AbstractDOI)
     fetch_metadata(doi.doi)
 end
 @memoize function fetch_metadata(doi)
     r = HTTP.get("https://w3id.org/oc/meta/api/v1/metadata/doi:$(doi)")
     rj = JSON3.read(r.body)
-    return rj[1]
+    if isempty(rj)
+        return metadata_template(doi)
+    else
+        return rj[1]
+    end
 end
 fetch_citation_count(doi::AbstractDOI) = fetch_citation_count(doi.doi)
 @memoize function fetch_citation_count(doi)
@@ -130,5 +143,5 @@ function strip(s)
     return replace(s, r" \[(.*?)\]" => "")
 end
 function year(s)
-    return parse(Int, first(s, 4))
+    return !isempty(s) ? parse(Int, first(s, 4)) : "\u0000"
 end

From eda6487f9c805907bd274f0b612ed6c4311e72f5 Mon Sep 17 00:00:00 2001
From: Stefan Bringuier <stefanbringuier@gmail.com>
Date: Sun, 9 Apr 2023 00:22:11 -0700
Subject: [PATCH 2/5] Add null case and change return value.

---
 src/doi.jl | 14 ++++++++------
 1 file changed, 8 insertions(+), 6 deletions(-)

diff --git a/src/doi.jl b/src/doi.jl
index 4e99dc5..e92097b 100644
--- a/src/doi.jl
+++ b/src/doi.jl
@@ -61,11 +61,12 @@ end
 
 """
     meta-data structure from API: https://w3id.org/oc/meta/api/v1/metadata/
-""" function metadata_template(doi::String)
+"""
+function metadata_template(doi::String)
     fields = (:publisher, :pub_date, :page, :venue, :issue, :editor, :author, :id, :volume, :title, :type)
-    r1 = Dict(f=>"\u0000" for f in fields)
-    r1[:id] = doi
-    return r1
+    rj = Dict(f => "\u0000" for f in fields)
+    rj[:id] = doi
+    return rj
 end
 
 @memoize function fetch_metadata(doi::AbstractDOI)
@@ -119,7 +120,7 @@ end
 function emph_author(doi::EmDOI)
     emph_author(strip(doi.author), doi.highlight)
 end
-function emph_author(authors, author = "", em = "b")
+function emph_author(authors, author="", em="b")
     orcid = r", \d{4}-\d{4}-\d{4}-\d{4}"
     authors = replace(authors, orcid => "")
     if length(author) > 2
@@ -142,6 +143,7 @@ end
 function strip(s)
     return replace(s, r" \[(.*?)\]" => "")
 end
+
 function year(s)
-    return !isempty(s) ? parse(Int, first(s, 4)) : "\u0000"
+    return !isempty(s) && s != "\0" ? parse(Int, first(s, 4)) : nothing
 end

From c9d7d9c4c0aebc6790283160479afcb502d33620 Mon Sep 17 00:00:00 2001
From: Stefan Bringuier <stefanbringuier@gmail.com>
Date: Sun, 9 Apr 2023 00:24:49 -0700
Subject: [PATCH 3/5] Fix nothing return value on year.

---
 src/doi.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/doi.jl b/src/doi.jl
index e92097b..1c85afa 100644
--- a/src/doi.jl
+++ b/src/doi.jl
@@ -145,5 +145,5 @@ function strip(s)
 end
 
 function year(s)
-    return !isempty(s) && s != "\0" ? parse(Int, first(s, 4)) : nothing
+    return !isempty(s) && s != "\0" ? parse(Int, first(s, 4)) : s
 end

From 533fa1ebf653fe36de66d66cb6750e1d1de8246f Mon Sep 17 00:00:00 2001
From: Stefan Bringuier <stefanbringuier@gmail.com>
Date: Fri, 9 Jun 2023 08:31:38 -0700
Subject: [PATCH 4/5] Return empty string.

---
 src/doi.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/doi.jl b/src/doi.jl
index 1c85afa..0a3ebfe 100644
--- a/src/doi.jl
+++ b/src/doi.jl
@@ -145,5 +145,5 @@ function strip(s)
 end
 
 function year(s)
-    return !isempty(s) && s != "\0" ? parse(Int, first(s, 4)) : s
+    return !isempty(s) && s != "" ? parse(Int, first(s, 4)) : s
 end

From d1ea57e15ee6666f69336e48cafe10ad65b05b43 Mon Sep 17 00:00:00 2001
From: hellemo <hellemo@gmail.com>
Date: Sun, 1 Oct 2023 11:33:31 +0200
Subject: [PATCH 5/5] use empty string

---
 src/doi.jl | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/doi.jl b/src/doi.jl
index 0a3ebfe..7fbc6a2 100644
--- a/src/doi.jl
+++ b/src/doi.jl
@@ -64,7 +64,7 @@ end
 """
 function metadata_template(doi::String)
     fields = (:publisher, :pub_date, :page, :venue, :issue, :editor, :author, :id, :volume, :title, :type)
-    rj = Dict(f => "\u0000" for f in fields)
+    rj = Dict(f => "" for f in fields)
     rj[:id] = doi
     return rj
 end